Stroke Risk Comparisons: COVID-19 vs. Influenza

Study Overview

Researchers at Weill Cornell Medicine in New York conducted a study to compare stroke rates in patients with COVID-19 and those with influenza. COVID-19, caused by the SARS-CoV-2 virus, primarily impacts the respiratory system, leading to symptoms such as fever, cough, and shortness of breath. However, as understanding of the virus expands, it has become evident that COVID-19 can also affect other bodily systems.

Hypercoagulable State and Stroke Risk

SARS-CoV-2 infection can induce a “hypercoagulable” state, increasing the likelihood of blood clot formation within the circulatory system. This condition raises the risk of stroke, which occurs when blood clots form in the brain, as well as other clotting complications.

Initial Findings on Stroke Risk

Early studies in China, France, and the United States indicated that COVID-19 might elevate stroke risk. However, these reports did not compare COVID-19 with other viral respiratory infections, like influenza, which is also recognized as a risk factor for stroke. The research team at Weill Cornell Medicine sought to fill this gap by analyzing stroke rates among COVID-19 and influenza patients.

Methodology

The study involved data collection from adult patients at two New York City hospitals. Patients with confirmed COVID-19 were analyzed from March 2 to May 2, 2020, while influenza patients were studied from January 1, 2016, to May 31, 2018. Neurologists calculated and compared the stroke rates between the two groups.

Results of the Study

Out of 1,916 patients with COVID-19, 31 (1.6%) experienced acute strokes. In contrast, only 3 out of 1,486 influenza patients (0.2%) had strokes. The findings revealed that the risk of stroke in COVID-19 patients was nearly eight times higher than that of influenza patients, with an odds ratio of 7.6. This calculation took into account various factors, including age, sex, race, vascular risk factors, viral symptoms, and intensive care unit admissions.

Conclusions and Recommendations

The researchers concluded that patients with COVID-19 are at a significantly higher risk of stroke compared to those with influenza. While these initial findings warrant further investigation, the study emphasizes the importance of healthcare providers being vigilant for stroke symptoms in COVID-19 patients. Early intervention, including the use of anti-clotting treatments, may be crucial in managing this increased risk.

Reference

Merkler AE, Parikh NS, Mir S, et al. Risk of ischaemic stroke in patients with coronavirus disease 2019 (COVID-19) vs patients with influenza. JAMA Neurol. Published online July 2, 2020. DOI:10.1001/jamaneurol.2020.2730

Image Credit

Image by PIRO4D from Pixabay