Abstract
Background: Pulmonary function is an independent risk factor for mortality in diabetes mellitus. Impaired pulmonary function, especially decreased alveolar gas exchange, can occur in cases with type 2 diabetes mellitus. Pulmonary function parameters such as forced expiratory volume at the first second (FEV1), forced vital capacity (FVC), FEV1/FVC, peak expiratory flow rate (PEFR), and FEF25–75% have significant changes in diabetic cases than healthy individuals.

Aims and Objectives: This study was designed to evaluate the pulmonary functions in type 2 diabetic cases and its correlation with body mass index (BMI) and glycemic control.

Materials and Methods: A total of 100 type 2 diabetic cases and 100 age-and sex-matched control subjects between 31 and 60 years were recruited. A 2 ml blood was collected to estimate blood glucose levels and hemoglobin A1c (HbA1c). Spirometer was used to measure the various lung function parameters like forced vital capacity (FVC), forced expiratory volume at first second (FEV1), peak expiratory flow rate (PEFR), FEV1/FVC and FEF25-75%.

Results: The mean difference of age, height, weight, and BMI was statistically not significant (P > 0.05). The mean FEV1, FVC, PEFR, and FEF25–75% were significantly lesser in type 2 diabetic cases than control subjects. The mean FVC, FEV1, FEF25–75%, and PEFR were low in cases with HbA1c <7 compared to the cases with HbA1c >7. The mean differences between pulmonary function tests were statistically not significant. There was a negative correlation between FVC, FEV1, and HbA1c levels.

Conclusion: The pulmonary functions were reduced in type 2 diabetes cases. It is necessary to undergo pulmonary function testing periodically in diabetic cases. Regular respiratory workouts help to strengthen respiratory muscles and firm glycemic control can improve the pulmonary function in type 2 diabetic cases.

Key words: Type 2 Diabetes Mellitus; Forced Vital Capacity; Forced Expiratory Volume at the First Second; Peak Expiratory Flow Rate