Lung function in type 2 diabetes: the Normative Aging Study

Background: Cross-sectional studies have noted that subjects with diabetes have lower lung function than non-diabetic subjects. We conducted this analysis to determine whether diabetic subjects have different rates of lung function change compared with non-diabetic subjects. Methods: We conducted a nested case-control analysis in 352 men who developed diabetes and 352 non-diabetic subjects in a longitudinal observational study of aging in men. We assessed lung function among cases and controls at three time points: Time0, prior to meeting the definition of diabetes; Time1, the point when the definition of diabetes was met; and Time2, the most recent follow-up exam. Results: Cases had lower forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) at all time points, even with adjustment for age, height, weight, and smoking. In multiple linear regression models adjusting for relevant covariates, there were no differences in rates of FEV1 or FVC change over time between cases and controls. Conclusions: Men who are predisposed to develop diabetes have decreased lung function many years prior to the diagnosis, compared with men who do not developdiabetes. This decrement in lung function remains after the development of diabetes. We postulate that mechanisms involved in the insulin resistant state contribute to the diminished lung function observed in our subjects. (c) 2005 Elsevier Ltd. All rights reserved.