title: Severe adverse events after cataract surgery among medicare beneficiaries.
abstract: OBJECTIVE
  To determine rates and risk factors associated with severe postoperative complications after cataract surgery and whether they have been changing over the past decade.
  
  
  METHODS
  Retrospective longitudinal cohort study.
  
  
  METHODS
  A total of 221 594 Medicare beneficiaries who underwent cataract surgery during 1994-2006.
  
  
  METHODS
  Beneficiaries were stratified into 3 cohorts: those who underwent initial cataract surgery during 1994-1995, 1999-2000, or 2005-2006. One-year rates of postoperative severe adverse events (endophthalmitis, suprachoroidal hemorrhage, retinal detachment) were determined for each cohort. Cox regression analyses determined the hazard of developing severe adverse events for each cohort with adjustment for demographic factors, ocular and medical conditions, and surgeon case-mix.
  
  
  METHODS
  Time period rates of development of severe postoperative adverse events.
  
  
  RESULTS
  Among the 221 594 individuals who underwent cataract surgery, 0.5% (1086) had at least 1 severe postoperative complication. After adjustment for confounders, individuals who underwent cataract surgery during 1994-1995 had a 21% increased hazard of being diagnosed with a severe postoperative complication (hazard ratio [HR] 1.21; 95% confidence interval [CI], 1.05-1.41) relative to individuals who underwent cataract surgery during 2005-2006. Those who underwent cataract surgery during 1999-2000 had a 20% increased hazard of experiencing a severe complication (HR 1.20; 95% CI, 1.04-1.39) relative to the 2005-2006 cohort. Risk factors associated with severe adverse events include a prior diagnosis of proliferative diabetic retinopathy (HR 1.62; 95% CI, 1.07-2.45) and cataract surgery combined with another intraocular surgical procedure on the same day (HR 2.51; 95% CI, 2.07-3.04). Individuals receiving surgery by surgeons with the case-mix least prone to developing a severe adverse event (HR 0.52; 95% CI, 0.44-0.62) had a 48% reduced hazard of a severe adverse event relative to recipients of cataract surgery performed by surgeons with the case-mix most prone to developing such outcomes.
  
  
  CONCLUSIONS
  Rates of sight-threatening adverse events after cataract surgery declined during 1994-2006. Future efforts should be directed to identifying ways to reduce severe adverse events in high-risk groups.
authors.affiliation: Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, Michigan 48105, USA. jdstein@med.umich.edu
authors.forename: Joshua D
authors.initials: JD
authors.lastname: Stein
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Grossman
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Mundy
authors.forename: Alan
authors.initials: A
authors.lastname: Sugar
authors.forename: Frank A
authors.initials: FA
authors.lastname: Sloan
mesh_terms: D000368:Aged; D002387:Cataract Extraction / Q000009:adverse effects*; D015897:Comorbidity; D016208:Databases, Factual; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D038801:International Classification of Diseases; D008297:Male; D016345:Medicare Part B / Q000706:statistics & numerical data*; D011183:Postoperative Complications; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D014481:United States