Abstract
Myocarditis is a serious, sometimes fatal cardiac complication of COVID-19 infection. In this study, we describe demographic trends of myocarditis-related deaths before and during the COVID-19 pandemic and highlight any disparities in population characteristics of patients at risk.
A trend-level analysis was performed using death certificate data for myocarditis-related mortality as identified by International Classification of Diseases-10 ([ICD-10] codes I40 and I51.4) from the Centers for Disease Control (CDC) Wide-ranging ONline Data for Epidemiologic Research (WONDER) database. We compared the periods before (1999-2019) and during (2020-2021) the COVID-19 pandemic. Annual percentage changes (APCs) and age-adjusted mortality rates (AAMRs) per 100,000 persons were calculated and stratified by year, age, gender, race/ethnicity, and region.
Between 1999 and 2021, there were 33,750 myocarditis-related deaths. From 1999 to 2019, there was a consistent decline in mortality, with AAMR decreasing from 0.62 in 1999 to 0.35 in 2019 (APC: -2.42 [-3.19 to -1.95], Figure 1). However, this trend reversed with a sharp increase in AAMR during the time of the COVID-19 pandemic, increasing to 0.49 in 2020 and 0.50 in 2021 (APC: 20.32 [4.11 to 29.50]). Men had consistently higher AAMR before (AAMR men: 0.54 vs. women: 0.39) and during the pandemic (AAMR men: 0.58 vs. women: 0.42). Non-Hispanic (NH) Blacks had a consistently higher AAMR before (AAMR NH Blacks: 0.76 vs. NH white: 0.42 vs. Hispanics: 0.35) and during the pandemic (AAMR NH Blacks: 0.86 vs. NH white: 0.48 vs. Hispanics: 0.40). Older adults (age ≥65 years) had the highest AAMR before (AAMR >65 years: 0.79 vs. 45-64 years: 0.66 vs. 25-44 years: 0.45 vs. <25 years: 0.25) and during the pandemic (AAMR >65 years: 1.06 vs. 45-64 years: 0.60 vs. 25-44 years: 0.45 vs. <25 years: 0.22). Overall, AAMR was the same between metropolitan and non-metropolitan areas pre-pandemic (AAMR 0.47 for both). However, during the COVID period, AAMR was higher in non-metropolitan areas (AAMR Non-Metro: 0.58 vs AAMR Metro: 0.48). AAMR was highest in the West before the pandemic and in the Northeast post-pandemic, but differences across regions were not statistically signficant.
After two decades of decline, myocarditis-related mortality uptrended around 2020 with the COVID-19 pandemic. The APC post-COVID-19 was comparable across both genders, but greater in Hispanics and Blacks, in individuals >45 years and in those receiving care in non-metropolitan areas.