Association of apolipoprotein E phenotypes with late onset Alzheimer's disease: population based study.

OBJECTIVE

To determine the association between the e4 allele of apolipoprotein E and Alzheimer's disease in a randomly selected population sample.

DESIGN

Cross sectional population based study.

SUBJECTS: 980 people aged 69 to 78 (349 men, 631 women).

SETTING

Population of Kuopio, eastern Finland.

MAIN OUTCOME MEASURES: Presence of e4 allele and diagnosis of Alzheimer's disease by detailed neurological and neurophysiological evaluation.

RESULTS

46 (4.7%) subjects were classified as having probable or possible Alzheimer's disease. The frequency of the apolipoprotein E e4 allele was 0.359 in patients with Alzheimer's disease and 0.165 subjects without dementia (P < 0.0001). The prevalence of Alzheimer's disease was 2.9% in subjects with no e4 alleles, 7.6% in subjects with one e4 allele, and 21.4% in subjects with two e4 alleles of apolipoprotein E.

CONCLUSIONS

Allele e4 of apolipoprotein is associated with Alzheimer's disease in a dose-response fashion in a randomly selected elderly population.