The relationship between apolipoprotein (apo) E polymorphism and lipid changes: An 8-year cohort study in Beijing elderly persons

This study aimed to investigate the influence of apoE genetic polymorphism on serum lipid changes in a community-based elderly population in China in an 8-year period, in which 746 individual, aged 65.29 ± 6.85 years (mean ± standard deviation (SD)) were enrolled and serum lipid parameters were checked at baseline. After 8 years, serum lipids as well as apoE genotypes were measured. The frequencies of apoE allele were 9.4%, 81.7%, and 8.9% for ɛ2, ɛ3 and ɛ4, respectively. After the population was divided into 3 groups by different apoE allele carriers, the apoE allele carriers for ɛ2, ɛ3 and ɛ4 were 121 (16.2%), 513 (68.8%) and 112 (15.0%), respectively. Levels of total cholesterol (TC) and low density lipoprotein (LDL) in ɛ2 carriers were lower comparing with that of ɛ3 allele carriers at baseline. 8 years later, TC and high density lipoprotein (HDL) elevated and LDL decreased with aging in this population (p < 0.01). The changes of TC levels were smaller in ɛ2 allele carriers as compared to that of ɛ3 allele carriers. The difference was still statistically significant after controlling for age, sex, smoking status, drinking habit, body mass index (BMI) and baseline TC level. The same trend of changes was noted for LDL between ɛ2 and ɛ3 allele carriers. However, no significant differences were noted between ɛ4 and ɛ3 allele carriers on lipid changes. This community-based study shows that ɛ2 allele is helpful on lipid changes. The effect of ɛ4 allele on lipid change is not strong in this elderly population. Genetic and environmental factors maybe co-operate on lipid metabolism in elderly persons.