An underused therapy could offer hope to the thousands of patients who regularly monitor their blood to ensure they are taking the right amount of blood thinner medications.
Blood thinners, also called anticoagulants, save lives by preventing blood clots that can cause strokes or heart attacks. But they can be are tricky. If a patient takes too much, it can lead to uncontrolled bleeding; too little and the risk of blood clots returns.
So patients taking them have to go regularly to a medical lab for blood tests to make sure their blood is the right consistency. and to have their drug dosage adjusted.
Now, a Canadian study suggests a better option may be home testing.
Markham, Ont. resident Chris Daniels uses a home testing device. He is 32 and needs anticoagulants because he has a mechanical heart valve.
"It's a bit of a pain," he says. "It was a pain for me. I just thought 'Oh, if I have to do this every week for the rest of my life...' I just didn't want to do it."
Daniels found it difficult and expensive to get to a downtown lab for testing, since he doesn't drive. He also didn't like the fact that he had to wait for the results, which can take a day or two - in some cases, longer - and had to wait until then before he could adjust his dosage.
So he is among a handful of Canadians now using a portable home-testing unit, sold in Canada under such names as CoaguChek or ProTime.
Alan Payne, 71, also uses a unit. He takes warfarin and finds using the home blood testing machine much easier than trekking out to a lab.
"I feel I have some control over my own health. I don't mind the responsibility," he says. "It might not be for everybody, but I like to help myself."
Testing for anticoagulant levels is similar to diabetes monitoring. Users place a drop of their blood from their finger onto a test strip, and the strip is then inserted into the portable unit. Within seconds, the machine provides a reading, called an INR number, that indicates how quickly blood is clotting.
Dr. Phil Wells, the chief of the Division of Hematology at the Ottawa Hospital says research he's helped complete shows that patients who test themselves are more able to stay within the recommended therapeutic range of their medication.
Wells analyzed the results of 16 previous studies of home-based INR testing and found that the patients had fewer blood clots, fewer strokes and heart attacks -- and fewer deaths. the results are published in the Canadian medical journal, Open Medicine.
"It enables more accurate monitoring," he says. "This study shows for sure it's better for the patient. The only question that remains is what exactly it is that made it better for patients."
Heart valve patient Daniels thinks the devices are effective because the more frequent testing allows for faster changes in medication doses.
Home testing units are already widely used in some European countries, but in Canada, fewer patients are using them, in part because they can cost patients between $400 and $800 each. Patients are also in charge of paying for the disposable test strips.
Dr. Erik Yeo, the medical director of the thrombosis clinic at the University Health Network in Toronto, was not involved in Wells' study but says he's a big advocate of home coagulation monitoring.
"If the price gets a lot cheaper, you could come to a point where there may be a crossover where it would make sense to have many more patients on it," he says.
But he adds that he would not recommend that all his patients use the device. He says it's best for patients who can't get to a testing lab easily. He also notes that home testing cannot replace lab testing; patients still need to go in to a lab for monitoring, though less often.
"The INR test done in the lab is the gold standard and this is a test that is an approximation of that same test," says Yeo.
For now, Wells says further controlled trials are needed to determine whether it is patient education or frequency of testing that provides superior outcomes of home based testing.
With a report from CTV medical specialist Avis Favaro and producer Elizabeth St. Philip
