Breakthrough Coronavirus Associated Infectious Disease 2019 After Vaccination Among Kidney Transplant Recipients

Kidney transplant recipients remain susceptible to severe infectious disease such as the coronavirus associated infectious disease 2019 (COVID-19). Vaccination remains an important step in prevention, but data is needed to support the efficacy in this high-risk population. We sought to evaluate risk factors for breakthrough COVID-19 infection following vaccination among a single US state's resident with kidney transplant (KT).

Patients with a KT diagnosis prior to the COVID-19 pandemic period from 2019 to 2022 were compared to individuals without KT from a US statewide health registry for South Carolina. Propensity score matching used to match KT and non-KT recipients. Risk of breakthrough infections compared using Cox proportional hazards models. Outcomes (hospitalization and death) associated with breakthrough infection were similarly evaluated.

After propensity score matching, 1270 KT and 2540 non-KT remained for analysis. Baseline covariates were well matched. Hazard ratio (HR) and 95% confidence interval (95%CI) for breakthrough COVID-19 infection for KT was 2.61 (1.94, 3.53; p < .001) versus non-KT. Booster vaccination was associated with lower risk for breakthrough vaccination (OR: 0.19, 95% CI: 0.11, 0.27, p < .001). KT patients with breakthrough COVID-19 infection had an odds ratio (OR) of 18 (95% CI 6.5, 61.1; p < .001) for hospitalization and OR 10.2 (95% CI: 2.65, 53.4; p = .002) for death versus non-KT.

Kidney transplant recipients remain at high risk for breakthrough COVID-19 infection as compared to non-kidney transplant recipients. Vaccination with mRNA-based vaccines and receipt of booster doses appear protective against infection and adverse outcomes.