Abstract
Purpose: :
Based on retrospective chart reviews and case control studies that examined the incidence of open-angle glaucoma in patients with Alzheimer's disease, it has been hypothesized that there is a relationship between Alzheimer's disease and glaucoma. A common underlying pathogenetic mechanism has also been raised given that amyloid beta, a known player in Alzheimer's disease, has been implicated in retinal ganglion cell death. However, no studies to date have assessed whether patients with open-angle glaucoma have an increased risk of subsequent development of Alzheimer's disease and other dementias. Here we explore this relationship using longitudinal data from a nationally representative population of older persons.
Methods: :
A cohort of U.S. community-dwelling persons aged 65 and older was drawn from the Health and Retirement Study (HRS) and merged with Medicare claims data in 1996 with follow-up through 2002. The International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes specific to Alzheimer's disease, other dementias, and open-angle glaucoma were queried. The hazard ratio of time to development of Alzheimer's disease and other dementias was calculated considering whether or not a person had open-angle glaucoma at baseline using the Cox proportional hazards model, controlling for covariates such as age, gender, education, and race.
Results: :
Of 15,679 persons enrolled in the HRS, 481 developed Alzheimer's disease during the follow-up period. Multivariate analyses of development of Alzheimer's disease with a baseline diagnosis of open-angle glaucoma, controlling for age, gender, education, and race, were performed. We find a hazard ratio of 1.09 (p < 0.5) of developing Alzheimer's disease for those persons diagnosed with open-angle glaucoma at baseline. When the same analysis was repeated to examine the risk of developing any dementia including Alzheimer's disease, the hazard ratio was 1.08 (p < 0.35).
Conclusions: :
While there is limited evidence to suggest an increased incidence of open-angle glaucoma in patients with Alzheimer's disease, no such relationship was found when examining whether open-angle glaucoma patients have an increased risk of developing Alzheimer's disease or other dementias. Longitudinal analysis of health surveys merged with Medicare claims data may be a useful tool for examining uncommon relationships, such as between glaucoma and Alzheimer's disease, in the elderly population.
Keywords: clinical (human) or epidemiologic studies: prevalence/incidence