心筋炎はワクチンよりもCOVID-19の方が7倍起こりやすい(Myocarditis seven times more likely with COVID-19 than vaccines)

2022-10-13

2022-10-12 ペンシルベニア州立大学(PennState)

ペンシルベニア州立医科大学の科学者による最近の研究によると、心筋炎(または心筋の炎症)を発症するリスクは、COVID-19ワクチンを接種した場合よりもCOVID-19感染症の方が7倍高いことが明らかになった。
研究チームは、コロナウイルスに感染した場合とCOVID-19ワクチン接種後に炎症を起こした場合の心筋炎発症リスクについて、これまでで最大の調査を実施した。研究者らは、COVID-19のワクチン接種患者と非接種患者を、ウイルスを保有していない患者と比較した。その結果、ワクチン接種の有無にかかわらず、COVID-19患者では、ウイルスに感染していない人に比べて心筋炎のリスクが15倍高いことがわかった。
次に、ワクチンを接種した人と接種していない人の心筋炎発症率を別々に比較した。その結果、COVID-19のワクチンを接種した人の心筋炎の発症率は、ワクチンを接種していない人の2倍程度に過ぎないことがわかった。
COVID-19感染と関連するワクチンは、どちらも心筋炎のリスクをもたらす。しかし、COVID-19感染によって引き起こされる心臓の炎症の相対リスクは、ワクチンによってもたらされるリスクよりもかなり大きい。

<関連情報>

SARS-CoV-2感染における心筋炎とCOVID-19ワクチン接種の比較:システマティックレビューとメタアナリシス
Myocarditis in SARS-CoV-2 infection vs. COVID-19 vaccination: A systematic review and meta-analysis

Navya Voleti, Surya Prakash Reddy and Paddy Ssentongo
Frontiers Published:29 August 2022
DOI:https://doi.org/10.3389/fcvm.2022.951314

Background: This study aimed to compare the incidence of myocarditis in COVID-19 vaccines and in severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) infection groups.

Methods: Electronic databases (MEDLINE, Scopus, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and the WHO Global Literature on Coronavirus Disease) and trial registries were searched up to May 2022, for randomized controlled trials and observational cohort studies reporting the risk of myocarditis associated with the COVID-19 vaccines and the risk associated with SARS-CoV-2 infection. We estimated the effect of COVID-19 infection and vaccines on rates of myocarditis by random-effects meta-analyses using the generic inverse variance method. Meta-regression analyses were conducted to assess the effect of sex and age on the incidence of myocarditis.

Results: We identified 22 eligible studies consisting of 55.5 million vaccinated cohorts and 2.5 million in the infection cohort. The median age was 49 years (interquartile range (IQR): 38–56), and 49% (IQR: 43 to 52%) were men. Of patients diagnosed with myocarditis (in both vaccination and COVID-19 cohort) 1.07% were hospitalized and 0.015% died. The relative risk (RR) for myocarditis was more than seven times higher in the infection group than in the vaccination group [RR: 15 (95% CI: 11.09–19.81, infection group] and RR: 2 (95% CI: 1.44-2.65, vaccine group). Of patients who developed myocarditis after receiving the vaccine or having the infection, 61% (IQR: 39–87%) were men. Meta-regression analysis indicated that men and younger populations had a higher risk of myocarditis. A slow decline in the rates of myocarditis was observed as a function of time from vaccination. The risk of bias was low.

Conclusion: In this systematic review and meta-analysis, we found that the risk of myocarditis is more than seven fold higher in persons who were infected with the SARS-CoV-2 than in those who received the vaccine. These findings support the continued use of mRNA COVID-19 vaccines among all eligible persons per CDC and WHO recommendations.