By Andrea S. Blevins Primeau, PhD, MBA
Hematology Advisor
Vaccination for SARS-CoV-2 infection reduced the risk of COVID-19 mortality and hospitalization in patients with myeloproliferative neoplasms (MPNs), according to the results of a study that was presented at the EHA 2022 Hybrid Congress.
Prior to this study, there were “no robust data on characterizing the clinical outcomes of patients with MPN and COVID-19 in the United States,” the authors reported.
The single-center, retrospective, observational cohort study evaluated data from 388 patients with MPN and COVID-19 between April 2020 and December 2021. Of these patients, 53 had positive SARS-CoV-2 test results by RT-PCR.
“To date, this is the largest cohort of MPN patients with COVID-19 infection in the US, which accounts for 14% of the MPN patients in our center,” the authors reported.
The median age at baseline was 59 years, 51% of patients were men, and 46% had a body mass index (BMI) of 30 kg/m2 or higher. The cohort comprised 55% of patients with myelofibrosis (MF), 28% with polycythemia vera (PV), and 17% with essential thrombocythemia (ET). The most common comorbidities were hypertension, present in 60% of patients, and diabetes, which was present in 19%.
Hospitalization was required for 47% of patients; of these patients, 68% required supplemental oxygen. Patients with MF had the highest rates of hospitalization, at 68%, compared with patients with PV or ET. The median length of stay was 8 days.
There were 49% of patients who had been vaccinated. Infection after the first dose of the vaccine occurred in 23% of patients.
Vaccination against SARS-CoV-2 was associated with better outcomes. Hospitalization rates were lower among patients who were immunized, at 28%, compared with 72% for patients who were not immunized.
Of the 9 patients who died, all but 1 were unvaccinated. The median overall survival of vaccinated patients was not reached, compared with 19.9 months among patients who were unvaccinated.
Overall, the case fatality rate of SARS-CoV-2 infection was 17%. The median overall survival was not reached during a median follow-up of 14.8 months.
The authors concluded that SARS-CoV-2 vaccination significantly decreases the risk of mortality and hospitalization in patients with MPN. In addition, they added that BMI 30 kg/m2 or higher appears to be an important risk factor.