Further study needed to link Alzheimer’s, glaucoma
Alzheimer’s disease and glaucoma possess overlapping epidemiological and pathological changes, according to a study published in Eye.
“Epidemiological studies have shown that more Alzheimer’s patients may be suffering from glaucoma than the general healthy population,” Sagnik Sen, department of ophthalmology at the All India Institute of Medical Sciences, and colleagues wrote. “Present research points to a link between neurodegeneration in the brain and the optic nerve and inner retinal layers, which are an extension of the central nervous system in the form of a peripheral sense organ (the eye).”
In a review exploring the common pathways of these diseases involved in the pathogenesis and disease management, many previous studies have highlighted the overlapping features in both epidemiology and genetics. Findings include positive associations between glaucoma and Alzheimer’s disease (AD) involving aging patients as well as the importance of the apolipoprotein E gene as a major risk factor for AD and its need to be synthesized in the retina. Pathological changes in the retinal ganglion cells, nerve fiber layer, amyloid and beta-amyloid precursor protein, insulin receptors and neurodegeneration were also found to be common risk factors in patients.
Additional risk factors such as IOP, cerebrospinal fluid pressure and vascular flow regulation are still considered missing links in the association between these diseases.
“AD and glaucoma share multiple common biochemical and pathological changes. Both AD and glaucoma are slowly progressing age-related neurodegenerative disorders and may after all be manifestations of the same pathogenetic process with heterogenous presentations,” Sen concluded. “Long-term prospective cohort studies are required to determine the natural history of AD and its relation to glaucoma and related disorders.”