Phase angle as an independent predictor of sarcopenia and glycemic control in older adults with type 2 diabetes: a cross-sectional observational study.

Objectives: The global rise in type 2 diabetes mellitus (T2DM) poses challenges, particularly with the increasing burden of sarcopenia and poor glycemic control. Phase angle (PhA) is a promising biomarker for early detection and management of these conditions. This study aimed to evaluate PhA as an independent predictor of sarcopenia and glycemic control.

Methods: This cross-sectional study included older adults with T2DM hospitalized for diabetes education between April 2021 and March 2023. Measurements included PhA, muscle mass, body fat mass, grip strength, knee extension strength, physical function (Short Physical Performance Battery and 6-min walk distance), and glycemic control (fasting blood glucose and hemoglobin A1c [HbA1c]). Sarcopenia was defined as low muscle mass and physical function. Analyses included Pearson correlations, receiver operating characteristic curve analysis, and multivariate logistic regression.

Results: PhA was moderately correlated with muscle mass (r = 0.42, p < 0.001), grip strength (r = 0.43, p < 0.001), and body mass index (r = 0.27, p = 0.001), and inversely correlated with HbA1c (r = - 0.34, p < 0.001) and age (r = - 0.26, p = 0.003). PhA showed a strong predictive ability for sarcopenia (AUC = 0.83, 95% CI: 0.76-0.90, p < 0.001). Logistic regression indicated PhA as an independent predictor of sarcopenia (OR = 0.105, 95% CI: 0.031-0.353, p < 0.001) and glycemic control (OR = 0.380, 95% CI: 0.201-0.719, p = 0.003).

Conclusions: PhA is a non-invasive, practical tool for predicting sarcopenia and monitoring glycemic control. Routine integration of PhA could identify high-risk patients and guide interventions. Future research should validate its application in diverse settings.

Supplementary information: The online version contains supplementary material available at 10.1007/s40200-025-01590-z.