Several studies have identified similarities in the pathogenic processes underlying Alzheimer's disease and glaucoma1-3 and reported a higher incidence of glaucoma among patients with Alzheimer's disease.4,5 A new hypothesis posits a direct causal link between these progressive neurodegenerative disorders.6
A retrospective case-controlled study by Berdahl et al found that patients with primary open-angle glaucoma had mean cerebrospinal fluid pressures that were 33% lower than those of nonglaucomatous controls (9.2 vs 13.0 mm Hg, respectively).7
In a separate study, Silverberg et al found that 96.1% of patients with Alzheimer's disease had statistically significantly lower mean cerebrospinal fluid pressures (103 ± 44 mm H2O [approximately 7.5 mm Hg]) than Alzheimer's patients with elevated cerebrospinal fluid pressures and a control group of younger patients with Parkinson's disease (140 ±60 mm H2O [approximately 10.3 mm Hg]).8
Extrapolating from the data published by Berdahl et al and Silverberg et al, Wostyn et al have proposed that a reduction in cerebrospinal fluid pressure may create an abnormally high difference in pressure across the lamina cribrosa, cause the porous structure to bow posteriorly, and lead to glaucomatous damage of the optic nerve. Normal IOP and cerebrospinal fluid pressure normally range from10 to 21 mm Hg and from 5 to 15 mm Hg, respectively.
According to Wostyn et al, investigators can test this hypothesis by comparing the cerebrospinal fluid pressures among Alzheimer's patients with glaucoma, Alzheimer's patients without glaucoma, and appropriate controls.6
TOP 5 ARTICLES FROM 2009
- Drug Delivery Systems in Ophthalmology
An update on products with potential for glaucoma therapy.
By Gary D. Novack, PhD
- Evaluating and Managing Optic Disc Cupping in Children
How to tell when a child has glaucoma.
By Allen Beck, MD
- Treating Glaucoma During Pregnancy
Preserving patients' vision is becoming increasingly important with advancing maternal age.
By Terri Pickering, MD
- Imaging Optic Nerve Head Drusen With Spectral Domain OCT
A new algorithm may help clinicians to determine the cause of visual field loss in patients with coexisting drusen and glaucoma.
By Huijuan Wu, MD, PhD; Johannes F. de Boer, PhD; and Teresa C. Chen, MD
- The Vascular Theory in Glaucoma
A focus on the endothelial cells.
By Barbara M. Wirostko, MD; Rita Ehrlich, MD; and Alon Harris, MS, PhD