Pulmonary function in non-insulin-dependent diabetes mellitus

Background: In type I diabetes mellitus, lung function has been investigate d in several clinical studies, but there are few data concerning pulmonary function abnormalities in patients with non-insulin-dependent diabetes mell itus (NIDDM). Objectives: The aim of this study was to assess the presence of pulmonary function abnormalities in patients with NIDDM and to verify th e possible associations between diabetic renal microangiopathy, retinopathy and diabetes control. Method and Patients: Thirty patients with NIDDM were collected and divided into two similar groups: subjects with retinopathy a nd/or diabetic glomerulopathy (group 1, n = 15) and patients without any co mplications (group 2, n = 15). 17 were males and 13 females, aged from 45 t o 81 years. They had had diabetes for 3-23 years and were studied at the Di vision of Internal Medicine, with an outpatient service for diabetic patien ts. All patients were non-smokers. The presence of diabetic glomerulopathy was determined by measuring the 24-hour protein excretion rate using the ne phelometric method. The presence of retinopathy was determined by using oph thalmoscopy. Glycosylated hemoglobin was measured as an indicator of glycem ic control. We performed a global spirometry and measured pulmonary diffusi on capacity by the single-breath method corrected by alveolar volume. Resul ts: We found a significant reduction in lung diffusion capacity for carbon monoxide (DLCO) in the group of patients with other signs of diabetic micro angiopathy (p < 0.005) and a significative correlation between DLCO and the grade of albumin uria (r = -0.83, p < 0.001). Conclusions: Pulmonary funct ion abnormalities, in particular a reduction in diffusion capacity, are com mon in patients with NIDDM and signs of diabetic microangiopathy. A possibl e explanation is related to an impaired pulmonary microvasculature and alve olar epithelial basal lamina. Copyright (C) 2001 S. Karger AG, Basel.