The Relation between Obesity and Glomerular Filtration Rate in Children and Adolescents

Jung, Youngsu; Kim, Dongwoon; Lim, Inseok

Abstract

PURPOSE
The prevalence of obesity in children and adolescents has been rising rapidly in Korea because of changes of diet and lifestyle. As with adults, obesity in children and adolescents can cause diabetes mellitus, hyperlipidemia, cardiovascular diseases and renal diseases. The aim of the present study is to examine the relation of obesity, glomerular filtration rate (GFR) and serum cystatin C concentration in children and adolescents. METHODS: Data of 115 children and adolescents aged between 6 years and 20 years without clinical evidence of renal diseases were included in the study. From May 2004 to December 2004, blood samples were collected from children and adolescents who were seen at the Department of Pediatrics at Chungang University Yongsan Hospital. Obesity degrees and body mass indices (BMI) were measured, and GFRs were estimated from Schwartz's formula. Serum cystatin C was measured by particle enhanced nephelometric immunoassay using Behring Nephelometer II. RESULTS: GFRs were significantly different between the obese group (BMI > 95 percentile, 145.79+/-23.10 mL/min) and the non-obese group (BMI < 95 percentile, 134.61+/-26.19 mL/min) divided by BMI (P=0.031). GFRs were not significantly different between the obese group (obesity degree > 120 percent, 144.29+/-23.08 mL/min) and the non-obese group (obesity degree < 120 percent, 134.54+/-26.57 mL/ min) divided by obesity degree (P=0.051), but were significantly different between severe obese group (obesity degree > 150 percent, 155.55+/-20.40 mL/min) and the non-obese group (P=0.004). GFRs were correlated positively with BMI (r2=0.037, P=0.039), but were not correlated significantly with obesity degree (r2=0.030, P=0.066). Serum cystatin C concentrations were not significantly different between the obese group and the non-obese group, divided by BMI as well as by obesity degree (P> 0.05). CONCLUSION: Obesity may lead to an alteration of renal hemodynamics such as hyperfiltration, appropriate control and management for obesity is necessary.