Evaluation of nutritional status and factors related to malnutrition in children on CAPD

The aim of this study was to investigate the nutritional status of children on continuous ambulatory peritoneal dialysis (CAPD) and to relate it to the dose of dialysis and serum levels of inflammatory cytokines and insulin-like growth factor-1 (IGF-1).

17 CAPD patients (8 girls, 9 boys; mean age 13.1 +/- 3.5 years, median 15 years) were included in the study. Anthropometric measurements and serum albumin levels were used in the evaluation of nutritional status. Serum interleukin (IL)-1beta, IL-6, tumor necrosis factor alpha, and IGF-1 levels were determined in all CAPD patients and in a healthy control group. Weekly Kt/V and creatinine clearance (CCr) were measured to determine adequacy of dialysis.

The mean dialysis period was 23.7 +/- 15.2 months (median 23 months). Anthropometric measurements and serum albumin level were as follows: height 130.2 +/- 15.6 cm, height standard deviation score (HtSDS) -4.2 +/- 2.4, body mass index (BMI) 16.3 +/- 1.6 kg/m2, body mass index standard deviation score (BMISDS) -0.8 +/- 0.9, triceps skinfold thickness (TST) 4.2 +/- 1.4 mm, midarm circumference (MAC) 16.21 +/- 2.3 cm, upper arm muscle area (AMA) 1799.1 +/- 535.7 mm2, upper arm fat area (AFA) 334.5 +/- 143 mm2, and serum albumin 3.1 +/- 0.7 g/dL. The BMI was above the fifth percentile in all patients; TST and MAC were below the fifth percentile in 14 patients (82.4%) and 10 patients (58.8%) respectively. The AMA was below the fifth percentile in 8 patients; however, the AFA was below the fifth percentile in all patients. Mean serum albumin level was under 3.5 g/dL in 70.5% of the children. We found significant positive correlations between BMI and Kt/V (r = 0.69, p < 0.01), CCr (r = 0.64, p < 0.05), and IL-6 (r = 0.61, p < 0.01). There was an inverse correlation between BMISDS and dialysis period (r = -0.58, p < 0.05); and between IL-6 and serum albumin (r = -0.49, p < 0.05). A significant positive correlation between BMISDS and serum IGF-1 level (r = 0.62, p < 0.01) was noted. We also found a significant positive correlation between serum IGF-1 level and both HtSDS (r = 0.57, p < 0.05) and TST (r = 0.52, p < 0.05). Significant positive correlations between AFA and CCr and IGF-1 were also noted (both r = 0.56, p < 0.05).

Although many factors may be responsible for malnutrition and growth retardation, we found that prolonged period of dialysis, inadequate dialysis, and low IGF-1 levels are the most important risk factors in CAPD patients.