Lung Transplant Recipients Fared Better With Omicron vs Other COVID-19 Variants

Among patients who had received lung transplants and later became infected with COVID-19, those infected with the Omicron variant of SARS-CoV-2 had lower rates of 90-day mortality, severe disease, and hospitalization than those infected with earlier variants. These were among results of a retrospective analysis reported in a research letter published in Annals of The American Thoracic Society.

By mid-December 2021, the Omicron variant was the predominant source of COVID-19 infections in New York City. Researchers with the Lung Transplant Program at Columbia University analyzed clinical and mortality outcomes among patients who had received lung transplants and had confirmed SARS-CoV-2 between December 19, 2021, and January 31, 2022, and compared this data with that of patients who had received lung transplants and were infected with COVID-19 during the first and second waves of the pandemic — between March 19, 2020, and May 29, 2020, and November 1, 2020, to February 28, 2021, respectively.

Cases were identified through electronic health records and patient reported information. Overall, 98 patients who had received lung transplants tested positive during the Omicron surge while 32 and 47 patients tested positive during the first and second waves of COVID-19 infection, respectively. Among the patients infected during the Omicron surge, 50% were female (vs 16% and 25% during the first and second waves, respectively) and the median patient age was 58 years (vs a median age of 65 years for both the first and second wave cohorts).

Within the Omicron cohort, 14% of patients had been previously infected with COVID-19; 11% were unvaccinated; 89% had received 2 doses of the mRNA COVID-19 vaccines or 1 dose of a viral vector vaccine; and 72% had received a booster. Notably, more than 70% of the entire Omicron cohort contracted COVID-19 after receiving a COVID-19 vaccine booster, a finding that lends “support to the observed suboptimal vaccine immunogenicity response to the Omicron variant among immunocompromised patients described in early studies,” said authors of the research letter.

In comparing outcomes among the Omicron, first wave, and second wave cohorts, the investigators found that: 90-day mortality rates were 12%, 34%, and 17%, respectively; severe disease rates were 14%, 41%, and 28%, respectively; hospitalization rates were 39%, 84%, and 66% respectively; and mechanical ventilation rates were 7%, 31%, and 15%, respectively.

Study authors also noted that in the Omicron cohort: (1) among the 31% of patients who required supplemental oxygen, 91% received dexamethasone or equivalent corticosteroids; and (2) among the 60% of patients with mild disease, 78% received monoclonal antibody or oral antiviral medications.

This research was limited by the unequal number of patients in the study cohorts and by the retrospective nature of the analysis.

The research letter authors concluded that “despite major improvements in outcomes in the last 2 years, COVID-19 continues to be associated with significant mortality among [lung transplant recipients].” The authors further noted that “Continued research for more effective pre- and post- exposure prophylactic therapies is also needed for this population.”

Reference

Hum J, Laothamatas K, Scheffert J, et al. Impact of Omicron on lung transplant recipients: a third COVID-19 surge with different outcomes. Ann Am Thorac Soc. Published online September 1, 2022. doi:10.1513/AnnalsATS.202205-452RL