The acute effects of alcohol on state rumination in the laboratory

Abstract

Rationale: Rumination is a repetitive, negative, self-focused thinking style associated with various forms of psychopathology. Recent studies suggest that rumination increases craving for alcohol and predicts harmful drinking and alcohol-related problems. However, the acute effects of alcohol on rumination have not been previously studied. It is proposed that alcohol may reduce ruminative thinking through decreasing negative mood.

Objectives: In the present study, we aimed to test the previously unexplored effects of acute alcohol consumption on rumination in a hazardous drinking population.

Methods: We conducted a randomised placebo-controlled laboratory study to examine the effect of low (0.4 g kg^-1) and high doses (0.8 g kg^-1) of alcohol on state rumination compared to placebo. Participants completed a rumination induction task prior to receiving drinks. We then measured state rumination and mood at repeated time points; 30 min, 60 min and 90 min post-drinks consumption.

Results: We found a significant decrease in state rumination in the low-dose alcohol group compared to placebo at 30 min post-alcohol consumption, but no difference was observed between the high-dose alcohol and placebo groups. Mediation analysis provided evidence for an indirect effect of alcohol on state rumination through concurrent changes in negative mood.

Conclusions: These findings suggest that acute alcohol consumption can regulate negative mood and concurrently rumination, providing preliminary evidence for the role of rumination in alcohol use disorders. Rumination may be a treatment target in alcohol use disorders.

Keywords: Alcohol use disorders; Depression; Negative affect; Rumination.

Fig. 1

Study procedures with approximate timings

Fig. 2

Mean BRAC (mg l⁻¹) across time of testing and alcohol administration group. There were significant (*p < 0.05) group differences in BRAC at all time points except at baseline. Error bars represent standard error of the mean. Thirty-one participants contributed to placebo group, 30 to low-dose alcohol group and 29 to high-dose alcohol group

Fig. 3

Mean state rumination about an unresolved problem over time and groups (low- and high-dose alcohol conditions collapsed together). There was a significant difference in state rumination between the placebo and the low-dose alcohol group at 30 min post-alcohol administration (*p < 0.05). Error bars represent standard error of the mean. 31 participants contributed to placebo group, 30 to low-dose alcohol group and 29 to high-dose alcohol group

Fig. 4

Mean state rumination measured using BSRI total scores over time and groups. Time*Condition interaction was not statistically significant. Error bars represent standard error of the mean. Respectively, 30 and 29 participants contributed data to low-dose and high-dose alcohol groups, and 31 contributed data to placebo group

Fig. 5

Mediation model demonstrating the indirect effect of alcohol dose on rumination by change in negative affect ratings. Significant effects are denoted by an asterisk