Sargeant, Lincoln A. ; Khaw, K. T. ; Bingham, S. ; Day, N. E. ; Luben, R. N. ; Oakes, S. ; Welch, A. ; Wareham, N. J.
Author Affiliation, Ana.
Tropical Metabolism Research Unit
Cigarette smoking and glycaemia: The EPIC-Norfolk Study. European Prospective Investigation into Cancer
International Journal of Epidemiology
Date of Publication
Previous prospective studies have suggested that cigarette smoking may be associated with an increased risk of type 2 diabetes, but the possibility of confounding, particularly by dietary factors has not been fully examined. Conducted a cross-sectional analysis of the association between cigarette smoking and HbA(1C), a marker of long- term glucose homeostasis in 2704 men and 3385 women, aged 45--74 years who were recruited to a population-based study of diet and chronic disease. Twelve per cent of men and 11% of women reported being current smokers. Mean HbA(1C) was lowest in never smokers, intermediate in former smokers and highest in current smokers. There was a dose-response relationship between HbA(1C) levels and number of cigarettes smoked per day and a positive association with total smoking exposure as measured by pack-years. The unadjusted increase in HbA(1C) for 20 pack-years of smoking was 0.12% (95% CI : 0.09--0.16) in men and 0.12% (95% CI : 0.08--0.17) in women. After adjustment for possible confounders including dietary variables, the values were 0.08% (95% CI : 0.04--0.12) and 0.07% (95% CI : 0.02--0.12) for men and women, respectively. Mean HbA(1C) was inversely related to time since quitting smoking in men. These results add support to the hypothesis that smoking has long-term effects on glucose homeostasis, an association that cannot be explained by confounding by dietary factors as measured in this study.....