Alcohol consumption and incident diabetes: The Atherosclerosis Risk in Communities (ARIC) study.

Aims/hypothesis: The aim of this study was to evaluate the prospective association between baseline and 9 year change in alcohol consumption and long-term risk of diabetes and whether these associations might be modified by sex and/or BMI.
Methods: We conducted a prospective analysis of 12,042 Atherosclerosis Risk in Communities (ARIC) study participants without prevalent diabetes (55% women, 78% white, mean age 54 years). Alcohol consumption was assessed at visit 1 (1987-1989) and visit 4 (1996-1998). We used Cox models to estimate hazard ratios for diabetes risk by baseline drinking categories and change in alcohol consumption, stratified by sex and obesity status.
Results: During a median follow-up of 21 years, there were 3795 incident cases of diabetes. Among women, consuming 8-14 drinks/week was associated with a significantly lower risk of diabetes (HR 0.75, 95% CI 0.58, 0.96) compared with current drinkers consuming ≤1 drink/week. Among men, consuming 8-14 drinks/week was associated with a borderline significant lower risk of diabetes (HR 0.84, 95% CI 0.70, 1.00) and consuming >14 drinks/week was associated with a significantly lower risk of diabetes (HR 0.81, 95% CI 0.67, 0.97) (p _interaction  < 0.01 for sex). For both sexes, among current drinkers, there was a significant decreasing trend in diabetes risk as the alcohol consumption increased. The association was modified by BMI (p _interaction  = 0.042 for women, p _interaction  < 0.001 for men). In women, the inverse association was only seen among overweight and obese participants. In men, the inverse association was more pronounced among obese participants. On average, drinking status did not change substantially over the 9 year period. For men with alcohol intake ≥7 drinks/week at baseline, decreasing alcohol intake was associated with higher risk of diabetes (HR per daily drink decrease 1.12, 95% CI 1.02, 1.23).
Conclusions/interpretation: In this community-based population, there was an inverse association between alcohol consumption and diabetes risk. The amount of the alcohol consumption associated with lower risk was different in women and men, and the association was more pronounced among participants with higher BMI.