Peripheral immune system suppression in early abstinent alcohol-dependent individuals: Links to stress and cue-related craving

Background: Peripheral immune system cytokines may play an integral role in the underlying sensitized stress response and alcohol craving during early alcohol withdrawal. To date, the nature of these immune changes during early abstinence have not been examined. Methods: A total of 39 early abstinent, treatment-seeking, alcohol-dependent individuals and 46 socially drinking controls were exposed to three guided imageries: stress, alcohol cue and neutral. These were presented randomly across consecutive days. Plasma measures of tumor necrosis factor alpha (TNF alpha), tumor necrosis factor receptor 1 (TNFR1), interleukin-6 (IL-6), and interleukin-10 (IL-10), were collected at baseline, immediately after imagery and at various recovery time-points. Ratings of alcohol craving, negative mood and anxiety were also obtained at the same time-points. Results: The alcohol group demonstrated decreased basal IL-10 compared with controls particularly following exposure to alcohol cue. They also showed a dampened TNF and TNFR1 response to stress and cue, respectively, and a generalized suppression of IL-6. In the alcohol group, these immune system adaptations occurred alongside significant elevations in anxiety, negative mood and alcohol craving. Conclusions: Findings demonstrate that broad immunosuppression is still observed in alcohol-dependent individuals after 3 weeks of abstinence and may be linked to motivation for alcohol.