Risk factors for cataracts treated surgically in post-menopausal women

Objective: To identify risk factors for cataracts treated surgically in post-menopausal women. Design: Population-based, prospective cohort study. Participants: A total of 1,312,051 post-menopausal women in the UK Million Women Study, aged 56 years on average (SD 4.8), without previous cataract surgery, hospital admission with cataracts or cancer at baseline, were followed for cataracts treated surgically. Methods: Cox regression was used to calculate adjusted relative risks (RRs) for cataract surgery by lifestyle factors, treatment for diabetes, reproductive history and use of hormonal therapies. Main outcome measures: Cataract surgery identified by linkage to central National Health Service records for in-patient and day-patient admissions (Hospital Episode Statistics for England and Scottish Morbidity Records in Scotland). Results: Overall, 89,343 women underwent cataract surgery during an average of 11 (SD 3) years of follow-up. Women with diabetes were at greatest risk (diabetes vs no diabetes RR = 2.90, 95% CI 2.82-2.97). Other factors associated with an increased risk of cataract surgery were: current smoking (current smokers of >=15 cigarettes/day vs never smokers RR = 1.26, 95% CI 1.23-1.30) and obesity (BMI >=30 vs <25 kg/m2 RR = 1.12, 95% CI 1.10-1.14). Conclusions: Diabetes, smoking and obesity were risk factors for cataract surgery. Alcohol use, physical activity, reproductive history and use of hormonal therapies had little, if any, association with cataract surgery risk