1139 Effect of Sleep Duration Intervention on Suicide Attempts in Patients with Psychiatric Disorders: A Target Trial Emulation

Abstract Introduction Sleep duration may associated with suicide attempts (SA) in patients with psychiatric disorders, but it remains uncertain whether interventions targeting sleep duration can effectively prevent SA in those people. This study was to evaluate whether adopting a normal sleep duration can prevent SA among patients with psychiatric disorders, and across specific diagnostic subgroups, using a target trial emulation based on observational data. Methods A target trial emulation was designed using the UK Biobank data. Eligible participants were patients with psychiatric disorders, diagnostic subcohorts for substance use disorders, depression, anxiety disorders and psychotic disorders were additionally defined. The intervention was adopting normal sleep duration (7-8 h/day), compared with abnormal (≤6 or ≥9 h/day). The outcome was SA, ascertained through linked hospital and mortality records. We applied inverse probability treatment weighting to balance confounders. Weighted Cox models estimated hazard ratios for SA in the main cohort and across diagnostic subtypes. Sensitivity analyses excluded individuals with a prior SA and separately assessed comparisons with short and long sleep duration. Results A total of 81 747 participants were included (49 838 in the intervention group and 31 909 in the control group), with SA rates of 1.20% and 2.00%, respectively. Adopting normal sleep duration at baseline was associated with a lower risk of SA (HR: 0.72, 95%CI: 0.65-0.81), with divergence emerging early in the risk curves. Sensitivity analyses yielded consistent findings. Results for substance use disorders (HR: 0.64, 95%CI: 0.52-0.78), depression (HR: 0.82, 95%CI: 0.72-0.94) and anxiety disorders (HR: 0.62, 95%CI: 0.50-0.78) aligned with the main analysis, whereas no significant protective association was observed in the psychotic disorders cohort (HR: 0.80, 95%CI: 0.50-1.27). Conclusion Adopting normal sleep duration confers a protective effect against SA in patients with psychiatric disorders. The magnitude of this benefit may vary by the severity and nature of the underlying psychiatric condition. These findings highlight sleep duration as a clinically meaningful and modifiable behavioral factor for SA prevention. Integrating targeted sleep-management strategies into routine psychiatric care may offer a feasible and actionable approach to prevent SA. Support (if any)