Characteristics of Metabolic Syndrome in Morbidly Obese Subjects.

BACKGROUND: Metabolic syndrome (MetSyn) magnifies risks of cardiovascular disease (CVD) and type 2 diabetes, but its expression varies within the obese population. We examined body mass index (BMI), metabolic traits, and fat distribution in morbidly obese individuals.

METHODS: Lipids and inflammatory, oxidative stress and hepatic biomarkers in 346 women and 203 men (BMI ≥35 kg/m2 and co-morbidity or ≥40 kg/m2 ) were stratified by MetSyn components (1-5, excluding diabetes). Age- and smoking-adjusted partial correlations were calculated. Dual-energy X-ray absorptiometry was measured in 206 participants.

RESULTS: Apolipoprotein B, ferritin, uric acid, and alanine aminotransferase (ALT) concentrations worsened with increasing MetSyn components (P ≤ 0.0001), while BMI and LDL-cholesterol showed no association. BMI correlated inversely with triglycerides (r = -0.16, P = 0.03) and positively with HDL-cholesterol in men (r = 0.16, P = 0.02), but not in women. BMI correlated with C-reactive protein (CRP) (r = 0.32, P < 0.0001; r = 0.24, P < 0.0001 in men and women, respectively) and white blood cell count (r = 0.24, P = 0.001 in men; r = 0.15, P = 0.008 in women). Truncal fat percentage correlated to CRP (r = 0.31, P = 0.03; r = 0.20, P = 0.02 in men and women, respectively). In women, number of MetSyn components was inversely related to truncal and peripheral fat (r = -0.20, P = 0.02; r = -0.42, P < 0.0001, respectively) as was ALT (r = -0.21, P = 0.009; r = -0.38, P < 0.0001, respectively) and triglycerides with peripheral fat (r = -0.38, P < 0.0001), while HDL cholesterol was positively associated with truncal and peripheral fat (r = 0.26; P = 0.001).

CONCLUSIONS: BMI and fat distribution showed expected associations to inflammation biomarkers, but paradoxical relations between fat indices, and MetSyn components and biomarkers were seen. This suggests a need for better markers of CVD risk in morbid obesity.