Stroke Risk Among Older Adults Highest in First 3 Days After COVID-19 Diagnosis

The risk of stroke among older adults diagnosed with COVID-19 was highest within the first 3 days of diagnosis, according to preliminary research to be presented at the American Stroke Association’s International Stroke Conference 2022.

“Stroke following the diagnosis of COVID-19 is a possible complication of COVID-19 that patients and clinicians should be aware of,” said lead study author Quanhe Yang, PhD, senior scientist in the Division for Heart Disease and Stroke Prevention at the US CDC in Atlanta, in a press release. “Vaccination and other preventive measures for COVID-19 are important to reduce the risk of infection and complications including stroke.”

Previous studies have examined the risk of stroke among adults with COVID-19; however, the findings were inconsistent, with a few focused specifically on older adults who are at greater risk of stroke.

For the current study, the authors evaluated the risk of ischemic stroke among older adults diagnosed with COVID-19 by examining the health records of 37,379 Medicare beneficiaries 65 years of age and older. The 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.

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 study objective was to compare 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.

Significant results found in the analysis include:

• The greatest risk of stroke occurred during the first 3 days after COVID-19 diagnosis, which is 10 times higher than during the control period.
• Following the first 3 days after COVID-19 diagnosis, the stroke risk quickly decreased but remained higher compared with the control period. Specifically, between days 4 and 7, the stroke risk was 60% higher than the control period. Between days 8 and 14, the stroke risk was 44% higher compared to the control period. The lowest stroke risk occurred after 15 to 28 days when the risk of stroke was 9% higher than during the control period.
• Among participants between 65 and 74 years of age, there was a greater risk of stroke after a COVID-19 diagnosis, compared to those 85 years of age and older, and among those without a history of stroke.
• There were no differences observed in stroke risk related to sex, race, and ethnicity.

“These findings can inform diagnosis, treatment and care of stroke among patients with COVID-19,” Yang said in the press release. “Further studies are needed to clarify the age-dependent risk of stroke associated with COVID-19.”

Study limitations include the possibility of misclassification from the use of Medicare real-time preliminary claims, in addition to the dates of COVID-19 diagnosis being possibly incorrect due to limited test availability. COVID-19 testing of hospitalized patients also became standard, which could have contributed to the finding of a greater risk of stroke in the days immediately following a COVID-19 diagnosis.

Finally, the study results may not apply to adults who are not beneficiaries in Medicare’s fee-for-service system.

REFERENCE

Stroke risk among older adults highest in first 3 days after COVID-19 diagnosis. American Heart Association. February 3, 2022. Accessed February 3, 2022. https://newsroom.heart.org/news/stroke-risk-among-older-adults-highest-in-first-3-days-after-covid-19-diagnosis?preview=b9b7