Abstract 3220: Adiponectin, Insulin Resistance (HOMA), and the HOMA/Adiponectin Ratio: Powerful Predictors of Prospective Coronary Heart Disease Risk in the Framingham Offspring Study
Our aim in this study was to evaluate the hypothesis that a low plasma adiponectin level is an independent predictor of coronary heart disease (CHD), since the data are conflicting. We measured adiponectin, glucose, and insulin levels in stored plasma samples (−80°C) in a total of 3,188 male and female participatants in cycle 6 of the Framingham Offspring Study (1995–1998). HOMA index was calculated as a parameter of insulin resistance. In the prospective analysis, we excluded CHD cases at baseline and followed up the rest of the participants for a mean of 7.5 years. At baseline, mean age was 57 years in both men and women, while the mean BMI was 28.5 kg/m2 in men and 27.3 kg/m2 in women. Plasma adiponectin levels (mean±SD) were significantly lower in female CHD cases than in female controls (13.8±6.8 vs. 15.8±7.8, p=0.0121), while in men, such differences did not reach a statistical significance (9.9±5.4 in CHD vs. 10.1±5.1 in controls, p=0.27). In the prospective analysis, we adjusted for age, smoking status, systolic blood pressure, treatment for hypertension, diabetes status, use of cholesterol-lowering medication, total cholesterol level, and high-density lipoprotein cholesterol level. After adjustment, a decreased plasma adiponec-tin level was a highly significant predictor of future CHD events (n-117) in men, with a hazards ratio of 0.4822 (p=0.0029). A bottom-quartile value of < 7.0 μ g/mL doubled the risk of CHD in men. This association was especially striking in overweight and obese individuals with insulin resistance. The identical trend was observed in women; however, the statistical significance of these associations disappeared after multivariate adjustments, probably due to a low number (60) of female CHD cases. Our data indicate that an adiponectin level of < 7.0 μ g/mL is a powerful independent predictor of heart disease in men, especially in overweight and obese with evidence of insulin resistance. The ratio of HOMA/adiponectin also appears to provide a highly discriminatory parameter for CHD risk assessment in men with similar trends in women. The measurement of insulin and adiponectin may provide excellent measures of CHD risk in overweight and obese men.