Relation of cigarette smoking, alcohol use, and coffee consumption to glycated hemoglobin in Japanese men and women

Abstract

Aims To investigate the relation of cigarette smoking, alcohol use, and coffee and green tea consumption to glycated hemoglobin (HbA 1c) concentrations. Methods Study subjects were 11,002 Japanese men and women aged 49–76 years in Fukuoka City who participated in the baseline survey of a cohort study on lifestyle-related diseases. Those with current or past treatment for diabetes mellitus were excluded. Multivariate-adjusted geometric means of HbA 1c and odds ratios of elevated HbA 1c (>5.8%) were obtained by analysis of covariance and logistic regression analysis, respectively. Results Cigarette smoking showed a strong, positive association with HbA 1c in men, but not in women. In men, adjusted odds ratio of elevated HbA 1c was 1.83 (95% CI 1.25–2.69) for those smoking 20 cigarettes/day or more versus never-smokers. HbA 1c concentrations were progressively lower with increasing levels of alcohol intake in both men and women. The adjusted odds ratios of elevated HbA 1c for the highest alcohol consumption versus never consumption were 0.62 (95% CI 0.43–0.93) in men and 0.94 (95% CI 0.58–1.52) in women. Coffee consumption showed a suggestive inverse association with HbA 1c concentrations in women only, while green tea was not related to HbA 1c in either men or women. Conclusions The present findings add to evidence that cigarette smoking confers deterioration in glucose metabolism and that alcohol intake is protective to glucose intolerance. Further studies are needed on coffee and HbA 1c concentrations.