Assessment of myocarditis and pericarditis in immunocompromised people after COVID-19 mRNA vaccination

A team of researchers recently compared reporting rates of myocarditis and pericarditis between immunocompromised patients and the general population to investigate a possible association between coronavirus disease 2019 (COVID-19) mRNA vaccines and these diseases, and published their results in the medRxiv * preprint Server.

Study: Systematic review of spontaneous reports of myocarditis and pericarditis in transplant recipients and immunocompromised patients after COVID-19 mRNA vaccination. Image source: Halfpoint / Shutterstock

COVID-19 has remained a major health problem worldwide since it was first reported in Wuhan, China, in late 2019. The most important response to the effective regulation and containment of pandemic-related health crises was the development of various vaccines against the severe acute respiratory disease syndrome coronavirus 2 (SARS-CoV-2). To date, several vaccines such as Pfizer and Moderna mRNA vaccines and viral vector-borne vaccines such as Oxford’s ChAdOX1 and Sputnik V. have been approved by the World Health Organization (WHO) for emergency use.

COVID-19 mRNA vaccines are the first nucleic acid-based vaccines to be approved for use. In contrast to traditional vaccines, mRNA vaccines can be modified for use against new variants if necessary, for example during the current global surge in COVID-19 cases, which is dominated by the rapid transmission of the SARS-CoV-2 omicron variant . However, with the widespread adoption of booster doses in several countries, more research is needed to identify the potential side effects of mRNA vaccines.

The study

Increases in myocarditis, pericarditis and myopericarditis have been noted in Europe and the United States (USA) following the administration of SARS-CoV-2 mRNA vaccines. In Europe, about 26-57 cases per million were reported within the first week of starting vaccination, and up to 40.6 cases per million in the US after the second dose was given. Inflammation of the myocardium and pericardium causes myocarditis and pericarditis, which leads to chest pain, shortness of breath, heart failure, palpitations, and irregular heartbeat.

In the present study, the researchers examined the possible connection between the mRNA vaccines and the diseases mentioned in a systematic review. The researchers used data from EudraVigilance (EU / EEA) and the Vaccine Adverse Event Reporting System (US) for analysis.

results

Of 5681 patients who reported either myocarditis or pericarditis or both in the European Union (EU) / European Economic Area (EEA), there were 49 immunocompromised patients. Two cases reported both myocarditis and pericarditis, while 30 and 21 were cases of pericarditis and myocarditis, respectively; 38 cases were classified as serious (defined as prolonged hospital stay or life-threatening or fatal outcome).

Cancer drugs were the most common concomitant medication. Over 57% of the reported cases were men, while 61.2% of the cases were in patients in the 18- to 64-year-old age group. While 156 of the 5681 cases reported a death, no death was recorded in the immunocompromised patients.

In the United States, more than 3,000 cases of myocarditis or pericarditis have been recorded after administration of the mRNA vaccine, including 57 cases (1.86%) in immunocompromised patients. More than 52% of these events were seen in men, and more than half of them were under 60 years of age. These events were predominantly observed after the administration of the second dose of the mRNA vaccine and approximately 70% of these cases were observed within 14 days of vaccination. Over 68% of the cases were classified as serious and one fatality was recorded in the US eight days after the first vaccination in a patient receiving cancer therapy. Although the cause of death was not stated, the autopsy revealed a systemic inflammatory response. The team observed a slight increase (around 5%) in severe cases in the immunocompromised category compared to the general population.

limitations

The study relied on publicly available data that may not lack comprehensive information due to inadequate reporting and / or incorrect classification of immunosuppressed individuals as immunocompetent. In addition, due to a lack of data, the researchers neither reported the incidence rates of the exposed population, nor did they include a non-exposed comparison group for analysis.

Conclusions

From the observations made in this study it was found that there was little evidence that conclusively showed differences in the frequency of myocarditis and pericarditis cases between immunocompromised individuals and the general population. Additionally, cases were more pronounced in the US, being reported within 14 days of the second dose, while no particular trends were observed based on demographics or gender.

The study found that mRNA vaccines trigger a T-cell-mediated immune response, specifically the CD4 + T cells, and post-vaccination myocarditis or pericarditis could be due to the activity of CD4 + T cells. It is also known that immunocompromised people have decreased B and T lymphocyte activity, which could also increase the risk of side effects after mRNA vaccination.

In summary, the present study did not conclusively correlate the incidence of myocarditis or pericarditis with mRNA vaccination, as these events are rarely observed after vaccination. Further research is needed to characterize the prognosis for these events following administration of an mRNA vaccine.

*Important NOTE

medRxiv publishes preliminary scientific reports that have not been peer-reviewed and therefore should not be considered conclusive, that guide clinical practice / health-related behavior or should be treated as established information