THE APOLIPOPROTEIN-E ALLELE EPSILON-4 DOES NOT CORRELATE WITH THE NUMBER OF SENILE PLAQUES OR NEUROFIBRILLARY TANGLES IN PATIENTS WITH ALZHEIMERS-DISEASE

Background and objectives-Apolipo-protein E (apoE) has been implicated in regenerative processes in the brain after trauma, as well as in th e pathogenesis of Alzheimer's disease. Inheritance of a specific apoe allele (apo epsilon 4) determines in part the risk and the mean age at onset of Alzheimer's disease. ApoE has been found to bind isoform spe cifically to beta-amyloid protein, the major component of senile plaqu es, and to the microtubule associated protein tau, which forms paired helical filaments and neurofibrillary tangles. The aim was to further examine the relation between apoe alleles, especially apo epsilon 4, a nd the development of neuropathological changes associated with Alzhei mer's disease. Methods-Brains of patients with Alzheimer's disease (n = 44) and vascular dementia (n = 11) and of age matched controls (n = 29) were studied. Senile plaques and neurofibrillary tangles in the hi ppocampus and frontal cortex were quantified. Results-No correlation w as found between the number of apo epsilon 4 alleles and the number of senile plaques and neurofibrillary tangles in the hippocampus or the frontal cortex of patients with Alzheimer's disease, or vascular demen tia, or control groups. No significant differences in duration or seve rity of dementia were found between patients with or without the apo e psilon 4 allele. No increased frequency of apo epsilon 4 was found in vascular dementia. Conclusion and comment-Although the apoe genotype c learly affects whether Alzheimer's disease will develop or not, the pr esent study suggests that it has no influence on pathology or clinical intellectual status, once the dementia has manifested itself. No incr eased apo epsilon 4 allele frequency was found in neuropathologically diagnosed patients with vascular dementia in whom concomitant Alzheime r's disease can be excluded.