A drug used to ease chest pain in millions of people with heart disease may prevent bone loss by osteoporosis patients, new Canadian research suggests.
Researchers at Toronto's Women's College Hospital have found that nitroglycerin, which is prescribed in pill, patch or spray form to relax blood vessels in the heart, may also have another use: building bones.
For their study of more than 240 older women, researchers gave half of their subjects nitroglycerin cream and the other half a placebo.
"What we found is that the bone density improved by about seven per cent at the spine and at the hip over two years, which is pretty phenomenal and equivalent to a lot of the medications that are on the market for osteoporosis," said Dr. Sophie Jamal.
The researchers also found that subjects experienced an increase in their bone thickness and size, and suffered few side-effects.
As many as two million Canadians have osteoporosis, including about one in four women over the age of 50 and one in eight men. Common treatments can lead to a variety of unpleasant side-effects. For instance, bisphosphonates, which help build bone density and prevent against fractures, can lead to nausea and stomach discomfort. Drugs that mimic the hormone estrogen can cause hot flashes and increase the risk of blood clots.
Participant Edith George said another reason to be buoyed by the study's finding is the cost: treatment with nitroglycerin costs about 5 cents per day.
"As I was told (that) I realized this is something that can be used for people with this horrific disease in third world countries," George told CTV News.
While the study's findings are encouraging to the researchers and patients alike, experts caution that it has yet to be proven whether nitroglycerin can prevent bone fractures in those with osteoporosis.
"I would be very cautious with self-medicating with an agent, albeit a very safe one because it has been around a long time, until we have the information from the necessary additional studies that it actually decreases fracture risk," said Dr. Robert Josse of the Osteoporosis Centre at Toronto's St. Michael's Hospital.
The Canadian doctors say they are planning further, larger studies with researchers in the United Kingdom and the United States.
With a report from CTV's medical specialist Avis Favaro and producer Elizabeth St. Philip