COVID-19 in SOT versus non-SOT.

Abstract

To the Editor: We read with great interest “Inpatient COVID-19 Outcomes in Solid Organ Transplant Recipients Compared to Non-Solid Organ Transplant Patients: A Retrospective Cohort” by Avery et al.1Avery RK, Chiang T-Y, Marr KA, et al. Inpatient COVID-19 outcomes in solid organ transplant recipients compared to non-solid organ transplant patients: a retrospective cohort. Am J Transplant. 2020. https://doi.org/10.1111/ajt.16431.Google Scholar The authors compared outcomes of 45 solid organ transplant recipients with 2427 non-transplant patients admitted with COVID-19 at Johns Hopkins medical system finding no differences in outcomes between the groups and concluded that SOT status does not portend adverse outcome from COVID-19. While this study is an important contribution to the literature, we have several concerns. A sample size of 45 for an SOT group is small. Important details like type of transplant and time since transplant which could have significant effect on mortality were not reported. The data are from a single hospital system in one region, so they may not be generalizable. The WHO severity score on admission was lower for the SOT group compared to the non-SOT group (3 vs. 4, p = .042) as well as oxygen requirement on admission was lower for the SOT group versus the non-SOT group (37.8% vs. 52.5%, p = .035). Impairment of oxygen on hospital admission was shown to be a stronger predictor than age and comorbidities for mortality in COVID-19.2Petrilli CM Jones SA Yang J et al.Factors associated with hospital admission and critical illness among 5279 people with coronavirus disease 2019 in New York City: prospective cohort study.BMJ. 2020; 369: m1966Crossref PubMed Scopus (1492) Google Scholar Our own data from a large multi-state healthcare system in the United States showed a similar finding of significant effect of initial oxygen categorization on mortality with odds ratio of up to 5.95 depending on degree of initial oxygen requirements.3Fisher AM, Schlauch D, Mulloy M, et al. Outcomes of COVID-19 in hospitalized solid organ transplant recipients compared to a matched cohort of non-transplant patients at a national healthcare system in the United States [published online ahead of print January 6, 2021]. Clin Transplant. doi:10.1111/ctr.14216Google Scholar The authors did do a propensity score analysis to adjust for this and state that there were no differences in mortality or length of stay between the groups with or without weighting. However, the data with updated numbers in each group after weighting, such analysis and odds ratios were not reported. Additionally, there were important differences in therapies between the groups. While utilization of methylprednisolone, hydrocortisone, and dexamethasone were under 20% and similar between the groups, prednisone use was more prevalent in the SOT group (as expected given its common use for maintenance immunosuppression) compared to the non-SOT group (60.0% vs. 4.6%, p < .001). This is pertinent as data from several randomized studies showed mortality benefit of corticosteroids in COVID-19. Also, tocilizumab usage was higher in the SOT group compared to the non-SOT group (13.3% vs. 3.6%, p = .006). Although tocilizumab is not proven to be beneficial for COVID-19 in randomized studies, in our clinical experience4Allam SR Dao A Madhrira MM et al.Interleukin-6 receptor antagonist therapy to treat SARS-CoV-2 driven inflammatory syndrome in a kidney transplant recipient.Transpl Infect Dis. 2020; 22: e13326Crossref PubMed Scopus (15) Google Scholar and others’,5Huang E Jordan SC. Tocilizumab for Covid-19 - the ongoing search for effective therapies.N Engl J Med. 2020; 383: 2387-2388Crossref PubMed Scopus (23) Google Scholar tocilizumab has potential benefit in a subset of patients with COVID-19. Lastly, transplant physicians typically take ownership and closely follow the care of their transplant recipients. This might have helped the SOT group sustain better outcomes given the data were from a single transplant hospital system. Given the small sample size of the SOT cohort in the study, only a few more fatalities could have drastically changed the results and conclusions of the study. A nationwide population study conducted in Italy that included the entirety of the COVID-19 cohort (general screening, outpatient, and inpatient settings) found that SOT recipients are at increased risk of infection (1.02% vs. 0.4%), of hospitalization (72.2% vs. 39.6%), and of mortality (30.6% vs. 15.4%) compared to the non-SOT group.6Trapani S, Masiero L, Puoti F, et al. Incidence and outcome of SARS-CoV-2 infection on solid organ transplantation recipients: a nationwide population-based study. Am J Transplant. 2020. https://doi.org/10.1111/ajt.16428.Google Scholar Taken together, we believe it is difficult to conclude that SOT recipients behave similar to the general population when infected with COVID-19. The authors of this manuscript have no conflicts of interest to disclose as described by the American Journal of Transplantation.