High frequency of open-angle glaucoma in Japanese patients with Alzheimer's disease

The clinical and genetic relationships between Alzheimer's disease (AD) and glaucoma remain obscure. The aim of this study was to determine the prevalence of open-angle glaucoma (OAG) in patients with AD and whether the apolipoprotein E (APOE) 4 allele is associated with AD, with or without OAG, in Japanese. The groups consisted of 172 patients with the diagnostic criteria of AD and 176 age-matched controls. Ophthalmic examinations were conducted, and genomic analysis was performed by PCR and digestion of products with an enzyme. OAG was found in 41 (23.8%) of the AD patients, which was a significantly (p = 0.0002) higher prevalence than that in the controls (9.9%). Furthermore, there was no significant difference between intraocular pressures (IOPs) in AD patients with OAG and without OAG. The percentage of AD patients who carried an APOE ε4 allele (29.5%) was significantly (p = 0.0007) higher than that of the controls (9.1%). However, the percentage of AD patients with OAG who carried an APOE ε4 allele (35.7%) was not significantly different than that of AD patients without OAG (27.7%, p = 0.42). In summary, the prevalence of OAG is high in Japanese patients with AD, suggesting that common factors other than APOE may contribute to the two diseases.