title: Parity and the risk of cataract: a cross-sectional analysis in the Dongfeng-Tongji cohort study.
abstract: OBJECTIVE
  Epidemiological evidence showed that prevalence rates of cataract were higher in women than in men. Female reproductive factors were hypothesised to be linked with this sex difference. In this study, we explored possible effects of parity and reproductive factors on the risk of cataract.
  
  
  METHODS
  Women (14 337 total; aged 45-86 years) were recruited from the Dongfeng-Tongji cohort study. All subjects completed baseline questionnaires and medical examinations and provided baseline blood samples. Cataract was diagnosed by the ophthalmologist in the ocular examination. Logistic regression models were used to evaluate the association between parity and the risk of cataract.
  
  
  RESULTS
  The prevalence rate of cataract in the study population was 6.8% (972/14 337). After adjustment for potential confounders, women who had undergone two, three, and four or more live births had 1.52 times (95% CI 1.13 to 2.04), 1.67 times (95% CI 1.27 to 2.29) and 1.72 times (95% CI 1.22 to 2.42), respectively, higher risk of cataract compared with women who had undergone one live birth. The risk increased by an estimated 11.3% for each additional live birth. Women who had undergone hormone replacement therapy (OR 1.61; 95% CI 1.05 to 2.47), had diabetes mellitus (OR 1.33; 95% CI 1.11 to 1.58) and/or had the habit of drinking alcohol (OR 1.51; 95% CI 1.08 to 2.10) had a higher risk of cataract. Neither menopause status nor history of contraceptive use was associated with cataract.
  
  
  CONCLUSIONS
  The findings suggested that parity was an independent risk factor for the development of cataract in Chinese women.
authors.affiliation: MOE Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China.
authors.forename: Yaohua
authors.initials: Y
authors.lastname: Tian
authors.affiliation: MOE Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China Department of Maternal and Child Health, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wu
authors.affiliation: MOE Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China Department of Maternal and Child Health, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China.
authors.forename: Guiqiang
authors.initials: G
authors.lastname: Xu
authors.affiliation: MOE Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China Department of Maternal and Child Health, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China.
authors.forename: Lijun
authors.initials: L
authors.lastname: Shen
authors.affiliation: MOE Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China Department of Maternal and Child Health, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China.
authors.forename: Siyi
authors.initials: S
authors.lastname: Yang
authors.affiliation: MOE Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China Department of Maternal and Child Health, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China.
authors.forename: Chrispin
authors.initials: C
authors.lastname: Mandiwa
authors.affiliation: Dongfeng General Hospital, Dongfeng Motor Corporation and Hubei University of Medicine, Shiyan, China.
authors.forename: Handong
authors.initials: H
authors.lastname: Yang
authors.affiliation: Department of Social Medicine, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Liang
authors.affiliation: MOE Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China Department of Maternal and Child Health, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China.
authors.forename: Youjie
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000428:Alcohol Drinking / Q000453:epidemiology; D044466:Asian People; D002386:Cataract / Q000175:diagnosis / Q000453:epidemiology*; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D003920:Diabetes Mellitus / Q000453:epidemiology; D015914:Estrogen Replacement Therapy / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008875:Middle Aged; D010298:Parity; D010808:Physical Examination; D015995:Prevalence; D017584:Reproductive History; D012307:Risk Factors; D011795:Surveys and Questionnaires
keywords: Epidemiology; Public health