ABSTRACT
BACKGROUND: Survey research found poorer baseline immune fitness for self-reported hangover-sensitive drinkers compared to hangover-resistant drinkers. However, up to now a limited number of clinical studies revealed mixed results regarding the relationship between the concentrations of biomarkers of systemic inflammation in blood or saliva with hangover severity, and could not differentiate between hangover-sensitive drinkers and hangover-resistant drinkers. The aim of this study was to assess immune fitness and saliva biomarkers of systemic inflammation at multiple timepoints following an alcohol day and alcohol-free control day. METHODS: The study had a semi-naturalistic design. In the evening before the test days, participants were not supervised. They could drink ad libitum drinking on the alcohol test day and refrained from drinking alcohol on the control day. Activities and behaviors on the alcohol and control day were reported the follow morning. On both test days, from 09:30 to 15:30, hourly assessments of immune fitness (single-item scale) and overall hangover severity (single-item scale) were made and saliva samples were collected for biomarker assessments. RESULTS: N = 14 hangover-resistant drinkers and n = 15 hangover-sensitive drinkers participated in the study. The amount of alcohol consumed on the alcohol day did not significantly differ between the hangover-resistant group (mean (SD) of 13.5 (7.9) alcoholic drinks) and the hangover-sensitive group (mean (SD) of 12.4 (4.4) alcoholic drinks). All hangover-sensitive drinkers reported having a hangover following the alcohol day (overall hangover severity score 6.1 (on a 0-10 scale) at 09:30, gradually decreasing to 3.3 at 15:30), whereas the hangover-resistant drinkers reported no hangover. On the control day, immune fitness of the hangover-sensitive group was significantly poorer than the hangover-resistant group. On the alcohol day, both groups showed a significant reduction in immune fitness. The effect was evident throughout the day, but significantly more pronounced in the hangover-sensitive group than the hangover-resistant group. No significant differences between the groups were found at any time point on the two test days for saliva concentrations of Interleukin (IL)-1ß, IL-6, IL-8, and tumor necrosis factor (TNF)-α. CONCLUSIONS: Whereas hangover-sensitive drinkers reported a hangover following an alcohol day and hangover-resistant drinkers did not, both groups reported significantly reduced immune fitness throughout the day. However, the reduction in immune fitness among hangover-sensitive drinkers was significantly more pronounced in comparison to the hangover-resistant group.
