title: Central corneal thickness and glaucoma in East Asian people.
abstract: OBJECTIVE
  To examine the association between central corneal thickness (CCT) and glaucoma.
  
  
  METHODS
  This was a nested case-control study using 1090 subjects from an eye disease population survey in Singapore and 243 participants from a hospital glaucoma surgery clinical trial in Singapore.
  
  
  RESULTS
  Mean CCT in 938 community subjects was 539 μm ± 32 μm, and in 12 community subjects with primary open angle glaucoma (POAG) the mean CCT was 545 μm ± 38 μm. In the hospital cohort, mean CCT was 552 μm ± 38 μm in 138 patients with POAG and 551 μm ± 33 μm in 105 patients with primary angle closure glaucoma (PACG). No individuals had undergone previous intraocular surgery or had other significant ocular pathology. Regression models showed POAG diagnosis was not associated with CCT (P = 0.42) or age (P = 0.062) in community subjects but was associated with IOP (P = 0.005). Similar analyses for hospital cases showed CCT to be significantly higher in both POAG and PACG (both P = 0.001), but this became nonsignificant after controlling for IOP and age (P = 0.26, POAG; P = 0.08, PACG). Both age (P = 0.043) and IOP (P = 0.001) were highly associated with hospital POAG; only IOP (P = 0.001) was associated with hospital PACG. Further regression analyses for community subjects showed diabetic status and pseudophakia had no significant effect on CCT (P = 0.33 and P = 0.11, respectively).
  
  
  CONCLUSIONS
  The authors found no evidence to support the previous observation that thinner corneas may be independently associated with POAG or PACG. Age and IOP are significantly associated with CCT, and this should be taken into account by future studies investigating CCT as an independent risk factor for glaucoma diagnosis.
authors.affiliation: Division of Epidemiology and Genetics, University College London Institute of Ophthalmology, London, United Kingdom.
authors.forename: Alexander C
authors.initials: AC
authors.lastname: Day
authors.forename: David
authors.initials: D
authors.lastname: Machin
authors.forename: Tin
authors.initials: T
authors.lastname: Aung
authors.forename: Gus
authors.initials: G
authors.lastname: Gazzard
authors.forename: Rahat
authors.initials: R
authors.lastname: Husain
authors.forename: Paul T K
authors.initials: PT
authors.lastname: Chew
authors.forename: Peng T
authors.initials: PT
authors.lastname: Khaw
authors.forename: Steve K L
authors.initials: SK
authors.lastname: Seah
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Foster
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology; D000477:Alkylating Agents / Q000008:administration & dosage; D044466:Asian People / Q000208:ethnology; D016022:Case-Control Studies; D003315:Cornea / Q000473:pathology*; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D015812:Glaucoma, Angle-Closure / Q000175:diagnosis* / Q000208:ethnology / Q000601:surgery; D005902:Glaucoma, Open-Angle / Q000175:diagnosis* / Q000208:ethnology / Q000601:surgery; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012846:Singapore / Q000453:epidemiology; D014065:Tonometry, Ocular; D014130:Trabeculectomy; D058609:Visual Field Tests
chemical_list: D000477:Alkylating Agents; D005472:Fluorouracil