National stroke study sets new practice standard for Canada

A Canada-wide clinical research study of more than 1000 stroke patients has put to rest a long-standing controversy about the use of thrombolysis for stroke. The two-year study, Canadian Alteplase for Stroke Effectiveness Study (CASES), recommends the widespread use of clot-busting drugs for acute stroke.

CASES, to be published in the May 10, 2005 edition of the Canadian Medical Association Journal, enrolled 1135 people in 60 centres between 1999 and 2001. Its goal was to assess the safety and effectiveness of clot-busting drugs known as tissue plasminogen activator (t-PA) as a routine treatment for acute stroke.

There were 33 community hospitals and 27 high-volume hospitals across Canada participating in the study. The research team found no differences in the rates of excellent outcome or intracranial hemorrhage between the high-volume hospitals and the community hospitals.

“These findings are extremely important because we now have definitive evidence that widespread use of t-PA for severe stroke will save lives, and help many people return to a completely normal life,” says Dr. Michael Hill, a co-author of the study, and a stroke neurologist in clinical neurosciences, University of Calgary Faculty of Medicine / Calgary Health Region.

Calgary’s “brain attack” team was the first in Canada to offer stroke patients the clot-busting drug t-PA. CASES finds that 37% of people treated with t-PA had an excellent clinical outcome. The drugs must be administered within three hours of the onset of stroke. “People need to get to hospital quickly,” says Hill.

“In this study, Canadian scientists confirm that t-PA is even more beneficial, and has fewer side effects than previous studies have shown,” says Dr. Antoine Hakim, CEO and scientific director, the Canadian Stroke Network. “Treatment with t-PA, when appropriate, improves excellent outcomes from stroke by 50 per cent."

“This study will help hospitals to develop stroke protocols for better treatments, not only in Canada, but around the world,” says Dr. Alastair Buchan, a co-author of the study, a professor of clinical geratology, and head, Acute Stroke Programme, University of Oxford.

CASES was supported by the Canadian Stroke Consortium, the Canadian Stroke Network, and Hoffmann-LaRoche Canada Ltd. Dr. Michael Hill’s research is funded by the Heart and Stroke Foundation of Alberta, NWT & Nunavut, the Canadian Institutes of Health Research, and the Alberta Heritage Foundation for Medical Research. Dr. Hill is a member of the Hotchkiss Brain Institute.