INS and obesity due to melanocortin 4 receptor deficiency: Children and adolescents with obesity at the initial assessment had significantly higher body weight, BMI, BMI z-score, waist circumference, hip circumference, waist to height ratio, fat percentage, fat mass, basal metabolic rate (BMR), T3 and insulin concentrations, and lower SHBG concentrations and HOMA-IR index than their overweight and normal-BMI counterparts both at the initial and annual assessment.