Obesity in Children

Definition & Burden - The Growing Concern

• Definitions (WHO/IAP): Based on BMI-for-age.
  • Overweight: >+1SD to +2SD (or 85th-95th percentile).
  • Obesity: >+2SD (or ≥95th percentile).
  • Severe Obesity: >+3SD.
• Indian Burden: ↑ prevalence, especially urban > rural (NFHS data). A significant, growing epidemic.
• Screening: Annually for children >2 years using appropriate BMI charts.

⭐ IAP recommends using WHO growth charts for children 0-5 years and WHO reference charts for 5-18 years, with specific Indian consensus on BMI cutoffs.

Etiology & Risks - Unpacking Pounds

📌 Risk Factors Mnemonic: GELPP (Genetic, Environmental, Lifestyle, Perinatal, Parental)

• Genetic Factors: Strong heritability influences susceptibility.
  • Syndromic: Prader-Willi, Bardet-Biedl syndromes.
  • Monogenic: MC4R, leptin pathway defects (rare).

  ⭐ Mutations in the MC4R gene are the most common cause of monogenic obesity.

• Environmental Factors:
  • Obesogenic environment: ↑ access to calorie-dense foods, ↓ safe play areas.
  • Socioeconomic status (SES): Complex, varied impact.
• Lifestyle Factors:
  • Dietary: High calorie-dense foods, sugary drinks, ↓ fruits/vegetables intake.
  • Physical inactivity: ↑ screen time (e.g., >2 hrs/day), ↓ outdoor play.
  • Sleep: ↓ duration, disrupting appetite-regulating hormones.
• Perinatal Factors:
  • Maternal: GDM, pre-pregnancy obesity.
  • Infant: High birth weight (LGA), formula feeding (vs. breastfeeding).
• Parental Obesity: Very strong predictor (genetic predisposition & shared environment).

Assessment & Impact - Health Toll

Clinical Assessment:

• History: Detailed diet, physical activity levels, family Hx of obesity, T2DM, cardiovascular diseases.
• Examination:
  • BMI: Use WHO age & sex-specific charts. >+1SD (Overweight), >+2SD (Obesity), >+3SD (Severe Obesity).
  • Waist Circumference: >90th percentile suggests abdominal obesity.
  • Blood Pressure: Consistently ≥95th percentile for age, sex, and height indicates hypertension.
  • Signs: Acanthosis nigricans (neck, axillae), stigmata of syndromic obesity (e.g., Prader-Willi, Bardet-Biedl).

Investigations:

• Initial Labs: Fasting lipid profile, fasting glucose/HbA1c, LFTs (ALT, AST for NAFLD).
• Consider (if clinically suspected): TSH (hypothyroidism), morning cortisol/dexamethasone suppression test (Cushing's).

Health Toll (Systemic Complications):

• Metabolic: Insulin resistance, T2DM, dyslipidemia (↑TG, ↓HDL), NAFLD/NASH, PCOS.
• Cardiovascular: Hypertension, endothelial dysfunction, early atherosclerosis.
• Respiratory: Obstructive Sleep Apnea (OSA), asthma exacerbation, exercise intolerance.
• Orthopedic: Slipped Capital Femoral Epiphysis (SCFE), Blount's disease (tibia vara), ↑fracture risk.
• Gastrointestinal: GERD, cholelithiasis.
• Endocrine: Precocious puberty (girls), delayed puberty/hypogonadism (boys).
• Psychosocial: Depression, anxiety, low self-esteem, bullying, eating disorders, social stigmatization.

⭐ Acanthosis nigricans is a common clinical sign indicative of insulin resistance in obese children.

Management & Prevention - Turning Tides

Prevention Strategies:

• Primordial: Healthy environment & policies.
• Primary: Focus on 'First 1000 days', promoting healthy habits.
• Secondary: Early screening & detection.
• Tertiary: Manage complications, prevent progression.

IAP Stepwise Management Approach:

Cornerstone: Lifestyle Modification

• Dietary: 📌 5-2-1-0 GO! (≥5 fruits/veg, ≤2 hrs screen time, ≥1 hr physical activity, 0 sugary drinks).
• Activity: ↑ Regular physical activity (structured & unstructured).
• Behavioral: Reduce sedentary time, family-based interventions, motivational interviewing.

⭐ Family-based behavioral therapy is the most effective intervention for childhood obesity management.

Pharmacotherapy (Limited Role; Adolescents):

• Orlistat (age ≥12 yrs).
• Liraglutide (age ≥12 yrs).
• Metformin (for associated T2DM/IGT).

Bariatric Surgery (Rare; Severe Adolescent Obesity):

• Criteria: BMI >40 kg/m² or BMI >35 kg/m² with severe comorbidities.

High‑Yield Points - ⚡ Biggest Takeaways

• Obesity: BMI ≥ 95th percentile for age/sex or > +2 SD. Overweight: 85th-94th percentile.
• Screen children ≥ 6 years using BMI-for-age charts.
• Comorbidities: Type 2 DM, hypertension, dyslipidemia, NAFLD, sleep apnea.
• Etiology: Genetics, epigenetics, obesogenic environment (diet, inactivity).
• Management: Comprehensive lifestyle interventions (diet, activity, behavior therapy).
• Prevention: Promote healthy eating and physical activity from early childhood.
• Risk of adult metabolic syndrome & CVD (Cardiovascular Disease).