COVID-19 outcomes and vaccinations in Swedish solid organ transplant recipients 2020-2021: A nationwide multi-register comparative cohort study

Wednesday, August 28, 2024

1:30 PM - 1:45 PM CEST

Location: Conv Hall I D

Co-Author(s)

JS

John Søfteland, PhD

Researcher
The Transplant Institute, Sahlgrenska University Hospital, Gothenburg, Sweden, Sweden
Huiqi Li, PhD

Assoc. Prof.
School of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden, Sweden
JM

Jesper Magnusson

The Transplant Institute, Sahlgrenska University Hospital, Gothenburg, Sweden, Sweden
VF

Vanda Friman, PhD

Assoc. Prof.
Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden, Sweden
MG

Magnus Gisslén, PhD

Professor
Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden, Sweden
MF

Marie Felldin

The Transplant Institute, Sahlgrenska University Hospital, Gothenburg, Sweden, Sweden
AS

Andreas Schult

The Transplant Institute, Sahlgrenska University Hospital, Gothenburg, Sweden, Sweden
Kristjan Karason, MD, PhD

Senior Cardiologist
The Transplant Institute, Sahlgrenska University Hospital, Gothenburg, Sweden
Gothenburg, Sweden
SB

Seema Baid-Agrawal

The Transplant Institute, Sahlgrenska University Hospital, Gothenburg, Sweden, Sweden
CW

Carin Wallquist

Department of Nephrology, Skåne University Hospital, Malmö, Sweden, Sweden

Presenting Author(s)

Fredrik Nyberg, MD PhD

Professor of Register Epidemiology
School of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
School of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg
M�lndal, Sweden

Slides

Background: Increased COVID-19-related morbidity and mortality have been reported in solid organ transplant recipients (SOTR). Most studies are underpowered for rigorous analysis.

Objectives: To investigate infections, hospitalization, ICU care, and mortality from COVID-19 and pertinent vaccination status in Swedish SOTR 2020-2021.

Methods: Design and setting: This is a nationwide register-based cohort study encompassing all Swedish adults with a study period of 2020-2021. Data were obtained from national registers.
Exposure: SOTR were identified with ICD-10 codes (2015-2019) and immunosuppressant prescriptions (2019).
Outcomes: COVID-19-related outcomes included infection, hospitalization, ICU care, and mortality. The vaccination status was also described
Statistical analysis: Propensity score weighting was performed to achieve a good balance of potential confounders (age, sex, comorbidities, socioeconomic factors, and geography) between SOTR and non-SOTR groups. Cox regression was used to estimate the hazard ratio (HR) for each outcome, comparing SOTR to non-SOTR groups. Kaplan-Meier curve was used to visualize the survival pattern of the two groups over time.

Results: The study consisted of 10,372,033 individuals, including 9073 SOTRs. Among the COVID-19 infected, 47.3% of SOTRs and 19% of weighted non-SOTR individuals were hospitalized. ICU care was given to 8% of infected SOTRs and 2% of weighted comparators. The case fatality rate was 7.7% in SOTRs, 6.2% in the weighted comparison cohort, and 1.3% in the unweighted comparison cohort. SOTRs had an increased risk of contracting COVID-19 (HR=1.15 P< 0.001), being hospitalized (HR=2.89 P< 0.001), receiving ICU care (HR=4.59 P< 0.001) and death (HR=1.42 P< 0.001). Lung transplant recipients had substantially increased risk for hospitalization (HR=4.52 P< 0.001), ICU admission (HR=13.82, P< 0.001), and death (HR=3.15, P< 0.001). Infection curves were close between the two groups, while hospitalization and ICU care curves diverged. Mortality curves diverged in April 2021. 50% of the SOTR received two doses vaccination before late April 2021, while 50% of the weighted comparators before late June 2021.

Conclusions: SOTR had much higher morbidity and mortality than the general population during 2020-2021. Also compared with weighted comparators, SOTR had an increased risk of contracting COVID-19, being hospitalized, receiving ICU care, and dying. Lung transplant recipients had the worst outcomes. Excess mortality amongst SOTRs was concentrated in the second half of 2021. SOTR were vaccinated earlier than weighted comparators.