Metabolic consequences of childhood obesity--a preliminary report

INTRODUCTION: Childhood obesity is increasing in Sri Lanka. Obesity related morbidity is mainly associated with the metabolic syndrome (MetS) and non-alcoholic steatohepatitis (NASH). Recent studies have shown these serious health consequences in obese children. OBJECTIVES: The objectives of our study were to document the presence of MetS and NASH in obese Sri Lankan children, to correlate the fat mass (FM) with the waist circumference (WC) and the body mass index (BMI), and to compare the association of the WC, BMI and the WHR (waist-hip ratio) with the metabolic derangements. METHOD: Children attending the Obesity Clinic at Lady Ridgeway Hospital, Colombo, from November 2004 to September 2005 were studied. The relevant sociodemographic data, anthropometric measurements and examination findings were documented. After a 12-hour overnight fast, blood was taken for estimation of lipid profile, serum insulin, liver enzymes and blood glucose. The oral glucose tolerance test (OGTT) was done in children over 5 years of age. Fatty infiltration of the liver was assessed by identifying specific features on ultrasonography and the degree of infiltration was given a score. We modified the International Diabetes Federation (IDF) 2004 guidelines to define MetS. NASH was defined as fatty infiltration of the liver associated with a raised serum ALT. RESULTS: Seventy children (40 boys) were studied. The mean (SD) age was 9.7 (2.5) and 9.3 (3.0) years for boys and girls respectively. Mean BMI was 25.9 in both groups. All patients had a WC > 98th percentile. MetS was found in 13 of the 63 (21%) children on whom all criteria were assessed. Sixty children had ultrasonography and NASH was seen in 11 (18%). The correlation of the percentage FM was greater with the BMI (r = 0.80; p < 0.001) than with the WC (r = 0.56; p < 0.001), but the WC was more significantly associated with the metabolic derangements than either BMI or WHR. CONCLUSIONS: Serious metabolic abnormalities are found in obese Sri Lankan children and the WC is a reliable indicator of these derangements.