People recovering from COVID-19 have an elevated risk of death for at least 18 months after infection, according to a study published in Cardiovascular Research.
By analyzing patients in UK Biobank, a large biomedical database, researchers sought to show if there are long-term associations between COVID-19, cardiovascular disease, and mortality. The study identified a prospective cohort of more than 7,000 people who developed COVID-19 between March and November 2020 and tracked them for 18 months.
Outcomes in the COVID-19 arm were compared to two control groups. First, each patient was matched to 10 people without COVID-19 during the 18-month study period to build a contemporary control arm of more than 70,000 people. A second historical control cohort of more than 70,000 people was then created. The historical control group featured data captured in 2018 to rule out the effects of reduced and canceled routine healthcare services during the pandemic.
The study showed that people with COVID-19 were 81 times more likely to die in the three weeks following infection than their counterparts in the control group. Risk of death remained elevated throughout the study. The likelihood of death was five times higher in the COVID-19 cohort at the end of the 18-month project. Study author professor Ian C.K. Wong of the University of Hong Kong, China, outlined what the findings mean for public health policy in a statement.
“COVID-19 patients were more likely to develop numerous cardiovascular conditions compared to uninfected participants, which may have contributed to their higher risks of death. The findings indicate that patients with COVID-19 should be monitored for at least a year after recovering from the acute illness to diagnose cardiovascular complications of the infection, which form part of long COVID,” Wong said.
Patients in the COVID-19 cohort were four times more likely to develop major cardiovascular disease in the 21 days after infection. COVID-19 patients remained 40% more likely to develop such disease over the rest of the 18-month study. Major cardiovascular disease and death were more common in people who had severe COVID-19 than their peers who had milder infections.
The data covers the period before vaccines against COVID-19 were available in the U.K. As such, while other researchers have generated evidence that vaccination may protect against complications, the new study is unable to determine if vaccines reduce the risk of cardiovascular disease and mortality in people who have breakthrough infections.