Individual and Cumulative Stress and Cardiovascular Health Among Contemporary U.S. Service Members: The Millennium Cohort Study

INTRODUCTION: Military service members face unique occupational stressors (e.g., combat deployment) that are compounded by additional life stressors (e.g., adverse childhood experiences [ACEs], financial problems). As stress has been shown to be associated with the increased risk of cardiovascular disease (CVD) in civilian populations, the present study examined the associations between stress exposure and cardiovascular health (CVH) among a contemporary military population. MATERIALS AND METHODS: Using a cross-sectional design, survey data from 40,525 service members (71% men, 58% non-Hispanic White, 94% <35 years old) enrolled in the Millennium Cohort Study from 2020 to 2021 were analyzed to estimate associations between stress exposure and CVH. Individual stressors, including self-reported combat severity, bullying, hazing, discrimination, sexual harassment, ACEs, and stressful life events (SLEs) (e.g., divorce, financial problems), were z-score transformed and combined to form a cumulative stress measure. An index CVH score was adapted from the American Heart Association's Life's Essential 8 measure (i.e., self-reported sedentary time <8 hours/day, sleeping 7-9 hours/day, no daily fast-food intake, not currently smoking, healthy body mass index [18.5-24.9 kg/m2], no diabetes, no high cholesterol, and no hypertension). Linear regression models examining the relationship between individual stressors and cumulative stress with CVH were adjusted for sociodemographic, military, and behavioral factors. RESULTS: Higher cumulative stress scores were associated with lower CVH scores among service members in our sample. When examining individual stressors, SLEs were most strongly related with poorer CVH, followed by ACEs, bullying, and combat severity. CONCLUSION: Cumulative stress may have a significant impact on the CVH of service members. Moreover, SLEs (e.g., divorce, financial problems, moving) that occur outside of their military duties may have a substantial impact on force readiness and retention. A consideration of specific stressors and screening for multiple stressors during routine health care visits can provide an opportunity for early CVD prevention among military populations.