Obesity Is an Important Determinant of Baseline Serum C-Reactive Protein Concentration in Monozygotic Twins, Independent of Genetic Influences

Abstract

Background— C-reactive protein (CRP) values predict atherothrombotic cardiovascular disease and type 2 diabetes mellitus. Associations between CRP and obesity, predominantly assessed anthropometrically, may partly explain these observations. Previous studies have been unable to control for genetic influences on CRP and obesity. The aim of this study was to examine the relationship between CRP and accurately measured body fat, lipids, apolipoproteins, blood pressure, and environmental and behavioral factors, independent of genetic influences. Methods and Results— One hundred ninety-four healthy female twins (age 57.2±7 years) were studied after excluding pairs with CRP values >10 mg/L. Total body fat and central abdominal fat (CAF) were measured by dual-energy x-ray absorptiometry. CRP concentration was strongly related to surrogate and direct measures of body fat ( r =0.31 to 0.54, P r =0.20, P =0.003), and lipid and apolipoprotein levels ( r =0.21 to 0.51, P r =0.39, P r =0.34, P =0.002), diastolic blood pressure ( r =0.24, P =0.03), apolipoprotein AI ( r =−0.33, P =0.01), HDL cholesterol ( r =−0.42, P =0.001), and triglycerides ( r =0.35, P =0.007). Conclusions— CRP was strongly related to total and central abdominal obesity, blood pressure, and lipid levels, independent of genetic influences. These relationships are likely to contribute significantly to prospective associations between CRP and type 2 diabetes and coronary events.