Previous animal and human studies have shown this benefit, including one observational study that showed that women over age 50 who took beta-blockers had a 30% decrease in fractures, writes researcher Raymond G. Schlienger, PhD, MPH, a pharmacologist with the University of Basel in Switzerland.
His study appears in this week's Journal of the American Medical Association (JAMA).
"Many elderly patients with [high blood pressure] are at risk of developing osteoporosis, and they may potentially profit from positive effects of the relatively inexpensive beta-blockers and thiazide diuretics," writes Schlienger.
The drugs are thought to protect bones from being leaching of calcium, he explains. However, no studies have looked at effects of these medications on bones of men or young women.
In his study, Schlienger identified 30,600 people with fractures and compared them with 120,820 who had no fractures. The men and women in this study were between 30 and 79 years old. The study did not include an analysis of the effects of these medications in people with medical conditions that might affect bone metabolism such as cancer or alcoholism. People with osteoporosis were also excluded from the study.
- For current users of beta-blockers: Short-term use of the beta-blocker propranolol -- less than six months -- did not affect their fracture risk. But nine months after starting the drug, the risk reduction became apparent. There was a 15%-33% reduction in fracture risk with long-term use of beta-blockers.
- When the researchers looked at long-term use -- greater than 20 prescriptions -- of the medication, men were found to have benefited more than women. Overall the risk of fracture was reduced by 30% in men compared with women whose risk reduction, after 20 prescriptions for beta-blockers, was only 8%. However, it's likely that the women's overall health -- plus all the other medications they were taking -- plays a role in this, he speculates.
Beta-blockers seem to stimulate processes that strengthen bones, he explains. The same effect has been seen in mouse and rat studies.
Human studies have shown a similar benefit in thiazide diuretics. These drugs are commonly known as 'water pills.'
In the study, the use of thiazide diuretics was associated with a 20% reduction in fractures.
As for other heart drugs:
- Statin cholesterol-lowering drugs have also shown a slight decrease in fracture risk, he notes. The benefits were seen in those who were current long-term users of the drug. In other words, in people currently taking statins, and who have had greater than 20 prescriptions filled, had a reduced fracture risk of 15%. However, other cholesterol drugs haven't shown that benefit.
- Calcium channel blockers, yet another heart drug, have also not provided bone benefits.
- Long-term use of ACE inhibitors has been shown to cut fracture risk.
A few caveats: Schlienger's study did not take into account lifestyle factors such as physical activity and diet, which would also reduce fractures. The study also showed that the reduction in fracture risks varied by site and by age.