Insulin, hs-CRP, leptin, and adiponectin. An analysis of their relationship to the metabolic syndrome in an obese population with an elevated waist circumference.

BACKGROUND: Various adipose tissue factors have been implicated as biomarkers of the metabolic syndrome (MS). The objective of this study was to assess which specific adipose tissue factors would discriminate the presence of MS in a strictly obese population meeting waist circumference (WC) criteria for the MS.

METHODS: This was a cross-sectional study of 148 subjects recruited from a university-based weight loss program prior to starting the program. Patients were eligible if they had a BMI more than 25 kg/m(2) and had WC more than 40 and 35 inches in males and females, respectively. Biomarkers measured included high sensitivity C-reactive protein (hs-CRP), leptin, adiponectin, and total insulin.

RESULTS: Of the total population, 33.8% satisfied criteria for the MS. Insulin was the only biomarker to consistently differentiate between presence and absence of MS in this obese population (P = 0.0001 in males, P = 0.006 in females). All biomarkers measured with the exception of leptin had a statistically significant relationship with increasing criteria for the MS.

CONCLUSIONS: In a population where an excess amount of adipose tissue exists, insulin is the only reliable biomarker to differentiate MS status. We surmise that differences in hs-CRP, leptin, and adiponectin are a reflection of their measurements in individuals with statistically different amounts of adipose tissue.