Myocarditis and pericarditis associated with SARS-CoV-2 vaccines

Together with colleagues across Europe we have recently published our work entitled “Myocarditis and pericarditis associated with SARS-CoV-2 vaccines: a population-based descriptive cohort and a nested self-controlled risk interval study using electronic health care data from four European countries” in Frontiers in Pharmacology.

In this multi-country study that used data from four countries, the researchers studied first myo-/pericarditis diagnosis after exposure to first and second dose of Pfizer, AstraZeneca, Moderna, and Janssen COVID-19 vaccines. The study followed the design of a population-based cohort study with nested self-controlled risk interval (SCRI). Individuals were followed from 01/01/2020 until end of data availability (31/12/2021 latest).

Over 35 million individuals (49·2% women, median age 39–49 years) were included, of which 57·4% received at least one COVID-19 vaccine dose. Baseline incidence of myocarditis was low. Myocarditis IRRs were elevated after vaccination in those aged < 30 years, after both Pfizer vaccine doses (IRR = 3·3, 95%CI 1·2-9.4; 7·8, 95%CI 2·6-23·5, respectively) and Moderna vaccine dose 2 (IRR = 6·1, 95%CI 1·1-33·5). An effect of AstraZeneca vaccine dose 2 could not be excluded (IRR = 2·42, 95%CI 0·96-6·07). Pericarditis was not associated with vaccination. Important to note is that the absolute incidence of myocarditis remains low.

Please read the full article to check more detailed methodology and results.