title: Prevalence and risk factors for angle-closure disease in a rural Northeast China population: a population-based survey in Bin County, Harbin.
abstract: OBJECTIVE
  To estimate the prevalence of primary angle-closure glaucoma (PACG), primary angle closure (PAC) and primary angle-closure suspect (PACS) and associated risk factors for PACG in a rural population in Northeast China.
  
  
  METHODS
  A population-based survey was conducted in Bin County, Harbin, Northeast China. Glaucoma was diagnosed using the International Society of Geographical and Epidemiological Ophthalmology (ISGEO) criteria. All subjects underwent a complete ophthalmic examination.
  
  
  RESULTS
  A total of 4956 (86.01%) of 5762 subjects aged 40 years or older were examined. The mean intraocular pressure (IOP) of the right eyes was 14.0 mmHg. The mean vertical cup-to-disc ratio of the right and the left eyes was 0.31 and 0.31, respectively. The prevalence of PACG, PAC and PACS was 1.57% [95% confidence interval (CI), 1.469-1.671], 1.33% (95% CI, 1.236-1.424), and 4.68% (95% CI, 4.541-4.819), respectively. Among all PACG subjects, 42 (53.84%) had elevated IOP >21 mmHg in either eye and 37 (47.44%) had been treated by laser, surgical iridectomy or trabeculectomy. Sixty-four subjects (82.05%) had vision impairment of varying degrees. Multivariate analysis revealed that old age, family history of PACG, constipation and IOP were significant independent risk factors.
  
  
  CONCLUSIONS
  Primary angle-closure glaucoma was a disease of high prevalence in rural Northeast China. Old age, family history of PACG, constipation and IOP were significant independent risk factors for PACG.
authors.affiliation: Department of Ophthalmology, The 2nd Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Qu
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Li
authors.forename: Wulian
authors.initials: W
authors.lastname: Song
authors.forename: Xinrong
authors.initials: X
authors.lastname: Zhou
authors.forename: Yang
authors.initials: Y
authors.lastname: Kang
authors.forename: Liping
authors.initials: L
authors.lastname: Yan
authors.forename: Hong
authors.initials: H
authors.lastname: Sui
authors.forename: Huiping
authors.initials: H
authors.lastname: Yuan
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D002681:China / Q000453:epidemiology; D015812:Glaucoma, Angle-Closure / Q000175:diagnosis / Q000453:epidemiology*; D006306:Health Surveys; D006801:Humans; D007429:Intraocular Pressure; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors; D012424:Rural Population / Q000706:statistics & numerical data*; D017678:Sex Distribution; D014065:Tonometry, Ocular