Severe Adverse Events after Cataract Surgery Among Medicare Beneficiaries

Abstract

Purpose To determine rates and risk factors associated with severe post-operative complications following cataract surgery and whether they have been changing over the past decade. Design Retrospective longitudinal cohort study Participants 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 1994-5, 1999–2000, or 2005-6. One year rates of post-operative 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. Main Outcome Measures Time period rates of development of severe post-operative adverse events. Results Among the 221,594 individuals who underwent cataract surgery, 0.5% (1,086) had at least one severe post-operative complication. After adjustment for confounders, individuals who underwent cataract surgery during 1994-5 had a 21% increased hazard of being diagnosed with a severe post-operative complication (Hazard Ratio (HR): 1.21; [95% Confidence Interval (CI): 1.05–1.41]) relative to individuals who underwent cataract surgery during 2005-6. 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 2005-6 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. Conclusion Rates of sight-threatening adverse events following cataract surgery declined during 1994–2006. Future efforts should be directed to identifying ways to reduce severe adverse events in high-risk groups.

Predictive Modeling of Risk Factors and Complications of Cataract Surgery

“…Many existing studies of predictors for cataract surgery complications have evaluated risk factors for aggregated complications. [16, 21, 26, 34, 35] Our findings were consistent with the literature describing risk factors for any postoperative complication, including: complex cataract surgery, any intraoperative complication, black race and previous eye surgery (including keratorefractive surgery). [17, 26]…”

“…[39–43] Postoperative endophthalmitis and retinal tear/detachment are also well-studied[16, 28, 44–49]—and our analysis also found complex cataract surgery to be associated with higher risk for endophthalmitis—however, other post-operative complications have been less extensively described in the literature. [17, 35, 50–53]…”

“…Prior studies have demonstrated that diabetic retinopathy increases the risk of poor visual acuity outcomes and surgical complications. [14–16, 25] However, our study indicates a significant association between systemic diabetes mellitus itself (irrespective of diabetic retinopathy) and a number of complications, including posterior capsule tear, endophthalmitis, and cystoid macular edema. Additionally, while young age (<60 years old) has previously been linked to endophthalmitis[28] and retinal detachment/tear,[27, 48] our work found it as a risk factor for many other intra- and post-operative complications.…”

“…any intraoperative complication). [12, 16, 17] Studies exploring specific outcomes have tended to focus either on the relationship between preoperative risk factors and intraoperative complications,[10, 18–25] or on the relationship between intraoperative and postoperative complications. [26–28] Few studies have examined relationships between preoperative risk factors and postoperative complications, or explored the combined effects of a large number of risk factors and complications simultaneously.…”

Characteristics of Endophthalmitis after Cataract Surgery in the United States Medicare Population

“…Endophthalmitis remains a rare but serious complication of cataract surgery. Previous studies analyzing Medicare claims data report an incidence of 1.1 to 1.33 endophthalmitis cases per 1000 surgeries in 2003 and 2004, 1 1.6 cases per 1000 surgeries from 1994 through 2006, 2 and 0.63 to 1.27 cases per 1000 surgeries from 2006 through 2011, 3 depending on how strictly endophthalmitis is defined. The Endophthalmitis Vitrectomy Study (EVS) is the only clinical trial to have evaluated the effects of vitrectomy and systemic antibiotics on visual outcomes among cases of endophthalmitis occurring after cataract surgery.…”