title: Increased urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG)/creatinine level is associated with the progression of normal-tension glaucoma.
abstract: OBJECTIVE
  The objective of this study was to investigate the association between systemic oxidative stress and visual field defect progression in normal-tension glaucoma (NTG).
  
  
  METHODS
  The subjects were 40 consecutive patients with NTG who were admitted to Keio University Hospital for 24-h intraocular pressure (IOP) evaluation; all subjects underwent six or more visual field tests in either eye and were followed up for >5 years. Spot samples of morning urine were collected during admission from all participants to determine the levels of urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) by ELISA kit. A linear regression line was calculated with the least squares method. Those subjects whose regression lines were negative and the p value <0.05 were classified as progressive, while all others were defined as non-progressive. Urinary 8-OHdG/creatinine level was compared between the two groups. Adjusted odds ratio and 95% confidence intervals for the progression were estimated with logistic regression models.
  
  
  RESULTS
  Seventeen subjects showed visual field defect progression (age: 59.9 ± 9.5 years, untreated IOP in the right eye: 15.8 ± 2.1 mmHg), and 23 subjects showed no progression (age: 57.4 ± 10.4 years, untreated IOP in the right eye: 16.0 ± 2.6 mmHg). Urinary 8-OHdG/creatinine level was significantly higher in the progressive group than in the non-progressive group (progressive group: 9.0 ± 2.4 ng/mg creatinine, non-progressive group: 7.3 ± 1.8 ng/mg creatinine, p = 0.02). Multivariable analysis revealed that higher urinary 8-OHdG/creatinine level was a significant risk factor for the progression (odds ratio 1.54, 95% confidence interval 1.03-2.29).
  
  
  CONCLUSIONS
  Increased urinary 8-OHdG/creatinine was associated with glaucomatous visual field progression in subjects with NTG.
authors.affiliation: Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan. yuuki@a3.keio.jp
authors.forename: Kenya
authors.initials: K
authors.lastname: Yuki
authors.forename: Kazuo
authors.initials: K
authors.lastname: Tsubota
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000652:urine; D003404:Creatinine / Q000652:urine*; D004249:DNA Damage; D003839:Deoxyadenosines / Q000652:urine*; D018450:Disease Progression; D005260:Female; D006801:Humans; D007429:Intraocular Pressure; D057066:Low Tension Glaucoma / Q000453:epidemiology* / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D018384:Oxidative Stress / Q000502:physiology*; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors; D014794:Visual Fields
chemical_list: C436623:8-hydroxy-2'-deoxyadenosine; D015415:Biomarkers; D003839:Deoxyadenosines; D003404:Creatinine