Introduction: Obesity is a heterogenous disorder. One of its subtypes that has been recently described is termed the metabolically healthy, but obese (MHO) individuals. Preliminary evidence suggests that this could be due to lower visceral fat levels and earlier onset of obesity.
Objectives: To determine the prevalence of MHO in a sample of obese patients. To evaluate whether body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) are significantly different between MHO and obese non metabolically healthy (NMHO) individuals.
Methods: The authors present a retrospective analysis of 254 obese patients (223 women and 31 men) evaluated in the obesity outpatient clinic of Hospital São João. Anthropometric variables, blood pressure (BP), fasting plasma levels of glucose (FPG), HDL cholesterol (HDL-C), triglycerides (TG) were measured. Insulin resistance (IR) was evaluated by the following index: homeostasis model assessment of insulin resistance (HOMA-IR), quantitative insulin sensitivity check index (QUICKI) and insulin sensitivity index-Matsuda (MATSUDA). MHO was defined by TG<150 mg/dl, HDL-C≥40 mg/dl (men) or ≥50 mg/dl (women), FPG<100 mg/dl, BP<130/85, HOMA-IR<2.5, QUICKI>0.33 and MATSUDA>5. Pearsons correlation coefficient, Students t-test and Fishers exact test were used for the statistical analysis.
Results: Patients had mean age of 39.7±11.2 years and mean BMI of 45.1±6.6 kg/m2. About 8.3% of these patients were MHO when all the above criteria are considered. If IR wasnt considered, the percentage increased to 15.7%. Patients classified as MHO had a significantly lower BMI, WC and WHR. Their age wasnt significantly different from NMHO individuals. BMI was positively correlated with all the IR index, WC (r=0.61; P<0.00001) and WHR (r=0.14; P<0.05).
Conclusions: In this study, only a small percentage of the obese patients were MHO. It almost doubled when IR was not considered, suggesting that this parameter is of early onset.
25 - 29 Apr 2009
European Society of Endocrinology