Abstract 16865: Debunking the Concept That the “Metabolically Obese Normal Weight” Phenotype is Independent of Fat: It is All About Central Obesity

Abstract

Background: The Metabolically Obese Normal Weight (MONW) phenotype has been described as a unique subgroup of individuals with metabolic dysregulation similar to obese individuals, but not considered obese per se . In theory, these individuals have an adiposity-independent substrate predisposing them to metabolic dysregulation. We tested whether central obesity explains the metabolic abnormalities in persons with MONW in a prospective population-based cohort in the Czech Republic. Methods: We used data from Kardiovize Brno 2030 study, a prospective community-based cohort in Central Europe. We defined obesity using World Health Organization categories for body mass index (BMI) and central obesity by waist circumference (WC≥ 94 cm in men and ≥ 80 cm in women). Metabolically obese (MO) was defined using AHA criteria by having three or more of the following: Hypertriglyceridemia (≥ 1.7 mmol/l); HDL cholesterol level <1.0 mmol/l in men or <1.3 mmol/l in women; elevated blood pressure (systolic ≥ 130 mmHg and/or diastolic ≥ 85 mmHg) or antihypertensive drug treatment or history of hypertension; elevated fasting plasma glucose ≥ 5.6 mmol/l; or drug treatment and central obesity. Results: Of the 2,056 participants (46% men; mean age= 47.2 years, SD=11.2) included in the current analysis, 975 (47.4%) had normal weight and 696 (33.8%) were overweight. Prevalence of MO in the overall sample was 20.6% (n=424), 3.7% (n=36) among those with normal BMI and 9.9% (n=204) among overweight individuals. From the 36 subjects with MONW, 33 (91.6%) had central obesity by WC, while 201/204 (98.5%) with metabolically obese overweight, had central obesity by WC. Remarkably, in a subgroup of people with no metabolic obesity factors nobody had central obesity, see Figure . Conclusions: Metabolic dysregulation in people labeled as MONW can be explained by excessive visceral adiposity and not by an inherent predisposition, independent of adiposity.These findings underscore the importance of identifying central obesity in clinical practice even if BMI is below the obese criteria.