title: Erythropoietin levels in aqueous humor of patients with glaucoma.
abstract: OBJECTIVE
  To compare the aqueous concentration of erythropoietin (EPO) in eyes with primary open-angle (POAG), pseudoexfoliative (PXFG), and neovascular (NVG) glaucoma with age-matched eyes with cataracts, and to correlate its concentration with other factors including age, gender, intraocular pressure (IOP), type of glaucoma, and severity of glaucoma.
  
  
  METHODS
  In this prospective non-randomized comparative study, a total of 26 eyes with cataracts (control group) and 92 glaucomatous eyes (POAG, 40 eyes; PXFG, 26 eyes; NVG, 26 eyes) were enrolled. Aqueous samples (0.1 to 0.2 ml) were obtained during phacoemulsification, trabeculectomy, phacotrabeculectomy, or Ahmed valve glaucoma implants. The aqueous concentration of EPO was measured using an enzyme-linked immunosorbent assay.
  
  
  RESULTS
  The mean±SEM aqueous level of EPO was statistically significantly higher in eyes with glaucoma (56.7±9.3 mIU/ml) compared to the control group (0.8±0.51 mIU/ml; p<0.001). Eyes with NVG had the highest aqueous level of EPO. Aqueous EPO concentrations remained considerably elevated even in eyes with controlled IOP in all three types of glaucoma. Eyes with PXFG displayed the greatest change in aqueous EPO concentration proportionate to the IOP level. In simple regression analysis, IOP, mean deviation, and the type of glaucoma were the factors that had a statistically significantly positive correlation with the aqueous level of EPO (p=0.011 and <0.001, respectively). Only the type of glaucoma remained statistically significant in the multiple regression analysis (adjusted R(2)=0.278).
  
  
  CONCLUSIONS
  Compared to the control group, the aqueous humor EPO concentration is increased in eyes with POAG, PXFG, and NVG, both with and without controlled IOP. The aqueous level of EPO was more proportionate to the level of IOP in eyes with PXFG compared to eyes with POAG and NVG.
authors.affiliation: Department of Ophthalmology, Imam Hossein Medical Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran. nassiri@jsei.ucla.edu
authors.forename: Nader
authors.initials: N
authors.lastname: Nassiri
authors.forename: Nariman
authors.initials: N
authors.lastname: Nassiri
authors.forename: Mercede
authors.initials: M
authors.lastname: Majdi
authors.forename: Hadi Z
authors.initials: HZ
authors.lastname: Mehrjardi
authors.forename: Yadollah
authors.initials: Y
authors.lastname: Shakiba
authors.forename: Maryam
authors.initials: M
authors.lastname: Haghnegahdar
authors.forename: Amir Behzad
authors.initials: AB
authors.lastname: Heidari
authors.forename: Ali R
authors.initials: AR
authors.lastname: Djalilian
authors.forename: Mahroo
authors.initials: M
authors.lastname: Mirahmadian
mesh_terms: D000367:Age Factors; D000368:Aged; D001082:Aqueous Humor / Q000737:chemistry*; D002386:Cataract / Q000378:metabolism* / Q000473:pathology; D004921:Erythropoietin / Q000378:metabolism*; D017889:Exfoliation Syndrome / Q000378:metabolism* / Q000473:pathology; D005260:Female; D015355:Glaucoma, Neovascular / Q000378:metabolism* / Q000473:pathology; D005902:Glaucoma, Open-Angle / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012044:Regression Analysis; D012720:Severity of Illness Index; D012737:Sex Factors
chemical_list: C554270:EPO protein, human; D004921:Erythropoietin