Evidence of Declining Mortality Trends for Hypertrophic Cardiomyopathy in the United States and the Impact of the COVID‐19 Pandemic

Figures

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  Figure 1. Trends demonstrating the decreasing trajectory of HCM‐related deaths in the United States (1999–2019) (blue) and the reversals during the COVID‐19 pandemic (2020–2022) (orange). During the pre–COVID‐19 years, a 53% decline was observed. During the COVID‐19 pandemic, a 31% increase occurred abruptly. HCM indicates hypertrophic cardiomyopathy.

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  Figure 2. Mortality trends of HCM, non‐HCM cardiovascular disease, and all‐cause deaths in the United States, 1999 to 2022. A, Trends demonstrating declining HCM‐related deaths (blue) vs all‐cause deaths (grey) and non‐HCM cardiovascular‐related deaths (orange). For HCM, AAMR declined gradually, reaching a 53% cumulative decline from 9.1/million in 1999 to 4.2/million in 2019. Non‐HCM cardiovascular‐related AAMR declined 25% from 5190/million to 3874/million. All‐cause AAMR declined 18% from 8756/million to 7152/million. Percentage declines in HCM‐related deaths were greater than cardiovascular and all‐cause deaths (P<0.001 for both). During the COVID‐19 pandemic (2020–2022), AAMRs increased by 31% for HCM‐related deaths, 13% for non‐HCM cardiovascular‐related deaths, and 12% for all‐cause deaths. B, Relative changes comparing HCM‐related deaths (blue) vs all‐cause deaths (grey) and non‐HCM cardiovascular‐related deaths (orange) during the pre–COVID‐19 period and the COVID‐19 pandemic. The height of each bar represents the magnitude of change in mortality rates with respect to 1999. For example, a value of −10 in 2019 indicates the mortality rate was 10% lower in 2019 than in 1999. Dashed…

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  Figure 3. Age‐stratified declines in HCM‐related deaths in the United States, 1999 to 2019. Declines were greatest in individuals aged 15 to 44 y: <15 years (46% decline); 15 to 24 y (62% decline); 25 to 44 y (62% decline); 45 to 64 y (53% decline); and ≥65 y (48% decline). Smoothed lines of best fit are shown for each age group. HCM indicates hypertrophic cardiomyopathy.

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  Figure 4. Excess HCM‐related deaths during the COVID‐19 pandemic. A, Observed vs expected HCM‐related deaths before (orange) and after (blue) the COVID‐19 pandemic. Horizontal smooth red line represents expected HCM‐related deaths. The shaded area denotes the 95% CI. The dots represent the observed HCM‐related deaths before and after COVID 19. The model was trained on the dots left of the vertical dashed line, representing the pre–COVID‐19 data, and was then used to predict deaths occurring afterwards, assuming the absence of a COVID‐19 outbreak. The poor model fit (underestimation) of the dots to the right of the dashed vertical line represents excess deaths occurring with COVID‐19 that the model could not account for, with expected vs observed deaths being 4770 vs 5462 respectively. B, Cumulative excess HCM‐related deaths during the COVID‐19 pandemic. The solid red line represents the gradual accumulation of excess HCM‐related deaths. The black dashed horizontal line at 0 represents the hypothetical absence of cumulative excess deaths. The shaded area denotes the 95% CI. Cumulative excess deaths by December 31, 2022, were estimated at 692, a 14.5% increase above the expected number of…