Cross-sectional association between total level and type of alcohol consumption and glycosylated haemoglobin level: the EPIC-Norfolk Study

Objective: To investigate the association between total level and type of alcohol consumed and glycaemia. Design: Cross-sectional study. Setting: The EPIC-Norfolk Study, a population-based cohort study of diet and chronic disease. Subjects and methods: Non-diabetic men (n = 2842) and women (n = 3572), aged 40-78 y. Alcohol intake was assessed by self-reported questionnaire, and glycaemia measured by glycosylated haemoglobin (HbA(1c)). Results: Ten percent of men and 18% of women reported drinking no alcohol. Among drinkers, median alcohol intake was 8 units/week for men and 3 units/week for women. In analyses stratified by sex and adjusted for age, total energy intake, education, fruit and vegetable intake, smoking, family history of diabetes, physical activity, body mass index and waist:hip ratio, alcohol intake was inversely associated with HbA(1c) in men and women, although the association was stronger in women. A I unit/week increase in alcohol intake was associated with 0.0049% (s.e. = 0.00223; P-value = 0.028) and 0.017% (s.e. = 0.00343; P-value < 0.001) reduction in HbA(1c) in men and women respectively. In similar multivariate analyses, wine intake was inversely associated with HbA(1c) in men, and wine, spirits and beer intake were inversely associated with HbA(1c) in women. When also adjusted for total alcohol intake, only the association between wine intake and HbA(1c) in men remained significant. Conclusion: Alcohol intake was associated with lower HbA(1c) level, an association not explained by confounding. The distinction between type of alcohol consumed was particularly important in men. Sponsorship: NJW is an MRC Clinician Scientist Fellow.