ORIGINAL INVESTIGATION: APOE Genotype, Lipids, and Coronary Heart Disease Risk: A Prospective Population Study
P. N Mitrou,
N. J Wareham,
K. T Khaw
Background The risk of coronary heart disease (CHD) may be related to genetic mutations in the production of apolipoprotein E via alterations to the metabolism of CHD-related blood lipids such as low-density lipoprotein cholesterol and triglycerides.
Methods The relationship between APOE genotype (*E3/*E3, *E3/*E4, *E2/*E3, *E4/*E4, *E2/*E4, and *E2/*E2) and fatal and nonfatal CHD was examined among 10 035 men and 12 134 women, aged 440 to 79 years, from the Norfolk, England, arm of the European Prospective Into Nutrition and Cancer Study (1993-2007). During an average of 11 years of follow-up, 2712 CHD events were documented.
Results The hazard ratio for CHD was 0.88 (95% confidence interval, 0.77-0.99) for *E2 carriers (*E2/*E2 and *E2/*E3) and 1.09 (1.00-1.19) for *E4 carriers (*E3/*E4 and *E4/*E4) compared with homozygous *E3/*E3 individuals after age and sex adjustment. Similar values were obtained when systolic blood pressure, body mass index, diabetes mellitus, alcohol intake, physical activity, and smoking were added to the model. After additional adjustment for baseline levels of the ratio of low- to high-density lipoprotein cholesterol, the hazard ratios (and 95% confidence intervals) for *E2 and *E4 carriers were 0.97 (0.85-1.10) and 1.06 (0.97-1.15), respectively, when compared with *E3 homozygotes. No interactions by sex, smoking status, or age groups were observed.
Conclusion In the largest prospective cohort study to date, CHD risk was not associated with APOE genotype after controlling for a variety of cardiovascular risk factors, particularly the ratio of low- to high-density lipoprotein cholesterol.