title: Five-year incidence of age-related cataract and cataract surgery in the adult population of greater Beijing: the Beijing Eye Study.
abstract: OBJECTIVE
  To estimate the 5-year incidence of cataract and cataract surgery in an adult Chinese population.
  
  
  METHODS
  Population-based study.
  
  
  METHODS
  The Beijing Eye Study 2006 included 3251 (73.2%) subjects (≥45 years) of 4439 subjects who participated in the 2001 survey and returned for re-examination.
  
  
  METHODS
  Nuclear, cortical, and posterior subcapsular lens opacities were assessed based on standardized slit-lamp-based photographs and retroilluminated photographs of the lens using a modification of the grading score of the Age-Related Eye Disease Study.
  
  
  METHODS
  Incidence of any type of cataract and of cataract surgery.
  
  
  RESULTS
  The 5-year incidence of nuclear cataract was 5.98% (95% confidence intervals [CI], 5.96%-6.00%), that of cortical cataract was 11.14% (95% CI, 11.12%-11.17%), that of posterior subcapsular cataract was 5.47% (95% CI, 5.45%-5.48%), and that of cataract surgery was 2.01% (95% CI, 2.00%-2.02%). The incidence of any cataract (16.82%; 95% CI, 16.79%-16.86%) was significantly associated with higher age (P<0.001) and female gender (P<0.001). It was not significantly associated with the area of habitation (P = 0.78), smoking (P = 0.95), or alcohol consumption (P = 0.12). Differentiation into the 3 cataract types revealed that the incidence of nuclear cataract additionally was associated with rural region (P<0.001) and smoking (P<0.001). The incidence of cortical cataract additionally was associated with nonsmoking (P = 0.02). The incidence of cataract surgery was significantly (P<0.001) associated with age only.
  
  
  CONCLUSIONS
  As in white persons, the age-adjusted incidence of all types of cataract types increased with age and it was associated with female gender. When compared with data in the literature, the incidence rates of all cataract types did not vary markedly between Chinese in greater Beijing and white persons. In contrast, the incidence of cataract surgery was considerably lower in this Chinese population.
authors.affiliation: Beijing Institute of Ophthalmology, Beijing Tongren Hospital, Capital Medical University, Beijing, China.
authors.forename: Jing Shang
authors.initials: JS
authors.lastname: Zhang
authors.forename: Liang
authors.initials: L
authors.lastname: Xu
authors.forename: Ya Xing
authors.initials: YX
authors.lastname: Wang
authors.forename: Qi Sheng
authors.initials: QS
authors.lastname: You
authors.forename: Jin Da
authors.initials: JD
authors.lastname: Wang
authors.forename: Jost B
authors.initials: JB
authors.lastname: Jonas
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D044466:Asian People / Q000706:statistics & numerical data*; D002386:Cataract / Q000145:classification / Q000453:epidemiology*; D002387:Cataract Extraction / Q000706:statistics & numerical data*; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D010781:Photography; D012307:Risk Factors; D012424:Rural Population / Q000706:statistics & numerical data; D012907:Smoking / Q000453:epidemiology; D014505:Urban Population / Q000706:statistics & numerical data