Association between Digestive Diseases, Nighttime Sleep, and Depressive Symptoms among the Middle-aged and Elderly Adults: A Mediation Analysis

Association between Digestive Diseases, Nighttime Sleep, and Depressive Symptoms among the Middle-aged and Elderly Adults: A Mediation Analysis | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Association between Digestive Diseases, Nighttime Sleep, and Depressive Symptoms among the Middle-aged and Elderly Adults: A Mediation Analysis Congcong Cheng, Dinghui Guo, Xu Cao, Dingmin Wang, Wenling Li, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5881924/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Backgrounds: As the population ages, the relationship among digestive diseases, nighttime sleep duration, and depressive symptoms in middle-aged and elderly adults, especially sleep's mediating role, remains unclear, thus prompting research. Aims To explore how nighttime sleep duration mediates between digestive diseases and depressive symptoms in this group, aiming to guide clinical treatment of related depression. Methods Using 2015–2020 China Health and Retirement Longitudinal Study (CHARLS) data, we applied difference, Spearman correlation, and multivariate logistic regression analyses. A mediating effect model was set up and tested via the Bootstrap method. Results Digestive diseases had a 23.05% prevalence rate, and depressive symptoms had a 35.90% detection rate. Both digestive diseases (OR = 1.55, 95% CI: 1.38–1.73) and insufficient nighttime sleep (OR = 2.17, 95% CI: 1.97–2.40) significantly affected depressive symptoms. The model showed that insufficient nighttime sleep had a partial mediating effect. Discussion Clinically, treating relevant patients requires a holistic approach with an emphasis on sleep. Future research should use objective measures and longitudinal studies to clarify mechanisms and causalities. Conclusion Digestive diseases can cause insufficient sleep, promoting depressive symptoms. Clinicians should not overlook sleep quality when treating digestive patients with comorbid depression, as improving sleep may relieve symptoms. Digestive diseases Depressive symptoms Nighttime sleep duration Mediating effect Middle-aged and elderly adults Figures Figure 1 1. Introduction With the acceleration of the population aging process and lifestyle change, the health issues of middle-aged and elderly adults have received extensive attention. On the one hand, due to the degeneration of physical functions, middle-aged and elderly adults often suffer from digestive diseases. Because of their multiplicity and recurrence, patients usually develop depressive emotions over time [ 1 ]. A study analyzed the global burden of digestive diseases from 1990 to 2019 [ 2 ]. The data showed that the prevalence rate of digestive diseases was 35% in 2019, accounting for a large part of the total disease burden. Among them, intestinal infections had the highest mortality rate, while chronic liver diseases had the highest prevalence rate. Digestive diseases are often accompanied by discomfort such as indigestion, abdominal pain, and abdominal distension, which seriously affect patients' quality of life and daily activity ability, bringing physical pain and psychological pressure to patients [ 3 ]. At this time, depression often follows. Studies have shown that the prevalence rate of depression in patients with inflammatory bowel disease is 25.2% [ 4 ]; in addition, among the patients in the gastroenterology department, the total detection rate of simple depressive symptoms is 31.11% [ 5 ]. Depression not only leads to psychological problems such as low mood, loss of interest, and sleep disorders but also weakens the body's immune function, increasing the risk of chronic diseases and the possibility of disease progression [ 6 ], thus forming a vicious cycle, that seriously affects the physical and mental health and quality of life of middle-aged and elderly adults. Previous studies [ 7 , 8 ] have shown that sleep quality plays a crucial role in the physiological and psychological regulation of the human body, especially for middle-aged and elderly adults. Nighttime sleep, as a key component of sleep, changes in its duration and quality are closely related to various health problems [ 9 , 10 ]. When middle-aged and elderly adults suffer from digestive diseases, they may frequently wake up due to physical discomfort such as nighttime abdominal pain, abdominal distension, and acid reflux, or have difficulty falling asleep due to worry and anxiety about the disease, thereby affecting nighttime sleep [ 11 ]. Sleep disorders may further interfere with the normal function of the neuroendocrine system, and affect the balance of neurotransmitters, thereby increasing the risk of depressive symptoms [ 12 ]. However, there are still deficiencies in the current research on the internal relationship among digestive diseases, nighttime sleep, and depressive symptoms in middle-aged and elderly adults. Most studies only focus on the simple association between the two, lacking in-depth exploration of the complex mechanism of action among the three [ 13 – 17 ]. In addition, the existing studies mostly focus on specific regions or small-scale populations in sample selection, lacking nationwide large sample data support with broad representativeness, making it difficult to comprehensively and accurately reflect the real situation of the middle-aged and elderly population in China. The China Health and Retirement Longitudinal Study (CHARLS) adopts stratified multi-stage probability sampling to recruit people aged 45 and above from nationally representative regions and widely collects personal and family information, providing an excellent data basis for studying aging issues [ 18 ]. Based on the CHARLS database, this study deeply analyzes the impact of digestive diseases on depressive symptoms in middle-aged and elderly adults, focuses on exploring the mediating effect and its magnitude of nighttime sleep duration, in order to provide more comprehensive clinical management for gastroenterology patients with comorbid depressive symptoms, contribute to the development of healthy aging, and improve the quality of life and happiness of middle-aged and elderly adults. 2. Methods 2.1 Data Source This study utilized the data of the China Health and Retirement Longitudinal Study (CHARLS) from 2015 to 2020. CHARLS is a large-scale population cohort study with the middle-aged and elderly in China as the research objects. It is representative of the middle-aged and elderly population in China. This survey has been approved by the Biomedical Ethics Committee of Peking University (IRB00001052-11015), and all survey subjects signed the informed consent form. In this study, the middle-aged and elderly aged ≥ 45 were selected as the research objects, and those with missing variable data such as digestive diseases, nighttime sleep duration, and depressive symptoms were deleted. A total of 8,610 research objects were included. 2.2 Research Variables 2.2.1 Definition of Digestive Diseases It mainly includes gastrointestinal diseases and liver diseases mentioned in the questionnaire. It was determined whether a person suffered from such diseases according to the two questions: "Have you been diagnosed by a doctor as having gastrointestinal diseases?" and "Have you been diagnosed by a doctor as having liver diseases?". If a person neither suffered from gastrointestinal diseases nor liver diseases, the digestive diseases were assigned a value of "0", otherwise, it was assigned a value of "1". 2.2.2 Measurement of Nighttime Sleep Duration It was obtained by extracting the question in the questionnaire: "In the past month, how many hours did the respondent enter and maintain the sleep state on average every night?". If the nighttime sleep duration was < 6 hours [ 19 , 20 ], it was regarded as insufficient nighttime sleep and assigned a value of "1", otherwise, it was assigned a value of "0". 2.2.3 Definition of Depressive Symptoms The 10 items in the Center for Epidemiologic Studies Depression Scale (CES-D10) [ 21 ] were used to detect depressive symptoms in the elderly. Each item in the scale contained 4 options, and each option was scored 0, 1, 2, and 3 points in turn. Questions 5 and 8 were reverse-scored because they were positive emotions. The total score ranged from 0 to 30 points. The higher the CES-D10 score, the more severe the depressive symptoms. In this study, the respondents with a cumulative CES-D10 score ≥ 10 points [ 22 , 23 ] were defined as having depressive symptoms and assigned a value of "1", otherwise, it was assigned a value of "0". 2.2.4 Selection of Covariates Demographic characteristics of the research objects, including gender, age, education level, place of residence, marital status, lifestyle habits such as smoking history, drinking history, social activity participation, body mass index (BMI), and the situation of chronic diseases, including hypertension, diabetes, cancer, chronic pulmonary diseases, heart diseases, mental diseases, arthritis, etc., were obtained from the questionnaire. 2.3 Statistical Analysis RStudio was used for data cleaning and statistical analysis. The research objects were divided into two groups according to the presence or absence of depressive symptoms, and their characteristics were described. Categorical variables were expressed as numbers (%). The chi-square test was used for inter-group difference analysis. Multivariate logistic regression analysis and Spearman correlation analysis were used to explore the relationships among digestive diseases, nighttime sleep, and depressive symptoms. The "mediation" package in RStudio was used to establish a mediation model to analyze the mediating effect of nighttime sleep between digestive diseases and depressive symptoms, and the bias-corrected percentile Bootstrap method was used for testing [ 24 ]. P < 0.05 was considered statistically significant. 3. Results 3.1 Basic Information of Research Objects As shown in Table 1 , a total of 8,610 middle-aged and elderly people were included as research objects in this study. Among them, 3,091 cases (35.90%) had depressive symptoms detected, and 5,519 cases (64.10%) did not; 2,685 cases (31.18%) had a nighttime sleep duration of < 6 hours, while 5,925 cases (68.82%) had a nighttime sleep duration of ≥ 6 hours; in terms of digestive diseases, 6,625 cases (76.95%) had no digestive diseases, 234 cases (2.72%) had only liver diseases, 1,564 cases (18.16%) had only gastrointestinal diseases, and 187 cases (2.17%) had both diseases. The prevalence rate of digestive diseases was 23.05%. Taking depressive symptoms as a categorical variable, the difference test was performed on the two groups of research objects. The results showed that the differences in variables such as age, gender, education level, marital status, place of residence, BMI, smoking history, drinking history, social activity participation, nighttime sleep duration, hypertension, diabetes, chronic pulmonary diseases, heart diseases, mental diseases, arthritis, and digestive diseases between the two groups of research objects were statistically significant (P < 0.05), while the difference in cancer between the two groups was not significant (P = 0.39). Compared with the non-depressive group, the middle-aged and elderly with depressive symptoms detected had shorter nighttime sleep and a higher prevalence rate of digestive diseases. Table 1 Basic information of research subjects and difference tests [n (%)] Variables Total (n = 8610) Non-depressive (n = 5519) Depressive (n = 3091) χ² Age group, n (%) 20.70 *** 70 1072 (12.45) 689 (12.48) 383 (12.39) sex, n (%) 230.21 *** Female 6500 (75.49) 3876 (70.23) 2624 (84.89) Male 2110 (24.51) 1643 (29.77) 467 (15.11) Educational level, n (%) 43.35 *** Illiterate 635 (7.38) 359 (6.50) 276 (8.93) Primary school- 899 (10.44) 537 (9.73) 362 (11.71) Middle school 380 (4.41) 284 (5.15) 96 (3.11) High school+ 6696 (77.77) 4339 (78.62) 2357 (76.25) Marital, n (%) 73.81 *** Married 7587 (88.12) 4987 (90.36) 2600 (84.12) Single 1023 (11.88) 532 (9.64) 491 (15.88) Residence, n (%) 116.49 *** Rural 6926 (80.44) 4249 (76.99) 2677 (86.61) Urban 1684 (19.56) 1270 (23.01) 414 (13.39) BMI (kg/m 2 ), n (%) 7.63 * 28 1334 (15.49) 877 (15.89) 457 (14.78) Smoking history, n (%) 55.18 *** No 7623 (88.54) 4781 (86.63) 2842 (91.94) Yes 987 (11.46) 738 (13.37) 249 (8.06) Drinking history, n (%) 45.51 *** No 7124 (82.74) 4453 (80.68) 2671 (86.41) Yes 1486 (17.26) 1066 (19.32) 420 (13.59) Social activities, n (%) 51.38 *** No 4809 (55.85) 3241 (58.72) 1568 (50.73) Yes 3801 (44.15) 2278 (41.28) 1523 (49.27) Nighttime sleep, n (%) 387.83 *** < 6 h 2685 (31.18) 1315 (23.83) 1370 (44.32) ≥ 6 h 5925 (68.82) 4204 (76.17) 1721 (55.68) Hypertension, n (%) 11.99 *** No 6448 (74.89) 4200 (76.10) 2248 (72.73) Yes 2162 (25.11) 1319 (23.90) 843 (27.27) Diabetes, n (%) 11.02 *** No 7992 (92.82) 5161 (93.51) 2831 (91.59) Yes 618 (7.18) 358 (6.49) 260 (8.41) Cancer, n (%) 0.39 No 8523 (98.99) 5466 (99.04) 3057 (98.90) Yes 87 (1.01) 53 (0.96) 34 (1.10) Chronic lung diseases, n (%) 105.35 *** No 7996 (92.87) 5243 (95.00) 2753 (89.07) Yes 614 (7.13) 276 (5.00) 338 (10.93) Heart diseases, n (%) 47.37 *** No 7538 (87.55) 4933 (89.38) 2605 (84.28) Yes 1072 (12.45) 586 (10.62) 486 (15.72) Mental diseases, n (%) 41.39 *** No 8536 (99.14) 5498 (99.62) 3038 (98.29) Yes 74 (0.86) 21 (0.38) 53 (1.71) Arthritis, n (%) 278.64 *** No 6132 (71.22) 4267 (77.31) 1865 (60.34) Yes 2478 (28.78) 1252 (22.69) 1226 (39.66) Digestive diseases, n (%) 209.54 *** None 6625 (76.95) 4518 (81.86) 2107 (68.17) Only liver diseases 234 (2.72) 128 (2.32) 106 (3.43) Only gastrointestinal diseases 1564 (18.16) 809 (14.66) 755 (24.43) Both liver and gastrointestinal diseases 187 (2.17) 64 (1.16) 123 (3.98) Note: BMI: Body Mass Index; * P < 0.05; ** P < 0.01; *** P < 0.001; 3.2 Relationships among Digestive Diseases, Nighttime Sleep Duration, and Depressive Symptoms We first conducted Spearman correlation analysis on the two groups of objects (see Table 2 ). The results showed that the prevalence of digestive diseases in the middle-aged and elderly was positively correlated with insufficient nighttime sleep and depressive symptoms (ρ1 = 0.124, P < 0.001; ρ2 = 0.156, P < 0.001), and insufficient nighttime sleep was also positively correlated with depressive symptoms (ρ3 = 0.212, P < 0.001). To further illustrate the relationships among digestive diseases, nighttime sleep duration, and depressive symptoms, we conducted a multivariate logistic regression analysis (see Table 3 ). The results showed that suffering from digestive diseases (OR = 1.55, 95% CI = 1.38, 1.73) and having insufficient nighttime sleep (OR = 2.17, 95% CI = 1.97, 2.40) were important risk factors for depressive symptoms in the middle-aged and elderly. Table 2 The correlations (ρ) among digestive diseases, insufficient nighttime sleep, and depressive symptoms Variables Digestive diseases Insufficient nighttime sleep Depressive symptoms Digestive diseases 1.000 Insufficient nighttime sleep 0.124 *** 1.000 Depressive symptoms 0.156 *** 0.212 *** 1.000 Note: *** P < 0.001. Table 3 The results of multivariate logistic regression analysis (OR and 95%CI) Variables Model 1 Model 2 Model 3 Digestive diseases (No) ref ref ref Yes 1.92 (1.73, 2.13) *** 1.83 (1.65, 2.04) *** 1.55 (1.38, 1.73) *** Nighttime sleep (≥ 6 h) ref ref Ref <6 h 2.40 (2.18, 2.64) *** 2.28 (2.06, 2.51) *** 2.17 (1.97, 2.40) *** Note: *** P < 0.001; Model 1: Crude model, without including other covariates; Model 2: Including variables such as demographic characteristics like age, gender, education level, marital status, place of residence, etc.; Model 3: Including the above demographic characteristic variables and also including lifestyle and chronic disease prevalence situations, such as smoking and drinking history, social activity participation, chronic pulmonary diseases, heart diseases, mental diseases, arthritis, etc. 3.3 Analysis of the Mediating Effect of Nighttime Sleep Duration between Digestive Diseases and Depressive Symptoms Taking demographic characteristics, lifestyle, and chronic disease prevalence situations as control variables, digestive diseases as independent variables, nighttime sleep duration as mediating variables, and depressive symptoms as dependent variables, a mediating effect model was established. The results showed (see Table 4 and Fig. 1 ) that suffering from digestive diseases was a significant positive predictor of insufficient nighttime sleep (a = 0.422, P < 0.001) and depressive symptoms (c = 0.110, P < 0.001), and insufficient nighttime sleep was also positively correlated with depressive symptoms (b = 0.038, P < 0.001). The total effect value c of digestive diseases on depressive symptoms was 0.110 (95% CI = 0.085, 0.135, P < 0.001), and the direct effect value c’ was 0.094 (95% CI = 0.071, 0.119, P < 0.001). Then, we used the non-parametric percentile Bootstrap test to test the mediating effect of nighttime sleep duration between digestive diseases and depressive symptoms in the middle-aged and elderly. By randomly sampling 5,000 times to construct the distribution of the mediating effect and calculate the 95% confidence interval, the results showed that the confidence interval did not include 0 and the above ab and c’ had the same sign, indicating that the partial mediating effect of insufficient nighttime sleep between digestive diseases and depressive symptoms in the middle-aged and elderly was established. The mediating effect value was 0.016 (95% CI = 0.011, 0.021, P < 0.001, accounting for 15% of the total effect). These results proved that digestive diseases partially mediated the occurrence of depressive symptoms through insufficient nighttime sleep. Table 4 The mediating effect of insufficient nighttime sleep between digestive diseases and depressive symptoms Effect type Effect (95%CI) Mediating effect (%) P Total effect 0.110 (0.085, 0.135) 100% < 0.001 Direct effect 0.094 (0.071, 0.119) 85% < 0.001 Indirect effect 0.016 (0.011, 0.021) 15% < 0.001 4. Discussion This study has conducted an in-depth and comprehensive analysis of the complex associations among digestive diseases, nighttime sleep duration, and depressive symptoms in the middle-aged and elderly population. The prevalence rate of digestive diseases obtained in this study was 23.05%, and the detection rate of depressive symptoms reached 35.90%, which was consistent with the epidemiological data of previous studies [ 2 , 4 , 5 ], clearly revealing the importance and prevalence of these health problems among the middle-aged and elderly population. Through Spearman correlation analysis and multivariate logistic regression analysis, we identified significant positive correlations among the three. Specifically, the presence of digestive diseases showed a positive correlation trend with insufficient nighttime sleep as well as depressive symptoms. Meanwhile, there was also an obvious positive correlation between insufficient nighttime sleep and depressive symptoms. These research findings echoed the conclusions of some previous studies [ 25 – 27 ] that had pointed out the associations between chronic diseases and depression. However, the uniqueness of this study lies in the fact that starting from the clinically observed phenomena and utilizing the data from the latest 2020 CHARLS database, we were the first to focus on the impact of the increasingly prevalent gastrointestinal and liver diseases on depression and further elucidated the mediating role played by nighttime sleep, thereby adding new and valuable insights to the existing knowledge system in this field. The partial mediating effect of insufficient nighttime sleep between digestive diseases and depressive symptoms has extremely important implications for clinical practice. For clinicians, this means that when dealing with patients who commonly have comorbid digestive diseases and depression in clinical settings, the treatment strategy should not be limited to the treatment of the digestive diseases themselves, but should extend to the key factor of the patient's sleep status. By taking effective measures to improve the patients' nighttime sleep quality and duration, it is expected to alleviate depressive symptoms and further comprehensively improve the patient's quality of life and mental health. For example, a series of targeted sleep intervention measures can be incorporated into the comprehensive treatment plan for digestive diseases [ 28 ], such as the appropriate application of anti-anxiety and depression medications that promote sleep (e.g., agomelatine, etc.), the implementation of sleep hygiene education to help patients understand the importance of good sleep habits and sleep environment for health, and the application of cognitive-behavioral therapy to improve sleep. By adjusting patients' cognitive patterns and behavioral habits, it is possible to correct the potentially adverse sleep behaviors and thinking patterns. Such a comprehensive treatment model may break the often-existing vicious cycle among digestive diseases, sleep disorders, and depressive symptoms, creating more favorable conditions for patients' recovery and promoting the comprehensive restoration and improvement of patients' physical and mental states. Although this study has achieved the above valuable results, we must also clearly recognize some inherent limitations of the study itself. Firstly, this study adopted a cross-sectional study design. Although this design can analyze and describe the relationships among different variables at a specific time point, it cannot clarify the chronological order of causal relationships [ 29 ]. Secondly, in this study, the assessment of digestive diseases solely relied on the patient's self-reported diagnostic information in the questionnaire. This assessment method has certain drawbacks because self-reports may be affected by multiple factors, such as the accuracy of patients' memories, their awareness of diseases, subjective biases, and possible concealment or exaggeration of their conditions, resulting in less accurate and objective diagnostic results. Finally, the measurement of sleep duration in this study was based on the patients' self-recall of the average situation in the past month. This measurement method has obvious limitations because individuals may have memory biases during the recall process and cannot accurately recall the daily sleep duration. Moreover, the one-month time span is relatively long, and various factors may affect sleep conditions during this period, making the recall results less accurate and stable. Therefore, future studies can consider adopting a longitudinal study design to conduct long-term follow-up observations on the research subjects and collect data at different time points, thereby more accurately revealing the causal associations and dynamic change processes among variables [ 30 ]. In addition, more objective medical examination data can be combined, such as blood biochemical index tests, imaging examination results, pathological diagnoses, etc., to more precisely define the types, severity, and development stages of digestive diseases, thereby providing a more reliable data basis for the study. This may require further improvement of the CHARLS database or the utilization of other new domestic and foreign databases. Regarding sleep duration, more objective sleep monitoring technologies [ 31 ], such as polysomnography, can be used in the future to comprehensively and accurately record various physiological indicators of patients during sleep, thereby providing more accurate data support for sleep research. In conclusion, this study has provided important empirical evidence and theoretical basis for an in-depth understanding of the relationships among digestive diseases, nighttime sleep, and depressive symptoms in the middle-aged and elderly population. Despite certain limitations, it has pointed out the direction for future studies. Subsequent studies need to overcome these limitations and further expand and deepen the exploration of these relationships, thereby continuously improving our understanding of this field, providing more effective support and guidance for improving the clinical management strategies for the middle-aged and elderly population, enhancing their overall health level and quality of life. Declarations Acknowledgments We would like to express our sincere gratitude to Peking University for providing data of CHARLS and to those involved in data collection and management. We also would like to thank MD. Chengnan Guo from the School of Public Health, University of Fudan, who provided insightful methodological advice throughout the study. Author contributions All authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by Congcong Cheng, Dinghui Guo, Xu Cao, Dingmin Wang, and Wenling Li. The first draft of the manuscript was written by Congcong Cheng, Bei Miao, and Sujuan Fei. All authors commented on previous versions of the manuscript. Data availability The National School of Development at Peking University provided the data sets in the China Health and Retirement Longitudinal Survey (http://charls.pku.edu.cn/). Ethics approval and consent to participate All participants provided written informed consent, and the protocol was approved by the Ethical Review Committee of Peking University (approval number: IRB00001052−11015). This study followed the Strengthening of the Reporting of Observational Studies in Epidemiology (STROBE) reporting guideline. Statement of human and animal rights All procedures performed in this study involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards. 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Scott AJ, Correa AB, Bisby MA, Dear BF. Depression and Anxiety Trajectories in Chronic Disease: A Systematic Review and Meta-Analysis. Psychother Psychosom. 2023;92:227–42. Maier A, Riedel-Heller SG, Pabst A, Luppa M. Risk factors and protective factors of depression in older people 65+. A systematic review. PLoS One. 2021;16:e0251326. Sun S-Y, Chen G-H. Treatment of Circadian Rhythm Sleep-Wake Disorders. Curr Neuropharmacol. 2022;20:1022–34. Wang X, Cheng Z. Cross-Sectional Studies: Strengths, Weaknesses, and Recommendations. Chest. 2020;158:S65–71. Wang X, Kattan MW. Cohort Studies: Design, Analysis, and Reporting. Chest. 2020;158:S72–8. Yin J, Xu J, Ren T-L. Recent Progress in Long-Term Sleep Monitoring Technology. Biosensors (Basel). 2023;13:395. Additional Declarations No competing interests reported. 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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-5881924","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":406907095,"identity":"31a46c5e-1607-4fe4-85c1-a68596e05e16","order_by":0,"name":"Congcong Cheng","email":"","orcid":"","institution":"The Affiliated Hospital of Xuzhou Medical University","correspondingAuthor":false,"prefix":"","firstName":"Congcong","middleName":"","lastName":"Cheng","suffix":""},{"id":406907096,"identity":"fa913aaa-0151-4381-bf89-b7ebd6c6617f","order_by":1,"name":"Dinghui Guo","email":"","orcid":"","institution":"The Affiliated Hospital of Xuzhou Medical University","correspondingAuthor":false,"prefix":"","firstName":"Dinghui","middleName":"","lastName":"Guo","suffix":""},{"id":406907097,"identity":"86d94f73-6e30-4b49-81b3-55874ef4affa","order_by":2,"name":"Xu Cao","email":"","orcid":"","institution":"The Affiliated Hospital of Xuzhou Medical University","correspondingAuthor":false,"prefix":"","firstName":"Xu","middleName":"","lastName":"Cao","suffix":""},{"id":406907098,"identity":"0fb38c7a-45a6-4793-873d-0078212cde48","order_by":3,"name":"Dingmin Wang","email":"","orcid":"","institution":"The Affiliated Hospital of Xuzhou Medical University","correspondingAuthor":false,"prefix":"","firstName":"Dingmin","middleName":"","lastName":"Wang","suffix":""},{"id":406907099,"identity":"11f43e07-e098-4557-aea2-1d15be697dc1","order_by":4,"name":"Wenling Li","email":"","orcid":"","institution":"The Affiliated Hospital of Xuzhou Medical University","correspondingAuthor":false,"prefix":"","firstName":"Wenling","middleName":"","lastName":"Li","suffix":""},{"id":406907100,"identity":"fa864473-387a-46ad-bea4-316dd4bb87f3","order_by":5,"name":"Bei Miao","email":"","orcid":"","institution":"The Affiliated Hospital of Xuzhou Medical University","correspondingAuthor":false,"prefix":"","firstName":"Bei","middleName":"","lastName":"Miao","suffix":""},{"id":406907101,"identity":"08eb3fe7-9dec-437c-b2ca-489231ac6133","order_by":6,"name":"Sujuan Fei","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABDklEQVRIie3OMUvDQBTA8TsOLstVB5crFfMJhDsK0SHSr3Ih0Km4CJKpXAk8l4JrBv0OTgG3hA5dDuduJrgqZBUFbeJoEjJ2uP/4eD/eQ8hmO8Bmr6XOKuEzSvCqqBBSzZj1mSzMyySanx45JJbJMDIPp8xs/LNjB07YEIK18fgISP0YkCtYXp8nChcfgNyLDkLw2uNjoA15Wxh64+0UkY+A5LNuJ5Qwj0tgNbmbLiIWpDtFJyNASmTthNE9CYA3VyaXgtfE+eoj+91QZEb8ERSJ5grpI4KTvNSRqkks10YFqSnj8cMLl0+dBOvNt/iZuffbsviEZZBuw7x6v/XdrittYV1/PHzfZrPZbP/6BfPJV2s2vrEZAAAAAElFTkSuQmCC","orcid":"","institution":"The Affiliated Hospital of Xuzhou Medical University","correspondingAuthor":true,"prefix":"","firstName":"Sujuan","middleName":"","lastName":"Fei","suffix":""}],"badges":[],"createdAt":"2025-01-22 15:08:15","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5881924/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5881924/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":74960559,"identity":"3c42e5db-d681-4e3e-be3b-a99a407728c1","added_by":"auto","created_at":"2025-01-28 18:52:01","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":29002,"visible":true,"origin":"","legend":"\u003cp\u003eMediation effect model and effect values\u003c/p\u003e\n\u003cp\u003eNote: \u003csup\u003e***\u003c/sup\u003eP \u0026lt; 0.001.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-5881924/v1/dbedafde8c015850bde67fd7.png"},{"id":76409363,"identity":"5911f096-4ecd-43c5-8171-e3b7da78ffba","added_by":"auto","created_at":"2025-02-16 23:46:26","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1109330,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5881924/v1/108e0469-f73e-4856-9cfa-63b8f3a92f11.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Association between Digestive Diseases, Nighttime Sleep, and Depressive Symptoms among the Middle-aged and Elderly Adults: A Mediation Analysis","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eWith the acceleration of the population aging process and lifestyle change, the health issues of middle-aged and elderly adults have received extensive attention. On the one hand, due to the degeneration of physical functions, middle-aged and elderly adults often suffer from digestive diseases. Because of their multiplicity and recurrence, patients usually develop depressive emotions over time [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. A study analyzed the global burden of digestive diseases from 1990 to 2019 [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. The data showed that the prevalence rate of digestive diseases was 35% in 2019, accounting for a large part of the total disease burden. Among them, intestinal infections had the highest mortality rate, while chronic liver diseases had the highest prevalence rate. Digestive diseases are often accompanied by discomfort such as indigestion, abdominal pain, and abdominal distension, which seriously affect patients' quality of life and daily activity ability, bringing physical pain and psychological pressure to patients [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. At this time, depression often follows. Studies have shown that the prevalence rate of depression in patients with inflammatory bowel disease is 25.2% [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]; in addition, among the patients in the gastroenterology department, the total detection rate of simple depressive symptoms is 31.11% [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Depression not only leads to psychological problems such as low mood, loss of interest, and sleep disorders but also weakens the body's immune function, increasing the risk of chronic diseases and the possibility of disease progression [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e], thus forming a vicious cycle, that seriously affects the physical and mental health and quality of life of middle-aged and elderly adults.\u003c/p\u003e \u003cp\u003ePrevious studies [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e] have shown that sleep quality plays a crucial role in the physiological and psychological regulation of the human body, especially for middle-aged and elderly adults. Nighttime sleep, as a key component of sleep, changes in its duration and quality are closely related to various health problems [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. When middle-aged and elderly adults suffer from digestive diseases, they may frequently wake up due to physical discomfort such as nighttime abdominal pain, abdominal distension, and acid reflux, or have difficulty falling asleep due to worry and anxiety about the disease, thereby affecting nighttime sleep [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Sleep disorders may further interfere with the normal function of the neuroendocrine system, and affect the balance of neurotransmitters, thereby increasing the risk of depressive symptoms [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eHowever, there are still deficiencies in the current research on the internal relationship among digestive diseases, nighttime sleep, and depressive symptoms in middle-aged and elderly adults. Most studies only focus on the simple association between the two, lacking in-depth exploration of the complex mechanism of action among the three [\u003cspan additionalcitationids=\"CR14 CR15 CR16\" citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. In addition, the existing studies mostly focus on specific regions or small-scale populations in sample selection, lacking nationwide large sample data support with broad representativeness, making it difficult to comprehensively and accurately reflect the real situation of the middle-aged and elderly population in China.\u003c/p\u003e \u003cp\u003eThe China Health and Retirement Longitudinal Study (CHARLS) adopts stratified multi-stage probability sampling to recruit people aged 45 and above from nationally representative regions and widely collects personal and family information, providing an excellent data basis for studying aging issues [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Based on the CHARLS database, this study deeply analyzes the impact of digestive diseases on depressive symptoms in middle-aged and elderly adults, focuses on exploring the mediating effect and its magnitude of nighttime sleep duration, in order to provide more comprehensive clinical management for gastroenterology patients with comorbid depressive symptoms, contribute to the development of healthy aging, and improve the quality of life and happiness of middle-aged and elderly adults.\u003c/p\u003e"},{"header":"2. Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1 Data Source\u003c/h2\u003e \u003cp\u003eThis study utilized the data of the China Health and Retirement Longitudinal Study (CHARLS) from 2015 to 2020. CHARLS is a large-scale population cohort study with the middle-aged and elderly in China as the research objects. It is representative of the middle-aged and elderly population in China. This survey has been approved by the Biomedical Ethics Committee of Peking University (IRB00001052-11015), and all survey subjects signed the informed consent form. In this study, the middle-aged and elderly aged\u0026thinsp;\u0026ge;\u0026thinsp;45 were selected as the research objects, and those with missing variable data such as digestive diseases, nighttime sleep duration, and depressive symptoms were deleted. A total of 8,610 research objects were included.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2 Research Variables\u003c/h2\u003e \u003cdiv id=\"Sec5\" class=\"Section3\"\u003e \u003ch2\u003e2.2.1 Definition of Digestive Diseases\u003c/h2\u003e \u003cp\u003eIt mainly includes gastrointestinal diseases and liver diseases mentioned in the questionnaire. It was determined whether a person suffered from such diseases according to the two questions: \"Have you been diagnosed by a doctor as having gastrointestinal diseases?\" and \"Have you been diagnosed by a doctor as having liver diseases?\". If a person neither suffered from gastrointestinal diseases nor liver diseases, the digestive diseases were assigned a value of \"0\", otherwise, it was assigned a value of \"1\".\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section3\"\u003e \u003ch2\u003e2.2.2 Measurement of Nighttime Sleep Duration\u003c/h2\u003e \u003cp\u003eIt was obtained by extracting the question in the questionnaire: \"In the past month, how many hours did the respondent enter and maintain the sleep state on average every night?\". If the nighttime sleep duration was \u0026lt;\u0026thinsp;6 hours [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e], it was regarded as insufficient nighttime sleep and assigned a value of \"1\", otherwise, it was assigned a value of \"0\".\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section3\"\u003e \u003ch2\u003e2.2.3 Definition of Depressive Symptoms\u003c/h2\u003e \u003cp\u003eThe 10 items in the Center for Epidemiologic Studies Depression Scale (CES-D10) [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e] were used to detect depressive symptoms in the elderly. Each item in the scale contained 4 options, and each option was scored 0, 1, 2, and 3 points in turn. Questions 5 and 8 were reverse-scored because they were positive emotions. The total score ranged from 0 to 30 points. The higher the CES-D10 score, the more severe the depressive symptoms. In this study, the respondents with a cumulative CES-D10 score\u0026thinsp;\u0026ge;\u0026thinsp;10 points [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e] were defined as having depressive symptoms and assigned a value of \"1\", otherwise, it was assigned a value of \"0\".\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section3\"\u003e \u003ch2\u003e2.2.4 Selection of Covariates\u003c/h2\u003e \u003cp\u003eDemographic characteristics of the research objects, including gender, age, education level, place of residence, marital status, lifestyle habits such as smoking history, drinking history, social activity participation, body mass index (BMI), and the situation of chronic diseases, including hypertension, diabetes, cancer, chronic pulmonary diseases, heart diseases, mental diseases, arthritis, etc., were obtained from the questionnaire.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003e2.3 Statistical Analysis\u003c/h2\u003e \u003cp\u003eRStudio was used for data cleaning and statistical analysis. The research objects were divided into two groups according to the presence or absence of depressive symptoms, and their characteristics were described. Categorical variables were expressed as numbers (%). The chi-square test was used for inter-group difference analysis. Multivariate logistic regression analysis and Spearman correlation analysis were used to explore the relationships among digestive diseases, nighttime sleep, and depressive symptoms. The \"mediation\" package in RStudio was used to establish a mediation model to analyze the mediating effect of nighttime sleep between digestive diseases and depressive symptoms, and the bias-corrected percentile Bootstrap method was used for testing [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. P\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant.\u003c/p\u003e \u003c/div\u003e"},{"header":"3. Results","content":"\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003e3.1 Basic Information of Research Objects\u003c/h2\u003e \u003cp\u003eAs shown in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, a total of 8,610 middle-aged and elderly people were included as research objects in this study. Among them, 3,091 cases (35.90%) had depressive symptoms detected, and 5,519 cases (64.10%) did not; 2,685 cases (31.18%) had a nighttime sleep duration of \u0026lt;\u0026thinsp;6 hours, while 5,925 cases (68.82%) had a nighttime sleep duration of \u0026ge;\u0026thinsp;6 hours; in terms of digestive diseases, 6,625 cases (76.95%) had no digestive diseases, 234 cases (2.72%) had only liver diseases, 1,564 cases (18.16%) had only gastrointestinal diseases, and 187 cases (2.17%) had both diseases. The prevalence rate of digestive diseases was 23.05%. Taking depressive symptoms as a categorical variable, the difference test was performed on the two groups of research objects. The results showed that the differences in variables such as age, gender, education level, marital status, place of residence, BMI, smoking history, drinking history, social activity participation, nighttime sleep duration, hypertension, diabetes, chronic pulmonary diseases, heart diseases, mental diseases, arthritis, and digestive diseases between the two groups of research objects were statistically significant (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05), while the difference in cancer between the two groups was not significant (P\u0026thinsp;=\u0026thinsp;0.39). Compared with the non-depressive group, the middle-aged and elderly with depressive symptoms detected had shorter nighttime sleep and a higher prevalence rate of digestive diseases.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eBasic information of research subjects and difference tests [n (%)]\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;8610)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNon-depressive\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;5519)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDepressive\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;3091)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eχ\u0026sup2;\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge group, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e20.70\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt;60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e4761 (55.30)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e3142 (56.93)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1619 (52.38)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e60\u0026thinsp;~\u0026thinsp;70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2777 (32.25)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1688 (30.59)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1089 (35.23)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026gt;70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1072 (12.45)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e689 (12.48)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e383 (12.39)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003esex, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e230.21\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFemale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e6500 (75.49)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e3876 (70.23)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2624 (84.89)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2110 (24.51)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1643 (29.77)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e467 (15.11)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEducational level, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e43.35\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIlliterate\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e635 (7.38)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e359 (6.50)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e276 (8.93)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePrimary school-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e899 (10.44)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e537 (9.73)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e362 (11.71)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMiddle school\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e380 (4.41)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e284 (5.15)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e96 (3.11)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHigh school+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e6696 (77.77)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4339 (78.62)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2357 (76.25)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMarital, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e73.81\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMarried\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e7587 (88.12)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4987 (90.36)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2600 (84.12)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSingle\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1023 (11.88)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e532 (9.64)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e491 (15.88)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eResidence, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e116.49\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRural\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e6926 (80.44)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4249 (76.99)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2677 (86.61)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eUrban\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1684 (19.56)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1270 (23.01)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e414 (13.39)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBMI (kg/m\u003csup\u003e2\u003c/sup\u003e), n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e7.63\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt;18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e254 (2.95)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e144 (2.61)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e110 (3.56)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e18\u0026thinsp;~\u0026thinsp;28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e7022 (81.56)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4498 (81.50)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2524 (81.66)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026gt;28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1334 (15.49)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e877 (15.89)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e457 (14.78)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSmoking history, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e55.18\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e7623 (88.54)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4781 (86.63)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2842 (91.94)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e987 (11.46)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e738 (13.37)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e249 (8.06)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDrinking history, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e45.51\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e7124 (82.74)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4453 (80.68)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2671 (86.41)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1486 (17.26)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1066 (19.32)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e420 (13.59)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSocial activities, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e51.38\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e4809 (55.85)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e3241 (58.72)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1568 (50.73)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e3801 (44.15)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e2278 (41.28)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1523 (49.27)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNighttime sleep, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e387.83\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt; 6 h\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2685 (31.18)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1315 (23.83)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1370 (44.32)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026ge; 6 h\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e5925 (68.82)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4204 (76.17)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1721 (55.68)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHypertension, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e11.99\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e6448 (74.89)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4200 (76.10)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2248 (72.73)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2162 (25.11)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1319 (23.90)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e843 (27.27)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDiabetes, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e11.02\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e7992 (92.82)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e5161 (93.51)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2831 (91.59)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e618 (7.18)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e358 (6.49)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e260 (8.41)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCancer, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.39\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e8523 (98.99)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e5466 (99.04)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e3057 (98.90)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e87 (1.01)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e53 (0.96)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e34 (1.10)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChronic lung diseases, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e105.35\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e7996 (92.87)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e5243 (95.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2753 (89.07)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e614 (7.13)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e276 (5.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e338 (10.93)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHeart diseases, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e47.37\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e7538 (87.55)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4933 (89.38)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2605 (84.28)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1072 (12.45)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e586 (10.62)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e486 (15.72)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMental diseases, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e41.39\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e8536 (99.14)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e5498 (99.62)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e3038 (98.29)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e74 (0.86)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e21 (0.38)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e53 (1.71)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eArthritis, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e278.64\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e6132 (71.22)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4267 (77.31)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1865 (60.34)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2478 (28.78)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1252 (22.69)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1226 (39.66)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDigestive diseases, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e209.54\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e6625 (76.95)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4518 (81.86)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2107 (68.17)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOnly liver diseases\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e234 (2.72)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e128 (2.32)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e106 (3.43)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOnly gastrointestinal diseases\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1564 (18.16)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e809 (14.66)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e755 (24.43)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBoth liver and gastrointestinal diseases\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e187 (2.17)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e64 (1.16)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e123 (3.98)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eNote: BMI: Body Mass Index; \u003csup\u003e*\u003c/sup\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.05; \u003csup\u003e**\u003c/sup\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.01; \u003csup\u003e***\u003c/sup\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.001;\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003e3.2 Relationships among Digestive Diseases, Nighttime Sleep Duration, and Depressive Symptoms\u003c/h2\u003e \u003cp\u003eWe first conducted Spearman correlation analysis on the two groups of objects (see Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The results showed that the prevalence of digestive diseases in the middle-aged and elderly was positively correlated with insufficient nighttime sleep and depressive symptoms (ρ1\u0026thinsp;=\u0026thinsp;0.124, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001; ρ2\u0026thinsp;=\u0026thinsp;0.156, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), and insufficient nighttime sleep was also positively correlated with depressive symptoms (ρ3\u0026thinsp;=\u0026thinsp;0.212, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001). To further illustrate the relationships among digestive diseases, nighttime sleep duration, and depressive symptoms, we conducted a multivariate logistic regression analysis (see Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). The results showed that suffering from digestive diseases (OR\u0026thinsp;=\u0026thinsp;1.55, 95% CI\u0026thinsp;=\u0026thinsp;1.38, 1.73) and having insufficient nighttime sleep (OR\u0026thinsp;=\u0026thinsp;2.17, 95% CI\u0026thinsp;=\u0026thinsp;1.97, 2.40) were important risk factors for depressive symptoms in the middle-aged and elderly.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eThe correlations (ρ) among digestive diseases, insufficient nighttime sleep, and depressive symptoms\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDigestive diseases\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eInsufficient nighttime sleep\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDepressive symptoms\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDigestive diseases\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1.000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eInsufficient nighttime sleep\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.124\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1.000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDepressive symptoms\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.156\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.212\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eNote: \u003csup\u003e***\u003c/sup\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.001.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eThe results of multivariate logistic regression analysis (OR and 95%CI)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eModel 1\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eModel 2\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eModel 3\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDigestive diseases (No)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eref\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eref\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eref\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.92 (1.73, 2.13) \u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.83 (1.65, 2.04) \u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.55 (1.38, 1.73) \u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNighttime sleep (\u0026ge;\u0026thinsp;6 h)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eref\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eref\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eRef\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt;6 h\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.40 (2.18, 2.64) \u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.28 (2.06, 2.51) \u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.17 (1.97, 2.40) \u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eNote: \u003csup\u003e***\u003c/sup\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.001;\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eModel 1: Crude model, without including other covariates;\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eModel 2: Including variables such as demographic characteristics like age, gender, education level, marital status, place of residence, etc.;\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eModel 3: Including the above demographic characteristic variables and also including lifestyle and chronic disease prevalence situations, such as smoking and drinking history, social activity participation, chronic pulmonary diseases, heart diseases, mental diseases, arthritis, etc.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003e3.3 Analysis of the Mediating Effect of Nighttime Sleep Duration between Digestive Diseases and Depressive Symptoms\u003c/h2\u003e \u003cp\u003eTaking demographic characteristics, lifestyle, and chronic disease prevalence situations as control variables, digestive diseases as independent variables, nighttime sleep duration as mediating variables, and depressive symptoms as dependent variables, a mediating effect model was established. The results showed (see Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e) that suffering from digestive diseases was a significant positive predictor of insufficient nighttime sleep (a\u0026thinsp;=\u0026thinsp;0.422, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001) and depressive symptoms (c\u0026thinsp;=\u0026thinsp;0.110, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), and insufficient nighttime sleep was also positively correlated with depressive symptoms (b\u0026thinsp;=\u0026thinsp;0.038, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001). The total effect value c of digestive diseases on depressive symptoms was 0.110 (95% CI\u0026thinsp;=\u0026thinsp;0.085, 0.135, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), and the direct effect value c\u0026rsquo; was 0.094 (95% CI\u0026thinsp;=\u0026thinsp;0.071, 0.119, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Then, we used the non-parametric percentile Bootstrap test to test the mediating effect of nighttime sleep duration between digestive diseases and depressive symptoms in the middle-aged and elderly. By randomly sampling 5,000 times to construct the distribution of the mediating effect and calculate the 95% confidence interval, the results showed that the confidence interval did not include 0 and the above ab and c\u0026rsquo; had the same sign, indicating that the partial mediating effect of insufficient nighttime sleep between digestive diseases and depressive symptoms in the middle-aged and elderly was established. The mediating effect value was 0.016 (95% CI\u0026thinsp;=\u0026thinsp;0.011, 0.021, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001, accounting for 15% of the total effect). These results proved that digestive diseases partially mediated the occurrence of depressive symptoms through insufficient nighttime sleep.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eThe mediating effect of insufficient nighttime sleep between digestive diseases and depressive symptoms\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEffect type\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eEffect (95%CI)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMediating effect (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal effect\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.110 (0.085, 0.135)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDirect effect\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.094 (0.071, 0.119)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e85%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIndirect effect\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.016 (0.011, 0.021)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e15%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"4. Discussion","content":"\u003cp\u003eThis study has conducted an in-depth and comprehensive analysis of the complex associations among digestive diseases, nighttime sleep duration, and depressive symptoms in the middle-aged and elderly population. The prevalence rate of digestive diseases obtained in this study was 23.05%, and the detection rate of depressive symptoms reached 35.90%, which was consistent with the epidemiological data of previous studies [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e], clearly revealing the importance and prevalence of these health problems among the middle-aged and elderly population.\u003c/p\u003e \u003cp\u003eThrough Spearman correlation analysis and multivariate logistic regression analysis, we identified significant positive correlations among the three. Specifically, the presence of digestive diseases showed a positive correlation trend with insufficient nighttime sleep as well as depressive symptoms. Meanwhile, there was also an obvious positive correlation between insufficient nighttime sleep and depressive symptoms. These research findings echoed the conclusions of some previous studies [\u003cspan additionalcitationids=\"CR26\" citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e] that had pointed out the associations between chronic diseases and depression. However, the uniqueness of this study lies in the fact that starting from the clinically observed phenomena and utilizing the data from the latest 2020 CHARLS database, we were the first to focus on the impact of the increasingly prevalent gastrointestinal and liver diseases on depression and further elucidated the mediating role played by nighttime sleep, thereby adding new and valuable insights to the existing knowledge system in this field.\u003c/p\u003e \u003cp\u003eThe partial mediating effect of insufficient nighttime sleep between digestive diseases and depressive symptoms has extremely important implications for clinical practice. For clinicians, this means that when dealing with patients who commonly have comorbid digestive diseases and depression in clinical settings, the treatment strategy should not be limited to the treatment of the digestive diseases themselves, but should extend to the key factor of the patient's sleep status. By taking effective measures to improve the patients' nighttime sleep quality and duration, it is expected to alleviate depressive symptoms and further comprehensively improve the patient's quality of life and mental health. For example, a series of targeted sleep intervention measures can be incorporated into the comprehensive treatment plan for digestive diseases [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e], such as the appropriate application of anti-anxiety and depression medications that promote sleep (e.g., agomelatine, etc.), the implementation of sleep hygiene education to help patients understand the importance of good sleep habits and sleep environment for health, and the application of cognitive-behavioral therapy to improve sleep. By adjusting patients' cognitive patterns and behavioral habits, it is possible to correct the potentially adverse sleep behaviors and thinking patterns. Such a comprehensive treatment model may break the often-existing vicious cycle among digestive diseases, sleep disorders, and depressive symptoms, creating more favorable conditions for patients' recovery and promoting the comprehensive restoration and improvement of patients' physical and mental states.\u003c/p\u003e \u003cp\u003eAlthough this study has achieved the above valuable results, we must also clearly recognize some inherent limitations of the study itself. Firstly, this study adopted a cross-sectional study design. Although this design can analyze and describe the relationships among different variables at a specific time point, it cannot clarify the chronological order of causal relationships [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. Secondly, in this study, the assessment of digestive diseases solely relied on the patient's self-reported diagnostic information in the questionnaire. This assessment method has certain drawbacks because self-reports may be affected by multiple factors, such as the accuracy of patients' memories, their awareness of diseases, subjective biases, and possible concealment or exaggeration of their conditions, resulting in less accurate and objective diagnostic results. Finally, the measurement of sleep duration in this study was based on the patients' self-recall of the average situation in the past month. This measurement method has obvious limitations because individuals may have memory biases during the recall process and cannot accurately recall the daily sleep duration. Moreover, the one-month time span is relatively long, and various factors may affect sleep conditions during this period, making the recall results less accurate and stable.\u003c/p\u003e \u003cp\u003eTherefore, future studies can consider adopting a longitudinal study design to conduct long-term follow-up observations on the research subjects and collect data at different time points, thereby more accurately revealing the causal associations and dynamic change processes among variables [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. In addition, more objective medical examination data can be combined, such as blood biochemical index tests, imaging examination results, pathological diagnoses, etc., to more precisely define the types, severity, and development stages of digestive diseases, thereby providing a more reliable data basis for the study. This may require further improvement of the CHARLS database or the utilization of other new domestic and foreign databases. Regarding sleep duration, more objective sleep monitoring technologies [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e], such as polysomnography, can be used in the future to comprehensively and accurately record various physiological indicators of patients during sleep, thereby providing more accurate data support for sleep research.\u003c/p\u003e \u003cp\u003eIn conclusion, this study has provided important empirical evidence and theoretical basis for an in-depth understanding of the relationships among digestive diseases, nighttime sleep, and depressive symptoms in the middle-aged and elderly population. Despite certain limitations, it has pointed out the direction for future studies. Subsequent studies need to overcome these limitations and further expand and deepen the exploration of these relationships, thereby continuously improving our understanding of this field, providing more effective support and guidance for improving the clinical management strategies for the middle-aged and elderly population, enhancing their overall health level and quality of life.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe would like to express our sincere gratitude to Peking University for providing data of CHARLS and to those involved in data collection and management. We also would like to thank MD. Chengnan Guo from the School of Public Health, University of Fudan, who provided insightful methodological advice throughout the study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by Congcong Cheng, Dinghui Guo, Xu Cao, Dingmin Wang, and Wenling Li. The first draft of the manuscript was written by Congcong Cheng, Bei Miao, and Sujuan Fei. All authors commented on previous versions of the manuscript.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe National School of Development at Peking University provided the data sets in the China Health and Retirement Longitudinal Survey (http://charls.pku.edu.cn/).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll participants provided written informed consent, and the protocol was approved by the Ethical Review Committee of Peking University (approval number: IRB00001052\u0026minus;11015). This study followed the Strengthening of the Reporting of Observational Studies in Epidemiology (STROBE) reporting guideline.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatement of human and animal rights\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll procedures performed in this study involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they did not receive any funding from any source.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eLiang J, Zhao Y, Xi Y, Xiang C, Yong C, Huo J, et al. Association between Depression, Anxiety Symptoms and Gut Microbiota in Chinese Elderly with Functional Constipation. Nutrients. 2022;14:5013.\u003c/li\u003e\n\u003cli\u003eWang Y, Huang Y, Chase RC, Li T, Ramai D, Li S, et al. Global Burden of Digestive Diseases: A Systematic Analysis of the Global Burden of Diseases Study, 1990 to 2019. Gastroenterology. 2023;165:773-783.e15.\u003c/li\u003e\n\u003cli\u003ePeng J, Xu H, Huang S, Shi X, Wang P, Chen Q, et al. Comparison of the burden of digestive diseases between China and the United States from 1990 to 2019. Front Public Health. 2024;12:1376406.\u003c/li\u003e\n\u003cli\u003eBarberio B, Zamani M, Black CJ, Savarino EV, Ford AC. Prevalence of symptoms of anxiety and depression in patients with inflammatory bowel disease: a systematic review and meta-analysis. Lancet Gastroenterol Hepatol. 2021;6:359\u0026ndash;70.\u003c/li\u003e\n\u003cli\u003eZhang A-Z, Wang Q-C, Huang K-M, Huang J-G, Zhou C-H, Sun F-Q, et al. 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The role of insufficient sleep and circadian misalignment in obesity. Nat Rev Endocrinol. 2023;19:82\u0026ndash;97.\u003c/li\u003e\n\u003cli\u003eFjell AM, Walhovd KB. Individual sleep need is flexible and dynamically related to cognitive function. Nat Hum Behav. 2024;8:422\u0026ndash;30.\u003c/li\u003e\n\u003cli\u003eVernia F, Di Ruscio M, Ciccone A, Viscido A, Frieri G, Stefanelli G, et al. Sleep disorders related to nutrition and digestive diseases: a neglected clinical condition. Int J Med Sci. 2021;18:593\u0026ndash;603.\u003c/li\u003e\n\u003cli\u003ePlante DT. The Evolving Nexus of Sleep and Depression. Am J Psychiatry. 2021;178:896\u0026ndash;902.\u003c/li\u003e\n\u003cli\u003eDong L, Xie Y, Zou X. Association between sleep duration and depression in US adults: A cross-sectional study. J Affect Disord. 2022;296:183\u0026ndash;8.\u003c/li\u003e\n\u003cli\u003eNielson SA, Kay DB, Dzierzewski JM. Sleep and Depression in Older Adults: A Narrative Review. Curr Psychiatry Rep. 2023;25:643\u0026ndash;58.\u003c/li\u003e\n\u003cli\u003eWang B, Xiong Y, Li R, Zhang S. Depression increases the risk of gallstone: A cross-sectional study and Mendelian randomization analysis. J Affect Disord. 2024;362:606\u0026ndash;14.\u003c/li\u003e\n\u003cli\u003eQu Y, Nie D, Song Y, Cai X, Gong Y, Chen S, et al. Bibliometric analysis of research on digestive system tumors and depression. Front Psychol. 2024;15:1414528.\u003c/li\u003e\n\u003cli\u003eOrr WC, Fass R, Sundaram SS, Scheimann AO. The effect of sleep on gastrointestinal functioning in common digestive diseases. Lancet Gastroenterol Hepatol. 2020;5:616\u0026ndash;24.\u003c/li\u003e\n\u003cli\u003eZhao Y, Hu Y, Smith JP, Strauss J, Yang G. Cohort profile: the China Health and Retirement Longitudinal Study (CHARLS). Int J Epidemiol. 2014;43:61\u0026ndash;8.\u003c/li\u003e\n\u003cli\u003eEmilsson \u0026Ouml;I, Al Yasiry H, Theorell-Hagl\u0026ouml;w J, Ljunggren M, Lindberg E. 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Risk factors and protective factors of depression in older people 65+. A systematic review. PLoS One. 2021;16:e0251326.\u003c/li\u003e\n\u003cli\u003eSun S-Y, Chen G-H. Treatment of Circadian Rhythm Sleep-Wake Disorders. Curr Neuropharmacol. 2022;20:1022\u0026ndash;34.\u003c/li\u003e\n\u003cli\u003eWang X, Cheng Z. Cross-Sectional Studies: Strengths, Weaknesses, and Recommendations. Chest. 2020;158:S65\u0026ndash;71.\u003c/li\u003e\n\u003cli\u003eWang X, Kattan MW. Cohort Studies: Design, Analysis, and Reporting. Chest. 2020;158:S72\u0026ndash;8.\u003c/li\u003e\n\u003cli\u003eYin J, Xu J, Ren T-L. Recent Progress in Long-Term Sleep Monitoring Technology. Biosensors (Basel). 2023;13:395.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Digestive diseases, Depressive symptoms, Nighttime sleep duration, Mediating effect, Middle-aged and elderly adults","lastPublishedDoi":"10.21203/rs.3.rs-5881924/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5881924/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackgrounds:\u003c/h2\u003e \u003cp\u003eAs the population ages, the relationship among digestive diseases, nighttime sleep duration, and depressive symptoms in middle-aged and elderly adults, especially sleep's mediating role, remains unclear, thus prompting research.\u003c/p\u003e\u003ch2\u003eAims\u003c/h2\u003e \u003cp\u003eTo explore how nighttime sleep duration mediates between digestive diseases and depressive symptoms in this group, aiming to guide clinical treatment of related depression.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eUsing 2015\u0026ndash;2020 China Health and Retirement Longitudinal Study (CHARLS) data, we applied difference, Spearman correlation, and multivariate logistic regression analyses. A mediating effect model was set up and tested via the Bootstrap method.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eDigestive diseases had a 23.05% prevalence rate, and depressive symptoms had a 35.90% detection rate. Both digestive diseases (OR\u0026thinsp;=\u0026thinsp;1.55, 95% CI: 1.38\u0026ndash;1.73) and insufficient nighttime sleep (OR\u0026thinsp;=\u0026thinsp;2.17, 95% CI: 1.97\u0026ndash;2.40) significantly affected depressive symptoms. The model showed that insufficient nighttime sleep had a partial mediating effect.\u003c/p\u003e\u003ch2\u003eDiscussion\u003c/h2\u003e \u003cp\u003eClinically, treating relevant patients requires a holistic approach with an emphasis on sleep. Future research should use objective measures and longitudinal studies to clarify mechanisms and causalities.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eDigestive diseases can cause insufficient sleep, promoting depressive symptoms. Clinicians should not overlook sleep quality when treating digestive patients with comorbid depression, as improving sleep may relieve symptoms.\u003c/p\u003e","manuscriptTitle":"Association between Digestive Diseases, Nighttime Sleep, and Depressive Symptoms among the Middle-aged and Elderly Adults: A Mediation Analysis","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-01-28 18:51:56","doi":"10.21203/rs.3.rs-5881924/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"a6c27a35-1e64-4605-887f-b4087380b348","owner":[],"postedDate":"January 28th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-02-16T23:38:19+00:00","versionOfRecord":[],"versionCreatedAt":"2025-01-28 18:51:56","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5881924","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5881924","identity":"rs-5881924","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}