Do daily fluctuations in inhibitory control predict alcohol consumption? An ecological momentary assessment study

RATIONALE: Deficient inhibitory control is predictive of increased alcohol consumption in the laboratory; however, little is known about this relationship in naturalistic, real-world settings. OBJECTIVES: In the present study, we implemented ecological momentary assessment methods to investigate the relationship between inhibitory control and alcohol consumption in the real world. METHODS: Heavy drinkers who were motivated to reduce their alcohol consumption (N = 100) were loaned a smartphone which administered a stop signal task twice per day at random intervals between 10 a.m. and 6 p.m. for 2 weeks. Each day, participants also recorded their planned and actual alcohol consumption and their subjective craving and mood. We hypothesised that day-to-day fluctuations in inhibitory control (stop signal reaction time) would predict alcohol consumption, over and above planned consumption and craving. RESULTS: Multilevel modelling demonstrated that daily alcohol consumption was predicted by planned consumption (β = .816; 95% CI .762–.870) and craving (β = .022; 95% CI .013–.031), but inhibitory control did not predict any additional variance in alcohol consumption. However, secondary analyses demonstrated that the magnitude of deterioration in inhibitory control across the day was a significant predictor of increased alcohol consumption on that day (β = .007; 95% CI .004–.011), after controlling for planned consumption and craving. CONCLUSIONS: These findings demonstrate that short-term fluctuations in inhibitory control predict alcohol consumption, which suggests that transient fluctuations in inhibition may be a risk factor for heavy drinking episodes. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s00213-018-4860-5) contains supplementary material, which is available to authorized users.