Moderate consumption of alcohol, especially red wine, in addition to a healthy diet may modestly reduce cardiometabolic risk among patients with well-controlled diabetes, according to published in the Annals of Internal Medicine.
Iris Shai, RD, PhD, professor at Ben-Gurion University of the Negev in Beer Sheva, Israel, and colleagues conducted a randomized controlled trial of alcohol-abstaining adults aged 40 to 75 years with well-controlled type 2 diabetes (n = 224) enrolled in the single-phase, 2-year CASCADE trial from June 2010 to May 2012 at two centers in Israel. They measured lipid variables (HDL, apolipoprotein A-I and total cholesterol-to-HDL ratio) and glycemic control (fasting plasma glucose level and homeostasis model assessment of insulin resistance [HOMA-IR] score), along with BP and liver biomarkers. Participants also responded to electronic questionnaires at baseline and 6 and 24 months on demographics, lifestyle patterns, medication use and symptoms and quality of life.
Along with adherence to a Mediterranean diet without caloric restrictions, participants were randomly assigned to consume 150 mL red wine (14.2% ethanol), white wine (13.3% ethanol) or mineral water at dinner. Participants’ adherence to beverage assignment was assessed by tracking their returned bottles, along with responses to questionnaires about alcohol intake and self-reported adherence rankings.
Follow-up at 1 year and 2 years indicated a significant 9.8% increase in HDL levels in the red wine group compared with the water group (mean difference, 2 mg/dL; 95% CI, 1.6-2.2). ApoA-I was also significant increased among those assigned to consume red wine compared with water (mean difference, 0.03 g/L; 95% CI, 0-0.06). Total cholesterol-to-HDL ratio decreased by 0.27 (95% CI, –0.52 to –0.01) for the red-wine group compared with the water group at 2 years. White wine consumption was not associated with alterations in lipid levels.
Compared with water, white wine consumption was associated with decreased fasting plasma glucose (mean, 17.2 mg/dL; 95% CI, –28.9 to –5.5) and HOMA-IR score (mean, 1.2; 95% CI, –2.1 to –0.2). However, the researchers noted that participants who metabolized ethanol slowly benefited from consumption of either wine type with regard to glycemic control parameters, including fasting glucose, HbA1c and HOMA-IR.
No differences between the groups were identified in BP, adiposity, liver function, drug therapy, symptoms or quality of life, with the exception of sleep quality, which improved in both wine groups compared with the water group (P = .04). Red wine consumption was also associated with a reduction in the number of components of the metabolic syndrome (mean, 0.34; 95% CI, –0.68 to –0.001) compared with the water group, Shai and colleagues wrote.
“Only the slow alcohol-metabolizers who drank wine achieved an improvement in blood glucose control, while fast alcohol metabolizers — with much faster blood ethanol clearance — did not benefit from the ethanol’s glucose-control effect,” Shai told Cardiology Today.
Shai recommended future studies should include a more extensive examination of morbidity and mortality rates. – by Trish Shea, MA
Disclosure: The study was supported by funding from the European Foundation for the Study of Diabetes. Shai reports no relevant financial disclosures.