Purpose: To investigate whether primary open-angle glaucoma (POAG) is associated with increased risk of developing Alzheimer disease (AD).
Methods: In a nationwide case register linkage study of patients with hospital admission or outpatient contact during the period from 1977 to 2001 in Denmark, the rate of subsequent AD for patients with a diagnosis of POAG was compared with the rate for patients with primary angle-closure glaucoma (PACG), cataract, and osteoarthritis (OA) and with the rate for the general population.
Results: A total of 11,721 patients with a diagnosis of POAG (including normal tension glaucoma), 5975 patients with PACG, 162,640 patients with cataract, and 230,208 patients with OA were identified in the registers. Patients with POAG did not have increased rate of subsequent AD compared to patients with PACG, cataract, or OA or compared with the general population.
Conclusions: POAG was not associated with increased risk of developing AD. It cannot be excluded that this negative finding is due to diagnostic misclassification as register data were used.