At 11:00 am ET today (November 1, 2021), the results will be released for research that studied Incidence of blood clot in brain after Johnson & Johnson/Janssen COVID-19 vaccination.
What The Study Did: Resarchers compared post-Ad26.COV2.S (Johnson & Johnson/Janssen) vaccination cerebral venous sinus thrombosis (CVST, a blood clot in the brain) rates with prepandemic rates to estimate postvaccination CVST risk. The rate of this rare adverse effect must be considered in the context of the effectiveness of the vaccine in preventing COVID-19.
Authors: Aneel A. Ashrani, M.D., M.S., of the Mayo Clinic in Rochester, Minnesota, is the corresponding author.
Link: JAMA Internal Medicine
The study found a “significantly higher” brain blood clot (cerebral venous sinus thrombosis / CVST) incidence rate in people after vaccination with the Johnson & Johnson COVID-19 vaccine. The highest risk was in women between the ages of 30 and 49, with most CVST events happening within 15 days of vaccination.
Although this is a serious side effect, the authors caution that “the higher rate of this rare adverse effect must be considered in the context of the effectiveness of the vaccine in preventing COVID-19.”
Reference: “Age- and Sex-Specific Incidence of Cerebral Venous Sinus Thrombosis Associated With Ad26.COV2.S COVID-19 Vaccination” by Aneel A. Ashrani, MD, MS; Daniel J. Crusan, BS; Tanya Petterson, MS; Kent Bailey, PhD and John A. Heit, MD, 1 November 2021, JAMA Internal Medicine.