Mortality and Readmissions of Solid-Organs Transplant Recipients Hospitalized Due to COVID-19 Infection with the Omicron Variant: A Matched Cohort Study.

Abstract

Background: Solid organ transplant (SOT) recipients represent a particularly vulnerable group due to their reliance on immunosuppressive therapies. Previous studies indicated a mortality rate of 20%-30% among SOT recipients with coronavirus disease 2019 (COVID-19). With the advent of the Omicron variant in November 2021, characterized by milder symptoms and lower mortality rates in the general population, safety measures relaxed, potentially impacting vulnerable populations like SOT recipients.

Objectives: To investigate mortality and morbidity among hospitalized SOT recipients with COVID-19 infection during the Omicron wave.

Methods: A retrospective, propensity-matched cohort study conducted at the Rabin Medical Center, Israel, spanned from November 2021 to June 2023. Adult SOT recipients hospitalized with COVID-19 were compared to matched controls.

Results: Among 139 hospitalized SOT recipients and 209 controls, SOT recipients hospitalized with COVID-19 displayed higher in-hospital mortality (19% vs. 11%) and 90-day all-cause mortality (30% vs. 17%). In addition, the 90-day readmission rate was significantly higher among SOT recipients (43% vs. 31%). Multivariable analysis confirmed these trends, with SOT recipients exhibiting increased risk for mortality, readmission, invasive ventilation, and intensive care unit admission.

Conclusions: The heightened vulnerability of hospitalized SOT recipients during the Omicron wave was characterized by higher mortality and readmission rates compared to matched controls. Despite the perceived milder nature of the Omicron variant, SOT recipients remain disproportionately affected. Continued vigilance and targeted interventions are necessary for this population including vaccinations and adherence to preventive measures. Investigating this population's outcomes through the changing COVID-19 variants is still warranted.