The 2024 EASO framework, which integrates central adiposity with morbidity status, refines heart failure risk stratification by demonstrating that morbidity presence—not BMI threshold—is the primary determinant of HF vulnerability across all adiposity categories.
Key Findings
Results
The EASO framework reclassified 15.6% of conventionally overweight individuals as obese, substantially increasing estimated obesity prevalence.
Study population: 449,550 UK Biobank participants with a median follow-up of 15.5 years.
The reclassification increased obesity prevalence from 24.5% to 40.1%.
Reclassification applied to individuals with BMI 25–<30 kg/m² who had WHtR ≥0.5 plus ≥1 morbidity condition.
Morbidity was defined per the 2024 EASO consensus criteria as presence of ≥1 medical, functional, or psychological conditions associated with excess adiposity.
Results
Overweight individuals without central adiposity or morbidity (EASO overweight) had the lowest heart failure risk, below that of normal-weight individuals.
EASO overweight was defined as BMI 25–<30 kg/m² with WHtR <0.5 and/or absence of morbidity.
HR for incident HF compared with normal-weight individuals: 0.84 (95% CI 0.80–0.89).
This finding confirms that 'overweight per se confers no excess risk in the absence of morbidity.'
Cox proportional hazard models were used to estimate HRs for incident HF.
Results
Overweight individuals with central adiposity and morbidity (EASO new obesity) had significantly elevated heart failure risk despite BMI remaining below 30 kg/m².
EASO new obesity was defined as BMI 25–<30 kg/m² with WHtR ≥0.5 plus ≥1 morbidity.
HR for incident HF compared with normal-weight individuals: 1.32 (95% CI 1.25–1.39).
This demonstrates that 'morbidity presence—not BMI threshold—drives elevated HF risk within the overweight range.'
The contrast between EASO overweight (HR 0.84) and EASO new obesity (HR 1.32) highlights the heterogeneity within the conventional overweight BMI category.
Results
Conventional BMI obesity (BMI ≥30 kg/m²) yielded the highest summary heart failure hazard ratio, attributed to compositional enrichment with high-morbidity individuals rather than superior risk discrimination.
Summary HR for BMI obesity (BMI ≥30 kg/m²) compared with normal-weight: 1.62 (95% CI 1.53–1.71).
The authors attributed the high summary HR to 'compositional enrichment with high-morbidity individuals rather than superior risk discrimination.'
This suggests that the BMI ≥30 threshold groups together individuals with heterogeneous metabolic risk profiles.
Results
In the extended EASO framework, morbidity status produced a consistent upward shift in heart failure risk across all adiposity categories.
The extended framework additionally stratified individuals with BMI ≥30 kg/m² by morbidity status, beyond the standard EASO framework.
Morbidity status produced a 'consistent vertical upward shift in HF risk across all adiposity categories.'
This establishes 'phenotypic characterisation beyond anthropometric thresholds as the key determinant of HF vulnerability.'
The finding held across normal-weight, overweight, and obese BMI categories.
Methods
Three obesity classification systems were compared to evaluate their ability to stratify heart failure risk in a large prospective cohort.
Definition 1: Conventional BMI ≥30 kg/m².
Definition 2: The 2024 EASO framework integrating central adiposity (WHtR) with medical, functional, and psychological morbidity for the BMI 25–<30 kg/m² range.
Definition 3: An extended EASO framework that additionally stratified BMI ≥30 kg/m² individuals by morbidity status.
Cox proportional hazard models were used with normal-weight (BMI 18.5–<25 kg/m²) as the reference category.
What This Means
This research suggests that the standard method of classifying obesity using body mass index (BMI) alone misses important differences in heart failure risk among people with similar weights. The study used data from nearly 450,000 UK Biobank participants followed for an average of 15.5 years and compared three ways of defining obesity. The key innovation was applying the 2024 European obesity framework, which goes beyond BMI to also consider waist-to-height ratio (a measure of belly fat) and the presence of health conditions like diabetes, high blood pressure, or physical limitations that are linked to excess body fat.
The results showed that people with BMI in the 'overweight' range (25–30 kg/m²) are not a uniform group when it comes to heart failure risk. Those without central obesity or related health conditions actually had a lower heart failure risk than normal-weight people. In contrast, overweight people who did have central obesity and at least one related health condition had a 32% higher heart failure risk than normal-weight people—a level of risk that conventional BMI classification would have missed entirely. When the framework was extended to also sort people with BMI over 30 by their health condition status, morbidity consistently pushed heart failure risk higher regardless of which weight category a person fell into.
This research suggests that whether someone has obesity-related health conditions matters more for predicting heart failure than the BMI number alone. The findings support moving toward a more detailed, health-condition-based approach to classifying obesity in cardiovascular risk assessment, which could help identify high-risk individuals who might otherwise be overlooked because their BMI falls below the traditional obesity cutoff of 30 kg/m².
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Tang L, Tang X, Xing Z, Wu C. (2026). Redefining Obesity Risk for Heart Failure: Incorporating Morbidity Into the 2024 EASO Framework Definition of Obesity.. Diabetes/metabolism research and reviews. https://doi.org/10.1002/dmrr.70227