Longitudinal courses of suicidal ideation in US military veterans: a 7-year population-based, prospective cohort study

Background Varied longitudinal courses of suicidal ideation (SI) may be linked to unique sets of risk and protective factors. Method A national probability sample of 2291 U.S. veterans was followed over four assessments spanning 7 years to examine how a broad range of baseline risk and protective factors predict varying courses of SI. Results Most veterans (82.6%) denied SI at baseline and all follow-ups, while 8.7% had new onset SI, 5.4% chronic SI, and 3.3% remitted SI. Compared to the no-SI group, chronic SI was associated with childhood trauma, baseline major depressive and/or posttraumatic stress disorder (MDD/PTSD), physical health difficulties, and recent traumatic stressors. Remitted veterans had the highest risk of a prior suicide attempt (SA) compared to no-SI [relative risk ratio (RRR) = 3.31] and chronic SI groups (RRR = 4.65); and high rates of MDD/PTSD (RRR = 7.62). New onset SI was associated with recent stressors and physical health difficulties. All symptomatic SI groups reported decrements in protective factors, specifically, social connectedness, trait curiosity/exploration, and purpose in life. Conclusion Nearly one-in-five veterans reported SI over a 7-year period, most of whom evidenced new onset or remitted SI courses. Chronic and remitted SI may represent particularly high-risk SI courses; the former was associated with higher rates of prospective SA, and psychiatric and physical distress, and the latter with increased likelihood of prior SA, and isolation from social and mental health supports. Physical disability, MDD/PTSD, and recent stressors may be important precipitating or maintaining factors of SI, while social connectedness may be a key target for suicide prevention efforts.