Alcohol Use Disorder and Inflammatory Cytokines in a Population Sample of Young Adults

Abstract

Background: Alcohol abuse is followed by neuroadaptive brain changes, in addition to inducing changes in the immune system. The objective of this study was to investigate the peripheral levels of proinflammatory (IL-6, and TNF-α) and anti-inflammatory (IL-10) cytokines, as well the inflammatory balance in relation to alcohol use in subjects from a young population-based sample. Methods: This is a cross-sectional study nested in a population-based study of people aged 18–35 years, involving 629 participants. The CAGE questionnaire was used to evaluate Alcohol Use Disorder, and CAGE scores ≥ 2 were considered a positive screen for alcohol use disorder. Serum levels of IL-6, IL-10 and TNF-α were measured by ELISA using a commercial kit. Results: There was as a statistically significant increase in IL-6 (p ≤ 0.001) and statistically significant decrease in IL-10 (p=0.017) serum levels in the Alcohol Use Disorder group when compared with subjects that did not abuse alcohol and that a CAGE score <2. TNF-α levels were not significantly different. There was a statistically significant difference in IL-6/IL-10 (p ≤ 0.001). The median ratios were 0.28 (0.20 to 0.36) in the CAGE group with scores <2 and 0.70 (0.52 to 0.93) in the group with alcohol use disorder for the IL-6/IL-10. Conclusion: Our results suggest that cytokines, especially IL-6 and IL-10, are involved in the pathophysiology of abuse and dependence of alcohol, and could be candidate markers of alcohol use disorder.