Military generation and its relationship to mortality in women veterans in the Women's Health Initiative

Purpose of the Study: Women' s military roles, exposures, and associated health outcomes have changed over time. However, mortality risk - within military generations or compared with non-Veteran women - has not been assessed. Using data from the Women' s Health Initiative (WHI), we examined all-cause and cause-specific mortality by Veteran status and military generation among older women. Design and Methods: WHI participants (3,719 Veterans; 141,802 non-Veterans), followed for a mean of 15.2 years, were categorized into pre-Vietnam or Vietnam/after generations based on their birth cohort. We used cox proportional hazards models to examine the association between Veteran status and mortality by generation. Results: After adjusting for sociodemographic characteristics and WHI study arm, all-cause mortality hazard rate ratios (HRs) for Veterans relative to non-Veterans were 1.16 (95% CI: 1.09-1.23) for pre-Vietnam and 1.16 (95% CI: 0.99-1.36) for Vietnam/after generations. With additional adjustment for health behaviors and risk factors, this excess mortality rate persisted for pre-Vietnam but attenuated for Vietnam/after generations. After further adjustment for medical morbidities, across both generations, Veterans and non-Veterans had similar all-cause mortality rates. Relative to non-Veterans, adjusting for sociodemographics and WHI study arm, pre-Vietnam generation Veterans had higher cancer, cardiovascular, and trauma-related morality rates; Vietnam/after generation Veterans had the highest trauma-related mortality rates (HR = 2.93, 1.64-5.23). Implications: Veterans' higher all-cause mortality rates were limited to the pre-Vietnam generation, consistent with diminution of the healthy soldier effect over the life course. Mechanisms underlying Vietnam/after generation Veteran trauma-related mortality should be elucidated. Efforts to modify salient health risk behaviors specific to each military generation are needed.