Factors Affecting Malnutrition in Continuous Ambulatory Peritoneal Dialysis Patients: A Cross-sectional Study

Kang, Ea Wha; Goo, Young Suck; Lee, Sang Cheol; Han, Seung Hyeok; Yoon, Soo Young; Choi, So Rae; Park, Hyeong Cheon; Kang, Shin Wook; Choi, Kyu Hun; Lee, Ho Young; Han, Dae Suk

Abstract

PURPOSE: Protein-calorie malnutrition is common in continuous ambulatory peritoneal dialysis (CAPD) patients and is associated with an increase in morbidity and mortality. This cross-sectional study was carried out to investigate prevalence of protein-calorie malnutrition in Korean CAPD patients. Other purposes were to ascertain relationship between various nutritional parameters and to evaluate factors independently associated with malnutrition in CAPD patients.
METHODS
Subjects were clinically stable 127 patients who have been on CAPD for more than 3 months. Nutritional status was assessed by subjective global assessment (SGA), biochemical, anthropometric, and urea kinetic parameters.
RESULTS
The mean age of the patients was 50.7+/-11.4 years with sex ratio (M : F) 1 : 1, and mean duration of dialysis was 67.3+/-39.7 months. Patients were divided into 3 groups according to SGA : group I (normal nutrition, n=75, 59.0%), group II (mild malnutrition, n=30, 23.6%) and group III (moderate to severe malnutrition, n=22, 17.4%). There were significant differences in age, CAPD duration, peritonitis rate and hospital-days per year between group I and group III. Among biochemical variables, serum creatinine, triglyceride, protein, albumin, prealbumin, IGF- 1, transferrin and leptin were significantly lower in group III compared to group I (p<0.05), and CRP, ferritin, and IL-6 were significantly higher in group III than group I. There were significant differences in serum albumin among all three groups. There were no differences in Kt/Vurea, nPNA and SCCr among three groups. However, there were significant differences in residual renal function (p<0.05) and PNA (p<0.05) between group I and group III. Among anthropometric variables, body weight, %IBW, BMI, %body fat mass, MAC, TSF, BSF, CAMA, and TBM were significantly lower in group III than the other two groups (p<0.05). But, there was no differences in exercise capacity and food intake among the three groups. To evaluate relationship between various parameters used for assessing malnutrition, we conducted Pearson's rank correlation test. Serum albumin (gamma=0.45), age (gamma=-0.29), %IBW (gamma=0.52), leptin (gamma=0.32), CRP (gamma=-0.24), TSF (gamma=0.45) and CAMA (gamma=0.41) significantly correlated with SGA. As a result of multiple regression analysis, albumin, leptin, and CRP were independent predictors of malnutrition (p<0.05).
CONCLUSION
About 40% of CAPD patients were malnourished according to SGA, and multiple regression analysis revealed that serum albumin, leptin and CRP were independent predictors of malnutrition. These results suggest that acute and chronic inflammatory response plays an important role in the development of protein-calorie malnutrition in CAPD patients with comparable food intake and dialysis dose.