Background: The association between stress and alcohol dependence has been well established. Abnormalities in stress reactivity and hypothalamic-pituitary-adrenal axis (HPA) function may be involved in the mechanistic connection between stress and the initiation, development, and/or maintenance of alcohol dependence. Posttraumatic stress disorder (PTSD) commonly co-occurs with alcohol dependence and is characterized by HPA axis abnormalities. This study investigated the relationship between subjective and neuroendocrine stress reactivity to the cold pressor task (CPT) and prospective alcohol use among individuals with alcohol dependence, with and without comorbid PTSD.
Methods: Participants were 63 individuals with (a) alcohol dependence only (n=35) or (b) comorbid alcohol dependence and PTSD (n=28). Participants completed the CPT, a widely used physical laboratory stressor. Subjective stress, craving, adrenocorticotrophin (ACTH), and cortisol were measured before, immediately after, and at 5, 30, 60, and 120 minutes after the CPT. Alcohol use during 1 month following testing was also assessed.
Results: For the alcohol-only group, change in craving immediately following the CPT and craving during the 120-minute recovery phase were predictive of follow-up alcohol use. For the alcohol/PTSD group, change in craving was not predictive of follow-up use. Baseline drinking was, however, predictive of followup alcohol use for the alcohol/PTSD group. For the alcohol-only group, a blunted ACTH response coupled with a higher change in craving following the CPT was associated with significantly greater frequency and intensity of drinking during the follow-up phase.
Conclusions: These preliminary findings demonstrate significant differences between the alcohol-only and the alcohol/PTSD group in predictors of relapse. For the alcohol-only group, reactivity to an acute laboratory stressor may be predictive of subsequent alcohol use. This was not true for the alcohol/PTSD group. Although preliminary, the findings may help shed light on the mechanistic relationship between stress reactivity and increased risk for alcohol relapse and dependence in individuals with and without other Axis I comorbidity.