Sex differences in binge drinking-related higher morning cortisol levels and in prospective association with future alcohol intake.

Aims: Peripheral cortisol represents one biological measure of the hypothalamic-pituitary-adrenal (HPA) axis, a significant component of the stress system, which is altered by chronic alcohol consumption. However, whether heavy alcohol use affects the HPA axis differentially between the sexes and whether basal cortisol levels are a biomarker of prospective alcohol intake is unknown.

Methods: We recruited light moderate (LM) and binge-heavy (BH) drinkers of alcohol (n = 118). Repeated fasting morning cortisol levels were studied over a 2-hour period to assess basal levels while participants underwent a neuroimaging scan.

Results: Significantly higher average cortisol levels in BH compared to LM groups across four timepoints were observed (P < .018). Overall sex differences were observed with women showing higher initial cortisol levels at the first timepoint with a blunted decrease over the morning relative to men (P < .003). Average morning cortisol differentially predicted prospective future 30-day daily reports of alcohol consumption by sex and group, such that LM males had a positive significant relationship and BH males had a negative non-significant relationship between cortisol and drinking.

Conclusions: Findings indicate that morning plasma cortisol is upregulated in the BH vs. LM group. Although females had higher initial morning cortisol levels, BH males showed a dysregulated negative relationship between stress and binge drinking in contrast to the LM group. Future work should further investigate the role of cortisol and other stress hormones as biomarkers of problematic drinking behaviors in men and women.