Traditional anthropometric parameters still predict metabolic disorders in women with severe obesity

It is well established that fat distribution rather than the total quantity of fat is the major determinant of cardiovascular risk in overweight subjects. However, it is not known whether the concept of fat distribution still makes sense in severely obese subjects. Particularly, the role of visceral fat accumulation and/or of adipocyte hypertrophy in insulin resistance (IR) has not been studied in this population. Therefore, the aim of this study was to clarify the determinants of metabolic disorders in severely obese women. We performed a cross-sectional study in 237 severely obese women (BMI >35 kg/m(2)). We assessed total body fat mass and fat distribution by anthropometric measurements (BMI and waist-to-hip ratio (WHR)) and by dual-energy X-ray absorptiometry (DXA). In 22 women, we measured subcutaneous and visceral adipocyte size on surgical biopsies. Mean BMI was 44 +/- 7 kg/m(2) (range 35-77), mean age 37 +/- 11 years (range 18-61). Lipid parameters (triglycerides, high-density lipoprotein cholesterol) and IR markers (fasting insulin and homeostasis model assessment (HOMA) index) correlated with fat distribution, whereas inflammatory parameters (C-reactive protein, fibrinogen) correlated only with total fat mass. An association was observed between android fat distribution and adipocyte hypertrophy. Visceral adipocyte hypertrophy was associated with both IR and hypertension, whereas subcutaneous fat-cell size was linked only to hypertension. Our results obtained in a large cohort of women showed that fat distribution still predicts metabolic abnormalities in severe obesity. Furthermore, we found a cluster of associations among fat distribution, metabolic syndrome (MS), and adipocyte hypertrophy.