Nitroglycerin Boosts Bone Density And Bone Strength

Nitroglycerin is best known as a high explosive or a treatment for angina, but a new study in the February 23rd issue of the Journal of the American Medical Association says it may also be an effective therapy to strengthen bones and treat osteoporosis.


"Our findings demonstrate that nitroglycerin ointment, in very low doses, can increase bone density and improve bone geometry," says Sophie A Jamal, MD, PhD of the Women's College Research Institute and University of Toronto, Canada, and the lead author of the study. "Nitrates are widely available and inexpensive. As such these agents might be a promising way to reduce osteoporosis world wide."


"This is an exciting new treatment that is unlike any other drugs now used for osteoporosis," says Steven R. Cummings, MD, of the San Francisco Coordinating Center at the California Pacific Medical Center Research Institute, and the senior author of the study. "While other treatments work by either slowing the breakdown of bone, or increasing bone formation, nitroglycerin does both at the same time. It's a unique quality that leads to an apparent increase in bone strength."


Jamal, Cummings, and researchers at the University of Toronto, Canada, followed 243 postmenopausal women for 24 months in a single center, double-blind, placebo controlled study. The women, none of whom had osteoporosis, were randomly assigned to receive either nitroglycerin ointment or a placebo. They pasted the ointment onto their skin at bedtime.


At the end of the two year study women who were assigned to the nitroglycerin ointment group saw an increase of 7 percent in the bone mineral density (BMD) in their hip bones compared to women who were given a placebo. BMD indicates bone quantity- a strong indicator of fracture risk.


"One of the most striking effects was the increase in cortical width or the thickness of the bone," say Jamal and Cummings. "The nitroglycerin group saw an increase of almost 25 percent in their legs and an increase of 15 percent in their arms, compared to the placebo group. This was unexpected because it's not something you see with existing therapies."


There were some side effects of the treatment: about 25% of women had headaches with nitroglycerin and did not participate in the study. Of women who were enrolled, about 5% stopped because of headache.


The researchers say the results from the study are very encouraging but further larger trials are needed, both to replicate these findings and to determine the effects on fracture, before any treatment recommendations can be made. Because nitroglycerin is not a patented product further research would most likely involve the support of, and funding from, the National Institutes of Health.


Source: California Pacific Medical Center