Little is known about the relationship between alcohol consumption and glycemic control among people with diabetes, state the authors of a recent study. The investigators carried out a follow-up survey in 1994-97 among 38,564 adult diabetes patients who were members of the Kaiser Permanente Northern California plan to evaluate the association between alcohol consumption and glycemic control. Self-reported alcohol consumption, and hemoglobin A1C (A1C), were assessed within 1 year of survey date. Linear regression of A1C by alcohol consumption was performed, adjusted for sociodemographic variables, clinical variables, and diabetes disease severity. Least squares means estimates were derived.
Results showed that in multivariate-adjusted models, mean A1C values were 8.88 (lifetime abstainers), 8.79 (former drinkers), 8.90 (<0.1 drink/day), 8.71 (0.10.9 drink/day), 8.51 (11.9 drinks/day), 8.39 (22.9 drinks/day), and 8.47 (≥3 drinks/day). Alcohol consumption was linearly (p<0.001) and inversely (p=0.001) associated with A1C among diabetes patients. The authors conclude that alcohol consumption is inversely associated with glycemic control among diabetes patients. This supports current clinical guidelines for moderate levels of alcohol consumption among diabetes patients. As glycemic control affects incidence of complications of diabetes, the lower A1C levels associated with moderate alcohol consumption may translate into lower risk for complications.
R Curtis Ellison comments: You may recall that a recent clinical trial (Shai et al, Glycemic effects of moderate alcohol intake among patients with type 2 diabetes: A multi-center, randomized clinical intervention trial. Diabetes Care 2007;30:3011-3016) showed that previously non-drinking diabetics advised to begin to consume a glass of wine daily had evidence over one year of lower fasting blood glucose levels than did subjects randomly assigned to continue abstinence. The present analysis based on more than 38,000 diabetics from the large Kaiser Permanente group shows that alcohol intake is associated with significantly lower levels of Hb A1C, a marker for prevailing level of blood glucose. A lower A1C level is a good indicator of better control of diabetes. The authors state that earlier research has shown that a 1% reduction in A1C is associated with a 21% reduction of the risk of any diabetes-related endpoint and a 37% reduction in the risk of microvascular complications. Thus, the magnitude of decrease in A1C levels associated with alcohol use (from 8.88 among lifetime abstainers to 8.39 for subjects reporting 2-2.9 drinks/day) may be an important factor in the reduction of cardiovascular disease among diabetics who are moderate drinkers.
Source: Ahmed AT, Karter AJ, Warton EM, Doan JU, Weisner CM. The relationship between alcohol consumption and glycemic control among patients with diabetes: The Kaiser Permanente Northern California Diabetes Registry. J Gen Intern Med 2008;23:275282