New obesity definition may delay treatment and complicate diagnosis

Redefining obesity based not only on body mass index (BMI) but on whether excess body fat is causing measurable health problems may complicate diagnosis and delay treatment, according to an Endocrine Society guideline communication published in The Journal of Clinical Endocrinology & Metabolism.

"How obesity is defined has real consequences for patients. Diagnostic definitions influence who qualifies for treatment, how clinicians manage care and how insurers determine coverage for medications and surgery," said author Ranganath Muniyappa, M.D., Ph.D., of the National Institute of Diabetes and Digestive and Kidney Diseases in Bethesda, Md. "Any new framework must be grounded in strong evidence, practical for everyday clinical use and designed to improve, rather than restrict equitable access to effective obesity treatment."

The authors highlight major conceptual and practical challenges with the Lancet Commission's proposed framework which requires clinicians to prove that organ dysfunction is caused by body fat to diagnose clinical obesity and introduces a "preclinical obesity" category for individuals without evidence of organ dysfunction.

The authors discuss how this approach may delay and complicate treatment and focus on three major concerns: 

• The framework's reliance on demonstrating that organ dysfunction is caused by excess body fat is difficult to implement in routine clinical care and may delay treatment or create barriers to access.
• The definition of "preclinical obesity" is conceptually unstable and dependent on the intensity of diagnostic testing, while the exclusion of type 2 diabetes from clinical criteria is inconsistent with current scientific and clinical evidence.
• The framework requires complex measurements and diagnostic evaluations that may not be feasible in many clinical settings and could exacerbate existing health inequities. 

The authors propose a more practical approach to diagnosing obesity that emphasizes clinical risk and functional impact, uses established staging approaches and ensures that new definitions improve care without creating barriers to treatment.

We need simpler ways to identify obesity earlier that don't involve rigid diagnostic thresholds and to focus on making sure people with obesity can access treatment based on how much it's likely to improve their daily lives and how safe it is-not on proving a single, exact cause. Future diagnostic frameworks should prioritize increasing access to obesity care and take a more nuanced approach."

Amy Rothberg, M.D., University of Michigan, Ann Arbor, Mich.

Other authors are Tariq Chukir of Weill Cornell Medicine-Qatar in Doha, Qatar; Dimpi Desai of Stanford University School of Medicine in Stanford, Calif.; Michael Weintraub of NYU Langone in New York, N.Y.; and Roma Gianchandani of Cedars-Sinai Medical Center in Los Angeles, Calif.

The study was funded by the Endocrine Society. The views expressed by Muniyappa are his own and do not necessarily reflect those of the National Institutes of Health (NIH), the U.S. Department of Health and Human Services (HHS), or the U.S. Government.