Self-Harm and Suicidality Experiences of Autistic and Non-Autistic Adults in Midlife and Older Age

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Stewart This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6511234/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 25 Nov, 2025 Read the published version in Molecular Autism → Version 1 posted 10 You are reading this latest preprint version Abstract Background Suicide has been reported as a leading cause of premature death in autistic populations. Additionally, risk of suicidality is often found to increase with age in the general population. Despite this, suicidality has seldom been explored in autistic populations in midlife and older age. This study investigates the self-reported prevalence of self-harm and suicidality in autistic people in midlife and older age compared to an age- and gender-matched non-autistic comparison group. Methods In total, 388 participants (autistic n = 222, 44% men) aged 40–93 years (mean = 60.9 years) from the AgeWellAutism study completed questionnaires related to experiences of suicidal ideation, self-harming thoughts, deliberate self-harm, and suicidal self-harm. Group, gender and age differences were examined chi-square and linear regression analyses. Results The autistic group reported significantly higher rates of suicidal ideation, self-harming thoughts, deliberate self-harm, and suicidal self-harm than the non-autistic comparison group. When considering gender differences in the autistic group (but not the non-autistic group due to limited sample size), autistic women reported significantly higher rates of suicidal ideation and suicidal self-harm compared to autistic men; no other gender differences were found. When considering age differences, autistic people in old age were more likely to have had thoughts of self-harm, to have deliberately self-harmed, and to have experienced suicidal self-harm than autistic people in midlife. Limitations: The AgeWellAutism study is a cross-sectional convenience sample that relies on self-report. Survivor bias may also influence findings, as the study design would exclude those who have died by suicide, potentially leading to an underestimation of suicidality. Conclusions Autistic adults may be particularly susceptible to experiences of self-harm and suicidality in midlife and older age, particularly autistic women. Additionally, autistic people in old age were also more likely to experience suicidality (including recent experiences) than autistic people in midlife. These findings highlight the urgent need for targeted suicide prevention strategies and mental health interventions for autistic adults in midlife and older age, particularly autistic women and older people. Autism Self-Harm Suicidality Midlife Older age INTRODUCTION Suicidality – an umbrella term for suicidal ideation, thoughts of harm, deliberate harm, suicide plans, harming with the intention of suicide, and death by suicide – is a global public health concern, with suicide accounting for 11.4 deaths per 100,000 people in the UK (1). While women are more often found to self-harm, death by suicide occurs more commonly among men than women at a ratio of 3.5 to 1, with men often using more lethal methods of suicide (2). While death by suicide has been recorded at all ages, high incidence rates of suicide in the UK are often found in midlife (age 40–64 years), which then peak in older age (64 years and older) (1). Many factors have been attributed to this spike in later life, such as age-related change to health and cognition, and social factors (3). Despite this peak in incidence of suicidality in midlife and older age, few studies have explored whether populations known to be at high risk of suicide, for example autistic people, have increased rates of suicidality in this later age-range. Autism is a lifelong neurodevelopmental condition affecting approximately 1% of the global population (4). Characterised by differences in social communication and rigid-repetitive behaviours and interests, autism plays a significant role in shaping individuals' experiences throughout their lives (5–6). Autistic adults often experience poorer physical and mental health, lower education rates, lower employment rates, higher rates of traumatic events, more sleep disturbances, and lower overall quality of life (7–14). These negative outcomes may be relevant to the high rates of suicidality compared to non-autistic people (15). Multiple studies, including those using extensive population registers (from countries such as Australia, Korea, France, Sweden, Taiwan and the UK) and genetically informed designs (e.g., UKBioBank), have consistently shown that autistic people are at a heightened risk for suicidal ideation (15–17), non-suicidal self-harm (17–20), suicidal self-harm (17, 21–23), and death by suicide (22, 24–26). Estimates pooled from 36 primary studies involving over 46,000 autistic people (age means = 10 to 42 years) suggest that approximately 34% of autistic people have experienced suicidal ideation, 22% have considered plans for suicide, and 24% have harmed themselves with the intention of suicide (15). Suicide has also been found to be a leading cause of premature death in autistic people (ranked third in a Swedish population-based study, accounting for 12% of deaths in a sample of autistic decedents; 24), with autistic people being up to nine times more likely to die by suicide compared to the general population (27). Additionally, unlike in the general population, death by suicide is found to be higher in autistic women than autistic men, highlighting an important consideration for how suicidality is identified and risk assessed autistic populations (26). When considering suicidality in autistic populations in midlife and older age, information is sparse. Despite population estimates suggesting that there are upwards of 250,000 autistic people in the UK over the age of 50 (28), research on middle-aged and older autistic adults accounts for only 0.4% of indexed autism research since 1980 (29–30). To the authors’ knowledge, only one study to date has specifically explored suicidality in midlife and older age in relation to autism. Stewart et al. ( 2023 ; 31), utilising a dimensional trait-based approach to account for high rates of underdiagnosis in midlife and older populations (28), showed that adults with high autistic traits (n = 276, aged 50–81, 31% men) self-reported significantly higher rates of suicidal ideation (72.7% vs. 29.3%), deliberate self-harm (19.9% vs. 4.7%) and suicidal self-harm (12.7% vs. 2.5%) when compared to age and gender-matched low autistic trait individuals (n = 10,495); these higher rates represented a five-to-six-fold increase in the likelihood of suicidality for the high autistic trait participants. Importantly, this pattern remained when accounting for symptoms of depression. When considering possible reasons why middle-aged and older autistic people may have high rates of suicidality, delayed diagnosis and lack of support may play a key role (32–33). Additionally, middle-aged and older autistic people often experience high rates of social isolation and low social support (34–35). These issues fit with the proposed ‘Interpersonal Theory of Suicide’ (36), which offers a valuable framework for understanding why autistic individuals may face heightened suicide risks, emphasising factors like perceived burdensomeness and thwarted belongingness. Despite growing research on autism and suicidality, there remains a significant gap in our understanding of how these issues manifest and change throughout the lifespan, especially in mid-to-late adulthood. This study seeks to replicate and extend the findings of Stewart et al.’s ( 2023 ; 31) trait-based study in a similarly aged sample of autistic adults who have a diagnosis of autism or who self-identify as autistic. We hypothesise that a similar pattern of results will be found in our diagnosed/self-identified autistic sample, namely that: 1) middle-aged and older autistic adults will self-report higher rates of suicidal ideation, self-harming thoughts, deliberate self-harm, and suicidal self-harm than age-and-sex matched non-autistic adults; 2) autistic women will report higher rates of suicidality than autistic men; 3) autistic adults aged 65+ (i.e., older adults) will report more experiences of suicidality than autistic adults aged 40–64 years (i.e., middle-aged adults). METHODS Study Design This study uses cross-sectional data from the first wave of the ‘AgeWellAutism’ study, conducted in Spring 2019. The AgeWellAutism study is an online survey investigating ageing on the autism spectrum (outlined in Stewart et al., (2024; 35)). In brief, the content of the AgeWellAutism study was steered by 12 middle-aged and older autistic adults prior to launch, with recruitment being conducted through social media platforms (i.e., Twitter, Reddit, Facebook), participant databases managed by the author and Autistica's Research Network, and adverts in community centres and older adult residential communities. An incentive of entry into a raffle for a £20 Amazon UK gift voucher was offered. Inclusion criteria were being 40 years of age or above, having access to an internet-enable device, and being able to read and type in English. The study had no specific exclusion criteria. Full ethical approval was granted by the PNM Research Ethics Subcommittee at King's College London (HR-18/19–10941). Participants In total, 502 completed surveys were recorded, with 70 responses being removed due to suspected spam (i.e., very short completion times and/or irregular answers to open-text boxes). For the current study, a further 40 responses were excluded as these individuals opted to skip the self-harm and suicidality questions. An additional four non-binary/trans/agender participants were also omitted due to the small sample size. This resulted in a final sample of 388 participants aged 40-93 years. Participants who disclosed that they either had an autism diagnosis (n=211) or self-identified as autistic (n=11) formed an autistic group (n=222); both subgroups had comparable autistic trait scores ( t (1,223)=1.63, p =.104). The autistic group were asked when they received their autism diagnosis/ began to identify as autistic; responses ranged from as recently as the year of survey completion to 43 years ago (mean years since diagnosis=9.4 years), with nine (4.1%) diagnosed in childhood (i.e., prior to 18 years of age). The remaining participants formed the non-autistic group (n=166). The autistic and non-autistic groups were matched on age (autistic mean age=60.9 years; non-autistic mean age=60.6 years) and gender ratio (autistic group men=44.1%; non-autistic group men=50.6%). Both groups were comparable in education level and in country of residence, with around 98% living in the UK. However, the autistic sample self-reported lower employment rates and a higher likelihood of living with non-marital family members. No data on socio-economic status and race/ethnicity was collected. See Table 1 for demographic characteristics of the autistic and non-autistic groups. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - TABLE 1 (DEMOGRAPHICS) ABOUT HERE - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Materials Demographic Characteristics – Participants provided detailed self-reported demographic information, including age, gender, highest educational attainment, employment status, who they live with, and country of residence. Autism Diagnoses/Self-identification and Autistic Traits - Participants were asked whether they had an autism diagnosis or if they self-identified as autistic. If yes, they were then asked how many years had passed since their diagnosis or they began to self-identify. Additionally, the Ritvo Autism and Asperger Diagnostic Scale (RAADS-14; 37) was used to descriptively explore autistic trait endorsement in each group, to ensure the diagnosed and self-identified autistic participants could be combined into one group. The RAADS-14 is a 14-item questionnaire that explores autistic traits related to mentalising difficulties, sensory reactivity, and social anxiety. Scores range from 0-42, with a score ≥14 having a sensitivity of 97% and specificity of 46%-64% for identifying autism. The RAADS-14 has demonstrated satisfactory psychometric properties (38). In the current study, the RAADS-14 showed very good internal consistency in the autistic group (Cronbach’s a= .887), and good consistency in the non-autistic group (Cronbach’s a= .744). Self-Harm and Suicidality – Experiences of suicidality were measured using the 8-item self-report UK BioBank Self-Harm and Suicidality Questionnaire (31). These questions were presented on an opt-in basis, with the option to skip questions at any point during the block. Suicidal ideation was assessed by asking participants if they: 1) had felt that life was not worth living. For thoughts of harm, participants were asked whether they: 2) had contemplated harming themselves, and whether they: 3) had contemplated harming themselves in the last 12 months. For deliberate harm, frequency of harm, and types of harm, participants were asked: 4) if they had ever deliberately harmed themselves, whether they meant to end their life or not; 5) how many times they had deliberately harmed themselves; 6) if they had deliberately harmed themselves within the last 12 months; and 7) the types of harming behaviours used. For suicidal harm, participants were asked if they: 8) had deliberately taken an overdose or harmed themselves with the intention to end their life. For the complete list of questions and scoring matrix see supplementary materials. The UK BioBank Self-Harm and Suicidality questionnaire has been used in samples previously, including in older adults with high autistic traits (31). In the current study, the scale has very good internal consistency in the autistic (Cronbach’s a =.807) and non-autistic (Cronbach’s a =.849) groups. Depression – Symptoms of depression were measured using the Patient Health Questionnaire (PHQ-8; 39). The PHQ-8 is an eight-item questionnaire with a 4-point scale which asks the participant to report whether they have been bothered by a range of problems over the past two weeks such as anhedonia, low mood, sleep problems, fatigue, poor appetite or weight change, concentration difficulty, and psychomotor disturbance. The PHQ-8 omits the suicidal ideation question included in the nine-item version of the measure (PHQ-9). Using the conventional cut-off score of ≥10, the PHQ-9 has a sensitivity of 88% and a specificity of 88% for major depressive disorder. The PHQ-9 has been validated for use in autistic adults (40). Data Analysis The current study using the AgeWellAutism dataset (specifically hypotheses 1 and 2) was pre-registered prior to analyses being conducted (https://osf.io/qv23s). Hypothesis 3 (i.e., age-differences) was added as a post-hoc analysis and not included in the original pre-registration. All statistical analyses were performed using SPSS (v29.0.2.0; IBM Corp., 2023). Demographic variables and autism-related information was analysed with t-tests (continuous variables) and chi-squared tests (χ²; categorical variables). To address hypothesis 1, χ² analyses were conducted to investigate group differences (autistic vs. non-autistic) in rates of self-harm and suicidality experiences. A series of linear regressions (with suicidality items as outcomes, and autism group and depression scores as predictors) were conducted to examine whether any observed group differences in suicidality were solely a function of worse depression symptomology. To address hypothesis 2, additional layered χ² analyses were performed to examine differences in self-harm and suicidality scores by gender (men vs. women) and group (autistic vs. non-autistic). Adjusted residual values were checked for detecting significant differences in ratings or proportions. To address hypothesis 3, χ² analyses were conducted to investigate age group differences (middle-aged (40-64 years) vs. older age (65+ years)) in rates of self-harm and suicidality experiences in the autistic group; these analyses were not conducted in the non-autistic group due to small group sizes. Multiple comparisons were accounted for by using the False Discovery Rate method (FDR; 41), using an initial alpha level of .050. The FDR procedure was applied to all p-values, and adjusted alpha values were assigned based on the rank of the p -values; final FDR adjusted critical value being .044. RESULTS Group Differences in Self-Harm and Suicidality Suicidal Ideation The autistic group self-reported significantly higher rates and higher frequencies of suicidal ideation compared to the non-autistic group (χ2=129.84, p <.001). In total, 73.0% of the autistic group had experienced suicidal ideation (13.2% once, 59.8% more than once) in comparison to 25.9% of the non-autistic group (21.7% once, 4.2% more than once). The autistic group were almost eight times more likely than non-autistic group to have experienced suicidal ideation at least once. The pattern of results remained when accounting for the influence of current depression symptoms (R 2 =.346, F=105.54, p <.001; depression b =.25, autism group b =.41) . See Table 2. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - TABLE 2 (RATES) ABOUT HERE - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Self-Harming Thoughts The autistic group self-reported significantly higher rates and higher frequencies of self-harming thoughts compared to the non-autistic group (χ 2 =85.67, p <.001). In total, 66.5% of the autistic group (13.3% once, 53.2% more than once) had experienced these thoughts, in comparison to 25.3% of the non-autistic group (16.3% once, 9.0% more than once). The autistic group were nearly six times more likely than the non-autistic group to have experienced self-harming thoughts at least once. The pattern of results remained when accounting for the influence of current depression symptoms (R 2 =.277, F=75.14, p <.001; depression b =.31, autism group b =.28) . See Table 2. Additionally, the autistic group self-reported significantly higher rates of self-harming thoughts within the last 12 months compared to the non-autistic group (χ 2 =69.48, p <.001). In total, 43.6% of the autistic group had contemplated self-harm recently, compared to 5.4% of the non-autistic group. The autistic group were thirteen times more likely than the non-autistic group to have experienced self-harming thoughts in the last year. The pattern of results remained when accounting for the influence of current depression symptoms (R 2 =.265, F=70.68, p <.001; depression b =.37, autism group b =.20) . Deliberate Self-Harm The autistic group self-reported significantly higher rates of deliberate self-harm compared to the non-autistic group (χ 2 =69.29, p <.001). In total, 55.0% of the autistic group had deliberately self-harmed, compared to 13.3% of the non-autistic group. The autistic group were nearly eight times more likely than the non-autistic comparison group to have deliberately self-harmed at least once. Among those who had deliberately self-harmed, the autistic group reported significantly higher frequencies of self-harm incidents than the non-autistic group (χ 2 =22.62, p <.001). Of those who had deliberately self-harmed, 85.1% of the autistic group had two or more incidents of harm compared to 45.8% of the non-autistic group. The patterns of results remained when accounting for the influence of current depression symptoms (R 2 =.279, F=76.09, p <.001; depression b =.37, autism group b =.21) . See Table 2. Additionally, the autistic group self-reported significantly higher rates of deliberate self-harm within the last 12 months compared to the non-autistic group (χ 2 =16.91, p <.001). In total, 17.0% of the autistic group had deliberately self-harmed recently, compared to 3.6% of the non-autistic group. The autistic group were five times more likely than the non-autistic comparison group to have deliberately self-harmed in the last year. However, when accounting for the influence of current symptoms of depression, autism group was no longer a significant predictor of recent self-harm (R 2 =.112, F=24.88, p <.001; depression b =.32, autism group b =.03) . See Table 2. Methods of Deliberate Self-Harm Among those who had deliberately self-harmed, no statistically significant differences were found, with comparable rates of self-harming methods being reported by the autistic and non-autistic groups. See Table 3 for frequencies of self-harming behaviours between groups. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - TABLE 3 (HARM TYPES) ABOUT HERE - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Suicidal Self-Harm The autistic group self-reported significantly higher rates of suicidal self-harm in comparison to the non-autistic group (χ 2 =22.84, p <.001). In total, 20.2% of the autistic group had engaged in suicidal self-harm, in comparison to 3.6% of the non-autistic group. The autistic group were nearly seven times more likely to engage in suicidal self-harm than the non-autistic group. The pattern of results remained when accounting for the influence of current depression symptoms (R 2 =.101, F=21.99, p <.001; depression b =.23, autism group b =.12) . See Table 2. When examining the overlap between suicidal ideation and suicidal self-harm, 26% of autistic individuals who had experienced suicidal ideation also engaged in suicidal self-harm, in comparison to 14% of non-autistic individuals. This difference was significant (χ 2 =43.42, p <.001) with a medium effect size (Cramer’s v= .34). Gender Differences in Self-harm and Suicidality When comparing the experience of autistic women to autistic men, our analyses indicated that autistic women self-reported significantly higher rates of suicidal ideation (women: 77.4% vs. men: 67.0%, respectively; χ 2 =9.78, p =.008), thoughts of self-harm (74.2% vs. 56.4%; χ 2 =9.64, p =.008), deliberate self-harm (62.1% vs. 44.7%; χ 2 =6.54, p =.011) and suicidal self-harm (26.6% vs. 11.7%; χ 2 =7.38, p =.007) when compared to autistic men; however, no statistical differences were found between autistic women and autistic men in recent thoughts of self-harm or recent deliberate self-harm. When considering the frequency of these experiences, autistic women were found to have more frequent thoughts of suicidal ideation (8.9% once, 68.5% more than once) when compared to autistic men (18.6% once, 48.4% more than once), as well as more frequent of thoughts of harm (autistic women: 12.1% once, 61.1% more than once; vs. autistic men:14.9% once, 41.5% more than once), but not in the frequency of deliberate harm. Few gender differences were found in the non-autistic group, with only rates of suicidal ideation reaching statistical significance (non-autistic women: 32.9% vs. non-autistic men: 19.0%; χ 2 =8.80, p= .012). The patterns of results remained when accounting for the influence of current depression symptoms. See Supplementary Table 1. For methods of self-harming behaviours, no statistical differences were found between autistic women and autistic men, with similar rates of each method of harm being used. This sub-group analysis was not conducted in the non-autistic group due to low endorsement of suicide experiences resulting in low statistical power. See Supplementary Table 2. Age Differences in Self-harm and Suicidality in the Autistic group When comparing the experience of autistic people in midlife (ML; i.e., aged 40-64 years) and old age (OA; i.e., aged 65+ years), our analyses indicated that autistic people in old age self-reported significantly higher rates of self-harming thoughts (OA: 76.1% vs. ML: 60.0%; χ 2 =6.20, p =.043), deliberate self-harm (OA: 70.5% vs. ML: 43.8%; χ 2 =14.98, p <.001), recent deliberate self-harm (OA: 23.9% vs. ML: 12.3%), and suicidal self-harm (OA: 28.4% vs. ML: 14.6%; χ 2 =4.97, p =.026) when compared to autistic people in midlife; however, no statistical differences were found between autistic people in midlife and old age in suicidal ideation (ML: 68.7% vs. OA: 79.5%). %). When considering the frequency of these experiences, autistic people in old age were found to have more frequent thoughts of thoughts of harm (OA: 60.2% more than once, vs. ML: 48.5% more than once), but not in the frequency of suicidal ideation or deliberate harm. The patterns of results in thoughts of harm, deliberate self-harm and suicidal self-harm remained when accounting for the influence of current depression symptoms, however, age group as a predictor of recent thoughts of harm and recent deliberate self-harm were no longer statistically significant after controlling for depression. See Supplementary Table 3. For methods of self-harming behaviours, autistic people in midlife were statistically more likely to self-injure through cutting, scratching or hitting compared to the autistic people in midlife (ML: 75.4% vs. OA 49.2%; χ 2 =8.71, p =.003), while the autistic people in old were more likely to self-injure by ingesting medications more than the norma dosage (OA: 59.7% vs. ML: 38.6%; χ2=5.28, p =.0.22) or by swallowing dangerous objects or products (OA: 30.6% vs. ML: 14.0%; χ 2 =4.67, p =.031). No other statistical differences were found. See Supplementary Table 4. DISCUSSION Using data from a sample of people in midlife and older age, this study provides evidence that middle-aged and older autistic adults self-report higher rates and frequencies of self-harm and suicidality than age- and sex-matched non-autistic comparisons, including when accounting for current symptoms of depression. Some gender differences were observed, with autistic women reporting higher rates and frequencies of suicidal ideation and higher rates of suicidal self-harm than autistic men. Additionally, autistic adults in older age had higher rates of deliberate self-harm, including suicidal self-harm, than autistic adults in midlife. These findings – which broadly replicate and extend Stewart et al.’s ( 2023 ; 31) results from a high autistic trait (not diagnosed) sample – contributes valuable information about suicidality in autistic people in midlife and older age, a demographic that has historically been overlooked. The first key finding in the current study was that the autistic participants in midlife and older age self-reported significantly higher rates of suicidal ideation and self-harming thoughts than non-autistic comparisons The autistic group were also significantly more likely to have a higher frequency of these problems, with 60% having experienced suicidal ideation more than once. Our findings align with previous research, such as a UK-based clinical cohort study by Cassidy et al., ( 2014 ; 16), which reported that 66% (n = 243) of autistic adults had contemplated suicide. Additionally, comparable rates were also found in Stewart et al., ( 2023 ; 31), which found that 73% of middle-aged and older adults with high autistic traits had experienced suicidal ideation. While suicidal ideation and thoughts of self-harm were not uncommon in the non-autistic group, the autistic group were six to eight times more likely to have had these experiences, highlighting that suicidality is a pressing health issue in autistic populations. When considering why rates and frequencies of suicidal ideation may be so high in autistic populations, mental health challenges likely play a key role. Autistic individuals show higher prevalence rates for nearly all mental health conditions compared to non-autistic counterparts (8–9, 42). Mental health problems are also of concern in the current study, with the autistic group being found to report significantly higher depression symptom scores than the non-autistic group. There is a growing body of research as to why autistic people often have more mental health problems than the general population (e.g., social isolation, social stigma, victimisation and trauma, rigid cognitive style, and poorer normative outcomes; 27, 43), which in turn may exacerbate feelings of hopelessness, which is a core feature of suicidal ideation and may lead to periods of suicidal crisis (18, 21, 44). This interaction between autism, biopsychosocial risk factors, and suicidal ideation suggests a complex interplay of factors. While our current study did account for depression in our analyses (with the pattern of results remaining unchanged) further investigation of the influence of depression and other risk factors is needed. Another key finding of this study was the significantly higher rates of deliberate self-harm reported by the autistic group, where over half of the autistic participants had engaged in self-harm. Of those who had harmed, approximately three-quarters of the autistic group had deliberately self-harmed three or more times. This finding is consistent with previous research showing that a significant proportion of autistic individuals (50–65%) engage in deliberate self-harm (18, 19, 21). However, this rate of harm is notably higher than the 20% rate reported by Stewart et al. ( 2023 ); this difference could be attributed to study design differences (i.e., convenience sampling vs. large-scale longitudinal study of healthy ageing), sampling differences (e.g., diagnosed/self-identified autistic people vs. those with high autistic traits), and that some self-harming behaviours (e.g., hitting, scratching) may be stimming behaviours that autistic people engage in for therapeutic reasons (45). When considering the high rates reported in the current study and other studies involving autistic people with a diagnosis, several factors may play an important role in why autistic people self-harm. For some autistic individuals, self-harm may serve as a coping mechanism to regulate sensory overload or express unmet emotional needs (46). Late autism diagnoses may also contribute to higher rates of self-harm, as individuals with a late diagnosis may experience greater social difficulties, mental health issues, and frustration due to the delayed recognition of their condition (47–50). This may lead to feelings of perceived burdensomeness and thwarted belongingness, which are central to the Interpersonal Theory of Suicide (36). The interplay between these factors may help explain the heightened rates of suicidal ideation and behaviour observed in the autistic population. The third key finding showed that middle-aged and older autistic adults also self-reported higher rates of suicidal self-harm than non-autistic adults. The rates of these experiences in the current study are higher than those documented in previous research (17% of autistic and 4% of non-autistic participants), for example, Hirvikoski et al. ( 2020 ; 22) and Stewart et al. ( 2023 ; 31) report that 8–13% of autistic / high autistic trait adults experience suicidal self-harm. This discrepancy may be influenced by the focus on middle-aged and older adults (i.e., lifetime experiences are likely to increase with age) or reflect the current study's sample size (although well powered), convenience sampling approach (although predominately recruited through large and well-established autism research networks), or potential self-report biases (51). When thinking more broadly about why people may harm themselves with the intention of suicide, many factors may play an important role, which may be particularly impactful for autistic people (52–53). In the general population, adults in relationships and in employment have lower suicide rates (54), including autistic adults (18, 44); these lower rates are likely due to increased social connectedness and support. Furthermore, autistic adults with unmet social support needs also have lower suicide rates (18). While suicidal ideation does not always lead to suicidal behaviour, the significantly higher rates of co-occurring ideation and self-harm in autistic adults highlights the need for interventions that have been specifically designed to support autistic people, for example tailored mental health support, ensuring autistic people have opportunities for support employment, as well as social opportunities to develop relationships with others. Our gender-based analyses also yielded important information when considering the experiences of suicidality in autistic populations. The autistic women in midlife and older age in our current study reported almost three times higher rates of self-harm and suicidality than the autistic men. This pattern of results mirrors that in the general population. When considering why autistic women may have such high rates of suicidality compared to autistic men, increased masking/camouflaging, later diagnosis, co-occurring mental health conditions, and societal pressures may disproportionately affect autistic women (55). These factors may contribute to the feelings of thwarted belongingness and perceived burdensomeness that are central to suicidality according to the interpersonal theory of suicide, which has been applied to the general and autistic populations (36, 56–58). Previous research has consistently found similar gender disparities to our study, with autistic women at higher risk for suicidal thoughts and behaviours compared to autistic men (18, 26). Taken together, these gender differences highlight the importance of adopting gender-sensitive approaches in both clinical practice and research. Finally, our age-related analyses also provided important insight into potential vulnerabilities of autistic adults in older age (i.e., over 65 years old). Older autistic adults were found to report higher rates of self-harming thoughts, deliberate self-harm, and suicidal self-harm when compared to autistic adults in midlife (i.e., 40–64 years old). While our questions often captured lifetime experiences (which likely increase with age), higher rates of recent self-harm were also found to be reported by the older autistic participants. These findings suggest that age-specific factors contribute to heightened self-harm risks in older populations, potentially due to increased social isolation (35, 50) and barriers to adequate healthcare support (59), warranting age-tailored interventions. Furthermore, the middle-aged autistic adults were more likely to self-injure through cutting, scratching, or hitting, while the older autistic adults were more likely to ingest medication overdoses or other dangerous objects/products indicating variations in self-harm methods across age groups. This highlights the importance of understanding age-related differences in clinical settings to better support autistic individuals throughout their lifespan. The findings of the current study have significant clinical implications. While suicidality cannot be directly 'treated', interventions can address underlying risk factors. There is a clear need for tailored screening tools, gender-sensitive approaches, and age-appropriate interventions for autistic adults. Promoting social connection, mitigating perceived burdensomeness, and reducing stigma should be key components of suicide prevention strategies. Implementation of the 2009 Autism Act (60) and enhanced professional training for adult service providers remains crucial. Training is essential to equip providers to support the complex needs of the often-underserved older autistic population (61). Future research priorities should include longitudinal studies to track changes in suicidality over time and development of comprehensive assessment tools (62). Additionally, future studies should examine the experiences of autistic people from gender minorities (e.g., trans and non-binary people), a group also known to be vulnerable to suicidality (63–64). Finally, autistic people must be consulted when studying suicidality, to ensure the studies are conducted in a way sensitive to their experiences and to not cause unforeseen harm. Strengths and Limitations When contextualising the findings of the current study, several strengths and limitations are worth considering. For strengths, this study conducted extensive PPI interviews and project steering, which ensured topic relevance and accessibility. The breadth of survey topics likely reduced recruitment bias toward those with experiences of suicidality, increasing the generalisability of our findings. Additionally, diverse recruitment methods (e.g., online adverts, notices shared through large and well-established autism research networks, community centre notices) enhanced sample representativeness and includes older people who are potentially not actively using the internet and social media. Our sample was also well matched on key demographic factors, with almost half of the participants being men and the sample including those in later life (i.e., over the age of 80). However, limitations must be acknowledged. The AgeWellAutism study was conducted online, and there has been a well-documented increase in the number of threats to data integrity due to spam and imposter participants (65). However, many of these issues arose after the COVID-19 pandemic, and the current study was conducted in Spring 2019. Another consideration is that this study relies on self-report, which may limit clinical accuracy and may not fully capture autistic experiences, particularly for individuals with language difficulties or intellectual disabilities. Furthermore, the cross-sectional study design does not allow for causal inferences to be made (66). And finally, potential survivor bias may skew data by predominantly representing healthier older adults and excluding critical insights from individuals who died by suicide that can only be gained through mortality reports (67–68). While these limitations may restrict the overall generalisability of the findings, the results offer valuable insights into self-reported self-harm and suicidality experiences of autistic adults in midlife and older age. This study represents a critical step towards an enhanced understanding of suicidality in ageing autistic populations and highlights the need for tailored support to mitigate the risk of suicide in this population. CONCLUSION This study provides important clinical insights regarding patterns in suicidality and suicidal behaviours in middle-aged and older autistic adults. First, middle-aged and older autistic adults demonstrate significantly higher rates of self-harm and suicidal behaviours compared to non-autistic peers. Second, notable gender differences exist, with autistic women showing heightened risk across all suicidality and suicidal self-harm items, highlighting the need for gender-sensitive approaches in assessment and intervention. Third, our findings emphasise the persistence and exacerbation of suicide risk into middle and older age, with older autistic adults reporting higher rates of lifetime and recent suicidality and suicidal self-harm behaviours, underlining the need for life-course approaches to suicide prevention. Taken as a whole, our findings represent a significant contribution to our understanding the rates of suicidality in autistic adults. Moving forward, it is crucial to consider gender and age-related differences in suicidality research, and to also consider potential mechanisms underpinning suicidality in autistic populations. By doing this, clinicians will be better equipped to support autistic people, including those in midlife and older age. Abbreviations RAADS-14: Ritvo Autism and Aspergers Diagnostic Scale, a measure of autistic traits PHQ-8/9: Patient Health Questionnaire, a measure of depression ANOVA: Analysis of Variance, statistical test to analyse difference between means of two or more groups Declarations ETHICAL APPROVAL Full ethical approval was granted by the PNM Research Ethics Subcommittee at King's College London (HR-18/19–10941). Written, online informed consent was obtained from all participants, and research was conducted in accordance with the Declaration of Helsinki. CONSENT FOR PUBLICATION Participants provided written informed consent for the publication of anonymised data as part of the consent process when agreeing to take part in the online study. AVAILABILITY OF DATA AND MATERIALS The data that support the findings of this study are held by Dr. Gavin Stewart, but the availability of these data is restricted. The data were used under license for the current study and are not publicly available. However, the data may be available from the authors upon reasonable request and with permission from Dr. Gavin Stewart. COMPETING INTERESTS None to declare. ACKNOWLEDGEMENTS The authors are grateful to the 12 autistic people who offered suggestions on content and provided feedback on the language-use and accessibility of the study materials. FUNDING At the time of data collection, GRS was funded by an UKRI/ESRC LISS-DTP PhD studentship (ES/P000703/1). GRS is currently funded by a British Academy Postdoctoral Research Fellowship (PFSS23\230043). FH is part-funded by the NIHR Maudsley Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King’s College London. The funders have had no role in the data collection, analysis, interpretation, or any other aspect pertinent to the study. The authors have not been paid to write this article by any agency. This paper represents independent research conducted by the authors, and the views expressed are those of the author(s) and not necessarily those of the BA, NIHR, NHS or KCL. AUTHOR’S CONTRIBUTIONS Authors FH, RAC and GRS conceived the AgeWellAutism study. GRS designed the online survey and selected materials. GRS conceived the current study. SR and GRS conducted analyses. SR wrote the manuscript under the supervision of GRS. FH and RAC reviewed the final draft. All authors have read and approved the final manuscript. References Office for National Statistics: Suicides in England and Wales: 2023 registrations. https://www.ons.gov.uk/peoplepopulationandcommunity/birthsdeathsandmarriages/deaths/bulletins/suicidesintheunitedkingdom/2023 (2024). Accessed 29 Aug 2024. 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Autistic (n=222) Non-Autistic (n=166) Group Difference Effect Size Age (years) M (SD) 60.89 (12.84) 60.55 (13.58) t(386) =.247 p= .805 n/s d =0.03 [-0.23, 0.18] [95% CI] [59.18, 62.59] [58.47, 62.64] Range 40-91 40-93 Gender N men : women 98 : 124 84 : 82 χ 2 =1.59, p =.207 n/s v =.06 % 44.1% : 55.9% 50.6% : 49.4% Living Situation Spouse or partner 85 (38.3%) 79 (47.6%) χ 2 =3.37, p= .066 n/s v =.09 Children 62 (27.9%) 39 (23.5%) χ 2 =0.97, p =.325 n/s v =.05 Sibling 24 (10.8%) 0 – χ 2 =19.13, p <.001*** v =.22 Parent 19 (8.6%) 7 (4.2%) χ 2 =2.86, p =.09 n/s v =.09 Other family member 7 (3.2%) 0 – χ 2 =5.33, p =.021* v =.12 Roommate/friend 20 (9.0%) 12 (7.2%) χ 2 =0.40, p= .528 n/s v =.03 Supported Housing 38 (17.1%) 20 (12.0%) χ 2 =1.92, p =.166 n/s v =.07 Alone/Independently 41 (18.5%) 57 (34.3%) χ 2 =12.67, p< .001*** v =.18 Education Level No formal qualifications 23 (10.4%) ǂ 4 (2.4%) ǂ χ 2 =16.97 p =.002** v =.21 School to 16 50 (22.5%) 27 (16.3%) School to 18 61 (27.5%) ǂ 65 (39.2%) ǂ Undergraduate 54 (24.3%) 51 (30.7%) Postgraduate 34 (15.3%) 19 (11.4%) Employment Status Employed 69 (31.1%) ǂ 87 (52.4%) ǂ χ 2 =35.04 p <.001*** v =.30 Unemployed 24 (10.8%) ǂ 3 (1.8%) ǂ Unable to work due to health 24 (10.8%) ǂ 2 (1.2%) ǂ Retired 105 (47.5%) 74 (44.6%) Autism Diagnosis/Identification Diagnosed 211 (95.1%) Self-Identified 11 (4.9%) - Years since Autism Diagnosis/Identity M (SD) 9.42 (7.66) - - Range (years) 0-43 - - - Autism Traits (max score=42) M (SD) 32.74 (7.53) 2.95 (4.07) t (386)=49.96, p <.001*** d =4.74 [4.07, 7.53] Note. N=388. d =Cohen’s d. v =Cramer’s v. * p <.05, ** p <.01. *** p <.001 Table 2. Self-reported prevalence rates of self-harm and suicidality in the Autistic and Non-Autistic groups. Autistic (n=222) Non-Autistic (n=166) Group Difference Effect Size Odds Ratio Suicidal Ideation - Many people have felt that life is not worth living. Have you felt that way? No 59 (26.9%) ǂ 123 (74.1%) ǂ χ 2 =129.84, p <.001*** v =.58 7.85 [4.97, 12.41] Yes, once 29 (13.2%) ǂ 36 (21.7%) ǂ Yes, more than once 131 (59.8%) ǂ 7 (4.2%) ǂ Thoughts of Harm - Have you contemplated harming yourself (for example by cutting, biting, hitting yourself or taking an overdose)? No 73 (33.5%) ǂ 124 (74.7%) ǂ χ 2 =85.67, p <.001*** v =.47 5.90 [3.77, 9.25] Yes, once 29 (13.3%) 27 (16.3%) Yes, more than once 116 (53.2%) ǂ 15 (9.0%) ǂ Thoughts of Harm (Recent) - Have you contemplated harming yourself in the last 12 months? No 123 (56.4%) 157 (94.6%) χ 2 =69.48, p <.001*** v =.43 13.47 [6.54, 27.77] Yes 95 (43.6%) 9 (5.4%) Deliberate Harm - Have you deliberately harmed yourself, whether or not you meant to end your life? No 99 (45.0%) 144 (86.7%) χ 2 =69.29, p <.001*** v =.43 7.86 [4.67, 13.26] Yes 121 (55.0%) 22 (13.3%) Frequency of Harm – If yes, how many times have you harmed yourself? Once 18 (14.9%) ǂ 13 (54.2%) ǂ χ 2 =22.62, p <.001*** v =.40 - Twice 13 (10.7%) ǂ 6 (25.0%) ǂ Three or more times 90 (74.4%) ǂ 5 (20.8%) ǂ Deliberate Harm (Recent) - Have you harmed yourself in the last 12 months, whether or not you meant to end your life? No 181 (83.0%) 160 (96.4%) χ 2 =16.91, p <.001*** v =.21 5.41 [2.24, 13.25] Yes 37 (17.0%) 6 (3.6%) Suicidal Harm - Have you deliberately taken an overdose or harmed yourself with the intention to end your life? No 174 (79.8%) 160 (96.4%) χ 2 =22.84, p <.001*** v =.24 6.74 [2.80, 16.25] Yes 44 (20.2%) 6 (3.6%) Note. ǂ Adjusted residual indicates proportional difference. Odds ratios calculated with yes/frequency options grouped. * p <.05, ** p <.01. *** p <.001 Table 3. Self-reported types of harm used by those who have self-harmed. Autistic (n=116) Non-Autistic (n=22) Group Difference Effect Size Types of Harm – Have you done any of the following to harm or endanger yourself? Stopping prescribed medication 21 (18.1%) 3 (13.6%) χ 2 =0.28, p =.612 n/s v =.04 Swallowing dangerous objects or products 27 (22.7%) 1 (4.5%) χ 2 =3.84 p =.050 n/s v =.17 Ingesting alcohol or recreational/illicit drug 28 (23.7%) 3 (13.6%) χ 2 =1.10, p =.295 n/s v =.09 Ingesting a medication more than the normal dosage 59 (49.6%) 11 (50.0%) χ 2 =0.01, p =.971 n/s v <.01 Self-injury (e.g., cutting, scratching, hitting) 74 (61.7%) 10 (45.5%) χ 2 =2.02, p =.155 n/s v =.12 Note. Participants could select multiple options, thus total does not equal 100%. Additional Declarations No competing interests reported. Supplementary Files SupplementaryTables.docx APPENDICES.docx Cite Share Download PDF Status: Published Journal Publication published 25 Nov, 2025 Read the published version in Molecular Autism → Version 1 posted Editorial decision: Revision requested 11 Jul, 2025 Reviews received at journal 27 May, 2025 Reviewers agreed at journal 16 May, 2025 Reviews received at journal 03 May, 2025 Reviewers agreed at journal 28 Apr, 2025 Reviewers agreed at journal 28 Apr, 2025 Reviewers invited by journal 28 Apr, 2025 Editor assigned by journal 25 Apr, 2025 Submission checks completed at journal 24 Apr, 2025 First submitted to journal 23 Apr, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6511234","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":450127914,"identity":"424cd772-c109-4632-81ab-0ca54e37bb5a","order_by":0,"name":"Sophie Roper","email":"","orcid":"","institution":"King’s College London","correspondingAuthor":false,"prefix":"","firstName":"Sophie","middleName":"","lastName":"Roper","suffix":""},{"id":450127915,"identity":"32de725e-8318-4dfd-a1e9-a609b095cd94","order_by":1,"name":"Rebecca Charlton","email":"","orcid":"","institution":"Goldsmiths University of London","correspondingAuthor":false,"prefix":"","firstName":"Rebecca","middleName":"","lastName":"Charlton","suffix":""},{"id":450127916,"identity":"18fb49ea-5f3e-4de8-bd54-31ae11ca394a","order_by":2,"name":"Francesca Happé","email":"","orcid":"","institution":"King’s College London","correspondingAuthor":false,"prefix":"","firstName":"Francesca","middleName":"","lastName":"Happé","suffix":""},{"id":450127917,"identity":"34dc9d35-3a85-49d7-a7ae-cac80a9a8701","order_by":3,"name":"Gavin R. Stewart","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA/ElEQVRIiWNgGAWjYJCCAwhmRQIDH4SVQFCLBIR1JoGBjRgtDHAtB9uI0CLvfsbwcAFDXR2/RPKzzx/npcmzMTA//MDYloZTi+GZHIPDMxgOS0jOSDOecXBbjmEbA5uxBGNbDm4tDWkJh3kYDkgY3E4wZji4rSIB6DAzBsa2Ctxa+p+BtNRJ2N9O/8xwcA5IC/s3vFrkJZIPALUwSxhI5wBtacgBauEB2YLbYQYSj4FaDA5Lzrj/ppjhzLE0wzZmnmKJhHO4vS/fn9j8maeijp+/5/hmhoqaZHl+9vaNHz6UJeO25QCYRBZiZsAfkfINeCRHwSgYBaNgFIABAA9bTUokG2C4AAAAAElFTkSuQmCC","orcid":"","institution":"King’s College London","correspondingAuthor":true,"prefix":"","firstName":"Gavin","middleName":"R.","lastName":"Stewart","suffix":""}],"badges":[],"createdAt":"2025-04-23 09:38:31","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6511234/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6511234/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s13229-025-00693-x","type":"published","date":"2025-11-25T15:57:22+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":97178334,"identity":"176f9544-c200-4723-83de-2e051cbe2828","added_by":"auto","created_at":"2025-12-01 16:08:09","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1280229,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6511234/v1/7dc8bccc-d7ed-4475-abb1-4fadc6d6b711.pdf"},{"id":81915230,"identity":"fd7f0cf3-6025-478b-8e96-d19344c0e9c0","added_by":"auto","created_at":"2025-05-04 17:17:37","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":28514,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementaryTables.docx","url":"https://assets-eu.researchsquare.com/files/rs-6511234/v1/0b8b4682bf190b232a558069.docx"},{"id":81915229,"identity":"7723ab7e-124c-42f7-a9a1-2a4d84c5fcd2","added_by":"auto","created_at":"2025-05-04 17:17:36","extension":"docx","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":16869,"visible":true,"origin":"","legend":"","description":"","filename":"APPENDICES.docx","url":"https://assets-eu.researchsquare.com/files/rs-6511234/v1/d99fcfc958259737fd0aff2c.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Self-Harm and Suicidality Experiences of Autistic and Non-Autistic Adults in Midlife and Older Age","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eSuicidality \u0026ndash; an umbrella term for suicidal ideation, thoughts of harm, deliberate harm, suicide plans, harming with the intention of suicide, and death by suicide \u0026ndash; is a global public health concern, with suicide accounting for 11.4 deaths per 100,000 people in the UK (1). While women are more often found to self-harm, death by suicide occurs more commonly among men than women at a ratio of 3.5 to 1, with men often using more lethal methods of suicide (2). While death by suicide has been recorded at all ages, high incidence rates of suicide in the UK are often found in midlife (age 40\u0026ndash;64 years), which then peak in older age (64 years and older) (1). Many factors have been attributed to this spike in later life, such as age-related change to health and cognition, and social factors (3). Despite this peak in incidence of suicidality in midlife and older age, few studies have explored whether populations known to be at high risk of suicide, for example autistic people, have increased rates of suicidality in this later age-range.\u003c/p\u003e \u003cp\u003eAutism is a lifelong neurodevelopmental condition affecting approximately 1% of the global population (4). Characterised by differences in social communication and rigid-repetitive behaviours and interests, autism plays a significant role in shaping individuals' experiences throughout their lives (5\u0026ndash;6). Autistic adults often experience poorer physical and mental health, lower education rates, lower employment rates, higher rates of traumatic events, more sleep disturbances, and lower overall quality of life (7\u0026ndash;14). These negative outcomes may be relevant to the high rates of suicidality compared to non-autistic people (15). Multiple studies, including those using extensive population registers (from countries such as Australia, Korea, France, Sweden, Taiwan and the UK) and genetically informed designs (e.g., UKBioBank), have consistently shown that autistic people are at a heightened risk for suicidal ideation (15\u0026ndash;17), non-suicidal self-harm (17\u0026ndash;20), suicidal self-harm (17, 21\u0026ndash;23), and death by suicide (22, 24\u0026ndash;26). Estimates pooled from 36 primary studies involving over 46,000 autistic people (age means\u0026thinsp;=\u0026thinsp;10 to 42 years) suggest that approximately 34% of autistic people have experienced suicidal ideation, 22% have considered plans for suicide, and 24% have harmed themselves with the intention of suicide (15). Suicide has also been found to be a leading cause of premature death in autistic people (ranked third in a Swedish population-based study, accounting for 12% of deaths in a sample of autistic decedents; 24), with autistic people being up to nine times more likely to die by suicide compared to the general population (27). Additionally, unlike in the general population, death by suicide is found to be higher in autistic women than autistic men, highlighting an important consideration for how suicidality is identified and risk assessed autistic populations (26).\u003c/p\u003e \u003cp\u003eWhen considering suicidality in autistic populations in midlife and older age, information is sparse. Despite population estimates suggesting that there are upwards of 250,000 autistic people in the UK over the age of 50 (28), research on middle-aged and older autistic adults accounts for only 0.4% of indexed autism research since 1980 (29\u0026ndash;30). To the authors\u0026rsquo; knowledge, only one study to date has specifically explored suicidality in midlife and older age in relation to autism. Stewart et al. (\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; 31), utilising a dimensional trait-based approach to account for high rates of underdiagnosis in midlife and older populations (28), showed that adults with high autistic traits (n\u0026thinsp;=\u0026thinsp;276, aged 50\u0026ndash;81, 31% men) self-reported significantly higher rates of suicidal ideation (72.7% vs. 29.3%), deliberate self-harm (19.9% vs. 4.7%) and suicidal self-harm (12.7% vs. 2.5%) when compared to age and gender-matched low autistic trait individuals (n\u0026thinsp;=\u0026thinsp;10,495); these higher rates represented a five-to-six-fold increase in the likelihood of suicidality for the high autistic trait participants. Importantly, this pattern remained when accounting for symptoms of depression.\u003c/p\u003e \u003cp\u003eWhen considering possible reasons why middle-aged and older autistic people may have high rates of suicidality, delayed diagnosis and lack of support may play a key role (32\u0026ndash;33). Additionally, middle-aged and older autistic people often experience high rates of social isolation and low social support (34\u0026ndash;35). These issues fit with the proposed \u0026lsquo;Interpersonal Theory of Suicide\u0026rsquo; (36), which offers a valuable framework for understanding why autistic individuals may face heightened suicide risks, emphasising factors like perceived burdensomeness and thwarted belongingness.\u003c/p\u003e \u003cp\u003eDespite growing research on autism and suicidality, there remains a significant gap in our understanding of how these issues manifest and change throughout the lifespan, especially in mid-to-late adulthood. This study seeks to replicate and extend the findings of Stewart et al.\u0026rsquo;s (\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; 31) trait-based study in a similarly aged sample of autistic adults who have a diagnosis of autism or who self-identify as autistic. We hypothesise that a similar pattern of results will be found in our diagnosed/self-identified autistic sample, namely that: 1) middle-aged and older autistic adults will self-report higher rates of suicidal ideation, self-harming thoughts, deliberate self-harm, and suicidal self-harm than age-and-sex matched non-autistic adults; 2) autistic women will report higher rates of suicidality than autistic men; 3) autistic adults aged 65+ (i.e., older adults) will report more experiences of suicidality than autistic adults aged 40\u0026ndash;64 years (i.e., middle-aged adults).\u003c/p\u003e"},{"header":"METHODS","content":"\u003cp\u003e\u003cstrong\u003eStudy Design\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study uses cross-sectional data from the first wave of the \u0026lsquo;AgeWellAutism\u0026rsquo; study, conducted in Spring 2019. The AgeWellAutism study is an online survey investigating ageing on the autism spectrum (outlined in Stewart et al., (2024; 35)). In brief, the content of the AgeWellAutism study was steered by 12 middle-aged and older autistic adults prior to launch, with recruitment being conducted through social media platforms (i.e., Twitter, Reddit, Facebook), participant databases managed by the author and Autistica\u0026apos;s Research Network, and adverts in community centres and older adult residential communities. An incentive of entry into a raffle for a \u0026pound;20 Amazon UK gift voucher was offered. Inclusion criteria were being 40 years of age or above, having access to an internet-enable device, and being able to read and type in English. The study had no specific exclusion criteria. Full ethical approval was granted by the PNM Research Ethics Subcommittee at King\u0026apos;s College London (HR-18/19\u0026ndash;10941).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eParticipants\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn total, 502 completed surveys were recorded, with 70 responses being removed due to suspected spam (i.e., very short completion times and/or irregular answers to open-text boxes). For the current study, a further 40 responses were excluded as these individuals opted to skip the self-harm and suicidality questions. An additional four non-binary/trans/agender participants were also omitted due to the small sample size. This resulted in a final sample of 388 participants aged 40-93 years. Participants who disclosed that they either had an autism diagnosis (n=211) or self-identified as autistic (n=11) formed an autistic group (n=222); both subgroups had comparable autistic trait scores (\u003cem\u003et\u003c/em\u003e(1,223)=1.63, \u003cem\u003ep\u003c/em\u003e=.104). The autistic group were asked when they received their autism diagnosis/ began to identify as autistic; responses ranged from as recently as the year of survey completion to 43 years ago (mean years since diagnosis=9.4 years), with nine (4.1%) diagnosed in childhood (i.e., prior to 18 years of age). The remaining participants formed the non-autistic group (n=166). The autistic and non-autistic groups were matched on age (autistic mean age=60.9 years; non-autistic mean age=60.6 years) and gender ratio (autistic group men=44.1%; non-autistic group men=50.6%). Both groups were comparable in education level and in country of residence, with around 98% living in the UK. However, the autistic sample self-reported lower employment rates and a higher likelihood of living with non-marital family members. No data on socio-economic status and race/ethnicity was collected. See Table 1 for demographic characteristics of the autistic and non-autistic groups.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTABLE 1 (DEMOGRAPHICS) ABOUT HERE\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMaterials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eDemographic Characteristics\u0026nbsp;\u0026ndash;\u0026nbsp;\u003c/em\u003eParticipants provided detailed self-reported demographic information, including age, gender, highest educational attainment, employment status, who they live with, and country of residence.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAutism Diagnoses/Self-identification and Autistic Traits - Participants were asked whether they had an autism diagnosis or if they self-identified as autistic. If yes, they were then asked how many years had passed since their diagnosis or they began to self-identify.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAdditionally, the\u0026nbsp;Ritvo Autism and Asperger Diagnostic Scale (RAADS-14; 37) was used to descriptively explore autistic trait endorsement in each group, to ensure the diagnosed and self-identified autistic participants could be combined into one group. The RAADS-14 is a 14-item questionnaire that explores autistic traits related to mentalising difficulties, sensory reactivity, and social anxiety. Scores range from 0-42, with a score \u0026ge;14 having a sensitivity of 97% and specificity of 46%-64% for identifying autism. The RAADS-14 has demonstrated satisfactory psychometric properties (38). In the current study, the RAADS-14 showed very good internal consistency in the autistic group (Cronbach\u0026rsquo;s \u003cem\u003ea=\u003c/em\u003e.887), and good consistency in the non-autistic group (Cronbach\u0026rsquo;s \u003cem\u003ea=\u003c/em\u003e.744).\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eSelf-Harm and Suicidality \u0026ndash;\u003c/em\u003e Experiences of suicidality were measured using the 8-item self-report UK BioBank Self-Harm and Suicidality Questionnaire (31). These questions were presented on an opt-in basis, with the option to skip questions at any point during the block.\u0026nbsp;Suicidal ideation was assessed by asking participants if they: 1) had felt that life was not worth living. For thoughts of harm, participants were asked whether they: 2) had contemplated harming themselves, and whether they: 3) had contemplated harming themselves in the last 12 months. For deliberate harm, frequency of harm, and types of harm, participants were asked: 4) if they had ever deliberately harmed themselves, whether they meant to end their life or not; 5) how many times they had deliberately harmed themselves; 6) if they had deliberately harmed themselves within the last 12 months; and 7) the types of harming behaviours used. For suicidal harm, participants were asked if they: 8) had deliberately taken an overdose or harmed themselves with the intention to end their life. For the complete list of questions and scoring matrix see supplementary materials.\u003c/p\u003e\n\u003cp\u003eThe UK BioBank Self-Harm and Suicidality questionnaire has been used in samples previously, including in older adults with high autistic traits (31). In the current study, the scale has very good internal consistency in the autistic (Cronbach\u0026rsquo;s \u003cem\u003ea\u003c/em\u003e=.807) and non-autistic (Cronbach\u0026rsquo;s \u003cem\u003ea\u003c/em\u003e=.849) groups.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eDepression\u003c/em\u003e \u0026ndash; Symptoms of depression were measured using the Patient Health Questionnaire (PHQ-8; 39). The PHQ-8 is an eight-item questionnaire with a 4-point scale which asks the participant to report whether they have been bothered by a range of problems over the past two weeks such as anhedonia, low mood, sleep problems, fatigue, poor appetite or weight change, concentration difficulty, and psychomotor disturbance. The PHQ-8 omits the suicidal ideation question included in the nine-item version of the measure (PHQ-9). Using the conventional cut-off score of \u0026ge;10, the PHQ-9 has a sensitivity of 88% and a specificity of 88% for major depressive disorder. The PHQ-9 has been validated for use in autistic adults (40).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Analysis\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe current study using the AgeWellAutism dataset (specifically hypotheses 1 and 2) was pre-registered prior to analyses being conducted (https://osf.io/qv23s). Hypothesis 3 (i.e., age-differences) was added as a post-hoc analysis and not included in the original pre-registration. All statistical analyses were performed using SPSS (v29.0.2.0; IBM Corp., 2023).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eDemographic variables and autism-related information was analysed with t-tests (continuous variables) and chi-squared tests (\u0026chi;\u0026sup2;; categorical variables). To address hypothesis 1, \u0026chi;\u0026sup2; analyses were conducted to investigate group differences (autistic vs. non-autistic) in rates of self-harm and suicidality experiences. A series of linear regressions (with suicidality items as outcomes, and autism group and depression scores as predictors) were conducted to examine whether any observed group differences in suicidality were solely a function of worse depression symptomology.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTo address hypothesis 2, additional layered \u0026chi;\u0026sup2; analyses were performed to examine differences in self-harm and suicidality scores by gender (men vs. women) and group (autistic vs. non-autistic). Adjusted residual values were checked for detecting significant differences in ratings or proportions.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTo address hypothesis 3, \u0026chi;\u0026sup2; analyses were conducted to investigate age group differences (middle-aged (40-64 years) vs. older age (65+ years)) in rates of self-harm and suicidality experiences in the autistic group; these analyses were not conducted in the non-autistic group due to small group sizes. Multiple comparisons were accounted for by using the False Discovery Rate method (FDR; 41), using an initial alpha level of .050. The FDR procedure was applied to all p-values, and adjusted alpha values were assigned based on the rank of the \u003cem\u003ep\u003c/em\u003e-values; final FDR adjusted critical value being .044.\u003c/p\u003e"},{"header":"RESULTS","content":"\u003cp\u003e\u003cstrong\u003eGroup Differences in Self-Harm and Suicidality\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eSuicidal Ideation\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe autistic group self-reported significantly higher rates and higher frequencies of suicidal ideation compared to the non-autistic group (\u0026chi;2=129.84, \u003cem\u003ep\u003c/em\u003e\u0026lt;.001). In total, 73.0% of the autistic group had experienced suicidal ideation (13.2% once, 59.8% more than once) in comparison to 25.9% of the non-autistic group (21.7% once, 4.2% more than once). The autistic group were almost eight times more likely than non-autistic group to have experienced suicidal ideation\u0026nbsp;at least once.\u0026nbsp;The pattern of results remained when accounting for the influence of current depression symptoms (R\u003csup\u003e2\u003c/sup\u003e=.346, F=105.54, \u003cem\u003e\u003cu\u003ep\u003c/u\u003e\u003c/em\u003e\u003cu\u003e\u0026lt;.001; depression \u003cem\u003eb\u003c/em\u003e=.25, autism group \u003cem\u003eb\u003c/em\u003e=.41)\u003c/u\u003e.\u0026nbsp;See Table 2.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTABLE 2 (RATES) ABOUT HERE\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eSelf-Harming Thoughts\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe autistic group self-reported significantly higher rates and higher frequencies of self-harming thoughts compared to the non-autistic group (\u0026chi;\u003csup\u003e2\u003c/sup\u003e=85.67, \u003cem\u003ep\u003c/em\u003e\u0026lt;.001). In total, 66.5% of the autistic group (13.3% once, 53.2% more than once) had experienced these thoughts, in comparison to 25.3% of the non-autistic group (16.3% once, 9.0% more than once). The autistic group were nearly six times more likely than the non-autistic group to have experienced self-harming thoughts at least once.\u0026nbsp;The pattern of results remained when accounting for the influence of current depression symptoms (R\u003csup\u003e2\u003c/sup\u003e=.277, F=75.14, \u003cem\u003e\u003cu\u003ep\u003c/u\u003e\u003c/em\u003e\u003cu\u003e\u0026lt;.001; depression \u003cem\u003eb\u003c/em\u003e=.31, autism group \u003cem\u003eb\u003c/em\u003e=.28)\u003c/u\u003e. See Table 2.\u003c/p\u003e\n\u003cp\u003eAdditionally, the autistic group self-reported significantly higher rates of self-harming thoughts within the last 12 months compared to the non-autistic group (\u0026chi;\u003csup\u003e2\u003c/sup\u003e=69.48, \u003cem\u003ep\u003c/em\u003e\u0026lt;.001). In total, 43.6% of the autistic group had contemplated self-harm recently, compared to 5.4% of the non-autistic group. The autistic group were thirteen times more likely than the non-autistic group to have experienced self-harming thoughts in the last year.\u0026nbsp;The pattern of results remained when accounting for the influence of current depression symptoms (R\u003csup\u003e2\u003c/sup\u003e=.265, F=70.68, \u003cem\u003e\u003cu\u003ep\u003c/u\u003e\u003c/em\u003e\u003cu\u003e\u0026lt;.001; depression \u003cem\u003eb\u003c/em\u003e=.37, autism group \u003cem\u003eb\u003c/em\u003e=.20)\u003c/u\u003e.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eDeliberate Self-Harm\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe autistic group self-reported significantly higher rates of deliberate self-harm compared to the non-autistic group (\u0026chi;\u003csup\u003e2\u003c/sup\u003e=69.29, \u003cem\u003ep\u003c/em\u003e\u0026lt;.001). In total, 55.0% of the autistic group had deliberately self-harmed, compared to 13.3% of the non-autistic group. The autistic group were nearly eight times more likely than the non-autistic comparison group to have deliberately self-harmed\u0026nbsp;at least once.\u0026nbsp;Among those who had deliberately self-harmed, the autistic group reported significantly higher frequencies of self-harm incidents than the non-autistic group\u0026nbsp;(\u0026chi;\u003csup\u003e2\u003c/sup\u003e=22.62, \u003cem\u003ep\u003c/em\u003e\u0026lt;.001). Of those who had deliberately self-harmed, 85.1% of the autistic group had two or more incidents of harm compared to 45.8% of the non-autistic group.\u0026nbsp;The patterns of results remained when accounting for the influence of current depression symptoms (R\u003csup\u003e2\u003c/sup\u003e=.279, F=76.09, \u003cem\u003e\u003cu\u003ep\u003c/u\u003e\u003c/em\u003e\u003cu\u003e\u0026lt;.001; depression \u003cem\u003eb\u003c/em\u003e=.37, autism group \u003cem\u003eb\u003c/em\u003e=.21)\u003c/u\u003e.\u0026nbsp;See Table 2.\u003c/p\u003e\n\u003cp\u003eAdditionally, the autistic group self-reported significantly higher rates of deliberate self-harm within the last 12 months compared to the non-autistic group (\u0026chi;\u003csup\u003e2\u003c/sup\u003e=16.91, \u003cem\u003ep\u003c/em\u003e\u0026lt;.001). In total, 17.0% of the autistic group had deliberately self-harmed recently, compared to 3.6% of the non-autistic group. The autistic group were five times more likely than the non-autistic comparison group to have deliberately self-harmed in the last year.\u0026nbsp;However, when accounting for the influence of current symptoms of depression, autism group was no longer a significant predictor of recent self-harm\u0026nbsp;(R\u003csup\u003e2\u003c/sup\u003e=.112, F=24.88, \u003cem\u003e\u003cu\u003ep\u003c/u\u003e\u003c/em\u003e\u003cu\u003e\u0026lt;.001; depression \u003cem\u003eb\u003c/em\u003e=.32, autism group \u003cem\u003eb\u003c/em\u003e=.03)\u003c/u\u003e. See Table 2.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eMethods of Deliberate Self-Harm\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAmong those who had deliberately self-harmed, no statistically significant differences were found, with comparable rates of self-harming methods being reported by the autistic and non-autistic groups. See Table 3 for frequencies of self-harming behaviours between groups.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTABLE 3 (HARM TYPES) ABOUT HERE\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eSuicidal Self-Harm\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe autistic group self-reported significantly higher rates of suicidal self-harm in comparison to the non-autistic group (\u0026chi;\u003csup\u003e2\u003c/sup\u003e=22.84, \u003cem\u003ep\u003c/em\u003e\u0026lt;.001). In total, 20.2% of the autistic group had engaged in suicidal self-harm, in comparison to 3.6% of the non-autistic group. The autistic group were nearly seven times more likely to engage in suicidal self-harm than the non-autistic group. The pattern of results remained when accounting for the influence of current depression symptoms (R\u003csup\u003e2\u003c/sup\u003e=.101, F=21.99, \u003cem\u003e\u003cu\u003ep\u003c/u\u003e\u003c/em\u003e\u003cu\u003e\u0026lt;.001; depression \u003cem\u003eb\u003c/em\u003e=.23, autism group \u003cem\u003eb\u003c/em\u003e=.12)\u003c/u\u003e. See Table 2.\u003c/p\u003e\n\u003cp\u003eWhen examining the overlap between suicidal ideation and suicidal self-harm, 26% of autistic individuals who had experienced suicidal ideation also engaged in suicidal self-harm, in comparison to 14% of non-autistic individuals. This difference was significant (\u0026chi;\u003csup\u003e2\u003c/sup\u003e=43.42, \u003cem\u003ep\u003c/em\u003e\u0026lt;.001) with a medium effect size (Cramer\u0026rsquo;s \u003cem\u003ev=\u003c/em\u003e.34).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eGender Differences in Self-harm and Suicidality\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWhen comparing the experience of autistic women to autistic men, our analyses indicated that autistic women self-reported significantly higher rates of suicidal ideation (women: 77.4% vs. men: 67.0%, respectively;\u0026nbsp;\u0026chi;\u003csup\u003e2\u003c/sup\u003e=9.78, \u003cem\u003ep\u003c/em\u003e=.008), thoughts of self-harm (74.2% vs. 56.4%;\u0026nbsp;\u0026chi;\u003csup\u003e2\u003c/sup\u003e=9.64, \u003cem\u003ep\u003c/em\u003e=.008), deliberate self-harm (62.1% vs. 44.7%;\u0026nbsp;\u0026chi;\u003csup\u003e2\u003c/sup\u003e=6.54, \u003cem\u003ep\u003c/em\u003e=.011)\u0026nbsp;and suicidal self-harm (26.6% vs. 11.7%;\u0026nbsp;\u0026chi;\u003csup\u003e2\u003c/sup\u003e=7.38, \u003cem\u003ep\u003c/em\u003e=.007) when compared to autistic men; however, no statistical differences were found between autistic women and autistic men in recent thoughts of self-harm or recent deliberate self-harm. When considering the frequency of these experiences, autistic women were found to have more frequent thoughts of suicidal ideation (8.9% once, 68.5% more than once) when compared to autistic men (18.6% once, 48.4% more than once), as well as more frequent of thoughts of harm (autistic women: 12.1% once, 61.1% more than once; vs. autistic men:14.9% once, 41.5% more than once), but not in the frequency of deliberate harm. Few gender differences were found in the non-autistic group, with only rates of suicidal ideation reaching statistical significance (non-autistic women: 32.9% vs. non-autistic men: 19.0%;\u0026nbsp;\u0026chi;\u003csup\u003e2\u003c/sup\u003e=8.80, \u003cem\u003ep=\u003c/em\u003e.012). The patterns of results remained when accounting for the influence of current depression symptoms. See Supplementary Table 1.\u003c/p\u003e\n\u003cp\u003eFor methods of self-harming behaviours, no statistical differences were found between autistic women and autistic men, with similar rates of each method of harm being used. This sub-group analysis was not conducted in the non-autistic group due to low endorsement of suicide experiences resulting in low statistical power. See Supplementary Table 2.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAge Differences in Self-harm and Suicidality in the Autistic group\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWhen comparing the experience of autistic people in midlife (ML; i.e., aged 40-64 years) and old age (OA; i.e., aged 65+ years), our analyses indicated that autistic people in old age self-reported significantly higher rates of self-harming thoughts (OA: 76.1% vs. ML: 60.0%; \u0026chi;\u003csup\u003e2\u003c/sup\u003e=6.20, \u003cem\u003ep\u003c/em\u003e=.043), deliberate self-harm (OA: 70.5% vs. ML: 43.8%; \u0026chi;\u003csup\u003e2\u003c/sup\u003e=14.98, \u003cem\u003ep\u003c/em\u003e\u0026lt;.001), recent deliberate self-harm (OA: 23.9% vs. ML: 12.3%), and suicidal self-harm (OA: 28.4% vs. ML: 14.6%; \u0026chi;\u003csup\u003e2\u003c/sup\u003e=4.97, \u003cem\u003ep\u003c/em\u003e=.026) when compared to autistic people in midlife; however, no statistical differences were found between autistic people in midlife and old age in suicidal ideation (ML: 68.7% vs. OA: 79.5%). %). When considering the frequency of these experiences, autistic people in old age were found to have more frequent thoughts of thoughts of harm (OA: 60.2% more than once, vs. ML: 48.5% more than once), but not in the frequency of suicidal ideation or deliberate harm. The patterns of results in thoughts of harm, deliberate self-harm and suicidal self-harm remained when accounting for the influence of current depression symptoms, however, age group as a predictor of recent thoughts of harm and recent deliberate self-harm were no longer statistically significant after controlling for depression. See Supplementary Table 3.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;For methods of self-harming behaviours, autistic people in midlife were statistically more likely to self-injure through cutting, scratching or hitting compared to the autistic people in midlife (ML: 75.4% vs. OA 49.2%; \u0026chi;\u003csup\u003e2\u003c/sup\u003e=8.71, \u003cem\u003ep\u003c/em\u003e=.003), while the autistic people in old were more likely to self-injure by ingesting medications more than the norma dosage (OA: 59.7% vs. ML: 38.6%; \u0026chi;2=5.28, \u003cem\u003ep\u003c/em\u003e=.0.22) or by swallowing dangerous objects or products (OA: 30.6% vs. ML: 14.0%; \u0026chi;\u003csup\u003e2\u003c/sup\u003e=4.67, \u003cem\u003ep\u003c/em\u003e=.031). No other statistical differences were found. See Supplementary Table 4.\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eUsing data from a sample of people in midlife and older age, this study provides evidence that middle-aged and older autistic adults self-report higher rates and frequencies of self-harm and suicidality than age- and sex-matched non-autistic comparisons, including when accounting for current symptoms of depression. Some gender differences were observed, with autistic women reporting higher rates and frequencies of suicidal ideation and higher rates of suicidal self-harm than autistic men. Additionally, autistic adults in older age had higher rates of deliberate self-harm, including suicidal self-harm, than autistic adults in midlife. These findings \u0026ndash; which broadly replicate and extend Stewart et al.\u0026rsquo;s (\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; 31) results from a high autistic trait (not diagnosed) sample \u0026ndash; contributes valuable information about suicidality in autistic people in midlife and older age, a demographic that has historically been overlooked.\u003c/p\u003e \u003cp\u003eThe first key finding in the current study was that the autistic participants in midlife and older age self-reported significantly higher rates of suicidal ideation and self-harming thoughts than non-autistic comparisons The autistic group were also significantly more likely to have a higher frequency of these problems, with 60% having experienced suicidal ideation more than once. Our findings align with previous research, such as a UK-based clinical cohort study by Cassidy et al., (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2014\u003c/span\u003e; 16), which reported that 66% (n\u0026thinsp;=\u0026thinsp;243) of autistic adults had contemplated suicide. Additionally, comparable rates were also found in Stewart et al., (\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; 31), which found that 73% of middle-aged and older adults with high autistic traits had experienced suicidal ideation. While suicidal ideation and thoughts of self-harm were not uncommon in the non-autistic group, the autistic group were six to eight times more likely to have had these experiences, highlighting that suicidality is a pressing health issue in autistic populations.\u003c/p\u003e \u003cp\u003eWhen considering why rates and frequencies of suicidal ideation may be so high in autistic populations, mental health challenges likely play a key role. Autistic individuals show higher prevalence rates for nearly all mental health conditions compared to non-autistic counterparts (8\u0026ndash;9, 42). Mental health problems are also of concern in the current study, with the autistic group being found to report significantly higher depression symptom scores than the non-autistic group. There is a growing body of research as to why autistic people often have more mental health problems than the general population (e.g., social isolation, social stigma, victimisation and trauma, rigid cognitive style, and poorer normative outcomes; 27, 43), which in turn may exacerbate feelings of hopelessness, which is a core feature of suicidal ideation and may lead to periods of suicidal crisis (18, 21, 44). This interaction between autism, biopsychosocial risk factors, and suicidal ideation suggests a complex interplay of factors. While our current study did account for depression in our analyses (with the pattern of results remaining unchanged) further investigation of the influence of depression and other risk factors is needed.\u003c/p\u003e \u003cp\u003eAnother key finding of this study was the significantly higher rates of deliberate self-harm reported by the autistic group, where over half of the autistic participants had engaged in self-harm. Of those who had harmed, approximately three-quarters of the autistic group had deliberately self-harmed three or more times. This finding is consistent with previous research showing that a significant proportion of autistic individuals (50\u0026ndash;65%) engage in deliberate self-harm (18, 19, 21). However, this rate of harm is notably higher than the 20% rate reported by Stewart et al. (\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2023\u003c/span\u003e); this difference could be attributed to study design differences (i.e., convenience sampling vs. large-scale longitudinal study of healthy ageing), sampling differences (e.g., diagnosed/self-identified autistic people vs. those with high autistic traits), and that some self-harming behaviours (e.g., hitting, scratching) may be stimming behaviours that autistic people engage in for therapeutic reasons (45).\u003c/p\u003e \u003cp\u003eWhen considering the high rates reported in the current study and other studies involving autistic people with a diagnosis, several factors may play an important role in why autistic people self-harm. For some autistic individuals, self-harm may serve as a coping mechanism to regulate sensory overload or express unmet emotional needs (46). Late autism diagnoses may also contribute to higher rates of self-harm, as individuals with a late diagnosis may experience greater social difficulties, mental health issues, and frustration due to the delayed recognition of their condition (47\u0026ndash;50). This may lead to feelings of perceived burdensomeness and thwarted belongingness, which are central to the Interpersonal Theory of Suicide (36). The interplay between these factors may help explain the heightened rates of suicidal ideation and behaviour observed in the autistic population.\u003c/p\u003e \u003cp\u003eThe third key finding showed that middle-aged and older autistic adults also self-reported higher rates of suicidal self-harm than non-autistic adults. The rates of these experiences in the current study are higher than those documented in previous research (17% of autistic and 4% of non-autistic participants), for example, Hirvikoski et al. (\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2020\u003c/span\u003e; 22) and Stewart et al. (\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; 31) report that 8\u0026ndash;13% of autistic / high autistic trait adults experience suicidal self-harm. This discrepancy may be influenced by the focus on middle-aged and older adults (i.e., lifetime experiences are likely to increase with age) or reflect the current study's sample size (although well powered), convenience sampling approach (although predominately recruited through large and well-established autism research networks), or potential self-report biases (51).\u003c/p\u003e \u003cp\u003eWhen thinking more broadly about why people may harm themselves with the intention of suicide, many factors may play an important role, which may be particularly impactful for autistic people (52\u0026ndash;53). In the general population, adults in relationships and in employment have lower suicide rates (54), including autistic adults (18, 44); these lower rates are likely due to increased social connectedness and support. Furthermore, autistic adults with unmet social support needs also have lower suicide rates (18). While suicidal ideation does not always lead to suicidal behaviour, the significantly higher rates of co-occurring ideation and self-harm in autistic adults highlights the need for interventions that have been specifically designed to support autistic people, for example tailored mental health support, ensuring autistic people have opportunities for support employment, as well as social opportunities to develop relationships with others.\u003c/p\u003e \u003cp\u003eOur gender-based analyses also yielded important information when considering the experiences of suicidality in autistic populations. The autistic women in midlife and older age in our current study reported almost three times higher rates of self-harm and suicidality than the autistic men. This pattern of results mirrors that in the general population. When considering why autistic women may have such high rates of suicidality compared to autistic men, increased masking/camouflaging, later diagnosis, co-occurring mental health conditions, and societal pressures may disproportionately affect autistic women (55). These factors may contribute to the feelings of thwarted belongingness and perceived burdensomeness that are central to suicidality according to the interpersonal theory of suicide, which has been applied to the general and autistic populations (36, 56\u0026ndash;58). Previous research has consistently found similar gender disparities to our study, with autistic women at higher risk for suicidal thoughts and behaviours compared to autistic men (18, 26). Taken together, these gender differences highlight the importance of adopting gender-sensitive approaches in both clinical practice and research.\u003c/p\u003e \u003cp\u003eFinally, our age-related analyses also provided important insight into potential vulnerabilities of autistic adults in older age (i.e., over 65 years old). Older autistic adults were found to report higher rates of self-harming thoughts, deliberate self-harm, and suicidal self-harm when compared to autistic adults in midlife (i.e., 40\u0026ndash;64 years old). While our questions often captured lifetime experiences (which likely increase with age), higher rates of recent self-harm were also found to be reported by the older autistic participants. These findings suggest that age-specific factors contribute to heightened self-harm risks in older populations, potentially due to increased social isolation (35, 50) and barriers to adequate healthcare support (59), warranting age-tailored interventions. Furthermore, the middle-aged autistic adults were more likely to self-injure through cutting, scratching, or hitting, while the older autistic adults were more likely to ingest medication overdoses or other dangerous objects/products indicating variations in self-harm methods across age groups. This highlights the importance of understanding age-related differences in clinical settings to better support autistic individuals throughout their lifespan.\u003c/p\u003e \u003cp\u003eThe findings of the current study have significant clinical implications. While suicidality cannot be directly 'treated', interventions can address underlying risk factors. There is a clear need for tailored screening tools, gender-sensitive approaches, and age-appropriate interventions for autistic adults. Promoting social connection, mitigating perceived burdensomeness, and reducing stigma should be key components of suicide prevention strategies. Implementation of the 2009 Autism Act (60) and enhanced professional training for adult service providers remains crucial. Training is essential to equip providers to support the complex needs of the often-underserved older autistic population (61). Future research priorities should include longitudinal studies to track changes in suicidality over time and development of comprehensive assessment tools (62). Additionally, future studies should examine the experiences of autistic people from gender minorities (e.g., trans and non-binary people), a group also known to be vulnerable to suicidality (63\u0026ndash;64). Finally, autistic people must be consulted when studying suicidality, to ensure the studies are conducted in a way sensitive to their experiences and to not cause unforeseen harm.\u003c/p\u003e \u003cdiv id=\"Sec17\" class=\"Section2\"\u003e \u003ch2\u003eStrengths and Limitations\u003c/h2\u003e \u003cp\u003eWhen contextualising the findings of the current study, several strengths and limitations are worth considering. For strengths, this study conducted extensive PPI interviews and project steering, which ensured topic relevance and accessibility. The breadth of survey topics likely reduced recruitment bias toward those with experiences of suicidality, increasing the generalisability of our findings. Additionally, diverse recruitment methods (e.g., online adverts, notices shared through large and well-established autism research networks, community centre notices) enhanced sample representativeness and includes older people who are potentially not actively using the internet and social media. Our sample was also well matched on key demographic factors, with almost half of the participants being men and the sample including those in later life (i.e., over the age of 80).\u003c/p\u003e \u003cp\u003eHowever, limitations must be acknowledged. The AgeWellAutism study was conducted online, and there has been a well-documented increase in the number of threats to data integrity due to spam and imposter participants (65). However, many of these issues arose after the COVID-19 pandemic, and the current study was conducted in Spring 2019. Another consideration is that this study relies on self-report, which may limit clinical accuracy and may not fully capture autistic experiences, particularly for individuals with language difficulties or intellectual disabilities. Furthermore, the cross-sectional study design does not allow for causal inferences to be made (66). And finally, potential survivor bias may skew data by predominantly representing healthier older adults and excluding critical insights from individuals who died by suicide that can only be gained through mortality reports (67\u0026ndash;68). While these limitations may restrict the overall generalisability of the findings, the results offer valuable insights into self-reported self-harm and suicidality experiences of autistic adults in midlife and older age. This study represents a critical step towards an enhanced understanding of suicidality in ageing autistic populations and highlights the need for tailored support to mitigate the risk of suicide in this population.\u003c/p\u003e \u003c/div\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eThis study provides important clinical insights regarding patterns in suicidality and suicidal behaviours in middle-aged and older autistic adults. First, middle-aged and older autistic adults demonstrate significantly higher rates of self-harm and suicidal behaviours compared to non-autistic peers. Second, notable gender differences exist, with autistic women showing heightened risk across all suicidality and suicidal self-harm items, highlighting the need for gender-sensitive approaches in assessment and intervention. Third, our findings emphasise the persistence and exacerbation of suicide risk into middle and older age, with older autistic adults reporting higher rates of lifetime and recent suicidality and suicidal self-harm behaviours, underlining the need for life-course approaches to suicide prevention. Taken as a whole, our findings represent a significant contribution to our understanding the rates of suicidality in autistic adults. Moving forward, it is crucial to consider gender and age-related differences in suicidality research, and to also consider potential mechanisms underpinning suicidality in autistic populations. By doing this, clinicians will be better equipped to support autistic people, including those in midlife and older age.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eRAADS-14: Ritvo Autism and Aspergers Diagnostic Scale, a measure of autistic traits\u003c/p\u003e\n\u003cp\u003ePHQ-8/9: Patient Health Questionnaire, a measure of depression\u003c/p\u003e\n\u003cp\u003eANOVA: Analysis of Variance, statistical test to analyse difference between means of two or more groups\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003e\u003cu\u003eETHICAL APPROVAL\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFull ethical approval was granted by the PNM Research Ethics Subcommittee at King's College London (HR-18/19–10941). Written, online informed consent was obtained from all participants, and research was conducted in accordance with the Declaration of Helsinki.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eCONSENT FOR PUBLICATION\u0026nbsp;\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eParticipants provided written informed consent for the publication of anonymised data as part of the consent process when agreeing to take part in the online study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eAVAILABILITY OF DATA AND MATERIALS\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe data that support the findings of this study are held by Dr. Gavin Stewart, but the availability of these data is restricted. The data were used under license for the current study and are not publicly available. However, the data may be available from the authors upon reasonable request and with permission from Dr. Gavin Stewart.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eCOMPETING INTERESTS\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNone to declare.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eACKNOWLEDGEMENTS\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors are grateful to the 12 autistic people who offered suggestions on content and provided feedback on the language-use and accessibility of the study materials.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eFUNDING\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAt the time of data collection, GRS was funded by an UKRI/ESRC LISS-DTP PhD studentship (ES/P000703/1). GRS is currently funded by a British Academy Postdoctoral Research Fellowship (PFSS23\\230043). FH is part-funded by the NIHR Maudsley Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King’s College London. The funders have had no role in the data collection, analysis, interpretation, or any other aspect pertinent to the study. The authors have not been paid to write this article by any agency. This paper represents independent research conducted by the authors, and the views expressed are those of the author(s) and not necessarily those of the BA, NIHR, NHS or KCL.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eAUTHOR’S CONTRIBUTIONS\u0026nbsp;\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAuthors FH, RAC and GRS conceived the AgeWellAutism study. GRS designed the online survey and selected materials. GRS conceived the current study. SR and GRS conducted analyses. SR wrote the manuscript under the supervision of GRS. FH and RAC reviewed the final draft. All authors have read and approved the final manuscript.\u0026nbsp;\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eOffice for National Statistics: Suicides in England and Wales: 2023 registrations. https://www.ons.gov.uk/peoplepopulationandcommunity/birthsdeathsandmarriages/deaths/bulletins/suicidesintheunitedkingdom/2023 (2024). Accessed 29 Aug 2024.\u003c/li\u003e\n\u003cli\u003eOffice for National Statistics: Suicides in the United Kingdom: 2019 registrations. https://www.ons.gov.uk/peoplepopulationandcommunity/birthsdeathsandmarriages/deaths/bulletins/suicidesintheunitedkingdom/2019registrations#suicide-methods (2020). Accessed 29 August 2024.\u003c/li\u003e\n\u003cli\u003eConwell Y, Duberstein PR, Caine ED. Suicide in older adults. Psychiatr Clin North Am. 2011;34(2):451-68. https://doi.org/10.1016/j.psc.2011.02.002\u003c/li\u003e\n\u003cli\u003eZeidan J, Fombonne E, Scorah J, et al. Global prevalence of autism: A systematic review update. 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Trends Psychiatry Psychother. 2020;42(3):276-281. https://doi.org/10.1590/2237-6089-2019-0092\u003c/li\u003e\n\u003cli\u003eErlangsen A, Jacobsen AL, Ranning A, Delamare AL, Nordentoft M, Frisch M. Transgender Identity and Suicide Attempts and Mortality in Denmark. JAMA. 2023;329(24):2145-2153. https://doi.org/10.1001/jama.2023.8627\u003c/li\u003e\n\u003cli\u003eMournet AM, Kellerman JK, Garner RC, Kleiman EM. Suicidal Thoughts and Behaviors Among Autistic Transgender or Gender-Nonconforming US College Students. JAMA Netw Open. 2024;7(10):e2438345. https://doi.org/10.1001/jamanetworkopen.2024.38345\u003c/li\u003e\n\u003cli\u003ePellicano E, Adams D, Crane L, et al. Letter to the Editor: A possible threat to data integrity for online qualitative autism research. Autism. 2024;28(3):786-792. https://doi.org/10.1177/13623613231174543\u003c/li\u003e\n\u003cli\u003eWang X, Cheng Z. Cross-Sectional Studies: Strengths, Weaknesses, and Recommendations. Chest. 2020;158(1S):S65-S71. https://doi.org/10.1016/j.chest.2020.03.012\u003c/li\u003e\n\u003cli\u003eGolomb BA, Chan VT, Evans MA, Koperski S, White HL, Criqui MH. The older the better: are elderly study participants more non-representative? A cross-sectional analysis of clinical trial and observational study samples. BMJ Open. 2012;2(6):e000833. https://doi.org/10.1136/bmjopen-2012-000833\u003c/li\u003e\n\u003cli\u003eSegerstrom SC, Combs HL, Winning A, Boehm JK, Kubzansky LD. The happy survivor? Effects of differential mortality on life satisfaction in older age. Psychol Aging. 2016;31(4):340-345. https://doi.org/10.1037/pag0000091.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" style=\"width: 601px;\"\u003e\n \u003cp\u003e\u003cem\u003eTable 1. Demographic characteristics of autistic and non-autistic groups.\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eAutistic\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(n=222)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eNon-Autistic\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(n=166)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eGroup Difference\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eEffect Size\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eAge (years)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eM (SD)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e60.89 (12.84)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e60.55 (13.58)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\"\u003e\n \u003cp\u003e\u003cem\u003et(386)\u003c/em\u003e=.247\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep=\u003c/em\u003e.805\u003csup\u003en/s\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\"\u003e\n \u003cp\u003e\u003cem\u003ed\u003c/em\u003e=0.03\u003c/p\u003e\n \u003cp\u003e[-0.23, 0.18]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e[95% CI]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e[59.18, 62.59]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e[58.47, 62.64]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eRange\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e40-91\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e40-93\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eGender\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eN men : women\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e98 : 124\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e84 : 82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=1.59,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e=.207\u003csup\u003en/s\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\"\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.06\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e44.1% : 55.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e50.6% : 49.4%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eLiving Situation\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eSpouse or partner\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e85 (38.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e79 (47.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=3.37,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep=\u003c/em\u003e.066\u003csup\u003en/s\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.09\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eChildren\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e62 (27.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e39 (23.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=0.97,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e=.325\u003csup\u003en/s\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eSibling\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e24 (10.8%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0 \u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=19.13,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u0026lt;.001***\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.22\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eParent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e19 (8.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e7 (4.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=2.86,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e=.09\u003csup\u003en/s\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.09\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eOther family member\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e7 (3.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0 \u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=5.33,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e=.021*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eRoommate/friend\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e20 (9.0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e12 (7.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=0.40,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep=\u003c/em\u003e.528\u003csup\u003en/s\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.03\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eSupported Housing\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e38 (17.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e20 (12.0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=1.92,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e=.166\u003csup\u003en/s\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.07\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eAlone/Independently\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e41 (18.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e57 (34.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=12.67,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u0026lt;\u003c/em\u003e.001***\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.18\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eEducation Level\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eNo formal qualifications\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e23 (10.4%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4 (2.4%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"5\"\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=16.97\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e=.002**\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"5\"\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.21\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eSchool to 16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e50 (22.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e27 (16.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eSchool to 18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e61 (27.5%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e65 (39.2%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eUndergraduate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e54 (24.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e51 (30.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003ePostgraduate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e34 (15.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e19 (11.4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" style=\"width: 601px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEmployment Status\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eEmployed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e69 (31.1%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e87 (52.4%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"4\"\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=35.04\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u0026lt;.001***\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"4\"\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.30\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eUnemployed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e24 (10.8%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3 (1.8%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eUnable to work due\u003c/p\u003e\n \u003cp\u003eto health\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e24 (10.8%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2 (1.2%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eRetired\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e105 (47.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e74 (44.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" style=\"width: 601px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAutism Diagnosis/Identification\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eDiagnosed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e211 (95.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cul\u003e\n \u003cli\u003e\u0026nbsp;\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cul\u003e\n \u003cli\u003e\u0026nbsp;\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eSelf-Identified\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e11 (4.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cul\u003e\n \u003cli\u003e\u0026nbsp;\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" style=\"width: 601px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eYears since Autism Diagnosis/Identity\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eM (SD)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e9.42 (7.66)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cul\u003e\n \u003cli\u003e\u0026nbsp;\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eRange (years)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0-43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eAutism Traits\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e(max score=42)\u003c/p\u003e\n \u003cp\u003eM (SD)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e32.74 (7.53)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.95 (4.07)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003et\u003c/em\u003e(386)=49.96,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u0026lt;.001***\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003ed\u003c/em\u003e=4.74\u003c/p\u003e\n \u003cp\u003e[4.07, 7.53]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" style=\"width: 601px;\"\u003e\n \u003cp\u003e\u003cem\u003eNote.\u003c/em\u003e N=388. \u003cem\u003ed\u003c/em\u003e=Cohen\u0026rsquo;s \u003cem\u003ed. v\u003c/em\u003e=Cramer\u0026rsquo;s \u003cem\u003ev.\u0026nbsp;\u003c/em\u003e*\u003cem\u003ep\u003c/em\u003e \u0026lt;.05, **\u003cem\u003ep\u003c/em\u003e \u0026lt;.01. ***\u003cem\u003ep\u003c/em\u003e \u0026lt;.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003e\n \u003cp\u003e\u003cem\u003eTable 2. Self-reported prevalence rates of self-harm and suicidality in the Autistic and Non-Autistic groups.\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 236px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 120px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAutistic\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(n=222)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNon-Autistic\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(n=166)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 132px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGroup Difference\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEffect Size\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 145px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eOdds Ratio\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003e\n \u003cp\u003e\u003cstrong\u003eSuicidal Ideation - Many people have felt that life is not worth living. Have you felt that way?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 236px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 120px;\"\u003e\n \u003cp\u003e59 (26.9%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e123 (74.1%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 132px;\"\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=129.84,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u0026lt;.001***\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 112px;\"\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.58\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 145px;\"\u003e\n \u003cp\u003e7.85\u003c/p\u003e\n \u003cp\u003e[4.97, 12.41]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 236px;\"\u003e\n \u003cp\u003eYes, once\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 120px;\"\u003e\n \u003cp\u003e29 (13.2%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e36 (21.7%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 236px;\"\u003e\n \u003cp\u003eYes, more than once\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 120px;\"\u003e\n \u003cp\u003e131 (59.8%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e7 (4.2%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003e\n \u003cp\u003e\u003cstrong\u003eThoughts of Harm - Have you contemplated harming yourself (for example by cutting, biting, hitting yourself or taking an overdose)?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 236px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 120px;\"\u003e\n \u003cp\u003e73 (33.5%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e124 (74.7%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 132px;\"\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=85.67,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u0026lt;.001***\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 112px;\"\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 145px;\"\u003e\n \u003cp\u003e5.90\u003c/p\u003e\n \u003cp\u003e[3.77, 9.25]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 236px;\"\u003e\n \u003cp\u003eYes, once\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 120px;\"\u003e\n \u003cp\u003e29 (13.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e27 (16.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 236px;\"\u003e\n \u003cp\u003eYes, more than once\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 120px;\"\u003e\n \u003cp\u003e116 (53.2%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e15 (9.0%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003e\n \u003cp\u003e\u003cstrong\u003eThoughts of Harm (Recent) - Have you contemplated harming yourself in the last 12 months?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 236px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 120px;\"\u003e\n \u003cp\u003e123 (56.4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e157 (94.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 132px;\"\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=69.48,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u0026lt;.001***\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 112px;\"\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 145px;\"\u003e\n \u003cp\u003e13.47\u003c/p\u003e\n \u003cp\u003e[6.54, 27.77]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 236px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 120px;\"\u003e\n \u003cp\u003e95 (43.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e9 (5.4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003e\n \u003cp\u003e\u003cstrong\u003eDeliberate Harm - Have you deliberately harmed yourself, whether or not you meant to end your life?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 236px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 120px;\"\u003e\n \u003cp\u003e99 (45.0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e144 (86.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 132px;\"\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=69.29,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u0026lt;.001***\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 112px;\"\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 145px;\"\u003e\n \u003cp\u003e7.86\u003c/p\u003e\n \u003cp\u003e[4.67, 13.26]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 236px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 120px;\"\u003e\n \u003cp\u003e121 (55.0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e22 (13.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003e\n \u003cp\u003e\u003cstrong\u003eFrequency of Harm \u0026ndash; If yes, how many times have you harmed yourself?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 236px;\"\u003e\n \u003cp\u003eOnce\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 120px;\"\u003e\n \u003cp\u003e18 (14.9%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e13 (54.2%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 132px;\"\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=22.62,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u0026lt;.001***\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 112px;\"\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 145px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 236px;\"\u003e\n \u003cp\u003eTwice\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 120px;\"\u003e\n \u003cp\u003e13 (10.7%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e6 (25.0%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 236px;\"\u003e\n \u003cp\u003eThree or more times\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 120px;\"\u003e\n \u003cp\u003e90 (74.4%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e5 (20.8%)\u003csup\u003eǂ\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003e\n \u003cp\u003e\u003cstrong\u003eDeliberate Harm (Recent) - Have you harmed yourself in the last 12 months, whether or not you meant to end your life?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 236px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 120px;\"\u003e\n \u003cp\u003e181 (83.0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e160 (96.4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 132px;\"\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=16.91,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u0026lt;.001***\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 112px;\"\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 145px;\"\u003e\n \u003cp\u003e5.41\u003c/p\u003e\n \u003cp\u003e[2.24, 13.25]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 236px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 120px;\"\u003e\n \u003cp\u003e37 (17.0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e6 (3.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003e\n \u003cp\u003e\u003cstrong\u003eSuicidal Harm - Have you deliberately taken an overdose or harmed yourself with the intention to end your life?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 236px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 120px;\"\u003e\n \u003cp\u003e174 (79.8%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e160 (96.4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 132px;\"\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=22.84,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u0026lt;.001***\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 112px;\"\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 145px;\"\u003e\n \u003cp\u003e6.74\u003c/p\u003e\n \u003cp\u003e[2.80, 16.25]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 236px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 120px;\"\u003e\n \u003cp\u003e44 (20.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e6 (3.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003e\n \u003cp\u003e\u003cem\u003eNote.\u0026nbsp;\u003c/em\u003e\u003csup\u003eǂ\u0026nbsp;\u003c/sup\u003eAdjusted residual indicates proportional difference. Odds ratios calculated with yes/frequency options grouped. *\u003cem\u003ep\u003c/em\u003e \u0026lt;.05, **\u003cem\u003ep\u003c/em\u003e \u0026lt;.01. ***\u003cem\u003ep\u003c/em\u003e \u0026lt;.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eTable 3. Self-reported types of harm used by those who have self-harmed.\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eAutistic\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(n=116)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eNon-Autistic\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(n=22)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eGroup Difference\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eEffect Size\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\"\u003e\n \u003cp\u003e\u003cstrong\u003eTypes of Harm \u0026ndash; Have you done any of the following to harm or endanger yourself?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eStopping prescribed medication\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e21 (18.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3 (13.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=0.28,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e=.612\u003csup\u003en/s\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.04\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eSwallowing dangerous objects or products\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e27 (22.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1 (4.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=3.84\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e=.050\u003csup\u003en/s\u003c/sup\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.17\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eIngesting alcohol or recreational/illicit drug\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e28 (23.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3 (13.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=1.10,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e=.295\u003csup\u003en/s\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.09\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eIngesting a medication more than the normal dosage\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e59 (49.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e11 (50.0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=0.01,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e=.971\u003csup\u003en/s\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e\u0026lt;.01\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eSelf-injury (e.g., cutting, scratching, hitting)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e74 (61.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e10 (45.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e=2.02,\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e=.155\u003csup\u003en/s\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003ev\u003c/em\u003e=.12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eNote. Participants could select multiple options, thus total does not equal 100%.\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"molecular-autism","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"mola","sideBox":"Learn more about [Molecular Autism](http://molecularautism.biomedcentral.com/)","snPcode":"13229","submissionUrl":"https://submission.nature.com/new-submission/13229/3","title":"Molecular Autism","twitterHandle":"@MolecularAutism","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Autism, Self-Harm, Suicidality, Midlife, Older age","lastPublishedDoi":"10.21203/rs.3.rs-6511234/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6511234/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eSuicide has been reported as a leading cause of premature death in autistic populations. Additionally, risk of suicidality is often found to increase with age in the general population. Despite this, suicidality has seldom been explored in autistic populations in midlife and older age. This study investigates the self-reported prevalence of self-harm and suicidality in autistic people in midlife and older age compared to an age- and gender-matched non-autistic comparison group.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eIn total, 388 participants (autistic n\u0026thinsp;=\u0026thinsp;222, 44% men) aged 40\u0026ndash;93 years (mean\u0026thinsp;=\u0026thinsp;60.9 years) from the AgeWellAutism study completed questionnaires related to experiences of suicidal ideation, self-harming thoughts, deliberate self-harm, and suicidal self-harm. Group, gender and age differences were examined chi-square and linear regression analyses.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThe autistic group reported significantly higher rates of suicidal ideation, self-harming thoughts, deliberate self-harm, and suicidal self-harm than the non-autistic comparison group. When considering gender differences in the autistic group (but not the non-autistic group due to limited sample size), autistic women reported significantly higher rates of suicidal ideation and suicidal self-harm compared to autistic men; no other gender differences were found. When considering age differences, autistic people in old age were more likely to have had thoughts of self-harm, to have deliberately self-harmed, and to have experienced suicidal self-harm than autistic people in midlife.\u003c/p\u003e\u003ch2\u003eLimitations:\u003c/h2\u003e \u003cp\u003eThe AgeWellAutism study is a cross-sectional convenience sample that relies on self-report. Survivor bias may also influence findings, as the study design would exclude those who have died by suicide, potentially leading to an underestimation of suicidality.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eAutistic adults may be particularly susceptible to experiences of self-harm and suicidality in midlife and older age, particularly autistic women. Additionally, autistic people in old age were also more likely to experience suicidality (including recent experiences) than autistic people in midlife. These findings highlight the urgent need for targeted suicide prevention strategies and mental health interventions for autistic adults in midlife and older age, particularly autistic women and older people.\u003c/p\u003e","manuscriptTitle":"Self-Harm and Suicidality Experiences of Autistic and Non-Autistic Adults in Midlife and Older Age","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-05-04 17:17:32","doi":"10.21203/rs.3.rs-6511234/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-07-11T22:42:53+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-05-27T19:47:09+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"52867726864398521029789594153400980144","date":"2025-05-17T03:02:01+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-05-03T15:39:52+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"323246043392513031268724457211441781520","date":"2025-04-28T19:20:59+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"226919473295197255579617005633599783491","date":"2025-04-28T16:54:22+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-04-28T08:29:19+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-04-25T15:10:11+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-04-24T06:46:21+00:00","index":"","fulltext":""},{"type":"submitted","content":"Molecular Autism","date":"2025-04-23T09:35:08+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"molecular-autism","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"mola","sideBox":"Learn more about [Molecular Autism](http://molecularautism.biomedcentral.com/)","snPcode":"13229","submissionUrl":"https://submission.nature.com/new-submission/13229/3","title":"Molecular Autism","twitterHandle":"@MolecularAutism","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"718d4649-3fc9-4d83-bddd-adafda7abf4f","owner":[],"postedDate":"May 4th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-12-01T16:00:51+00:00","versionOfRecord":{"articleIdentity":"rs-6511234","link":"https://doi.org/10.1186/s13229-025-00693-x","journal":{"identity":"molecular-autism","isVorOnly":false,"title":"Molecular Autism"},"publishedOn":"2025-11-25 15:57:22","publishedOnDateReadable":"November 25th, 2025"},"versionCreatedAt":"2025-05-04 17:17:32","video":"","vorDoi":"10.1186/s13229-025-00693-x","vorDoiUrl":"https://doi.org/10.1186/s13229-025-00693-x","workflowStages":[]},"version":"v1","identity":"rs-6511234","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6511234","identity":"rs-6511234","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}