Comparing two diagnostic frameworks for obesity in Mexican children attending a pediatric obesity clinic.

BACKGROUND: Body mass index (BMI) is widely used to assess pediatric obesity but does not fully capture adiposity-related organ dysfunction. The Clinical Framework of Obesity 2025 (CFO-2025), proposed by The Lancet Diabetes & Endocrinology Commission, offers a complementary clinical approach. OBJECTIVE: To evaluate pediatric obesity classification using Centers for Disease Control and Prevention BMI (CDC-BMI) criteria and the CFO-2025, and to describe organ-system involvement in clinical obesity. METHODS: This cross-sectional study analyzed 220 patients aged 4-16 years from a pediatric obesity clinic in northeastern Mexico. Obesity was classified using CDC-BMI criteria and the CFO-2025 with pediatric adaptations. Under the CFO-2025, patients were categorized as having preclinical or clinical obesity based on organ-system involvement. Concordance was assessed using Cohen's kappa. RESULTS: Obesity prevalence was 80% by CDC-BMI criteria and 95% by the CFO-2025, with fair concordance (κ = 0.321; p < 0.001). Clinical obesity was identified in 83.2% of patients, including those classified as having normal weight or overweight by CDC-BMI; metabolic (73.2%) and cardiovascular (59%) systems were most frequently affected. CONCLUSIONS: Applied alongside BMI, the CFO-2025 identified additional multisystem involvement. Although not yet validated in children, it may support a more comprehensive clinical assessment of pediatric obesity. IMPACT: In the Pediatric Obesity Clinic at a referral hospital in northeastern Mexico, the Clinical Framework of Obesity 2025 (CFO-2025) classified a higher proportion of children as having obesity compared with the CDC-BMI criteria, with only fair concordance between systems. We provide preliminary pediatric evidence that the CFO-2025 identifies multisystem involvement, including metabolic and cardiovascular abnormalities, even among children categorized as normal weight or overweight by BMI. Although the CFO-2025 has not yet been validated in pediatric populations, integrating BMI with the CFO-2025 may support a more structured and comprehensive assessment of obesity-related organ involvement in children.