ABSTRACT
Background: The COVID-19 pandemic has endured for over three years with over twelve variants afflicting humans worldwide. The impact and longevity of the pandemic has driven the medical community and researchers to identify high-risk populations, yet few studies have explored temporal trends during the pandemic. The objective of this study is to investigate trends in all-cause mortality associated with co-morbid cardiovascular disease (CVD) throughout the consecutive waves of the COVID-19 pandemic. Methods: A retrospective cohort study was conducted on patients with COVID-19 infection who received care at a tertiary care center in Chicago between March 2020 and September 2022. Multivariable logistic regression was used to investigate associations between co-existing CVD (defined as congestive heart failure, myocardial infarction, cerebrovascular disease, peripheral vascular disease) and mortality, adjusting for age, sex, race, and comorbidities defined in the Charlson comorbidity index. Results: The study included 38651 participants (mean age 45 years, 57.6% female, 11.4% with co-existing CVD). All-cause mortality in COVID-19 patients was highest during the Delta wave and remained elevated until the late Omicron wave. Mortality associated with co-existing CVD increased during the early pandemic waves, decreased in the later waves, but remained elevated relative to the overall population. When adjusted for age, sex, and race, all-cause mortality was 2.3-fold higher in patients with co-existing CVD compared to those with non-CVD comorbidities (OR = 2.30, 95% CI 1.95 - 2.62; p < 0.001). Conclusions: While overall mortality rates declined toward the later waves of the pandemic, all-cause mortality associated with CVD remained elevated compared to individuals without CVD.