Combat Exposure and Risk for Suicidal Thoughts and Behaviors Among Military Personnel and Veterans: A Systematic Review and Meta-Analysis.

Due to seemingly mixed empirical results, questions persist about the possible role of deployments and combat exposure. We conducted a narrative review and meta-analysis of 22 published studies to integrate findings regarding the relationship of deployment-related predictors (i.e., deployment, deployment to a combat zone, combat experience, and exposure to specific combat events) with suicide-related outcomes (i.e., suicide ideation, attempt, and death). Across all predictors and outcomes, the combined effect was small and positive, r = .08 [0.04, 0.13], and marked by significant heterogeneity, I  = 99.9%, Q(21)=4880.16, p < .0001, corresponding to a 25% increased risk for suicide-related outcomes among those who have deployed. Studies examining the relationship between exposure to killing and atrocities (k = 5) showed the largest combined effect, r = .12 [0.08, 0.17], and less heterogeneity, I  = 84.4%, Q(4)=34.96, p < .0001, corresponding to a 43% increased risk for suicide-related outcomes among those exposed to killing or atrocity. Implications for theory, research, and clinical practice are discussed.