Sub Clinical Impairment of Ventilatory Functions in Diabetes

Background: Respiratory disease is seldom attributed to diabetes mellitus (DM) directly. But, histopathology findings and abnormalpulmonary functions in various studies suggest that there is some sub clinical impairment in lung. This also affects the treatment of DM by insulin inhalation.Aim- To study the effect of exercise on ventilatory pulmonary function tests (VPFT) in diabetics (type II DM) to see the minimalearly deterioration, to evaluate their sub clinical impairment and the pattern of change.Material & methods- In this study VPFT are recorded in 30 patients suffering from type-II DM (with out complications) before, immediately after and 5 minutes after mild exercise and compared with that of normal healthy subjects as controls.Settings and design – Before and after exercise- VPFT comparison studies with controls (Non- Randomized).Statistical analysis- By standard statistical method using paired and unpaired‘t’ tests and ‘p’ values.Results- Values of FEV1/FVC (Forced Expiratory Volume in one second/Forced Vital Capacity) %, FEF (Forced Expiratory Flow) at 50% & 75% of vital capacities were significantly less in diabetics and lowered further after exercise. FEV1, FVC & MVV(Maximum Voluntary Ventilation) were comparable but failed to rise significantlyafter exercise contrary to that seen in healthy controls. FVC, FEV1/FVC%, FEF75% and MVV failed to recover significantly 5 minutes after exercise in diabetics.Conclusion - Spirometeric study of VPFT for various parameters reveal varying impairments, suggesting peripheral airway disease with predominantly obstructive pattern that precipitates/deteriorates further after exercise. Failure to recover indicates loss of elastic recoil, suggesting somerestriction.