Those with clinical obesity have worse outcomes, despite having similar BMI levels and distributions
TUESDAY, Aug. 18, 2026 (HealthDay News) — Most metabolic and bariatric surgery (MBS) candidates meet criteria for clinical obesity (adiposity with obesity-related organ dysfunction), according to a study published online Aug. 11 in JAMA Network Open.
Simone Cremona, M.D., from King”s College London, and colleagues examined the prevalence of clinical and preclinical obesity (excess adiposity with preserved function) among MBS candidates in a retrospective, multicenter, cross-sectional study involving adults undergoing primary MBS between Jan. 1, 2014, and Dec. 31, 2025, at four tertiary centers in the United Kingdom, Spain, France, and Brazil.
The researchers found that 73.8 percent of the 2,316 participants had clinical obesity, and 26.2 percent had preclinical obesity. Across all centers, clinical obesity was the most prevalent category (from 62.7 to 79.3 percent in the Brazilian and U.K. cohorts). The mean body mass index (BMI) ranged from 40.2 to 48.5 kg/m2 (preclinical obesity in Brazilian and U.K. cohorts); BMI levels and category distributions were similar between clinical and preclinical obesity. Patients with clinical versus preclinical obesity were significantly older (e.g., mean, 48.9 versus 39.5 years in the U.K. cohort; mean, 45.6 versus 34.7 years in the French cohort) and had a higher American Society of Anesthesiologists classification, as well as higher estimated cardiovascular Framingham risk score and all-cause mortality risk. In the French cohort, increased 30-day major postoperative complications were seen in association with clinical versus preclinical obesity (4.0 versus 1.1 percent).
“The distinction between clinical and preclinical obesity is clinically meaningful even among surgical candidates with very high BMI levels, because BMI alone cannot tell us who has active disease,” senior author Francesco Rubino, M.D., from King”s College Hospital, said in a statement.
Several authors disclosed ties to the biopharmaceutical industry.
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