Delirium in the acute phase after stroke and the role of the apolipoprotein E gene.

OBJECTIVE: To study the association between the epsilon 4 allele of apolipoprotein E (APOEε4) and delirium in a stroke population. METHODS: 527 consecutive stroke patients were screened for delirium during the first week of admission with the confusion assessment method. In three hundred fifty-three patients genomic DNA isolation was available. RESULTS: The incidence of delirium after stroke in the 353 patients was 11.3%. There was no association between APOEε4 and delirium. Even after adjustment for IQCODE, stroke localization, stroke subtype, stroke severity, infection, and brain atrophy no association was found (odds ratio: 0.9; 95% confidence interval: 0.4-2.1). Delirium did not last longer in patients with an APOEε4 allele compared to patients without an APOEε4 allele (median: 5.6 days [range: 1-21] versus median: 4.6 days [range: 1-15], p = 0.5). CONCLUSION: There was no association between the presence of an APOEε4 allele and the occurrence of delirium in the acute phase after stroke.