Search

OBJECTIVE Moderate alcohol consumption is associated with a reduced risk of type 2 diabetes. This reduced risk might be explained by improved insulin sensitivity or improved glycemic status, but results of intervention studies on this relation are inconsistent. The purpose of this study was to conduct a systematic review and meta-analysis of intervention studies investigating the effect of alcohol consumption on insulin sensitivity and glycemic status. RESEARCH DESIGN AND METHODS PubMed and Embase were searched up to August 2014. Intervention studies on the effect of alcohol consumption on biological markers of insulin sensitivity or glycemic status of at least 2 weeks' duration were included. Investigators extracted data on study characteristics, outcome measures, and methodological quality. RESULTS Fourteen intervention studies were included in a meta-analysis of six glycemic end points. Alcohol consumption did not influence estimated insulin sensitivity (standardized mean difference [SMD] 0.08 [-0.09 to 0.24]) or fasting glucose (SMD 0.07 [20.11 to 0.24]) but reduced HbA1c (SMD -0.62 [-1.01 to -0.23]) and fasting insulin concentrations (SMD -0.19 [-0.35 to -0.02]) compared with the control condition. Alcohol consumption among women reduced fasting insulin (SMD -0.23 [-0.41 to -0.04]) and tended to improve insulin sensitivity (SMD 0.16 [-0.04 to 0.37]) but not among men. Results were similar after excluding studies with high alcohol dosages (>40 g/day) and were not influenced by dosage and duration of the intervention. CONCLUSIONS Although the studies had small sample sizes and were of short duration, the current evidence suggests that moderate alcohol consumption may decrease fasting insulin and HbA1c concentrations among nondiabetic subjects. Alcohol consumption might improve insulin sensitivity among women but did not do so overall. [ABSTRACT FROM AUTHOR]

OBJECTIVE -- The purpose of this study was to investigate whether adiponectin concentrations and biomarkers of inflammation, endothelial dysfunction, and insulin resistance mediate the association between alcohol consumption and diabetes. RESEARCH DESIGN AND METHODS -- In a nested case-control study of 705 women with incident diabetes and 787 matched control subjects, we examined the adjusted relationship between baseline alcohol consumption and risk of diabetes before and after adjustment for markers of inflammation/endothelial dysfunction (C-reactive protein, vascular cell adhesion molecule-1, intercellular adhesion molecule-1, E-selectin, tumor necrosis factor-α receptor 2, and interleukin-6), fasting insulin, and adiponectin concentrations. RESULTS -- Alcohol consumption was associated with a decreased risk of diabetes (odds ratio per 12.5 g/day increment in alcohol use 0.58; 95% CI 0.49-0.69; P < 0.001). Adjustment for BMI attenuated the association by 25%. None of the markers of inflammation or fasting insulin appeared to account for >2% of the observed relationship. Without adjustment for BMI, these biomarkers individually explained slightly more of the association, but <10% in all cases. Adiponectin accounted for 25% in a fully adjusted model and for 29% without adjustment for BMI. CONCLUSIONS -- In this population of women, alcohol consumption was inversely associated with risk of type 2 diabetes. Adiponectin appeared to be a mediator of this association, but circulating biomarkers of inflammation, endothelial dysfunction, and fasting insulin did not explain this association. These results suggest that further research is needed into the potentially mediating roles of other biomarkers affected by alcohol consumption. [ABSTRACT FROM AUTHOR]

OBJECTIVE -- This study aimed to investigate the relation between alcohol consumption and type 2 diabetes among older women. RESEARCH DESIGN AND METHODS -- Between 1993 and 1997, 16,330 women aged 49-70 years and free from diabetes were enrolled in one of the Dutch Prospect-EPIC (European Prospective Study Into Cancer and Nutrition) cohorts and followed for 6.2 years (range 0.1-10.1). At enrollment, women filled in questionnaires and blood samples were collected. RESULTS -- During follow-up, 760 cases of type 2 diabetes were documented. A linear inverse association (P = 0.007) between alcohol consumption and type 2 diabetes risk was observed, adjusting for potential confounders. Compared with abstainers, the hazard ratio for type 2 diabetes was 0.86 (95% CI 0.66-1.12) for women consuming 5-30 g alcohol per week, 0.66 (0.48-0.91) for 30-70 g per week, 0.91 (0.67-1.24) for 70-1.40 g per week, 0.64 (0.44-0.93) for 140-210 g per week, and 0.69 (0.47-1.02) for >21.0 g alcohol per week. Beverage type did not influence this association. Lifetime alcohol consumption was associated with type 2 diabetes in a U-shaped fashion. CONCLUSIONS -- Our findings support the evidence of a decreased risk of type 2 diabetes with moderate alcohol consumption and expand this to a population of older women. [ABSTRACT FROM AUTHOR]

Objective: This meta-analysis was undertaken to obtain insight regarding the shape and strength of the relationship between alcohol consumption and the risk of type 2 diabetes, the effects of adjustment for confounders, and the effect of modification by type 2 diabetes definition, sex, and BMI.Research Design and Methods: The 15 original prospective cohort studies that were included comprise 11,959 incident cases of type 2 diabetes in 369,862 individuals who, on average, were followed for 12 years.Results: After pooling the data, a U-shaped relationship was found. Compared with nonconsumers, the relative risk (RR) for type 2 diabetes in those who consumed /=48 g/day) was equal to that in nonconsumers (1.04 [0.84-1.29]). In general, nonsignificant trends for larger RR reduction associated with moderate alcohol consumption were observed for women compared with men, for crude compared with multivariate-adjusted analyses, and for studies that used self-reports instead of testing for type 2 diabetes definition. No differences in RR reductions were found between individuals with low or high BMI.Conclusions: The present evidence from observational studies suggests an approximately 30% reduced risk of type 2 diabetes in moderate alcohol consumers, whereas no risk reduction is observed in consumers of >/=48 g/day. [ABSTRACT FROM AUTHOR]

Objective: Epidemiological studies suggest that moderate alcohol consumers have enhanced insulin sensitivity and a reduced risk of type 2 diabetes. Adiponectin, an adipocyte-derived plasma protein, has been found to be negatively associated with adiposity and positively associated with insulin sensitivity. Moderate alcohol consumption may increase adiponectin, which in turn causes a decrease of tumor necrosis factor (TNF)-alpha. A decreased TNF-alpha level may consequently increase insulin sensitivity.Research Design and Methods: To test this hypothesis, we performed a randomized crossover partially diet-controlled study. A total of 23 healthy middle-aged male subjects consumed daily four glasses of whisky (40 g ethanol) or tap water with dinner during two successive periods of 17 days.Results: Moderate alcohol consumption increased plasma adiponectin level (11%; P = 0.0002) but did not affect plasma TNF-alpha level. An increase in insulin sensitivity index was observed in an insulin-resistant subgroup (21%; P = 0.11), which positively correlated with the relative alcohol-induced increase in plasma adiponectin level (r = 0.73, P = 0.02).Conclusions: The experimental results are in agreement with observational data. Moderate alcohol consumption improved insulin sensitivity in relatively insulin-resistant middle-aged men, an effect that may be mediated through alcohol-induced increases in adiponectin. [ABSTRACT FROM AUTHOR]

Objective: Moderate alcohol consumption is associated with a reduced risk of type 2 diabetes. This reduced risk might be explained by improved insulin sensitivity or improved glycemic status, but results of intervention studies on this relation are inconsistent. The purpose of this study was to conduct a systematic review and meta-analysis of intervention studies investigating the effect of alcohol consumption on insulin sensitivity and glycemic status., Research Design and Methods: PubMed and Embase were searched up to August 2014. Intervention studies on the effect of alcohol consumption on biological markers of insulin sensitivity or glycemic status of at least 2 weeks' duration were included. Investigators extracted data on study characteristics, outcome measures, and methodological quality., Results: Fourteen intervention studies were included in a meta-analysis of six glycemic end points. Alcohol consumption did not influence estimated insulin sensitivity (standardized mean difference [SMD] 0.08 [-0.09 to 0.24]) or fasting glucose (SMD 0.07 [-0.11 to 0.24]) but reduced HbA1c (SMD -0.62 [-1.01 to -0.23]) and fasting insulin concentrations (SMD -0.19 [-0.35 to -0.02]) compared with the control condition. Alcohol consumption among women reduced fasting insulin (SMD -0.23 [-0.41 to -0.04]) and tended to improve insulin sensitivity (SMD 0.16 [-0.04 to 0.37]) but not among men. Results were similar after excluding studies with high alcohol dosages (>40 g/day) and were not influenced by dosage and duration of the intervention., Conclusions: Although the studies had small sample sizes and were of short duration, the current evidence suggests that moderate alcohol consumption may decrease fasting insulin and HbA1c concentrations among nondiabetic subjects. Alcohol consumption might improve insulin sensitivity among women but did not do so overall., (© 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.)