Toronto, Jul 29 (IANS): Covid-19 infection raises the risk of stroke, often among younger and healthier patients, who are then likely to face worse outcomes, according to a study.

People with Covid are over 2.5 times more likely to have an unfavourable outcome and face a difficult recovery post-stroke.

Researchers from Thomas Jefferson University in the US found that the patients with Covid, who were younger and had less risk factors, were less likely to achieve successful revascularisation -- a procedure aimed to restore blood flow into blocked arteries or veins.

Moreover, thrombectomy -- a minimally invasive procedure that uses a catheter to reopen blocked arteries in the brain -- was prolonged in the Covid group, as was the length of hospital stay.

Most alarming, mortality rates were higher by more than two-fold in the Covid group compared to the control.

Overall, Covid was a predictor of poorer outcomes, even though many of the patients were younger, healthier and even had mild symptoms of the virus before the onset of stroke, the researchers said.

"There is still so much we need to learn about Covid, especially its impact on younger patients," said lead author Pascal Jabbour, Professor of neurological surgery at the university.

"Stroke's impact on individuals with Covid-19 is alarming and one we must continue to research and remedy," Jabbour added.

The findings were presented at the Society of NeuroInterventional Surgery's (SNIS) 19th annual meeting held in Canada.

For the study, researchers reviewed data for 575 patients with acute large vessel occlusion (LVO), 194 of which were Covid positive and the remaining 381 were not. The control group was composed of patients who presented with LVO and received a mechanical thrombectomy between January 2018 and December 2020.

The team compared which patients had successful revascularisations and left the hospital with little to no disabilities.

Of the individuals with Covid, the severity of the virus on stroke onset was moderate in 75.5 per cent of the cases, severe in 15.8 and critical in 8.7 per cent.

The mean duration between symptoms and stroke onset was about nine days, and 34 per cent of the Covid group had stroke as their first symptom of the disease.