Trends in the prevalence of metabolically healthy and unhealthy obesity in the US adult population: analysis of eight NHANES cross-sectional survey cycles, 1999–2014

Abstract

ObjectiveTo exam the time trend of the prevalence of metabolically healthy obesity (MHO) in the US adult population.DesignEight cross-sectional survey cycles.SettingNational Health and Nutrition Examination Survey (NHANES), 1999–2014.Participants16 459 NHANES participants aged 20 years and older.Primary outcome measureMHO was defined as central obesity (waist circumference ≥102 cm for men and ≥88 cm for women) without any of the following conditions: elevated levels of blood pressure (≥130/85 mm Hg), glucose (≥100 mg/dL) and triglycerides (≥150 mm/dL); reduced levels of high-density lipoprotein cholesterol (<40 mg/dL for men and <50 mg/dL for women) or any medication use for high cholesterol, hypertension or diabetes.ResultsThe prevalence of central obesity significantly increased from 45.2% in 1999–2000 to 56.7% in 2013–2014 (p=0.003). Over the same period, MHO prevalence among those with central obesity only slightly and non-significantly increased from 11.0% to 15.7% (p=0.38). However, MHO prevalence among women increased significantly (p=0.04) from 7.1% to 13.7%. Female gender, a younger age, being Hispanic and non-Hispanic black and high education (some college or above) were significantly (p<0.05) associated with higher prevalence of MHO.ConclusionsWhile the prevalence of central obesity in the US population has increased since 1999, the prevalence of MHO among those who are centrally obese remained fairly stable.