Examining the link between prior suicidality and subsequent suicidal ideation among high-risk US military service members

Background Research is needed to identify the factors that explain the link between prior and future suicidality. This study evaluated possible mediators of the relationship between: (1) the severity of prior suicidality and (2) suicidal ideation severity at 3-month follow-up among a sample of high-risk military personnel. Methods US military service members referred to or seeking care for suicide risk (N = 624) completed self-report psychiatric domain measures and a clinician interview assessing prior suicidality severity at baseline. Three months later, participants completed a self-report measure of suicidal ideation severity. Three separate percentile bootstrap mediation models were used to examine psychiatric factors (i.e. alcohol abuse, anxiety sensitivity, hopelessness, insomnia, posttraumatic stress symptoms, suicidal ideation, and thwarted belongingness) as parallel mediators of the relationship between prior suicidality severity (specifically, suicidal ideation, suicide attempt, and overall suicidality - i.e. ideation/attempt severity combined) at baseline and suicidal ideation severity at follow-up. Results Hopelessness, specifically, and the total effect of all mediators, each significantly accounted for the relationship between prior suicidality severity and subsequent ideation severity across models. In the models with attempt severity and overall suicidality severity as predictors, thwarted belongingness was also a significant mediator. Conclusions Hopelessness, thwarted belongingness, and overall severity of psychiatric indices may explain the relationship between prior suicidality severity and future suicidal ideation severity among service members at elevated suicide risk. Research is needed to replicate these findings and examine other possible mediators.