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

BACKGROUND

Dedicated hypertrophic cardiomyopathy (HCM) center cohorts have reported reductions in HCM-related deaths, likely due to the introduction of contemporary treatments. Similar declining HCM mortality rates are reported in the general US population over 2 decades (1999-2019), but the impact of the COVID-19 pandemic on HCM has not been assessed.

METHODS AND RESULTS

Age-adjusted mortality rates based on death certificates from 1999 to 2022 were extracted from the Centers for Disease Control and Prevention Wide-Ranging Online Data for Epidemiological Research. HCM-related mortality trends were compared with non-HCM cardiovascular deaths and all-cause deaths. Excess HCM-related deaths were estimated during the 2020 to 2022 COVID-19 pandemic. From 1999 to 2019, HCM-related age-adjusted mortality rates declined progressively, reaching a cumulative 53% (95% CI, 50%-56%) reduction in 2019, exceeding declines in non-HCM cardiovascular disease (25%) and all-cause deaths (18%). Declines were evident among all age groups but were most substantial among patients aged 15 to 24 years (62%; 95% CI, 47%-73%) and 25 to 44 years (62% [95% CI, 56%-68%]) but less so in patients aged ≥65 years. During the COVID-19 pandemic, HCM-related deaths by 31% (95% CI, 23%-40%), exceeding increases in non-HCM cardiovascular and all-cause deaths. During the pandemic, 5462 HCM-related deaths were observed compared with 4770 expected deaths on the basis of the preceding period, resulting in a 692 estimated excess HCM-related deaths (95% CI, 554-830).

CONCLUSIONS

Based on an analysis of death certificates, the marked decline in HCM-related deaths of >50% achieved in the US general population during the 2 decades from 1999 to 2019 was substantially reversed (by 29%) during the subsequent 3-year COVID-19 pandemic.