Some, but not all, observational studies have suggested that moderate levels of alcohol intake may be associated with improved cognitive function and reduced risk of cognitive decline and dementia. The authors of this 1996-2002 study used data from the Women's Health Initiative Memory Study of postmenopausal combination hormone therapy to assess cross-sectional and prospective associations of self-reported alcohol intake with cognitive function. Across 39 US academic medical centers, 4,461 community-dwelling women aged 65-79 years were followed an average of 4.2 years with annual Modified Mini-Mental State Examinations and standardized protocols for detecting mild cognitive impairment and probable dementia. Compared with no intake, intake of > or =1 drink per day was associated with higher baseline Modified Mini-Mental State Examination scores (p < 0.001) and a covariate-adjusted odds ratio of 0.40 (95% confidence interval: 0.28, 0.99) for significant declines in cognitive function. Associations with incident probable dementia and mild cognitive impairment were of similar magnitude but were not statistically significant after covariate adjustment. Associations with intakes of