Kidney function in obese adolescents with or without metabolic syndrome in a nationally-representative sample of pediatric population: First report from the Middle East and North Africa: The CASPIAN-III Study: A Case-Control Study

BACKGROUND: Obesity in accordance with metabolic syndrome (MetS) confronts populations at the higher risk of morbidity and mortality of chronic diseases including, chronic kidney diseases (CKD). The renal complication of obesity and MetS has been less debated in young adolescents. The objective of this study was to assess the kidney function in obese adolescents with or without MetS. MATERIALS AND METHODS: The data used in this study were collected as part of a national study entitled Childhood and Adolescence Surveillance and Prevention of Adult Non-communicable disease Study. The present study was conducted on a sub-sample of 113 obese adolescents (body mass index >95(th) percentile) aged between 10 years and 16 years selected by convenient sampling from the whole population studied. Anthropometric indexes and blood pressure were examined. A 12-h fasting serum was obtained for each participant to measure blood glucose, lipid profile, quantitative C-reactive protein (hs-CRP), Cystatin-c, urea, and creatinine. Fasting spot urine was collected to determine microalbumin and creatinine. Based on the study findings, participants were assigned into two groups with and without MetS. RESULTS: The mean of microalbuminuria was in similar ranges in two groups and while the mean glomerular filtration rate (GFR) calculated by Bokenkamp's, updated and combined Schwartz's formulas were significantly lower in MetS + obese group in comparison with obese group. The similar result was not achieved by Filler's formula. Among MetS components, waist circumference had a correlation with hs-CRP (P = 0.04; r = 0.15). GFR was calculated based on the Schwartz formula and Cystatin-c formulas had no significant correlation with any MetS components. CONCLUSION: Our findings suggest that MetS can increase the risk of kidney dysfunction in obese adolescents. More studies are suggested in this regard in the pediatric population.