title: [Prevalence of blindness and low vision among adults aged 50 years or above in Ji'an county of Jiangxi province: the China nine-province survey].
abstract: OBJECTIVE
  To estimate the prevalence of cataract, the outcomes of cataract surgery, cataract surgical coverage rate, cataract blindness social burden rate in Ji'an county of Jiangxi province, China.
  
  
  METHODS
  Cluster sampling was used in randomly selected 5010 individuals aged ≥ 50 years in Ji'an county of Jiangxi province. All individuals were received visual acuity and eye examination, including the evaluation of lens status and cataract surgical status by slit lamp biomicroscopy. Data bank was established by Epi-info Software. Statistical analyses were performed using Stata/SE Statistical Software, release 9.0 (Stata Corp, College Station, TX). Confidence intervals and P values (considered significance at the P < 0.05 level) for prevalence of cataract, cataract surgical coverage rate, cataract blindness social burden rate and outcomes of surgery were calculated with adjustment for clustering effects and stratification associated with the sampling design.
  
  
  RESULTS
  In 5010 individuals, 1158 cases of cataract were found, the prevalence of cataract was 23.11% among adults aged 50 or above. The prevalence of cataract was higher in the aged, female (P < 0.01). In 99 eyes with cataract surgery, 50.51% and 5.05% of eyes were performed by the modern extra-capsular surgery and phacoemulsification respectively. The rate of intraocular lens implantation was 55.56%. Post-operative presenting and best corrected visual acuity equal to or more than 0.7 was 10.1% and 45.5% of operated eyes respectively. The main causes of the post-operated eyes with worse visual acuity were post-capsular opacity and refractive error. The cataract surgical coverage rate was 32.29%, and the cataract blindness social burden rate was 3.83%. The cataract surgical rate was lower and cataract blindness social burden rate was higher in the aged persons (P < 0.01).
  
  
  CONCLUSIONS
  Cataract is the most common eye disease that may lead into blindness and severe visual impairment among older adults aged equal or more than 50 years. The cataract surgical coverage rate is not high but the cataract blindness social burden rate is heavy in Ji'an county. The rate of intraocular lens implantation need increase and the visual outcomes of the surgery should be further improved in the future.
authors.affiliation: Department of Ophthalmology, the Jiangxi Provincial People's Hospital, Nanchang 330006, China.
authors.forename: Rong
authors.initials: R
authors.lastname: Luo
authors.forename: Jia-liang
authors.initials: JL
authors.lastname: Zhao
authors.forename: Jing-lin
authors.initials: JL
authors.lastname: Yi
authors.forename: Hui
authors.initials: H
authors.lastname: Xie
authors.forename: Yong-quan
authors.initials: YQ
authors.lastname: Bai
authors.forename: Hai-jun
authors.initials: HJ
authors.lastname: Yang
authors.forename: Leon B
authors.initials: LB
authors.lastname: Ellwein
authors.forename: Ping-hong
authors.initials: PH
authors.lastname: Lai
authors.forename: Lan
authors.initials: L
authors.lastname: Li
authors.forename: Liang
authors.initials: L
authors.lastname: Huang
authors.forename: Hong-yan
authors.initials: HY
authors.lastname: DU
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.forename: Xue-cheng
authors.initials: XC
authors.lastname: Gao
authors.forename: Hong
authors.initials: H
authors.lastname: Lu
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001766:Blindness / Q000453:epidemiology*; D002386:Cataract / Q000453:epidemiology*; D002387:Cataract Extraction / Q000706:statistics & numerical data*; D002681:China / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence