07/12/2012 06:15 EDT | Updated 09/11/2012 05:12 EDT

Too few stroke victims call 911 for urgent help

Quick diagnosis and treatment are critical in treating a stroke, but many people are still waiting too long to seek medical attention, including calling an ambulance to get to hospital, according to a new Ontario study.

More than one in three Ontario stroke patients did not arrive at the hospital by ambulance, says the study from the Canadian Institutes for Health Information released Thursday.

It looked at treatment of more than 62,000 stroke patients in Ontario from 2006-07 through 2009-10.

"Research has shown that early identification of stroke symptoms and treatment of stroke are crucial to improving a patient’s chance for recovery," said Jeremy Veillard, of CIHI.

For some patients, whose stroke is caused by a blocked artery for example, there is a short window to limit or reduce brain damage. They must arrive at hospital within 3½ hours of experiencing symptoms to be eligible for clot-busting drugs.

Medical staff often use the term “time is brain" to refer to the fact that clot-busters received within these first critical hours after a stroke can significantly reduce the damage to the brain.

According to Canadian best practice recommendations, "people who suddenly experience the warning signs of stroke should treat those signs as a medical emergency and immediately call 911. They should not wait to see a family doctor, they should not 'sleep it off' and they should not drive themselves to the hospital."

Ambulance paramedics are trained to assess patients for the telltale signs of stroke and will ensure a patient gets to the right hospital for care. Small hospitals without CT scanners cannot diagnose strokes and give the clot-busting drugs that are crucial for minimizing the damage of a stroke. Paramedics can also call ahead so hospitals can have stroke teams on hand when the patient arrives.

There are several possible reasons why patients with stroke do not call an ambulance, the study found.

Many patients and people around them may not recognize the symptoms of stroke or understand the importance of timely treatment.

"So the message we have to get out is a) recognize the symptoms and b) don't take that chance. Because it could be the difference between walking out of the hospital of your own accord in a week or two versus ending up in permanent long-term care," said Patrice Lindsay of the Canadian Stroke Network, who is a stroke survivor.

In a 2003 survey the Heart and Stroke Foundation of Canada found that 22 per cent of Ontarians could not identify any symptoms of stroke.

After the foundation launched a national awareness campaign, that figure dropped to 15 per cent, and the percentage of Canadians who could name at least two symptoms rose to 68 per cent from 52 per cent.

Still, even among those recognize symptoms, some think their condition is not that severe.

Moreover, some patients have to pay out of pocket for ambulance transport, underlying their reluctance to call 911.