Electrical activity of expiratory muscles in type 2 diabetes mellitus

Abstract

Aim. To study the functional state of the expiratory muscles in patients with type 2 diabetes mellitus on the basis of changes in their electrical activity when using a functional test with a static expiratory effort. Materials and methods. 47 patients with type 2 diabetes mellitus and 40 patients without disorders of carbohydrate metabolism were examined. To study the electrical activity of the expiratory muscles, surface electromyography (EMG) of the external oblique abdominal muscle (OAM), rectus abdominis muscle (RAM), and internal intercostal muscles (IIM) was performed using a functional test with a static expiratory effort. Results. When performing a functional test with a static expiratory effort in both groups, a decrease in the frequency and an increase in the amplitude of EMG was observed, however, in patients with type 2 diabetes mellitus, these changes were less pronounced. There were also differences in the dynamics of changes in EMG indicators. In patients with type 2 diabetes mellitus, the decrease in the frequency of EMG OAM began from 10 seconds of the test, IIM – from 15 seconds, in the comparison group – from 5 and 10 seconds, respectively. The OAM EMG amplitude in the main group did not change significantly, in the comparison group it increased from 5 seconds of expiratory effort. At the 10th second of the test, the amplitude index of the EMG OAM in patients with type 2 diabetes mellitus was 10.4% lower (p=0.027) than in the comparison group, and at the 15th second – by 10.5% (p=0.033). Conclusion: The change in the electrical activity of the expiratory muscles in patients with type 2 diabetes mellitus is due to the slowed down dynamics of the frequency-amplitude characteristics of the EMG OAM, uncompensated IIM fatigue, as well as lower values of the OAM EMG amplitude when performing a functional exercise test with a static expiratory effort.