Daily and Cumulative Sleep Duration as Predictors of Suicidal Desire and Intent: An Ecological Momentary Assessment Study

Objective: Shorter sleep duration has been linked to increased suicidal ideation (SI). However, limited research has examined the relationship between nightly sleep duration and short-term fluctuations in suicide risk, as well as the potential clinical utility of leveraging indices of recent (ie, past 3 days) patterns of sleep duration as a marker of acute suicide risk. This study examined associations between nightly and cumulative sleep duration and suicidal desire and intent utilizing ecological momentary assessment (EMA) in a high-risk sample of community-based adults. Methods: A sample of 237 community-based adults with severe SI provided daily indices of self-reported sleep duration and ratings of suicidal desire and intent 6 times per day for 14 consecutive days of EMA monitoring. Data collection took place between February and May 2019. Results: Between-person nightly sleep duration and cumulative sleep duration were negatively associated with suicidal desire (Bs = −3.48 and −4.78) and intent (Bs = −1.96 and −2.46). At the within-person level, nightly sleep duration was negatively related to suicidal desire (Bs = −0.51 and −0.47) and intent. Within-person cumulative sleep duration, on the other hand, was unrelated to both suicidal desire and intent (Bs = −0.26 and −0.09). Conclusion: Our findings highlight the clinical utility of examining individual differences in sleep duration as a marker for suicide-related outcomes, as well as deviations from one’s typical nightly sleep as a potential acute predictor of suicide-related outcomes, in addition to information about recent duration over one or more nights of sleep. Limitations and future directions are discussed.