A new study has found there may be a slightly increased risk of strokes in adults age 85 or older if they receive vaccines for COVID-19 and influenza at the same time.
The risk identified in the study, which was supported by the U.S. Food and Drug Administration, appears to be very low, with only three reported strokes for every 100,000 doses administered. The data also shows the risk of stroke could be primarily driven by the high-dose flu vaccine alone.
Even if the links are confirmed, the benefits of vaccination still far outweigh the risks, especially in older adults, experts said in the study.
Flu and COVID-19 themselves both raise the risk of stroke without vaccination, researchers said, and guidance for receiving the vaccines should not be changed.
The FDA looked at data from Medicare claims of more than 5.3 million adults aged 65 or older who received a bivalent COVID-19 vaccine made by Pfizer or Moderna as a basis for the study. There were no increased risks of strokes in the overall group.
The observational analysis was posted online last week but has not been published by a scientific journal yet – meaning the report has not been certified by peer review and should not be relied on to guide clinical practice at this time – and it only shows associations, not cause and effect.
It’s not the first time a link between strokes and the mRNA COVID-19 vaccine has been identified. Similar studies have been published by the Frontiers in Neurology on the National Library of Medicine database, but the Center for Disease Control and Prevention said their vaccine safety monitoring systems are designed to be sensitive, and detection of potential safety signals simply means their process is working.
Taylor O'Bier
