APOE ε4 and Alzheimer's disease -: Positive association in a Colombian clinical series and review of the Latin-American studies

Objective: As the strength of the association between the APOE epsilon4 allele and Alzheimer's disease (AD) varies across ethnic groups, we studied if there was such an association in Colombian patients. Method: We performed apolipoprotein E (APOE) genotyping in a clinical sample of 83 unrelated AD patients, predominantly late-onset (>65 yrs) including familial (n = 30) and sporadic AD cases (n = 53) diagnosed according to NINCDS-ADRDA criteria and assessed by a multi-disciplinary team. Control subjects (n = 44) had no significant cognitive impairment by medical interview and neuro-psychological testing. Results: We found a high association (OR = 5.1 95%Cl 1.9 - 13.6) between APOE epsilon4 and AD, in this series with predominantly late-onset cases with familial aggregation in 24 cases (28.9%). A significant negative association was found between epsilon2 and AD (OR = 0.2 95% CI 0.05 - 0.75). Conclusion: Further population-based surveys in Colombia are warranted to precise a possible dose effect of APOE epsilon4.