Prevalence and correlates of obesity in insulin dependent diabetic patients

The prevalence of obesity, according to sex and pubertal stage, and the correlations between obesity and metabolic data were investigated in 286 diabetic patients (164 boys, 122 girls) with mean (SD) age 15.3 (3.2) years and mean (SD) duration of diabetes 7.5 (4.1) years. Prevalence of obesity according to the body mass index (BMI) criteria was 6.3%. Girls were more often obese than boys but the prevalence approached statistical significance only for the BMI criteria, at 9.8% v 3.7% (chi 2 = 3.5; p = 0.06); obesity was independent of pubertal stage. Distribution of BMI values of diabetic girls was skewed towards the high centiles of the INSERM tables: < 25th centile, 8.6%; 25th-50th centile, 17.3%; 50th-75th centile, 25.9%; > 75th centile, 48.2% (chi 2 = 19.17, p < 0.0005). BMI values of diabetic boys were homogeneously distributed. Age, duration of diabetes, insulin requirement, daily number of insulin injections, and metabolic control (HbA1c) were comparable in obese and non-obese diabetic patients. Moreover metabolic control and insulin requirements were comparable between diabetic patients with BMI above and below the 50th centile of the INSERM tables after matching for sex. In conclusion the prevalence of obesity in diabetic children and adolescents is quite similar to the prevalence reported in their non-diabetic peers. Obesity and BMI excess correlate with female gender but are independent of insulin requirement and metabolic control.