Association between APOE epsilon 2/epsilon 3/epsilon 4 polymorphism and disability severity in a national long-term care survey sample.
BACKGROUND
early studies reported controversial findings on association of apolipoprotein E (APOE) polymorphism with disability.


OBJECTIVE
to analyse sex-specific associations of APOE genotypes with impairments in (instrumental) activities of daily living [(I)ADL] and mortality.


METHODS
population-based 1999 National Long Term Care Survey (NLTCS) of the US older (65+) individuals.


METHODS
genetic data are available for 1,805 individuals.


METHODS
each of six genotypes of three common alleles of the APOE locus (epsilon 2, epsilon 3 and epsilon 4) was tested on the association with a disability index or mortality.


RESULTS
APOE epsilon 3/epsilon 3 genotype significantly decreases odds ratio (OR) for IADL disability in males [OR = 0.48; 95% Confidence Interval (CI) 0.31-0.76] while it exhibits no association in females. The OR for ADL disability is 0.19 (CI 0.04-0.99) for epsilon 4/epsilon 4 female carriers. The epsilon 2/epsilon 3 genotype increases the chances of IADL disability for males (OR = 2.33; CI 1.28-4.25). No significant association between APOE polymorphism and mortality was found. A surprising observation was that epsilon 4/epsilon 4 female carriers have a 5.3 times lower chance of having ADL disability than non-epsilon 4/epsilon 4-carriers.


CONCLUSIONS
association of the APOE polymorphism with disability and lack of association with mortality support the view that APOE gene actions may be more significant as modulators of frailty than of longevity.
Kulminski
Alexander
A
Center for Population Health and Aging, Duke University Population Research Institute, Department of Sociology, Duke University, Trent Hall, Room 002, Durham, NC 27708, USA. Alexander.Kulminski@duke.edu
Ukraintseva
Svetlana V
SV
Arbeev
Konstantin G
KG
Manton
Kenneth G
KG
Oshima
Junko
J
Martin
George M
GM
Yashin
Anatoli I
AI
D000203:Activities of Daily Living; D000368:Aged; D053329:Apolipoprotein E2 / Q000235:genetics*; D053318:Apolipoprotein E3 / Q000235:genetics*; D053327:Apolipoprotein E4 / Q000235:genetics*; D006233:Persons with Disabilities; D005260:Female; D016330:Frail Elderly; D005838:Genotype; D006579:Heterozygote; D006801:Humans; D008134:Long-Term Care; D008136:Longevity / Q000235:genetics; D008297:Male; D011110:Polymorphism, Genetic; D012720:Severity of Illness Index; D014481:United States
D053329:Apolipoprotein E2; D053318:Apolipoprotein E3; D053327:Apolipoprotein E4