Biological stress indicators as risk markers for increased alcohol use following traumatic experiences

Alcohol misuse is a common sequela of traumatic event experiences causing considerable morbidity and mortality. Although biological stress indicators have been identified as useful risk markers for the development of trauma-related disorders, no such biological indicators exist for the risk of increased alcohol use after trauma exposure. This is the first study to prospectively investigate the predictive value of long-term cortisol levels and acute stress reactivity for the risk of increased alcohol use following traumatic events. Male soldiers were examined before and 12 months following deployment using a standardized diagnostic interview. We analyzed the moderating role of baseline hair cortisol concentrations (HCCs, n = 153) as well as baseline salivary cortisol and alpha-amylase stress reactivity in response to a laboratory stressor (n = 145) in the association between new-onset traumatic events (according to the DSM-IV A1 criterion) and subsequent daily alcohol use. No main effects of pre-traumatic HCC or salivary stress markers on subsequent change in alcohol use were observed. However, we found that with decreasing HCC, the number of new-onset traumatic events was more strongly associated with subsequent alcohol use independent from changes in posttraumatic stress disorder symptoms. No such relation was seen for the acute stress reactivity data. Taken together, this study provides first evidence suggesting that individual differences in long-term cortisol regulation are involved in the association between traumatic experiences and subsequent alcohol use. HCC may thus serve as a potential target in the early identification of individuals vulnerable for increased alcohol use following traumatic events.