Alarming study findings by researchers from the Heart Disease and Stroke Prevention Unit at the U.S. Centers for Disease Control and Prevention (CDC) in Atlanta shows that the risk of a COVID-related ischemic stroke appears greatest in the first three days after an individual has been diagnosed with the SARS-CoV-2 coronavirus. Not just higher, but 10 times greater than during the period before a person contracts COVID-19.
The preliminary research findings that have yet to be published will be present at the coming American Stroke Association’s International Stroke Conference 2022. https://professional.heart.org/en/meetings/international-stroke-conference/programming
Lead study author Dr Quanhe Yang, Ph.D., senior scientist in the Division for Heart Disease and Stroke Prevention at the U.S. CDC told “Stroke following the diagnosis of COVID-19 is a possible complication of COVID-19 that patients and clinicians should be aware of. Vaccination and other preventive measures for COVID-19 are important to reduce the risk of infection and complications including stroke.”
Numerous past studies have examined the risk of stroke among adults with COVID-19; however, research findings were inconsistent, and few focused specifically on older adults, who are at greater risk of stroke.
The COVID-19-Strokes study team from the U.S. CDC examined the risk of ischemic stroke, which is a stroke due to a blocked blood vessel, among older adults diagnosed with COVID-19 by examining the health records of 37,379 Medicare beneficiaries ages 65 and older.
Most of these patients were diagnosed with COVID-19 between April 1, 2020 through February 28, 2021 and were hospitalized for stroke from January 1, 2019 through February 28, 2021.
Typically stroke hospitalizations could occur before or after the diagnosis of COVID-19, however, those that occurred 7 days before diagnosis or 28 days after diagnosis served as a control period. The participants were, on average, 80 years old when diagnosed with COVID-19, and 57% were women.
More than 75% were non-Hispanic white adults; more than 10% were non-Hispanic Black adults; less than 10% were Hispanic adults, and the remainder were adults from other racial or ethnic groups.
The research team compared stroke risk in the days immediately before and after COVID-19 diagnosis to the risk during the other days of the study, or the control period.
Alarmingly the study findings showed that the greatest risk of stroke occurred during the first three days after COVID-19 diagnosis and was 10 times higher than during the control period.
It was also found that following the first three days after COVID-19 diagnosis, the stroke risk quickly declined yet remained higher compared to the control period. Specifically, between days 4-7 the stroke risk was 60% higher, and between days 8-14, the stroke risk was 44% higher compared to the control period. The lowest stroke risk occurredafter 15-28 days when the risk of stroke was 9% higher than during the control period.
Interestingly, a younger subset of participants, those ages 65-74 years old, had a greater risk of stroke after COVID-19 diagnosis, compared to those ages 85 and older, and among those without a history of stroke.
The study findings showed that there were no differences in stroke risk related to sex, or race and ethnicity.
Dr Yang added, “These study findings can inform diagnosis, treatment and care of stroke among patients with COVID-19. Further studies are needed to clarify the age-dependent risk of stroke associated with COVID-19.”
Strokes are currently the fifth leading cause of death in the United States.
A stroke is a medical emergency that occurs when a blood vessel to the brain becomes blocked or bursts, preventing oxygen and nutrients from reaching the brain.
Stroke is a major cause of long-term disability. Rapid treatment is critical to prevent brain damage or death, so it is important to recognize the warning signs of stroke and the correct action. The abbreviation F.A.S.T. stands for face drooping, arm weakness, speech difficulty, time to call 9-1-1 r any emergency health services.
Dr Louise McCullough, chair of neurology at UT Health Houston and chief of neurology at Memorial Hermann Hospital in Houston who was not involved with the study commented on the findings,”This new data provides a little bit of reassurance that early risk does decrease over time.”.
He added, “Typically the heightened risk associated with infection in general is likely due to inflammation, which may cause an increased risk of clotting or thrombosis. We’ve known this in infections for quite some time. The question is, is there a disproportionate risk due to COVID or is this just because these patients are very sick and in the hospital?”
Dr McCullough suggested, “The stroke risk may decline after those initial days because the patients’ infections are becoming under control, they’re receiving fluids and they’re getting steroids that decrease the inflammatory response.”
Dr Marc Bonaca, chair of the American College of Cardiology’s peripheral vascular disease council who was also not involved with the study commented, “Even early on, many of us heard about or experienced having young patients without risk factors at home with COVID and experiencing really terrible events like bad ischemic strokes.”
Dr Bonaca, who is also a professor of medicine and cardiology at the University of Colorado in Aurora further added, “The research findings remind patients and clinicians alike to treat risk factors like high cholesterol and high blood pressure, because if you are taking therapies that reduce stroke risk overall, that will reduce your risk if you do get COVID-19.
Having people’s blood pressure well-controlled, having people on statins and cholesterol-lowering medications and so on. I think this is a good reminder that we should be doing everything we can.”
He further stressed, “Healthy lifestyles are key as well. The 10-fold risk is based on your baseline risk, but if you can lower your baseline risk, your overall risk is lowered.”
Dr Yang said when the data becomes available, the study team intends to follow up with a similar study that includes information on vaccination status and COVID variants, such as Omicron and Delta.
The study’s limitations include the possibility of misclassification from the use of Medicare real-time preliminary claims, and the dates of COVID-19 diagnosis may be incorrect due to limited test availability, particularly early in the pandemic. Later, COVID-19 testing of hospitalized patients became standard, which may have contributed to the finding of a greater risk of stroke in the days immediately following a COVID-19 diagnosis.
Also, the study’s results may not apply to adults who are not beneficiaries in Medicare’s fee-for-service system.