Longitudinal Outcomes of COVID-19 in Solid Organ Transplant Recipients from 2020 to 2023.

Data regarding COVID-19 outcomes in solid organ transplant recipients(SOTr) across SARS-CoV-2 waves, including the impact of different measures, is lacking. This cohort study, conducted from March 2020-May 2023 in Toronto, Canada, aimed to analyze COVID-19 outcomes in 1,975 SOTr across various SARS-CoV-2 waves and assess the impact of preventive and treatment measures. The primary outcome was severe COVID-19, defined as requiring supplemental oxygen, with secondary outcomes including hospitalization, length of stay, ICU admission, and 30-day and 1-year all-cause mortality. SARS-CoV-2 waves were categorized as Wildtype/Alpha/Delta(318 cases, 16.1%), Omicron-BA.1(268, 26.2%), Omicron-BA.2(268, 13.6%), Omicron-BA.5(561, 28.4%), Omicron-BQ.1.1(188, 9.5%), and Omicron-XBB.1.5(123, 6.2%). Severe COVID-19 rate was highest during the Wildtype/Alpha/Delta wave(44.6%), and lower in Omicron waves(5.7-16.1%). Lung transplantation was associated with severe COVID-19(OR:4.62, 95%CI:2.71-7.89), along with rituximab treatment(OR:4.24, 95%CI:1.04-17.3), long-term corticosteroid use(OR:3.11, 95%CI:1.46-6.62), older age(OR: 1.51, 95%CI:1.30-1.76), chronic lung disease(OR:2.11, 95%CI:1.36-3.30), chronic kidney disease(OR:2.18, 95%CI:1.17-4.07), and diabetes(OR:1.97, 95%CI:1.37-2.83). Early treatment and ≥3 vaccine doses were associated with reduced severity(OR: 0.29, 95%CI:0.19-0.46, and 0.35, 95%CI:0.21-0.60, respectively). Tixagevimab/cilgavimab and bivalent boosters did not show a significant impact. The study concludes that COVID-19 severity decreased across different variants in SOTr. Lung transplantation was associated with worse outcomes and may benefit more from preventive and early therapeutic interventions.