Clinical meaning
Pediatric obesity results from chronic energy imbalance, but the pathophysiology extends beyond simple caloric excess. Adipocyte hypertrophy and hyperplasia create a pro-inflammatory state with elevated IL-6, TNF-alpha, and leptin resistance, driving insulin resistance even before frank type 2 diabetes develops. In children, obesity during critical periods of adipocyte development (ages 5-7 and adolescence) programs persistent adiposity through epigenetic mechanisms. Unlike adults, BMI is age- and sex-specific in children: overweight = BMI 85th-94th percentile, obesity = BMI ≥ 95th percentile, severe obesity = BMI ≥ 120% of 95th percentile. Pediatric obesity carries unique complications including slipped capital femoral epiphysis, Blount disease (tibia vara), pseudotumor cerebri, and earlier onset of type 2 diabetes with more aggressive beta-cell decline than adult-onset T2DM.
Diagnosis & workup
Diagnostics & workup: - BMI calculation and percentile plotting on CDC growth chart (age 2-20) - Fasting lipid panel (dyslipidemia screening) - Fasting glucose and HbA1c (or OGTT if high risk for T2DM) - ALT (NAFLD screening — elevated in up to 40% of obese children) - TSH (thyroid screening to exclude endocrine cause) - Blood pressure with age/sex/height-appropriate percentile interpretation - Assess for comorbidities: sleep apnea symptoms, orthopedic symptoms, depression screening