Alcohol consumption and cognitive performance: a Mendelian randomization study

Aims To use Mendelian randomization to assess whether alcohol intake was causally associated with cognitive function. Design Mendelian randomization using a genetic variant related to alcohol intake (ADH1B rs1229984) was used to obtain unbiased estimates of the association between alcohol intake and cognitive performance. Setting Europe. Participants More than 34 000 adults.Measurements Any versus no alcohol intake and units of intake in the previousweekwasmeasured by questionnaire. Cognitive functionwas assessed in terms of immediate and delayed word recall, verbal fluency and processing speed. Findings Having consumed any versus no alcohol was associated with higher scores by 0.17 standard deviations (SD) [95 % confidence interval (CI) = 0.15, 0.20] for imme-diate recall, 0.17 SD (95 % CI = 0.14, 0.19) for delayed recall, 0.17 SD (95 % CI = 0.14, 0.19) for verbal fluency an