Discordant Obesity Severity Classification Between the Edmonton Obesity Staging System and the Lancet Commission Model

ObjectiveBMI alone does not capture obesity-related health heterogeneity. The Edmonton Obesity Staging System (EOSS) grades obesity severity based on comorbidities and functional impairment, whereas the Lancet Commission Diagnostic Model for Obesity (DMO) distinguishes preclinical from clinical obesity based on organ dysfunction. We assessed whether both frameworks identify overlapping phenotypes and how they classify obesity severity. MethodsA modified EOSS and DMO were applied to the UK Biobank (N {approx} 411,000). Stage distributions, cross-classification, and the impact of combining BMI with fat distribution on obesity categorization were analyzed. ResultsAbout one quarter of participants were classified with obesity under both frameworks. Most were assigned to advanced stages, with high concordance for established disease. Differences were most pronounced in early stages: DMO captured a broader spectrum of mild/subclinical organ dysfunction, whereas EOSS emphasized established disease with prognostic relevance. Discrepancies reflected differences in operationalization of e.g. metabolic, cardiovascular, and mental health. Obesity thresholds influenced classification, with [~]50% reclassified when BMI was combined with different fat distribution parameters, highlighting sensitivity of early-stage assignment. ConclusionEOSS and DMO provide complementary perspectives on obesity severity. Integrating EOSSs prognostic granularity with DMOs multidimensional approach may improve risk stratification and identify individuals most suitable for intensive interventions. STUDY IMPORTANCEO_ST_ABSWhat is already known?C_ST_ABSO_LIBMI alone poorly reflects obesity-related health risk; comorbidities, organ dysfunction, and functional impairments are crucial for precise staging. C_LIO_LITwo major frameworks exist: EOSS focuses on prognostic severity, while DMO identifies early/preclinical obesity--but their agreement and clinical implications were unclear. C_LI What does this study add?O_LIDemonstrates that EOSS emphasizes established disease and prognostic severity, whereas DMO captures a broader spectrum of early or subclinical organ dysfunction, revealing distinct phenotypes within the same BMI-defined population. C_LIO_LIHighlights that combining BMI with anthropometric measures can reclassify up to [~]50% of individuals, illustrating the sensitivity of early-stage assignment to diagnostic thresholds. C_LI How might these results change the direction of research or the focus of clinical practice?O_LIIntegrating EOSSs prognostic detail with DMOs broad, multidimensional approach enables targeted intervention, helping clinicians prioritize patients for intensive obesity management or treatment. C_LIO_LIProvides evidence for harmonizing obesity classification beyond BMI, emphasizing the need for multidimensional assessment in both research cohorts and routine clinical practice. C_LI