title: The effects of postmenopausal hormone use on cataract: a meta-analysis.
abstract: BACKGROUND
  Cataract is the leading cause of blindness worldwide. Many observational studies assessed the relationship between postmenopausal hormone replacement therapy (HRT) and risk of cataract development, but the reported results were controversial. The aim of present meta-analysis was to evaluate the association of postmenopausal hormone replacement therapy with risk of cataract development.
  
  
  METHODS
  The eligible observational studies, including cross-sectional, case-control and cohort studies, were identified by searching PubMed and Embase during March of 2013. Either a fixed- or a random-effects model was used to calculate the pooled odds ratio (OR) with its 95% confidence interval (95%CI). Subgroup analysis on cataract types was performed.
  
  
  RESULTS
  A total of four cohort and five case-control or cross-sectional studies were finally included into this meta-analysis. Overall, a significant decreased risk of developing any type of cataract was found in ever HRT group as compared with non-HRT group among cohort studies (OR 0.83; 95%CI: 0.71,0.97) and case-control or cross-sectional studies (OR 0.74; 95%CI: 0.59,0.93). Subgroup analysis on cataract types determined that the significantly decreased risk of nuclear cataract in current HRT group (OR 0.72; 95%CI: 0.61,0.85) and also a critically reduced risk of nuclear cataract in ever HRT group (OR 0.80; 95% CI: 0.64,1.01) were found among case-control or cross-sectional studies, as compared with non-HRT group. No association of HRT with risk of cortical and posterior subcapsular cataract was observed.
  
  
  CONCLUSIONS
  The results of present meta-analysis indicate that postmenopausal hormone use may play a protective role in cataract development.
authors.affiliation: Eye Center, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
authors.forename: Kairan
authors.initials: K
authors.lastname: Lai
authors.forename: Jiantao
authors.initials: J
authors.lastname: Cui
authors.forename: Shuang
authors.initials: S
authors.lastname: Ni
authors.forename: Yidong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Jiliang
authors.initials: J
authors.lastname: He
authors.forename: Ke
authors.initials: K
authors.lastname: Yao
mesh_terms: D016022:Case-Control Studies; D002386:Cataract / Q000139:chemically induced* / Q000453:epidemiology; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D015914:Estrogen Replacement Therapy / Q000009:adverse effects*; D006801:Humans