Predictors of incident obesity phenotype in nonobese healthy adults.

BACKGROUND: Despite their different cardiovascular consequences, little is known about predictors of metabolically healthy (MHO) and metabolically unhealthy obesity (MUHO). This cohort study was designed to address this question in participants of the Tehran Lipid and Glucose Study.

MATERIALS AND METHODS: Employing the Joint Interim Statement (JIS) metabolic syndrome criteria to define MHO/MUHO phenotypes, nonobese, otherwise healthy individuals, aged > 20 years (n = 3489) were recruited and followed up for a median of 13·4 years.

RESULTS: At the follow-up, MHO incidence rate in obese individuals was 36·6%. Comparing MHO vs. MUHO, female gender [odds ratio (OR) = 3·28, 95% confidence interval (CI) 1·27, 8·46)], increased body mass index (BMI; OR = 1·32, 95% CI: 1·12, 1·60) and elevated high-density lipoprotein cholesterol (HDL-C) levels (OR = 1·04, 95% CI: 1·02, 1·07) were related to higher odds of incident MHO, while older age (OR = 0·95, 95% CI: 0·92, 0·98), increased waist circumference (WC; OR = 0·86, 95% CI: 0·81, 0·91), higher WC gain (OR = 0·91, 95% CI: 0·87, 0·95) and increased diastolic blood pressure (DBP; OR = 0·94, 95% CI: 0·91, 0·98) prevented progression towards MHO.

CONCLUSIONS: While baseline BMI and WC were detrimental for developing MHO vs. MUHO, gender was the strongest predictor of incident obesity phenotype in healthy nonobese individuals.