title: Diurnal intraocular pressure fluctuation and its risk factors in angle-closure and open-angle glaucoma.
abstract: OBJECTIVE
  To evaluate intraocular pressure (IOP) fluctuation during office hours and its predictive factors in untreated primary angle-closure suspects (PACS); post-iridotomy primary angle closure (PAC) and primary angle-closure glaucoma (PACG) eyes with or without IOP-lowering medication(s) as appropriate and medically treated primary open-angle glaucoma (POAG) eyes.
  
  
  METHODS
  One-hundred seventeen eyes (29 PACS, 30 PAC, 28 PACG, and 30 POAG) of 117 patients were included in this cross-sectional study. The subjects underwent hourly IOP measurements with Goldmann tonometer from 0800 to 1700 hours. Subjects with PAC and PACG had laser peripheral iridotomy at least 2 weeks prior to the inclusion. SD of office-hour IOP readings was the main outcome measure.
  
  
  RESULTS
  IOP fluctuation differed between the groups (P=0.01; Kruskal-Wallis Test). Post hoc Mann-Whitney U-tests showed significantly less IOP fluctuation in PACS compared with PACG (P<0.01). Peak office-hour IOP was observed in the morning in untreated subjects and in the early afternoon in treated subjects. A stepwise linear regression model identified the presence of peripheral anterior synechiae (PAS), thickness of lens, large vertical cup-to-disc ratio (VCDR), and PAC category as significant predictive factors associated with office-hour IOP fluctuation.
  
  
  CONCLUSIONS
  Diurnal IOP fluctuation in asymptomatic PACSs was less than that in treated PACG subjects and was at least comparable to that in treated PAC and POAG subjects. The greater the amount of PAS, the thicker the lens, the larger the VCDR, the greater was the IOP fluctuation during office hours.
authors.affiliation: Elite School of Optometry, Medical Research Foundation, Chennai, India.|Jadhavbhai Nathamal Singhvi Glaucoma Department, Medical Research Foundation, Sankara Nethralaya, Chennai, India.|Institute of Health and Biomedical Innovation, Queensland University of Technology, Queensland, Australia.
authors.forename: S
authors.initials: S
authors.lastname: Srinivasan
authors.affiliation: Jadhavbhai Nathamal Singhvi Glaucoma Department, Medical Research Foundation, Sankara Nethralaya, Chennai, India.|VST Glaucoma Centre, Dr Kallam Anji Reddy Campus, LV Prasad Eye Institute, Hyderabad, India.
authors.forename: N S
authors.initials: NS
authors.lastname: Choudhari
authors.affiliation: Jadhavbhai Nathamal Singhvi Glaucoma Department, Medical Research Foundation, Sankara Nethralaya, Chennai, India.|Singapore Eye Research Institute and Singapore National Eye Center, Singapore.
authors.forename: M
authors.initials: M
authors.lastname: Baskaran
authors.affiliation: Jadhavbhai Nathamal Singhvi Glaucoma Department, Medical Research Foundation, Sankara Nethralaya, Chennai, India.
authors.forename: R J
authors.initials: RJ
authors.lastname: George
authors.affiliation: Jadhavbhai Nathamal Singhvi Glaucoma Department, Medical Research Foundation, Sankara Nethralaya, Chennai, India.
authors.forename: B
authors.initials: B
authors.lastname: Shantha
authors.affiliation: Jadhavbhai Nathamal Singhvi Glaucoma Department, Medical Research Foundation, Sankara Nethralaya, Chennai, India.
authors.forename: L
authors.initials: L
authors.lastname: Vijaya
mesh_terms: D000368:Aged; D001699:Biometry; D002940:Circadian Rhythm / Q000502:physiology*; D063171:Corneal Pachymetry; D003430:Cross-Sectional Studies; D005260:Female; D015812:Glaucoma, Angle-Closure / Q000503:physiopathology* / Q000601:surgery; D005902:Glaucoma, Open-Angle / Q000503:physiopathology* / Q000601:surgery; D006068:Gonioscopy; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D032801:Iridectomy; D007498:Iris / Q000601:surgery; D017075:Laser Coagulation; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D014065:Tonometry, Ocular