Alcohol consumption and diabetes risk in the Diabetes Prevention Program.
BACKGROUND
Moderate alcohol consumption is associated with a decreased risk of type 2 diabetes in the general population, but little is known about the effects in individuals at high risk of diabetes.


OBJECTIVE
The objectives were to determine associations between alcohol consumption and diabetes risk factors and whether alcohol consumption was a predictor of incident diabetes in individuals enrolled in the Diabetes Prevention Program (DPP).


METHODS
DPP participants (n = 3175) had impaired glucose tolerance (2-h glucose: 7.8-11.1 mmol/L), elevated fasting glucose (5.3-7.0 mmol/L), and a body mass index (in kg/m(2)) > or =24. Participants were randomly assigned to placebo, metformin, or lifestyle modification and were followed for a mean of 3.2 y. Alcohol intake was assessed at baseline and year 1 by using a semiquantitative food-frequency questionnaire. Diabetes was diagnosed by annual oral-glucose-tolerance testing and semiannual fasting plasma glucose measurement.


RESULTS
Participants who reported higher alcohol consumption tended to be male, older, white, and less obese and to have a higher calorie intake and a higher HDL-cholesterol concentration. Higher alcohol consumption was associated with lower insulin secretion at any level of insulin sensitivity. We found lower incidence rates of diabetes with higher alcohol consumption in the metformin (P < 0.01 for trend) and lifestyle modification (P = 0.02 for trend) groups, which remained significant after adjustment for multiple baseline covariates. No similar association was observed in the placebo group.


CONCLUSIONS
Despite overall low rates of alcohol consumption, there was a reduced risk of incident diabetes in those who reported modest daily alcohol intake and were assigned to metformin or lifestyle modification. Moderate daily alcohol intake is associated with lower insulin secretion-an effect that warrants further investigation. This trial was registered at clinicaltrials.gov as NCT00038727.
Crandall
Jill P
JP
Albert Einstein College of Medicine, Bronx, NY, USA. dppmail@biostat.bsc.gwu.edu
Polsky
Sarit
S
Howard
Andrea A
AA
Perreault
Leigh
L
Bray
George A
GA
Barrett-Connor
Elizabeth
E
Brown-Friday
Janet
J
Whittington
Tracy
T
Foo
Sandra
S
Ma
Yong
Y
Edelstein
Sharon L
SL
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000428:Alcohol Drinking; D008076:Cholesterol, HDL / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology / Q000517:prevention & control*; D002149:Energy Intake; D005260:Female; D018149:Glucose Intolerance / Q000188:drug therapy; D005951:Glucose Tolerance Test; D015438:Health Behavior; D006801:Humans; D006943:Hyperglycemia / Q000188:drug therapy; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D015994:Incidence; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D008019:Life Style; D008297:Male; D008687:Metformin / Q000627:therapeutic use*; D008875:Middle Aged; D009765:Obesity / Q000150:complications; D010919:Placebos / Q000627:therapeutic use; D012307:Risk Factors; D012737:Sex Factors
D008076:Cholesterol, HDL; D007004:Hypoglycemic Agents; D007328:Insulin; D010919:Placebos; D008687:Metformin