07/04/2012 10:02 EDT | Updated 09/03/2012 05:12 EDT

Macular degeneration treatment doesn't increase cardiovascular risk: study

TORONTO - Toronto researchers have found that two drugs used to treat age-related macular degeneration do not increase the risk of cardiovascular events in people being treated for the eye condition.

The study found the drugs Avastin and Lucentis don't increase the risk of heart attacks or strokes in people who get small doses in the eye for macular degeneration, a leading cause of blindness.

The research was done by scientists at the Institute for Clinical Evaluative Sciences and is published in the medical journal BMJ.

The drugs have revolutionized the treatment of retinal diseases, improving the lives of millions.

However, they have been seen to increase the risk of vascular side-effects in people who take them intravenously for cancer.

The researchers wanted to ensure that wasn't also the case for people who have small doses of the drugs injected into their eyes.

The negative findings should be reassuring to people who use the drugs for macular degeneration.

"These finding are highly significant because while we've seen explosive growth in the use of both drugs worldwide, our understanding of the safety risks is incomplete," says Dr. Rob Campbell, a scientist at ICES and an ophthalmologist at the School of Medicine at Queen’s University in Kingston, Ont.

The study says that given what is known about how these drugs work, it was biologically plausible that adverse vascular events could have stemmed from their use.

"We've looked at this issue in two studies with different methods and found consistent results," Campbell says in a release.

But there remains a need for ongoing surveillance and further research into specific groups who may be at a particularly high risk, such as people with diabetes, he adds.

The drugs' generic names are bevacizumab (Avastin) and ranibizumab (Lucentis).