The relationship between alcohol consumption, cognitive performance, and daily functioning in an urban sample of older black Americans.

OBJECTIVE

To report on moderate alcohol consumption and measurements of cognitive function and activities of daily living in an older, urban, community-dwelling sample of black Americans.

DESIGN

As part of a community prevalence study of dementia, information on alcohol consumption and cognitive performance was collected on 2040 randomly selected black subjects living in Indianapolis.

MEASUREMENTS

From questions in the screening interview, alcohol consumption was grouped into four categories: lifetime abstainers, regular drinkers less than 4 drinks per week, 4 to 10 drinks per week, and more than 10 drinks per week. Current and past drinkers were analyzed separately. Three measurements were used: (1) a total cognitive score; (2) the delayed recall score from the East Boston Memory Test; (3) a score for daily functioning based upon information from the informant. Multiple regression models were fitted with drinking variables as the major predictor, including covariates of age, gender, education, history of stroke, hypertension, being treated for depression, and a family history of dementia.

MAIN RESULTS

In all analyses, there was a very consistent pattern for both current and past drinkers. There was a small but significant dose effect of drinking for the drinkers, with subjects in the heaviest drinking category scoring poorest, i.e., lowest scores in cognitive tests and highest scores in scales of daily functioning indicating more impairment. The scores of abstainers were worse than those of subjects in the lightest drinking category. The pattern of scores for cognitive performance and daily functioning was similar between current and past drinkers. These patterns remained the same even after potential confounders were included.

CONCLUSIONS

Previous research on effects of alcohol on health indices have suggested a J-shaped relationship between amounts of alcohol consumption and measurements of heart disease, stroke, and mortality rates. Our study provides some support for the concept of a similar J-shaped relationship between cognitive performance and alcohol consumption, but the differences between drinking categories were modest and the clinical significance of these findings uncertain.