Abstract
APOE ε4 is a major risk factor for Alzheimer's disease. It has also been associated with cognitive impairment and cognitive decline in young-olds, but the impact of the ε4 allele on cognitive function in very late life is still unclear. The object of this study was to evaluate the association of the ε4 allele of APOE with the cognitive performance of a sample of non-demented oldest-olds. Eighty-seven Spanish-speaking Puerto Rican non-demented nonagenarians were administered a complete neuropsychological assessment and provided a blood sample used for APOE genotyping. A factor analysis generated two factors: 1) verbal memory; and 2) visuo-spatial, naming and attention tasks, accounting for 43.6% of the overall variance in the 13 original neuropsychological variables. The multivariate analysis reflected, after controlling for gender, education, and age, the APOE ε4 carriers performed better in overall cognition (both factors analyzed together) than non-carriers (T2 = 0.082, F(2,80) = 3.289, p = 0.042). Neither gender nor the gender by APOE ε4 status interaction was associated with differences in cognition. In conclusion, the results of this study suggest that, among these Puerto Rican non-demented nonagenarians, being an APOE ε4 allele carrier is associated with better cognition.