Different definitions of clinical obesity can help comprehensively identify individuals at-risk for cardiovascular disease, along with the standard body mass index (BMI) measurements, a research letter proposes. Dayhun Park, PhD, of the Institute for Biomaterials, Seoul, South Korea, and colleagues, reported these data in a manuscript published online Wednesday in JAMA Network Open. A new evidence-based definition of clinical obesity, including measurements of body fat and presence of organ dysfunction or physiological disruption due to greater amounts of adiposity, was recently proposed by the Lancet Diabetes & Endocrinology Commission. Investigators in this small, cross-sectional study examined patient data comparing the new definition of obesity with the standard BMI definition. They aimed to discover populations who could be misclassified by the standard BMI definition of obesity. Data were collected from the 2017-2018 NHANES (National Health and Nutrition Examination Survey) from the National Center for Health Statistics guidelines. Patients were measured for BMI-based obesity, defined as a BMI of 27.5 for non-Hispanic Asians and 30 or more for all other adults ≥20 years old, and clinical obesity, defined as meeting anthropometric and clinical criteria which included various physiological measures. The final sample included 4,990 adults (mean age=48.12 years, 51.69% female; 15.43% Hispanic, 11.38% non-Hispanic Black, 62.71% non-Hispanic White). BMI-based obesity was present in 43.81% of patients, which was comparable to clinical obesity at 44.74%. However, only 25.76% of patients were considered to have both BMI-based obesity and clinical obesity. The remaining 18.01% of patients had solely BMI-based obesity and 18.87% had clinical obesity. Rates of clinical obesity also increased with age. Additionally, low-income adults were more likely to have clinical obesity (53.16%), and so were adults who had fewer years of education (53.56%). Asians and Hispanics also had higher rates of clinical obesity (42.69%, 46.10%). Preclinical obesity was observed in 45.67% of adults with excess adiposity, but these rates went down as age went up. Adults with excess adiposity who were aged between 20 and 29 years saw 77.27% preclinical obesity, and those who were 80 years or older had only 8.49%. Organ dysfunction and limited mobility were more prevalent in adults who were older, women and socioeconomically disadvantaged, of the adults who had clinical obesity. The authors suggested that the clinical obesity definition provides reason for timely interventions to reduce obesity-related health problems, with interventions including pharmacotherapy, bariatric surgery or lifestyle changes. In young people, BMI versus clinical obesity measures yielded similar results, but the difference was more distinct in patients who were older. Older adults were more likely to be classified as obese by clinical obesity measures rather than BMI measures. “Collectively, our findings provide valuable insights into identifying individuals with obesity using different classifications,” the authors concluded. This research was funded by the Government of Korea. Source: Park D, Lee DH, Kim R, et al. Prevalence of clinical obesity in US adults based on a newly proposed definition. JAMA Network Open. 2025 September 25 (Article in press). Image Credit: Africa Studio – stock.adobe.com