Post-acute sequelae following Omicron COVID-19 in transplant recipients: a population-based cohort study

Abstract

Population-based studies evaluating long-COVID-19 prevalence in transplant recipients are limited. We examined risk of new-incident multi-systemic sequelae post-SARS-CoV-2 Omicron infection in a retrospective population-based cohort of transplant recipients, versus test-negatives. National COVID-19/healthcare-claims databases were utilised to construct cohorts of all Singaporean adult transplant recipients infected during Omicron-predominance (1^st Jan-31^st Dec 2022), and contemporaneous test-negatives. Competing risks regression (death as a competing risk), with overlap weights applied, was utilised to estimate risks of new-incident diagnoses/symptoms 31-300 days post-SARS-CoV-2 infection in transplant recipients, versus test-negatives. 1,890 SARS-CoV-2 infected transplant recipients and 1,482 test-negatives were included. 88.7% were boosted. Overall risks of post-acute sequelae were not significantly increased in SARS-CoV-2-infected transplant recipients, versus test-negatives (any post-acute diagnosis: adjusted-hazards-ratio, aHR=1.35[95%CI=0.74-2.45]; any post-acute symptom: aHR=1.06[95%CI=0.52-2.17]). However, increased risk of post-acute autoimmune (aHR=5.34[95%CI=1.03-27.62])/neurological sequelae (aHR=3.06[95%CI=1.23-7.61]) were observed in SARS-CoV-2-infected transplant recipients versus test-negatives; though excess-burden was modest (autoimmune: EB-per-1000-individuals=5.58[95%CI=-4.49-15.65]; neurological: EB-per-1000-individuals=19.82[95%CI=-4.33-43.96]). Risks of post-acute neurological/autoimmune sequelae remained elevated in untreated COVID-19 cases versus test-negatives but did not significantly differ in treated COVID-19 cases versus test-negatives. We conclude that overall risk of post-acute sequelae was not significantly elevated in a highly-vaccinated/boosted cohort of Omicron SARS-CoV-2-infected transplant recipients, versus test-negatives. COVID-19 vaccination/boosting remains important during endemicity.

Keywords: COVID-19; SARS-CoV-2; long COVID; post-acute sequelae of SARS-CoV-2 (PASC); transplant; vaccination.