title: Cognitive performance of primary open-angle glaucoma and normal-tension glaucoma patients.
abstract: OBJECTIVE
  To assess cognitive performance differences among primary open-angle glaucoma (POAG) patients, normal-tension glaucoma (NTG) patients, and healthy control (C) subjects.
  
  
  METHODS
  A total of 60 participants (20 POAG, 20 NTG, and 20 C subjects) were included in this study. A detailed ophthalmologic examination was performed on all participants. A spectral domain-optical coherence tomography (SD-OCT) system was used to measure the ganglion cell-inner plexiform layer (GC-IPL) and retinal nerve fiber layer (RNFL) thicknesses. To assess the cognitive performance of all participants, detailed neurological examinations, including the mini-mental state examination (MMSE), were performed by the same neurologist.
  
  
  RESULTS
  There were no significant differences among the groups in terms of age (p =0.348) or gender (p =0.935). The mean RNFL thicknesses were significantly different among the groups (85.2 ± 14.7, 76.8 ± 10.3, and 91.4 ± 7.7 µm in the POAG, NTG, and C subjects, respectively; p <0.001). The mean GC-IPL thicknesses were 77.5 ± 9.7 µm in the POAG group, 73.4 ± 7.8 µm in the NTG group, and 78.8 ± 3.8 µm in the C group. Differences among the groups were not statistically significant (p =0.085). MMSE scores were 26.1 ± 1.4, 25.7 ± 2.3, and 28.8 ± 0.9 in the POAG, NTG, and C groups, respectively. There were significant differences among the three groups (p <0.001). Specifically, there were significant differences between the NTG and C groups (p <0.001), and between the POAG and C groups (p =0.001). There was no significant difference between the POAG and NTG groups (p =0.595).
  
  
  CONCLUSIONS
  There appear to be similar risk factors in glaucoma and neurodegenerative disorders that cause deterioration in cognitive performance. Comparing the low MMSE scores of the POAG and NTG patients with the scores of healthy C participants supports our hypothesis. Consequently, it is recommended that a neurologist should also examine glaucoma patients.
authors.affiliation: Ophthalmology Department, Antalya Training and Research Hospital, Antalya, Turkey.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Bulut
authors.affiliation: Neurology Department, Antalya Training and Research Hospital, Antalya, Turkey.
authors.forename: Aylin
authors.initials: A
authors.lastname: Yaman
authors.affiliation: Ophthalmology Department, Antalya Training and Research Hospital, Antalya, Turkey.
authors.forename: Muhammet Kazim
authors.initials: MK
authors.lastname: Erol
authors.affiliation: Neurology Department, Antalya Training and Research Hospital, Antalya, Turkey.
authors.forename: Fatma
authors.initials: F
authors.lastname: Kurtuluş
authors.affiliation: Ophthalmology Department, Antalya Training and Research Hospital, Antalya, Turkey.
authors.forename: Devrim
authors.initials: D
authors.lastname: Toslak
authors.affiliation: Ophthalmology Department, Antalya Training and Research Hospital, Antalya, Turkey.
authors.forename: Deniz Turgut
authors.initials: DT
authors.lastname: Coban
authors.affiliation: Department of Animal Science Biometry and Genetics Unit, Faculty of Agriculture, Akdeniz University, Akdeniz, Turkey.
authors.forename: Ebru Kaya
authors.initials: EK
authors.lastname: Başar
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D003071:Cognition; D003704:Dementia / Q000175:diagnosis / Q000503:physiopathology; D005260:Female; D005902:Glaucoma, Open-Angle; D006801:Humans; D057066:Low Tension Glaucoma; D008297:Male; D008609:Mental Status Schedule / Q000706:statistics & numerical data*; D008875:Middle Aged; D009412:Nerve Fibers / Q000502:physiology; D012160:Retina / Q000033:anatomy & histology / Q000503:physiopathology; D012165:Retinal Ganglion Cells / Q000502:physiology; D041623:Tomography, Optical Coherence / Q000379:methods