COVID-19 Research Updates
This Just In: Blog Post by AIM Chief Medical Officer Michelle Fiscus, MD
Many researchers worldwide are looking at the long-term impact of COVID-19 disease, as well as the possibility that COVID-19 vaccines may provide protection against more than acute disease.
Below is a quick synopsis of the findings of several recent studies.
mRNA COVID-19 Vaccines Improve Survival for Some Cancers
A study from researchers in Texas and Florida looked at electronic health records of patients of MD Anderson Cancer Center who were diagnosed with stage III or IV non-small cell lung cancer (NSCLC) or melanoma and found that receipts of an mRNA COVID-19 vaccine within 100 days of treatment with an immune checkpoint inhibitor (ICI) was associated with substantial improvements in overall survival compared to unvaccinated peers. The same effect was not seen with influenza vaccination. Researchers hypothesize that mRNA vaccines stimulate innate immune activation that, paired with ICI therapy, results in tumor regression and improved survival.
Diagnosis of Long COVID in Medicare Beneficiaries was 39% Lower in Individuals Who Received Four or More COVID-19 Vaccine Doses
This study out of Rhode Island looked at Medicare Part A-B claims of 3,588,671 Medicare beneficiaries aged>66 years and diagnosed with COVID-19 between October 2021 and March 2023. Approximately 4% of patients were diagnosed with long COVID within one year of infection. A greater number of COVID-19 doses was associated with a graduated reduction in long COVID diagnosis, with individuals who had received four or more COVID-19 vaccines having a 39% lower adjusted rate of long COVID relative to unvaccinated individuals. Unvaccinated individuals showed a 59% greater relative risk and a 1.58% greater absolute risk of a long COVID diagnosis compared to individuals with four or more vaccine doses. (Note the limitation that vaccines not billed to Medicare could not be counted; therefore, some individuals categorized as “unvaccinated” may have been vaccinated.)
COVID-19 Vaccination Reduced Risk of Death from COVID-19 and Reduced All-cause Mortality in France
This study from France looked at 22.7 million vaccinated and 5.9 million unvaccinated French adults ages 18-59 years. Vaccinated individuals received a first mRNA COVID-19 vaccine dose between May 1 and October 31, 2021, and showed a 74% lower risk of death from severe COVID-19 disease and a 25% lower risk of all-cause mortality compared to unvaccinated adults ages 18-59 years. Authors concluded “A causal link between mRNA vaccination and excess long-term mortality appears highly unlikely.”
COVID-19 Vaccination During Pregnancy Reduces Severe COVID-19 Disease During Pregnancy and Reduces the Chance of Premature Delivery
This study out of Canada looked at nearly 20,000 individuals diagnosed with COVID-19 during pregnancy and showed that COVID-19 vaccination prior to or during pregnancy was associated with a lower risk of hospitalization, critical care unit admission, and preterm birth after controlling for co-morbid conditions.