Alcohol consumption and cognitive decline in early old age

Objective: To examine the association between alcohol consumption in midlife and subsequent cognitive decline. Methods: Data are from 5,054 men and 2,099 women from the Whitehall II cohort study with a mean age of 56 years (range 44-69 years) at first cognitive assessment. Alcohol consumption was assessed 3 times in the 10 years preceding the first cognitive assessment (1997-1999). Cognitive tests were repeated in 2002-2004 and 2007-2009. The cognitive test battery included 4 tests assessing memory and executive function; a global cognitive score summarized performances across these tests. Linear mixed models were used to assess the association between alcohol consumption and cognitive decline, expressed as z scores (mean 5 0, SD 5 1). Results: In men, there were no differences in cognitive decline among alcohol abstainers, quitters, and light or moderate alcohol drinkers (,20 g/d). However, alcohol consumption $36 g/d was associated with faster decline in all cognitive domains compared with consumption between 0.1 and 19.9 g/d: mean difference (95% confidence interval) in 10-year decline in the global cognitive score520.10 (20.16, 20.04), executive function 520.06 (20.12, 0.00), and memory520.16 (20.26, 20.05). In women, compared with those drinking 0.1 to 9.9 g/d of alcohol, 10-year abstainers showed faster decline in the global cognitive score (20.21 [20.37, 20.04]) and executive function (20.17 [20.32, 20.01]). Conclusions: Excessive alcohol consumption in men ($36 g/d) was associated with faster cognitive decline compared with light to moderate alcohol consumption.