COVID-19 may up ischaemic stroke severity

Patients with COVID-19 who experience an ischaemic stroke may have worse outcomes, including greater stroke severity and mortality risk, than those without COVID-19, findings from the Global COVID-19 Stroke Registry showed.

In this multinational (28 sites in 16 countries), observational study, 174 consecutive patients hospitalized with laboratory-confirmed COVID-19 who experienced an acute ischaemic stroke (median age 71.2 years, 37.9 percent female) were propensity score matched 1:1 with patients with acute ischaemic stroke without COVID-19 who were registered in the Acute Stroke Registry and Analysis of Lausanne Registry between 2003 and 2019 (330 patients included in analysis). Median National Institute of Health Stroke Scale (NIHSS) was 10.

Twenty patients (11.5 percent) had a history of stroke. The most common stroke risk factors and comorbidities were hypertension (68.4 percent), obesity (37.4 percent), and diabetes (31.03 percent). There was a median 7 days between the first COVID-19 symptoms and stroke onset.

Stroke severity, as determined by NIHSS score, was greater among patients with vs without COVID-19 (median 10 vs 6; p=0.03; odds ratio [OR], 1.69, 95 percent confidence interval [CI], 1.08–2.65). [Stroke 2020;doi:10.1161/STROKEAHA.120.031208]

Prevalence of large artery and lacuna stroke did not differ according to presence or absence of COVID-19 (p=0.082). Of the 48 deaths that occurred, 22 and 26 were due to COVID-19 and stroke, respectively. Ninety-six survivors had information available on disability status, of whom 49 were deemed severely disabled.  

Patients with COVID-19 had a higher risk of severe disability post-stroke compared with patients without COVID-19 (median modified Rankin Scale 4 vs 2; p<0.001) and were also at an increased risk of mortality (OR, 4.3, 95 percent CI, 2.22–8.30).

“Our findings suggest that COVID-19-associated ischaemic strokes are more severe with worse functional outcome and higher mortality than non-COVID-19 ischaemic strokes,” said the researchers.

Several reasons may explain the increased stroke severity among patients with COVID-19, they continued. “It was proposed that viral infections may cause a direct vasculopathic effect (endotheliopathy) or potentiate the prothrombotic milieu via several mechanisms including immune-mediated platelet activation, dehydration, and infection-induced cardiac arrhythmias.”

It remains to be seen if the increased severity of stroke in patients with COVID-19 applies to all types of ischaemic stroke or is primarily due to the increase in large-vessel occlusion strokes.

The increased severity of strokes among patients with vs without COVID-19 may explain the disability outcome, they added. “The broad multisystem complications of COVID-19 including acute respiratory distress syndrome, cardiac arrhythmias, acute cardiac injury, shock, pulmonary embolism, cytokine release syndrome, and secondary infection, probably contribute further to the worse outcomes including higher mortality in these patients.”

The results call for further research into establishing the mechanism behind the association, said the researchers.

“Given that severe strokes are typically associated with poor prognosis and can be very efficiently treated with recanalization techniques, confirmation of this putative association is urgently warranted in a large representative patient cohort to alert stroke clinicians and inform pre- and in-hospital acute stroke patient pathways,” they said.