The risk of heart attack and stroke is increased three-fold in the first two weeks following COVID-19, according to a study published in The Lancet journal.
The study compared the occurrence of acute myocardial infarction or heart attack, and stroke in 86,742 COVID-19 patients with 348,481 control individuals in Sweden from February 1 to September 14, 2020.
“We found a three-fold increased risk of acute myocardial infarction and stroke in the first two weeks following COVID-19,” said Osvaldo Fonseca Rodriguez from Umea University in Sweden, and co-first author of the study.
A study of #COVID19 cases using Swedish registry data suggests COVID-19 is a risk factor for acute myocardial infarction and ischaemic stroke.
The findings further highlight the need for vaccination, say authors. Read in full: https://t.co/h9M7LTtZGT pic.twitter.com/vg4Mz8xJRa
— The Lancet (@TheLancet) August 2, 2021
The risk was same even after the researchers adjusted for known risk factors for acute myocardial infarction and stroke such as comorbidities, age, gender and socio-economic factors.
“The results indicate that acute cardiovascular complications represent an important clinical manifestation of COVID-19,” said Ioannis Katsoularis from Umea University, a co-author of the study. “Our results also show how important it is to vaccinate against COVID-19, in particular the elderly who are at increased risk of acute cardiovascular events,” Katsoularis said.
The researchers used two statistical methods in the study: the matched cohort study and the self-controlled case series. The self-controlled case series study is a method that was originally invented to determine the risk of complications following vaccines, they said.
“Both the methods suggest that COVID-19 is a risk factor for acute myocardial infarction and ischaemic stroke,” the authors of the study said. “This indicates that acute myocardial infarction and ischaemic stroke represent a part of the clinical picture of COVID-19, and highlights the need for vaccination against COVID-19,” they said.
In the study, information from national registries from the Public Health Agency of Sweden, Statistics Sweden and the National Board of Health and Welfare were cross-linked for all reported COVID-19 patients. A control group consisting of four individuals matched to every COVID-19 case on age, gender and county of residence, that had not tested positive for COVID-19. By using historical registry data from the National Board of Health and Welfare’s inpatient registry, individuals with a previous myocardial infarction and stroke were identified and excluded from the study.
“It would have been difficult to calculate the risk that COVID-19 contributes to acute myocardial infarction and stroke, if individuals with a prior event were included,” said Krister Lindmark, a co-author of the study. “This is because the risk of a recurrent acute myocardial infarction and stroke is increased following a first acute myocardial infarction or stroke,” Lindmark added.