Background: Domestic and international wars continue to be pervasive in the 21st century. This study summarizes the effects of war-related stress on all-cause mortality using meta-analyses and meta-regressions.
Methods: A keyword search was performed, supplemented by extensive iterative hand-searches for observational studies of war-related stress and mortality. Two hundred and twenty mortality risk estimates from 30 studies were extracted, providing data on more than 9 million persons.
Results: The mean hazard ratio (HR) was 1.05 [95% confidence interval (CI) 0.98-1.13] among HRs adjusted for age and additional covariates. The mean effect for men was 1.14 (CI 1.00-1.31), and for women it was 0.92 (CI 0.66-1.28). No differences were found for various follow-up durations or for various types of war stress. Neither civilians nor military personnel had an elevated mortality risk. Those exposed to a combat zone during the Vietnam War had a slightly higher chance of death (HR 1.11; 95% CI 1.00-1.23).
Conclusions: The results show that, over all, exposure to war-stress did not increase the risk of death when studies were well controlled. Effects were small when found. This lack of substantial effect may be the result of selection processes, developed resiliency and/or institutional support.