The role of phase angle in the diagnosis of presarcopenia in elderly patients with type 2 diabetes mellitus

The study of age-associated diseases is an integral component of modern medicine. In the conducted study, diagnostic phase angle limits for the detection of presarcopenia in patients with type 2 diabetes mellitus (T2DM) were determined. Early detection of sarcopenia in patients with T2DM helps to increase the duration and quality of their life.

BACKGROUND. Sarcopenia, like T2DM, not only is an age-associated disease, but is also recognized as a complication of T2DM. According to the results of studies by domestic scientists, phase angle (PA) parameters can be used for diagnostically significant decrease in muscle mass during bioempidansometry, but diagnostic limits for the diagnosis of presarcopenia are not presented. At the same time, the phase angle is an integral index of the processes occurring in the human body.

OBJECTIVE. To compare FS values depending on the presence of presarcopenia and to define diagnostic limits of FS for the diagnosis of presarcopenia in patients with T2DM.

MATERIALS AND METHODS. A one-stage single-centre cross-sectional study of patients over 60 years of age hospitalized in the endocrinology department of Buyanov State Clinical Hospital due to decompensation of T2DM was performed. During hospitalization, the SARC-F questionnaire was used to detect sarcopenia syndrome, patients with more than 4 points were included in the main stage of the study to detect sarcopenia according to the EWGSOP 2 consensus.

Statistical processing was performed using the SPSS Statistics 23 software package.

RESULTS. During the study period, 232 patients were examined, of whom 147 (63% of the total number of patients; 35 men (24%) and 112 women (76%); average age ― (70 ± 8) years) participated in the study; presarcopenia was detected in 87 people (59% of the study population). In patients with presarcopenia the mean FA was lower than in patients without signs of sarcopenia, the values were (7.05 ± 2.37)⁰ and (8.50 ± 1.59)⁰, respectively (p = 0.0001). The area under the ROC curve corresponding to the relationship between presarcopenia prognosis and phase angle was 0.714 ± 0.044 with 95 % CI: 0.627–0.800. The obtained model was statistically significant (p < 0.001). The threshold value of FA at the cut-off point was 6.61⁰. A high risk of presarcopenia was predicted at FA equal or lower than this value. The sensitivity and specificity of the method were 80.0 % and 62.1 %, respectively.

CONCLUSION. The study demonstrates that patients with presarcopenia have a prognostically significant decrease in FA, which makes it possible to diagnose sarcopenia in patients with T2DM at early stages, before the body's muscle reserves are exhausted, and to carry out its timely correction.