COVID-19 Outcomes and Vaccinations in Swedish Solid Organ Transplant Recipients 2020-2021: A Nationwide Multi-Register Comparative Cohort Study

Viruses. 2024 Feb 8;16(2):271. doi: 10.3390/v16020271.


Increased COVID-19-related morbidity and mortality have been reported in solid organ transplant recipients (SOTRs). Most studies are underpowered for rigorous matching. We report infections, hospitalization, ICU care, mortality from COVID-19, and pertinent vaccination data in Swedish SOTRs 2020-2021. We conducted a nationwide cohort study, encompassing all Swedish residents. SOTRs were identified with ICD-10 codes and immunosuppressant prescriptions. Comparison cohorts were weighted based on a propensity score built from potential confounders (age, sex, comorbidities, socioeconomic factors, and geography), which achieved a good balance between SOTRs and non-SOTR groups. We included 10,372,033 individuals, including 9073 SOTRs. Of the SARS-CoV-2 infected, 47.3% of SOTRs and 19% of weighted comparator 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 dying (HR = 1.42 p < 0.001). SOTRs had much higher morbidity and mortality than the general population during 2020-2021. Also compared with weighted comparators, SOTRs had an increased risk of contracting COVID-19, being hospitalized, receiving ICU care, and dying. In Sweden, SOTRs were vaccinated earlier than weighted comparators. Lung transplant recipients had the worst outcomes. Excess mortality among SOTRs was concentrated in the second half of 2021.

Keywords: COVID-19; immunosuppression; solid organ transplant recipients; transplantation; vaccines.

MeSH terms

  • COVID-19* / epidemiology
  • COVID-19* / etiology
  • COVID-19* / prevention & control
  • Cohort Studies
  • Humans
  • Organ Transplantation* / adverse effects
  • SARS-CoV-2
  • Sweden / epidemiology
  • Transplant Recipients
  • Vaccination

Grants and funding

The study was financed by grants from Njurstiftelsen, Njurfonden (F2021-0075), The Healthcare Board, Region Västra Götaland (Hälso- och sjukvårdsstyrelsen) (VGFOUREG-941182, 969603), the SciLifeLab National COVID-19 Research Program, financed by the Knut and Alice Wallenberg Foundation (KAW 2020-0015, 2020.0182, 2020.0241, 2021-0010/VC2021.0018 and 2020.0299/VC 2022.0008), Göteborgs läkaresällskap (960901), and by the Swedish state, under an agreement between the Swedish government and the county councils (ALFGBG-679621, ALFGBG-717531, ALFGBG-938453, ALFGBG-942813, ALFGBG-965885, ALFGBG-971130, ALFGBG-978954), and by the Swedish Research Council (2021-05045, 2021-05405 and 2021-05450), Swedish Heart Lung Foundation (2021-0030 and 2021-0581) and a joint grant from Forte (Swedish Research Council for Health, Working Life and Welfare) and FORMAS (Forskningsrådet för miljö, areella näringar och samhällsbyggande), grant 2020-02828.