Objectives:
Our objective was to examine the interrelationships of cardiovascular disease (CVD) risk factors with obesity, lipoproteins and their subfractions, markers of glucose homeostasis, and the inflammation markers adiponectin, and C reactive protein (hs-CRP).
Methods:
We measured fasting plasma lipids, low-density lipoprotein (LDL)-C, small dense LDL-C (sdLDL-C), high-density lipoprotein (HDL)-C, HDL subfractions, triglycerides, glucose, insulin, adiponectin, and hs-CRP in 2,691 male and female participants (median age 58 years) in cycle 6 of the Framingham Offspring Study. We carried out univariate and multivariate statistical analyses.
Results:
In both men and women the presence of obesity compared to those of normal weight was significantly (P<0.05) associated with: 1) a 60% increase in the prevalence of CVD, 2) a two to three fold higher prevalence of major CVD risk factors (hypertension, diabetes, and low HDL-C < 40 mg/dL), 3) a doubling of plasma levels of hsCRP, insulin, and triglycerides, 4) increased sdLDL-C, and 5) significant decreases in adiponectin and the levels of apoA-I in very large protective α-1 HDL. Surprisingly there was no relationship of obesity with levels of LDL-C in men. By multivariate analysis, in both men and women, adiponectin level emerged as the statistically most important parameter determining the variability of HDL-C and apoA-I levels in very large α-1 HDL, and sdLDL-C, while for systolic blood pressure age was the most important determinant, and for hsCRP levels it was plasma insulin levels. Interestingly over half of obese subjects were not hypertensive or prediabetic, and less than 20% had premature CVD or diabetes. By tertile analysis in obese subjects, low adiponectin was associated with a doubling of the prevalence of diabetes, and significant increases in triglycerides, and sdLDL-C (men only), and significant decreases in HDL-C and apoA-I in large α-1 HDL.
Conclusions:
Our data indicate that the prevalence of CVD and its risk factors increases with body mass index, and that the level of circulating adiponectin is a significant determinant of cardiovascular risk, especially diabetes prevalence, and levels of LDL and HDL subfractions in obese subjects.