Abstract
BACKGROUND: The prevalence of late-life depression (LLD) is high, and its most dangerous, serious, and fatal comorbidity is suicide. Therefore, the present study systematically investigates the risk factors for suicide in individuals with LLD, offering empirical support for the development of preventive interventions against suicidal behavior. METHODS: PubMed, Web of Science, the Cochrane Library, PsycInfo, CNKI, Wan Fang Data, VIP, and CBM databases were searched from the inception of each database to February 2025 to identify observational studies of risk factors for suicide in LLD patients. The Newcastle-Ottawa Scale (NOS) and the Agency for Healthcare Research and Quality (AHRQ) were used to ensure study quality. Stata 18.0 software was used to perform a meta-analysis and sensitivity analysis to compute the pooled odds ratio. RESULTS: A total of 12 studies (eight case-control, two cross-sectional, and two longitudinal studies), with a quality level of medium or above, were included in the analysis. Depression severity (OR = 3.485, 95% CI: 1.385 to 8.769, P = 0.008) was identified as a significant risk factor for suicide in LLD. The age of onset (OR = 0.969, 95% CI: 0.905 to 1.039, P = 0.378) was not statistically significant for the risk of suicide in LLD. The descriptive analysis revealed that suicidal ideation, educational level, N3 sleep duration, odor identification dysfunction, alcohol drinking history, cognitive function, history of major trauma, history of suicide attempts, and high-density lipoprotein were associated with an increased suicide risk in LLD. CONCLUSION: Our meta-analysis has revealed a variety of factors influencing suicide risk in LLD patients. Clinical staff should strengthen the assessment and screening of risk factors and take timely intervention and targeted treatment to reduce the risk of suicide in LLD. SYSTEMATIC REVIEW REGISTRATION: https://www.crd.york.ac.uk/prospero/, identifier CRD420251040029.