Dymanic assessment of respiratory function in patients with combination of COPD and type 2 diabetes mellitus. (Results of prospective study)

Chronic obstructive pulmonary disease (COPD) is often combined with type 2 diabetes mellitus (DM2), which worsens the course of the disease and worsens the prognosis. The effect of this comorbidity on the dynamics of respiratory function, especially static pulmonary volumes, has not been sufficiently studied. Objective. Dynamic assessment of lung respiratory function in patients with combined COPD and DM2. Materials and methods. The prospective study included 97 male patients with COPD. The main group consisted with COPD and DM2; the control group consisted 42 participants with isolated COPD. All patients underwent annual spirometry and body plethysmography, and the level of glycates hemoglobin (HbA1c) was assessed. The follow-up period was 4 years. Results. Initially, FEV1 and FVC were significantly lower in patients with comorbidity than in the control group (p<0.001). Over 4 years, a faster progression of obstructive and restrictive disorders was recorded in the main group: a decrease in FEV1 was −510 ml vs −380 ml in the control (p<0.001). the analysis of static lung volumes revealed a statistically significant increase in pulmonary hyperinflation. The indicators of intrathoracic gas volume (ITGV), residual volume (RV), total lung capacity (TLC) and the RV/TLC ratio in the group with DM2 were significantly higher at all stage of follow-up (p<0.001). an inverse correlation was established between the HbA1c level and FEV1 (r= −0.645) and FVC (r= −0.571), as well a direct relationship with hyperinflation indicators (p<0.001). Conclusion. The combination of COPD and DM2 a more severe phenotype of the disease, characterized by an accelerated decrease in respiratory function and progressive hyperinflation of the lungs. The revealed correlation with the level of HbA1c confirms the negative impact of carbohydrate metabolism disorders. Caful monitoring of the lung function, including body plethysmography, and strict glycemic control are recommended for patients with this comorbidity.