Corneal Transplant Rejection Postvaccination Among Medicare Beneficiaries.

PURPOSE:The purpose of this study was to describe the incidence of corneal graft rejection after COVID and influenza vaccination. METHODS:Patients 65 years or older undergoing penetrating keratoplasty or endothelial keratoplasty any time between 2016 and 2021 followed by COVID or influenza vaccination in 2021 among the 100% Medicare Fee-For-Service database were included. Demographic and ocular history characteristics of patients with (cases) and without graft rejection (controls) were compared using the χ2 test. RESULTS:After COVID (n = 31,398) and influenza (n = 24,290) vaccination, 0.45% (n = 140) and 0.17% (n = 41) patients developed rejection within 90 days, respectively. There was no difference in the rate of graft rejection within 90 days relative to 90 to 180 days after vaccination after both COVID (90 days: 0.45% vs. 180 days: 0.61%, P = 0.37) and influenza (90 days: 0.17% vs. 180 days: 0.29%, P = 0.11) vaccines. For COVID vaccination, patients who underwent penetrating keratoplasty (n = 51, 0.97%; vs. endothelial keratoplasty = 89; 0.34%, P < 0.001), history of rejection up to 1 year before vaccination (n = 13; 1.30% vs. no history = 127, 0.42%; P < 0.001), and having an ocular comorbidity (n = 110, 0.54% vs. no ocular comorbidity = 30, 0.27%; P = 0.001) had higher rates of graft rejections, and most rejections were after 1 year postkeratoplasty (87.14%, n = 122). CONCLUSIONS:The incidence of graft rejection postvaccination is low compared with the overall rates of rejection in the published literature. Most post-COVID vaccination graft rejections were after 1 year postkeratoplasty when corticosteroids are expected to have been tapered to lower doses. Surgeons may counsel patients regarding graft rejection symptoms, but overall low rates may not warrant pretreatment in low-risk keratoplasty patients.