Sex differences in spatial visualization and episodic memory as a function of alcohol consumption

Sex differences in visuospatial ability as well as episodic memory have been reliably demonstrated, irrespective of alcoholism. Studies in alcoholics have consistently documented cognitive deficits in visuospatial ability, problem solving and memory function. This cross-sectional, population-based study examined if sex differences in cognitive performance could be impacted by alcohol consumption.

Drinking data were collected from 2224 randomly sampled adults, aged between 35 and 85 years, who participated in the Betula study on memory, health and aging. Participants were classified into non-, light, moderate and heavy drinking subgroups based on sex-adjusted normative values. Cognitive tasks demonstrating clear sex differences, such as episodic memory tasks (favouring women) and spatial visualization tasks (favouring men), were conducted and performance was assessed by sex and the drinking group.

After controlling for age and education, overall analyses found expected sex differences in episodic memory and spatial visualization that were apparent across the entire population. When these sex differences were examined by drinking group, visuospatial performance favouring men disappeared for the moderate to heavy drinking groups, but higher performance by women on episodic memory tasks was consistent across all levels of alcohol consumption. Traditional biomarkers of increased alcohol consumption (GGT and MCV) correlated with the reported drinks/day.

These results lend support to the theory that moderate alcohol intake may be beneficial to cognitive function in women, but not necessarily in men.