Application of new Lancet Commission diagnostic criteria to 860 participants in an obesity drug trial revealed that nearly 20% were classified as having no obesity or pre-clinical obesity despite being enrolled for pharmacotherapy based on traditional BMI thresholds. The three-tier system evaluates excess adiposity, organ dysfunction, and daily activity limitations rather than relying solely on BMI cutoffs.
This diagnostic disconnect highlights a fundamental tension in obesity medicine between traditional anthropometric measures and newer functional assessments. The Lancet criteria attempt to capture obesity as a disease state requiring medical intervention, yet participants with identical BMI ranges (around 35 kg/m²) were scattered across diagnostic categories based on metabolic and functional parameters. Those classified as having no clinical obesity paradoxically showed greater psychological distress and more active weight management behaviors, suggesting these individuals may represent a distinct phenotype of metabolically healthier but psychologically burdened obesity.
The implementation challenges noted by researchers in this well-resourced clinical setting raise serious questions about real-world applicability. If specialized trial teams struggle with these criteria, routine clinical adoption seems problematic, potentially creating diagnostic inconsistencies that could affect treatment access and insurance coverage for obesity interventions.
