Sociodemographic and clinical risk factors for suicidal ideation and suicide attempt in functional/dissociative seizures and epilepsy: a large cohort study

ABSTRACT Objective To identify risk factors for first episodes of suicidal ideation and suicide attempt in people with functional/dissociative seizures (FDS) or epilepsy. Methods Retrospective cohort study from the UK’s largest tertiary mental health care provider, with linked national admission data from the Hospital Episode Statistics (HES). Participants were 2383 people with a primary or secondary diagnosis of FDS or epilepsy attending between 01/01/2007 and 18/06/2021. Outcomes were a first report of suicidal ideation and a first hospital admission for suicide attempt (ICD-10 X60-X84). Demographic and clinical risk factors were assessed using multivariable bias-reduced binomial-response generalised linear models. Results In both groups, ethnic minorities had significantly reduced odds of hospitalisations following a suicide attempt (OR: 0.45 – 0.49). Disorder-specific risk factors were gender, age, and comorbidity profile. In FDS, both genders had similar risk of suicidality; younger age was a risk factor for both outcomes (OR: 0.16 – 1.91) and a diagnosis of Depression or Personality Disorders was associated with higher odds of reporting suicidal ideation (OR: 1.91 and 3.01 respectively). In epilepsy, females had higher odds of being hospitalised following suicide attempt (OR: 1.64). Age had a quadratic association with both outcomes (OR: 0.88 – 1.06). A Substance Abuse Disorder was associated to higher suicidal ideation (OR: 2.67) whilst Developmental Disorders lowered the risk (OR: 0.16 – 0.24). Conclusions This is the first study systematically reporting risk factors for suicidality in people with FDS. Results for the large epilepsy cohort complement previous studies and will be useful in future meta-analyses. KEY MESSAGE BOX What is already known on this topic People with epilepsy and people with functional/dissociative seizures (FDS) are at elevated risk of suicide Identification of risk factors for suicidal ideation and suicide attempt in high-risk groups is essential to inform risk prevention strategies What this study adds Several factors are associated with suicidality in FDS, including age, ethnicity, comorbid Depression and Personality Disorders. In epilepsy, suicidality is associated with age, gender, ethnicity, comorbid Substance Misuse Disorder and Developmental Disorders. How this study might affect research, practice or policy Whilst disorder-specific factors will be useful to identify groups at higher risk in clinical settings, general risk factors can be target of population-based preventive strategies.