Diabetic pneumopathy: A study of induced sputum and pulmonary function in patients with type 2 diabetes mellitus

Objective: To evaluate the cellularity, and albumin and interleukin (IL)-1 levels in induced sputum (IS), and to determine respiratory function parameters in patients with type 2 diabetes mellitus (DM2). Design: A cross-section study in type 2 diabetes mellitus. Participants: Patients with type 2 diabetes mellitus and healthy people. Methods: Patients in both groups had normal chest x-ray findings. Exclusion criteria for both groups were: the presence of current pulmonary disease or sequelae, smoking, respiratory atopy, or respiratory infection in the past 3 months. The study consisted of two sub-studies. In sub-study 1 (SS1), measurements of pulmonary volume and flow, and diffusion capacity for carbon monoxide (DLCO) were performed. In sub-study 2 (SS2), analysis of cellularity, albumin, and IL-1 in IS was performed. Results: In all, 60 patients (45 women, 75%) with DM2 with a mean age of 59.52 years (SD, 9.03) were included in SS1. The DM2 group included 8 patients with airway obstruction (13.33%) without reversibility with bronchodilators, and 9 with restrictive disease (15.00 %) (p = 0.026). The DLCO was reduced in 17 patients (28.33%) in the DM2 group. In the control group, all individuals had values within the reference intervals. Lymphocytosis was found in the IS of patients with DM2 (p = 0.028). The levels of sputum albumin showed no statistical difference between the two groups. Conclusion: Our findings indicate the presence of pulmonary impairment in DM2, characterized by changes in the respiratory function and a lymphocytosis in IS. Keywords: Diabetes mellitus type 2; Induced sputum; Lymphocytes.