Circulating oxidized LDL predicts future metabolic syndrome independent of lipid levels in the CARDIA study

Abstract

Experimental data suggest that oxidized LDL (oxLDL) is associated with the metabolic syndrome (MetSyn). However, this hypothesis has not been tested in man. To establish its relation with MetSyn, plasma oxLDL was measured with a competition monoclonal antibody based ELISA in 2823 Black and White participants in year 15 of the U.S. Coronary Artery Risk Development in Adults (CARDIA) study. Prevalence of MetSyn, following the Adult Treatment Panel III of the National Cholesterol Education Program, was 14.6% at year 15. The cross-sectional odds ratio for MetSyn in highest vs. lowest quintile of oxLDL was over 10, adjusted for age, gender, race, study center, cigarette smoking, BMI, physical activity, and LDL-cholesterol; little changed by further adjustment for C-reactive protein, and adiponectin. Cumulative 5-year MetSyn incidence was 13.3% (n = 254) in 1,909 participants free of MetSyn at year 15. The fully adjusted incidence OR in the highest vs. lowest quintile of oxLDL was 4.4 (95% CI 2.4–8.2). The incidence odds ratios for dichotomous MetSyn components in highest vs. lowest oxLDL quintile were 2.2 for abdominal obesity, 2.4 for triglycerides, and 2.5 for fasting glucose. Although oxLDL showed a graded relation to diabetes cross-sectionally, prediction of future diabetes was not significant. In conclusion, higher concentrations of oxLDL relate to concurrent presence of MetSyn and indicate a greater disposition to future MetSyn, especially abdominal obesity, hypertriglycemia, and glycemia.