AQUEOUS HUMOR β42-AMYLOID AND TOTAL PROTEINS CONCENTRATION IN GLAUCOMATOUS PATIENTS

Abstract

Purpose : Glaucoma shares some features with Alzheimer disease and other neurodegenerative disorders. We tested the association between glaucoma and total proteins (TP) and/or A-β42 concentration in the aqueous humor in a prospective clinical study.

Methods : Eighty-four patients were consecutively enrolled, 37 males and 47 females with a median age of 77 years. 86 eyes were examined, 34 were affected by glaucoma and 52 were healthy. Ophthalmological examination, biometry with Nidek Al-Scan and Lenstar Haag-Streit LS900 (axial length, anterior chamber depth, central corneal thickness were recorded), intraocular pressure (IOP) measurements with Goldman applanation tonometry, fundus examination, ganglion cells complex (mean thickness) and/or Retinal Nerve Fiber Layer (mean thickness) analysis with Optovue RTVue RT-100 OCT were performed unless unfeasible due to media opacities. Anti-glaucomatous pharmacological therapy was recorded. All patients were candidates for cataract surgery and were grouped according to the presence of glaucoma. During the procedure, an aqueous humor sample was collected and later processed with Enzyme-Linked Immunosorbent Assay (ELISA) method to detect TP and Aβ42 concentrations.

Results : A significant difference (p<0.05) was found for TP between healthy and glaucomatous subjects (3.38±1.03 mg/ml and 4.05±1.5 pM (mean± SD) respectively). A significant correlation was found between TP and A-β42 (r.0.45, p=0.002), pre-IOP (r.45, p<0.002) and age(r=-0.29, p<0.05). No difference was found between A-β42 and all the considered parameters between glaucomatous and healthy subjects.

Conclusions : Despite the lack of correlation between A-β42 aqueous humor concentration and the other parameters in glaucomatous patients, a significant correlation was found for TP concentration. This result outlined a possible role of aqueous humor proteins in glaucomatous disease pathogenesis.
Further studies on a large sample are thus warranted.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.