All-cause mortality among United States military personnel: Findings from the Millennium Cohort Study, 2001–2021

Purpose

The goal of this study was to estimate all-cause mortality among Operations Enduring Freedom, Iraqi Freedom, and New Dawn era service members and veterans and to identify protective and risk factors for mortality.

Methods

Using 20 years of longitudinal data from the Millennium Cohort Study (2001–2021), sequential Cox proportional hazard models were conducted to examine demographic, military, and health-related characteristics associated with all-cause mortality among service members and veterans.

Results

Among 201,619 participants, 3806 (1.9 %) were deceased by the end of the observation period, with an age- and sex-adjusted incidence of 37.6 deaths per 100,000 person-years. Deployed service members had lower all-cause mortality risk than those who did not deploy. Personnel who experienced combat had higher mortality risk compared with those who did not in unadjusted models; this association was nonsignificant after accounting for health-related factors. Enlisted and Army personnel both had a higher mortality risk, while women and Hispanic individuals had a lower risk. Stressful life events, lower physical health related quality of life, problem drinking, and smoking were also associated with greater mortality risk.

Conclusion

These profiles may be useful for developing preventive education and intervention efforts in military and veteran populations to reduce premature mortality.