Among people who have strokes and COVID-19, there is a higher incidence of severe stroke as well as a higher incidence of stroke in younger people, according to new data from a multinational group published in the journal Stroke. The data also show that less severe strokes, mostly in critically ill patients or overwhelmed health centres, were underdiagnosed—something the research team said is “significant” because minor or less severe stroke may be an important risk factor for a more severe stroke in the future.
“Our observation of a higher median stroke severity in countries with lower healthcare spending may reflect a lower capacity for the diagnosis of mild stroke in patients during the pandemic, but this may also indicate that patients with mild stroke symptoms refused to present to the hospitals,” said Ramin Zand, the study group’s leader, and a vascular neurologist and clinician-scientist at Geisinger Health System (Danville, USA).
Throughout the pandemic, people with COVID-19 have reported symptoms involving the nervous system, ranging from a loss of smell or taste to more severe and life-threatening conditions, such as altered mental state, meningitis and stroke. A group of Geisinger scientists and a team of experts from around the world formed the COVID-19 Stroke Study Group shortly after the pandemic began to study the correlation between COVID-19 infection and stroke risk.
The COVID-19 Stroke Study Group’s latest report focuses on a cohort of 432 patients from 17 countries diagnosed with COVID-19 and stroke. Among this group, it found a significantly higher incidence of large vessel occlusion (LVO) strokes, with nearly 45% of strokes in the study group being LVOs compared to 24–38% of ischaemic strokes in the general population. The researchers also found a “much lower rate” of small vessel occlusion (SVO) and lacunar infarction among COVID-19 patients with stroke compared to prior population studies.
In addition, the study group saw a high percentage of young patients who had strokes. More than a third were younger than 55, and nearly half were younger than 65. This contrasts with pre-pandemic general population data, which showed 13% of strokes occurred in people under 55 and 21% occurred in people younger than 65, according to a Geisinger press release.
Results from the first phase of the study, which were published in EBioMedicine in September 2020 and included data on 26,175 patients, indicated an overall stroke risk of 0.5–1.2% among hospitalised patients with a COVID-19 infection. This finding demonstrated that, even though there were increasing reports of patients with COVID-19 experiencing stroke, the overall risk is low.
“Our initial data showed that the overall incidence of stroke was low among patients with COVID-19 and, while that has not changed, these new data show that there are certain groups of patients—for example, younger patients—who are more affected,” said Vida Abedi, a scientist in the department of molecular and functional genomics at Geisinger. “We hope these findings highlight new research directions to better identify patients at risk and help improve the quality of care.”