Validation of the 2024 European Association for the Study of Obesity diagnostic criteria: A comprehensive assessment of obesity-related mortality risks.

Abstract

Aims: Obesity is a global public health challenge, and the traditional WHO-proposed diagnostic criteria based on body mass index (BMI) often fail to fully assess related health risks. The European Association for the Study of Obesity (EASO) has proposed new criteria that combine BMI, waist-to-height ratio (WtHR) and complications to more accurately evaluate obesity-related health risks.

Materials and methods: This study utilized data from the National Health and Nutrition Examination Survey database, covering the years 1999-2018. The study validated the new EASO criteria for diagnosing obesity, defined as BMI ≥25 kg/m², WtHR ≥0.5 and the presence of 12 obesity-related complications. The associations between obesity and mortality were assessed using Kaplan-Meier survival curves and Cox proportional hazards regression analyses. Mediation analysis was conducted to explore potential mechanisms by which obesity impacts patient prognosis.

Results: A total of 39 066 participants were included, with a mean age of 43.6 years; 51.3% were male. Over a median follow-up period of 141 months, 3708 deaths were recorded. The prevalence of obesity was 63.04% according to the new EASO criteria. The obesity rate based on BMI ≥30 is only 35.55%. The EASO criteria achieved a C-index of 0.5549, which surpasses the predictive accuracy of the traditional BMI ≥30 kg/m² criterion, with a C-index of 0.5265. Cox regression analysis indicated that when using the traditional BMI ≥30 criterion to diagnose obesity, it was associated with all-cause mortality and cardiovascular disease (CVD)-related mortality, but it did not predict cancer-related mortality. Obesity diagnosed by EASO criteria was significantly associated with an increased risk of all-cause mortality (hazard ratio [HR] and 95% confidence interval [CI]: 1.13 [1.02, 1.24]), CVD mortality (HR and 95% CI: 1.48 [1.20, 1.83]) and cancer mortality (HR and 95% CI: 1.26 [1.03, 1.54]). When using simplified BMI ≥25 kg/m², WtHR ≥0.5 and any of the top five complications (diabetes mellitus, hypertension, CVD, metabolic syndrome and ageing) as diagnostic criteria, which had the highest C-index (0.612), obesity remained an independent prognostic factor for poor overall survival (HR and 95% CI for all-cause mortality: 1.41 [1.26, 1.58], HR for CVD mortality: 2.08 [1.61, 2.68] and HR for cancer mortality: 1.32 [1.06, 1.65]).

Conclusions: This study confirms the prognostic value of the new obesity diagnostic criteria proposed by EASO, suggesting that these criteria offer a more accurate assessment of obesity-related health risks.