Aims:  Limited studies on phase angle (PhA) and sarcopenia in continuous ambulatory peritoneal dialysis (CAPD) patients. We want to explore the association between PhA and sarcopenia and clarify its significance and value in diagnosing sarcopenia. Methods: We included 87 CAPD patients. We measured the PhA and body composition by bioelectrical impedance analysis. All patients had their handgrip strength (HGS) measured. Then, we divided patients into the sarcopenia (n=25) group and non-sarcopenia(n=62) group according to the sarcopenia diagnostic strategy formulated by the Asian Working Group for Sarcopenia. Results : Univariate analysis shows PhA is positively associated with HGS, skeletal muscle mass (SMM), and Upper arm muscle circumference (AMC). After adjustments for sex, age, diabetes, BMI, extracellular water ratio(E/T), extra water (OH), serum creatinine, total kt/v, and residual kt/v, PhA remains correlated to HGS and AMC, but not to SMM. In the multivariate logistic model, PhA is not correlated to sarcopenia. The AUROC of PhA for sarcopenia is 0.76(95% CI, 0.65-0.86, P<0.01, fig 3). The optimal cut-off value is identified as ≤5.25(sensitivity 74%, specificity 76%). Conclusion : This study illustrates that older age and higher total kt/v are risk factors for sarcopenia. PhA is positively associated with HGS and AMC but not with sarcopenia in CAPD patients. These results suggest that PhA can predict muscle mass and strength in CAPD patients, but its diagnosis value for sarcopenia needs more studies.

The authors have declared no competing interest.

YES-This study was funded by The government subsidizing the training program for outstanding clinical medical talents in 2021, study on nutrition evaluation and intervention of chronic kidney disease population- based on machine learning(103), Hebei Provincial Health Commission. It Provides funding for following up patients and finding papers .

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The Ethics Committee approved the study protocol of The Third Hospital of Hebei Medical University (number:20210931). All subjects signed an informed consent form.

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