Endophthalmitis rates and risk factors following intraocular surgeries in the medicare population from 2016 to 2019

Aims To determine endophthalmitis rates and risk factors following intraocular surgeries in the Medicare population.Methods Retrospective, cross-sectional study from 2016 to 2019 in Medicare fee-for-service and Medicare Advantage beneficiaries. 100% Medicare claims were used to identify eyes that underwent intraocular surgery. Exclusion criteria included eyes that had intraocular surgery 42 days before or after and eyes in patients with a history of endophthalmitis within 12 months.Results 9 744 400 intraocular surgeries were performed among Medicare beneficiaries from 2016 to 2019. A 42-day postoperative endophthalmitis rate was 0.09%. Endophthalmitis rate by surgery type was 0.43% for corneal transplant, 0.36% for secondary intraocular lens (IOL), 0.24% for retina, 0.16% for glaucoma, 0.11% for cataract combined with other procedures and 0.08% for cataract surgeries alone. On multivariable analysis, the risk of endophthalmitis was increased for all intraocular surgery types when compared with cataract surgeries; adjusted OR (aOR) 5.30 (p<0.01) for corneal transplant, aOR 4.50 (p<0.01) for secondary IOL, aOR 3.00 (p<0.01) for retina, aOR 1.93 (p<0.01) for glaucoma, aOR 1.45 (p<0.01) for combined cataract surgeries. Increased risk of developing endophthalmitis was associated with older age (>= 85 vs 65-75 years: aOR 1.36; p<0.01), male sex (aOR 1.20; p<0.001) and greater Charlson Comorbidity Index (>= 7 vs 0: aOR 1.79; p<0.01).Conclusions Postoperative endophthalmitis rate after intraocular surgeries was 0.09% between 2016 and 2019 for Medicare beneficiaries. Endophthalmitis rates were highest for corneal transplant surgeries followed by secondary IOL surgeries and lowest for cataract surgeries. Older age, male gender and higher comorbidity index were associated with risk of endophthalmitis.