Cigarette smoking, environmental tobacco smoke exposure and insulin sensitivity - The Insulin Resistance Atherosclerosis Study

PURPOSE: To investigate whether active smoking and/or exposure to environme ntal tobacco smoke (ETS) is associated with insulin sensitivity. METHODS: Insulin sensitivity and tobacco use history were measured in 1481 participants in the Insulin Resistance Atherosclerosis Study (IRAS). IRAS i s a large mulitcenter epidemiologic study designed to explore the cross sec tional relationships among insulin resistance, cardiovascular disease risk factors and behaviors, and disease in African-American, Hispanic, and non-H ispanic white men and women, aged 40-69 years, selected to represent a broa d range of glucose tolerance. Multiple linear regression models and linear contrasts were employed to describe the association between smoking history , as assessed via structured interview, and insulin sensitivity, as assesse d by an insulin modified frequently sampled intravenous glucose tolerance t est (FSIGT) with minimal model analysis. RESULTS: Active smoking was not associated with insulin sensitivity.. Expos ure to ETS was associated with lower insulin sensitivity. Specifically, for all participants combined, levels of S-1 were lower, indicating reduced in sulin sensitivity, for those exposed to ETS when compared to those who were not exposed (p = 0.019). This association persisted for female participant s (p = 0.013) and exhibited the same trend for males but failed to achieve statistical significance (p = 0.264). CONCLUSIONS: Our study did not reveal an association between active smoking and insulin sensitivity, as has been shown previously. The association bet ween ETS exposure and insulin sensitivity is a puzzling finding which deser ves further investigation in the longitudinal data from IRAS as well as in other populations. Published by Elsevier Science Inc.