Mortality and Apolipoprotein E in Hispanic, African-American, and Caucasian elders

Abstract

To investigate whether mortality risk is influenced by apolipoprotein E (APOE) genotype and whether the risk differs by ethnicity, we compared the mortality risk in 2,112 individuals > or = 65 years of age residing in northern Manhattan in New York. Mortality risks associated with the APOE genotype, adjusted for sex, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and triglycerides, differed significantly by ethnic group. Among Caucasian and Hispanics, the E2/E3 genotype was associated with the lowest mortality risk in the multivariate Cox proportional hazards modeling, adjusted for lipid levels, whereas mortality risk did not differ substantially between the E4/E3 and E3/E3 genotypes. Among African-Americans, the E2/E3 genotype was not associated with the lowest mortality risk, but the E4/E3 genotype was. Adjustment for heart disease, diabetes, and stroke reduced mortality risk associated with each genotype by about 50% for all ethnic groups, but the patterns remained the same. Although we cannot rule out the possibility of a healthy survival bias, our analyses designed to examine healthy survival by comparing risk of mortality in groups who were younger or older at entry do not support this possibility. Our findings suggest that the APOE genotype is associated with mortality and that the genotypic risks differ by ethnic group. Nearly 50% of the mortality risk associated with the APOE genotype appears to act through major chronic diseases, but those diseases only partially explain the mechanism by which the genotypic risk acts. To better understand the observed ethnic differences in mortality risk by genotype, a detailed prospective study is needed to examine the relationships among APOE, other candidate genes, health conditions, and eventual death.

Apolipoprotein E and mortality in African-Americans and Yoruba

“…In a multi ethnic study, Lee et al reported that in African Americans the ε3/ε4 genotype was associated with the lowest mortality risk whereas the subjects with ε3/ε3 genotypes had the highest risk. These findings were unchanged after stratifying by age group [10]. In our study of the older African-Americans, subjects with an ε4 allele did have lower mortality risks than those without but this difference was not significant.…”

“…In addition, 41.9% of the young cohort and 35.1% of the older cohort had heart disease. In Lee's study on African-Americans, 16.3% had diabetes and 24.6% of the subjects had heart disease [10]. Thus, it might be difficult to compare our results with those of Lee because of the differences in health between the groups.…”

“…Lee et al found different associations between mortality risk and ApoE between Caucasians, Hispanics and African Americans aged 65 and older living in northern Manhattan. He reported that the ε2/ε3 genotype was associated with the lowest mortality risk in the Caucasians and Hispanics, while the ε3/ε4 genotype was associated with the lowest mortality risk in African-Americans, even after stratifying by age group [10]. With Caucasians, no association was found between mortality risk and ApoE ε4 in citizens from Vantaa age 85 and older or Finnish subjects age 69-78 [8,9].…”

Human Longevity: Nature versus Nurture, Survival versus Mortality~!2010-04-29~!2010-06-30~!2010-08-31~!

“…In our study we expect that the number of survival in both gender will be similar, but as we observed that the deviations (differences between observed and expected), were different. When we compare the survival rate among both gender at age group (60)(61)(62)(63)(64)(65)(66)(67)(68)(69)(70)(71)(72)(73)(74) in 1995 vs. (73)(74)(75)(76)(77)(78)(79)(80)(81)(82)(83)(84)(85)(86)(87) in 2008, we observed more survival among males comparing to females (p=0.003), this means that the rate of mortality was higher among females, and the rate of survival was higher among males (p=0.003). Indeed, in 2008 we expected to have 86 males alive but we were surprised to find 108 males alive, in contrary we expected to have more females alive (157), but we only found 135 alive at 2008.…”

“…However, different studies have reported mixed results in concerning the issue of longevity, with some documenting null findings for APOE e4 and longevity [59,60], and others showing negative associations in subgroups only [61].…”