Long-term cardiovascular events in individuals hospitalised with COVID-19: a retrospective cohort

BACKGROUND: Post-COVID condition encompasses a spectrum of persistent or emerging symptoms affecting multiple organ systems, including a heightened risk of cardiovascular complications. Despite growing recognition of this phenomenon, there remains a lack of comprehensive data regarding the incidence and risk factors associated with cardiovascular events during the post-acute phase in patients previously hospitalised for COVID-19. Thus, we aimed to estimate the incidence of cardiovascular events among patients hospitalised for COVID-19 in Portugal and assess the association between patient and infection characteristics and cardiovascular events in the COVID-19 post-acute phase. METHODS: We conducted a registry-based retrospective cohort study from seven hospitals across Portugal. Data was retrospectively collected from the electronic medical record of each patient. We included individuals hospitalised due to COVID-19 between March 2020 and March 2021. Our outcome of interest was cardiovascular events in the post-acute phase of COVID-19, occurring at least 30 days after a positive SARS-CoV-2 test. The variables of interest considered were the severity of the episode, existing cardiovascular risk and vaccination status before the SARS-CoV-2 test. Person-years was estimated for each individual, and incidence rates were estimated. A Cox proportional hazard regression model was employed to assess risk factors. RESULTS: We included 1,803 patients in the analysis, of which 143 (7.9%) experienced at least one cardiovascular event following COVID-19 hospitalisation. The overall incidence rate of having at least one cardiovascular event was 34.65 per 1,000 person-years (95% confidence interval (CI): 29.20; 40.82). We found higher risk of cardiovascular events for individuals with pre-existing cardiovascular risk (adjusted hazard ratio (aHR): 3.76, 95% CI: 1.53; 9.24) and lower risk for individuals with at least one vaccine dose before the SARS-CoV-2 test (partial vaccination - aHR: 0.44, 95%CI: 0.30; 0.64, complete vaccination - aHR: 0.46, 95%CI: 0.2; 0.80). We did not find a significant difference between the severity of the COVID-19 episode and the risk of having cardiovascular events post-COVID-19. CONCLUSION: Our findings suggest a substantial burden of cardiovascular complications post-COVID-19, underscoring the need for health services to be prepared and commence screening and preventive measures for individuals at higher risk.