New study examines cardiovascular risks in Covid-19 survivors
The research was conducted in South Korea
Acute cardiovascular manifestations of COVID-19, such as heart failure, thrombosis, and dysrhythmia, are associated with increased mortality. To address the limitations of prior studies on this topic, researchers from Chung-Ang University, a private comprehensive research university located in Seoul, South Korea, examined whether Covid-19 survivors faced higher cardiovascular risks than non-COVID pneumonia patients. They analysed data from South Korean hospitals and found no overall increase in cardiovascular issues among Covid-19 survivors.
The emergence of the Covid-19 pandemic caused by severe acute respiratory syndrome-coronavirus marked a global health crisis with over 770 million cases of infection and six million deaths by September 6, 2023.
However, around 6.2% of the recovered individuals face lingering symptoms such as fatigue or respiratory problems. Although interstitial pneumonitis and severe acute respiratory distress syndrome are the main effects of Covid-19 on the lungs, the virus also affects other organs, especially the cardiovascular system.
Despite this, previous studies assessing cardiovascular outcomes in post-acute Covid-19 patients were limited by insufficiently adjusting for preexisting cardiovascular conditions among hospitalised individuals.
To overcome this limitation, a team of scientists led by Dr. Won-Young Kim and Professor Sun‑Young Jung from Chung-Ang University conducted a nationwide population-based cohort study.
They sought to explore the risk of cardiovascular outcomes among individuals who survived acute COVID-19 hospitalisation without preexisting cardiovascular conditions. The results of their study were published in the peer-reviewed online medical journal BMC Medicine on October 20, 2023.
The researchers used hospitalised patients with non-COVID-19 pneumonia as a historical comparison control group.
Dr Kim explained the rationale for this study design further: “Previous studies that assessed the risk of cardiovascular outcomes after Covid-19 selected general hospital admission as controls, neglecting the potential cardiovascular risks following non-Covid-19 pneumonia hospitalisation.
“In addition, the demographic composition of previous studies (based on mostly White and older male populations) may limit the generalizability of the results.”
The study utilised the South Korean National Health Insurance Service database, encompassing 97% of South Korea’s population.
The database offered comprehensive details on demographics, diagnoses, treatments, and outcomes linked to confirmed cases and vaccination information. The research focused on two groups—the first comprised 132,784 adults hospitalised for Covid-19between October 2020 and September 2021, while the second consisted of a historical control group of 31,173 adults hospitalised for non-COVID pneumonia between January and December 2019.
The primary outcome measured was major adverse cardiovascular events, with secondary outcomes encompassing specific cardiovascular conditions and mortality. Various other subgroup and sensitivity analyses were conducted along with statistical analyses.
Interestingly, the researchers found no increased incidence of post-acute cardiovascular issues in those adults hospitalised with COVID-19 compared to those hospitalised for non- Covid-19pneumonia.
Covid-19 survivors exhibited lower risks of all-cause mortality, congestive heart failure, and cardiac arrest but faced notably higher risks of acute myocarditis and deep vein thrombosis.
Further, younger Covid-19 patients, especially those without cardiovascular risk factors, showed elevated risks of cardiovascular complications, implying that COVID-19 may be an independent risk factor in this subgroup.
Sensitivity analyses with preexisting cardiovascular disease and subgroup assessments confirmed these trends, emphasising the impact of Covid-19 on cardiovascular outcomes. Additionally, non-vaccinated Covid-19 patients exhibited increased risks of various adverse cardiovascular events.
Discussing the results further, Dr Kim stated: “Our results suggest that Covid-19 vaccination may prevent cardiovascular outcomes. This supports vaccination, especially for patients with preexisting cardiovascular disease.”
This study is the first to compare the risk of cardiovascular outcomes between Covid-19and non- Covid-19pneumonia among the East Asian population.
While prior Western studies suggested elevated cardiovascular risks post-Covid-19, this research has revealed low risks in South Korean patients following acute Covid-19 hospitalisations. These findings can offer valuable insights for healthcare practitioners and policymakers to devise effective strategies for the long-term care of Covid-19 patients.
Featured image: The Covid-19 virus primarily attacks the cardiovascular system. Image: Fusion Medical Animation