Cortisol, DHEA sulphate, their ratio, and all-cause and cause-specific mortality in the Vietnam Experience Study

Objectives: The aim of the present analyses was to examine the association between cortisol, DHEA sulphate (DHEAS) and the cortisol: DHEAS ratio and mortality. Design: This was a prospective cohort analysis. Methods: Participants were 4255 Vietnam-era US army veterans. From military service files, telephone interviews and a medical examination, occupational, socio-demographic and health data were collected. Contemporary morning fasted cortisol and DHEAS concentrations were determined. Mortality was tracked over the subsequent 15 years. The outcomes were all-cause, cardiovascular disease, cancer, other medical mortality and external causes of death. Cox proportional hazard models were tested, initially with adjustment for age, and then with adjustment for a range of candidate confounders. Results: In general, cortisol concentrations did not show an association with all-cause or cause-specific mortality. However, in age-adjusted and fully adjusted analyses, DHEAS was negatively related to all-cause, all cancers and other medical mortality; high DHEAS concentrations were protective. The cortisol: DHEAS ratio was also associated with these outcomes in both age-adjusted and fully adjusted models; the higher the ratio, the greater the risk of death. Conclusions: DHEAS was negatively associated, and the ratio of cortisol to DHEAS was positively associated with all-cause, cancer and other medical cause mortality. Further experimental study is needed to elucidate the mechanisms involved in these relationships.