Altered association of plasmatic oxytocin with affective stress responses in alcohol use disorder

Oxytocin has been proposed to play a role in the development and maintenance of alcohol use disorder (AUD) through its interactions with stress pathways. Empirical evidence that indicates altered associations between endogenous oxytocin and stress reactivity in AUD is currently lacking. In this study, we investigated baseline plasmatic oxytocin concentrations of early-abstinent patients with AUD (N = 40) and matched healthy control participants (N = 37), who completed the Trier Social Stress Test (TSST) as well as a control task on two separate visits. We measured salivary cortisol and pulse rate as indicators of a physiological stress response, and anxiety ratings as an indicator of an affective stress response at multiple time points. Baseline oxytocin levels did not significantly differ between the groups. However, our results suggest an altered association of oxytocin and affective stress responses in participants with AUD: while participants with AUD showed a positive relationship between plasmatic oxytocin levels and stress-induced anxiety increase, the opposite relationship was found in control participants. We did not find evidence for an association of oxytocin with physiological stress responses. Assuming that affective stress responses mediate addiction-related behaviors like craving and relapse, our findings suggest that administering exogenous oxytocin might not be beneficial in treating AUD, at least during the early stages of abstinence.