Vision and hallucinations in older adults - PROJECT SUMMARY Visual hallucinations affect approximately 20% of Alzheimer disease and 50% of all Parkinson disease patients. Hallucinations are a leading source of patient and caregiver distress and are an independent risk factor for injury, nursing home placement, and mortality. Because treatment options for hallucinations are limited and have significant adverse effect risks, the prevention of hallucinations would have a transformative public health impact for older adults with neurodegenerative disease. Visual impairment is a risk factor for hallucinations, and since up to half of all vision loss in the U.S. is preventable or treatable, the prevention and treatment of ophthalmic disease could prevent or reduce the severity of hallucinations in older adults. However, studies of specific age-related eye diseases and hallucination outcomes are lacking, limiting these improvements in healthcare. This proposal requests support for a mentored career development award for Dr. Ali Hamedani, a neurology-trained neuro-ophthalmologist and epidemiologist at the University of Pennsylvania. The overarching goal of this project is to understand how visual pathway structure, function, diseases, and treatments contribute to hallucinations in older adults. In Aim 1, Dr. Hamedani will analyze longitudinal data from two Medicare-linked national health surveys (the National Health and Aging Trends Study and Health and Retirement Study) to determine whether age-related macular degeneration, primary open-angle glaucoma, and cataract surgery are associated with the incidence of hallucinations in a nationally representative sample of 5,200 high-risk older adults using advanced survival analysis with marginal structural models to account for time-dependent confounding. In Aim 2, Dr. Hamedani will recruit a prospective cohort of Parkinson disease patients who are beginning a medication for hallucinations to determine whether low-contrast acuity and retinal ganglion cell thickness are associated with hallucination severity and treatment response. In executing these aims, Dr. Hamedani will be obtain additional training in ophthalmic epidemiology, retinal imaging, and biostatistics under the mentorship of experts in optical coherence tomography and ophthalmic clinical investigation (Joel Schuman, MD) and neurodegenerative disease epidemiology and health services research (Allison Willis, MD MSCI). The results of this project will provide fundamental knowledge about the visual system’s role in causing hallucinations and pave the way for future studies to test visual impairment and ophthalmic disease as a prevention target for hallucinations and other neurocognitive outcomes in older adults. Through the research training and mentorship experience gained during this career development award, Dr. Hamedani will establish himself as an independent investigator in the applied epidemiology and outcomes research of ophthalmology in aging and neurodegenerative disease.
