The Association between Alcohol Consumption and Diabetes Risk is Independent of Dietary Pattern

Abstract

The ability to interpret epidemiologic relations of diet and disease risk is limited due to potential residual confounding by correlated dietary components. Assessing dietary patterns by factor analysis or partial least squares may overcome this limitation. To examine confounding by dietary pattern as well as standard risk factors and selected nutrients, the longitudinal association of alcohol consumption with 7‐year risk of type 2 diabetes mellitus (T2DM) was analyzed by Cox‐proportional hazard model in 2,879 healthy adults enrolled in Framingham Offspring Study. After adjusting for standard risk factors, consumers of ≥9.0 drink/week had a significantly lower risk of T2DM compared to abstainers (hazard ratio [HR]: 0.47; 95% confidence interval [CI]: 0.27, 0.81). Adjusting for selected nutrients little impacted the HR, whereas adjusting for dietary pattern variables by factor analysis significantly shifted the HR away from null (HR: 0.33, 95% CI: 0.17, 0.64) by 40.0% (95% CI: 16.8, 36.4%, P=0.002). Dietary pattern variables by partial least squares showed the similar results. Therefore, the observed inverse association, consistent with past studies, was confounded by dietary patterns, which was not corrected by adjusting for individual nutrients. The data suggest alcohol intake, and not dietary patterns associated with alcohol intake, is responsible for the observed inverse association with T2DM risk.Grant Funding SourceU.S. Department of Agriculture, Agricultural Research Service (No. 58‐1950‐7‐707)