Abstract
BACKGROUND: The atherogenic risk factor profile in obese subjects is characterised by hypertension, reduced high density lipoprotein (HDL) cholesterol, increased low density lipoprotein (LDL) cholesterol and triglycerides, and insulin resistance. AIMS: To examine the amount of weight reduction required to improve the atherogenic profile. METHODS: Changes of systolic and diastolic blood pressure, HDL and LDL cholesterol, triglycerides, and insulin resistance, based on the HOMA model over a one year period were studied in obese children, who attended the intervention programme "Obeldicks". The children were divided into four groups according to the change in body mass index standard deviation score (SDS-BMI): group I, increase in SDS-BMI; group II, decrease in SDS-BMI <0.25; group III, decrease in SDS-BMI > or =0.25-<0.5; group IV, decrease in SDS-BMI > or =0.5. RESULTS: A total of 130 children (mean age 10.7 years, range 4-15; mean SDS-BMI 2.5, range 2.0-4.0) were studied. The four groups did not differ in age, gender, or degree of overweight (SDS-BMI). An increasing SDS-BMI (group I: n = 20) was followed by a significant increase in insulin resistance (HOMA). Systolic and diastolic blood pressure, LDL cholesterol, triglycerides, and insulin resistance (HOMA) decreased significantly while HDL cholesterol increased significantly in group IV (n = 37). LDL cholesterol also decreased significantly in group III (n = 40); there was no significant change of the other parameters in groups I, II, and III. CONCLUSION: Over a time period of one year increasing weight in obese children leads to an increase in insulin resistance. Weight loss is associated with an improvement in the atherogenic profile and in insulin resistance, but only if the SDS-BMI decreases by at least 0.5 over a one year period.