Lack of association of apolipoprotein E (Apo E) polymorphism with the prevalence of metabolic syndrome: The National Heart, Lung and Blood Institute Family Heart Study

Objective: Metabolic syndrome (MetS), characterized by abdominal obesity, atherogenic dyslipidaemia, elevated blood pressure and insulin resistance, is a major public health concern in the United States. The effects of apolipoprotein E (Apo E) polymorphism on MetS are not well established. Methods: We conducted a cross-sectional study consisting of 1551 participants from the National Heart, Lung and Blood Institute Family Heart Study to assess the relation of Apo E polymorphism with the prevalence of MetS. MetS was defined according to the American Heart Association-National Heart, Lung and Blood Institute-International Diabetes Federation-World Health Organization harmonized criteria. We used generalized estimating equations to estimate adjusted odds ratios (ORs) for prevalent MetS and the Bonferroni correction to account for multiple testing in the secondary analysis. Results: Our study population had a mean age (standard deviation) of 56.5 (11.0) years, and 49.7% had MetS. There was no association between the Apo E genotypes and the MetS. The multivariable adjusted ORs (95% confidence interval) were 1.00 (reference), 1.26 (0.31-5.21), 0.89 (0.62-1.29), 1.13 (0.61-2.10), 1.13 (0.88-1.47) and 1.87 (0.91-3.85) for the E{open}3/E{open}3, E{open}2/E{open}2, E{open}2/E{open}3, E{open}2/E{open}4, E{open}3/E{open}4 and E{open}4/E{open}4 genotypes, respectively. In a secondary analysis, E{open}2/E{open}3 genotype was associated with 41% lower prevalence odds of low high-density lipoprotein [multivariable adjusted ORs (95% confidence interval)=0.59 (0.36-0.95)] compared with E{open}3/E{open}3 genotype. Conclusions: Our findings do not support an association between Apo E polymorphism and MetS in a multicentre population-based study of predominantly White US men and women.