Impact of body mass index on survival in patients undergoing peritoneal dialysis: Analysis of data from the Insan Memorial End-Stage Renal Disease Registry of Korea (1985-2014).

Abstract

BackgroundSignificant increases in the prevalence of obesity have been observed among patients with peritoneal dialysis (PD). The impact of body mass index (BMI) on survival remains unknown in Korean PD patients.MethodsAmong data of 80,674 patients on PD acquired from the Insan Memorial ESRD Registry database for the years 1985 to 2014, 6,071 cases were analyzed. Subjects were classified by baseline BMI; < 21.19 kg/m2 (quartile 1, n = 1,518), 21.19 to 23.18 kg/m2 (quartile 2, reference; n = 1,453), 23.19 to 25.71 kg/m2 (quartile 3, n = 1,583), and > 25.71 kg/m2 (quartile 4, n = 1,517).ResultsMean age was 65.8 years, and baseline BMI was 23.57 kg/m2. Numbers of male and diabetic patients were 3,492 (57.5%) and 2,192 (36.1%), respectively. Among 6,071 cases, 2,229 (36.7%) all-cause deaths occurred. As a whole, Kaplan–Meier survival curves according to BMI quartiles was significantly different (P = 0.001). All-cause mortality was significantly higher in quartile 4 than in the reference (hazard ratio [HR] = 1.154, 95% confidence interval [CI], 1.025–1.300; P = 0.018). There was no statistical difference in all-cause mortality among BMI quartiles in diabetic patients on PD. In non-diabetic patients, all-cause mortality of quartiles 1 and 3 was not different from the reference, but the HR was 1.176 times higher in quartile 4 (95% CI, 1.024–1.350; P = 0.022).ConclusionBaseline BMI > 25.71 kg/m2 seems to be an important risk factor for all-cause mortality in Korean PD patients.