Comparing Objective Measures of Sleep Disturbance and Sleep Related Impairments as Proximal Risk Indicators of Suicidal Intent and Non‐Suicidal Self‐Injury

Background Non‐suicidal self‐injury (NSSI) and suicidal ideation (SI) are prevalent public health concerns among college students. Poor sleep quality and its consequences are a risk factor for NSSI and SI in this population. Unfortunately, limited research measures the impact of sleep related impairment (SRI) on NSSI/SI, little research compares the relative criterion validity of objective versus SRI measurement for NSSI/SI, and there is limited research measuring NSSI behaviors as a primary outcome. Methods This study examined the relationship between passively captured Consensus Sleep Diary indices (i.e., actigraphy), SRI, SI, and frequency of NSSI in a sample of N = 132 college‐students reporting past‐month NSSI/SI. Participants wore actigraphy wristbands during the 28‐day daily ambulatory phase and completed self‐report assessments each day ( k = 3726 observations). Results Multilevel mixed effects models failed to find significant relationships between actigraphy‐derived sleep quality indices, same‐day SI and NSSI frequency, and next‐day SI and NSSI frequency. Significant relationships between SRI, same‐day SI, and same‐day NSSI frequency emerged. Discussion Results suggest worsening SRI may be an important signal of worsening SI and NSSI frequency. Implications for assessment and monitoring of SRI for college students at risk for NSSI and suicide are discussed.