Beta blockers shown to combat osteoporosis

Researchers from Sydney’s Garvan Institute of Medical Researchhave shown that beta blockers can increase bone density and reduce the risk of osteoporotic fracture in around 50 per cent of patients.

Beta-blockers are a class of drug designed to counter the effects of stress hormones, and are commonly prescribed to treat heart problems, hypertension and certain anxiety disorders.

Using data collected data from the Dubbo Osteoporosis Epidemiology Study, professor Tuan Nguyen from Sydney’s Garvan Institute of Medical Research and PHd student Shuman Yang showed conclusively that people on beta-blockers have lower risk of fracture and better bone density. The Dubbo study is a 20-year project involving 2203 women and 1285 men, who were first seen between 1989 and 1993 and them had their bone density measured biennially.

A precursor to the Garvan study came a few years ago when researchers at Columbia University reported increased bone mass in mice given beta blockers.

“That was very significant, as it showed that the sympathetic nervous system has an effect on bone,” said professor Nguyen.

“So we set out to test the hypothesis that ‘if mice treated with beta blockers have increased bone mass, and we know that increased bone mass is associated with reduced fracture risk, then people on beta blockers should have reduced fracture risk’.”

“We found that indeed it was the case – beta-blockers reduced the risk of fracture by about 50 percent in men and women, which is dramatic. Drugs used specifically for treating osteoporosis also reduce fracture by around the same magnitude.”

The researchers also noted that the static level of osteoporosis fractures over the last four decades was most likely due to the coincidental increase in use of beta blockers by patients diagnosed with disorders such as hypertension and anxiety. Conversely, the researchers warned that the trend away from beta blockers as a treatment for these conditions could lead to a sharp increase in osteoporosis-related bone fractures in coming years.

“We estimate that in Australia, North America, Europe and Japan, where rising levels of obesity and high blood pressure have been treated with beta-blockers, fracture risk may have been reduced by as much as 29 percent,” professor Nguyen noted.

The Garvan study was published this week in the journal Bone.