Abstract
RATIONALE & OBJECTIVE: Bioimpedance spectroscopy is a convenient method to measure lean tissue mass (LTM), which is commonly taken as the skeletal muscle mass, in peritoneal dialysis (PD) patients. We investigated the prognostic significance of LTM as the percentage of body weight (%LTM) and as the marker of sarcopenia in incident PD patients. STUDY DESIGN: A retrospective review of a prospective cohort. SETTING & PARTICIPANTS: 349 incident PD patients in a single center. PREDICTOR: Baseline %LTM. OUTCOMES: Patient survival, technique survival, peritonitis-free survival, peritonitis rate, hospitalization rate, and the duration of hospitalization. ANALYTICAL APPROACH: Time-to-event survival analyses; linear regression for hospitalization. RESULTS: The 5-year patient survival rates were 50.2%, 55.3%, 61.0%, and 72.6% for patients with %LTM quartiles I-IV, respectively (log-rank test; P = 0.02). Multivariable Cox regression analysis confirmed that baseline %LTM was associated with patient survival (adjusted HR, 0.982; 95% CI, 0.966-0.999; P = 0.04). Baseline %LTM was also associated with peritonitis-free survival (adjusted HR, 0.983; 95% CI, 0.968-0.998; P = 0.031), but not technique survival. %LTM was also significantly and inversely associated with the hospitalization rate (P = 0.002) and the duration of hospitalization (P = 0.02). Yet, %LTM was unrelated to the 5-year technique survival (P = 0.29) and the peritonitis rate (P = 0.15). The number of hospital admissions was 2.72, 2.39, 2.36, and 1.67 per year of follow-up for quartiles I-IV of baseline %LTM (Jonckheere-Terpstra test; P = 0.002), and the duration of hospital stay was 23.31, 20.84, 22.27, and 13.96 d/y, respectively (P = 0.02). LIMITATIONS: Observational study with baseline measures only. CONCLUSIONS: Baseline %LTM as measured using bioimpedance spectroscopy is associated with patient survival, peritonitis-free survival, the number of hospital admissions, and the duration of hospital stay in incident PD patients.