Featured Research

from universities, journals, and other organizations

Bisphosphonates for osteoporosis not associated with reduced breast cancer risk, study suggests

Date:
August 11, 2014
Source:
The JAMA Network Journals
Summary:
An analysis of data from two randomized clinical trials finds that 3-4 years of treatment with bisphosphonates to improve bone density is not linked to reduced risk of invasive postmenopausal breast cancer. Some studies have suggested that bisphosphonates, which are commonly used to treat osteoporosis, may have antitumor and antimetastatic properties. Some observational studies have suggested bisphosphonates may protect women from breast cancer.

An analysis of data from two randomized clinical trials finds that three to four years of treatment with bisphosphonates to improve bone density is not linked to reduced risk of invasive postmenopausal breast cancer.

Some studies have suggested that bisphosphonates, which are commonly used to treat osteoporosis, may have antitumor and antimetastatic properties. Some observational studies have suggested bisphosphonates may protect women from breast cancer.

The authors analyzed the relationship of postmenopausal breast cancer and bisphosphonate use by examining data from two randomized, double-blind, placebo-controlled trials. The Fracture Intervention Trial (FIT) randomly assigned 6,459 women (ages 55 to 81 years) to alendronate or placebo with an average follow-up of 3.8 years. The Health Outcomes and Reduced Incidence with Zoledronic Acid Once Yearly-Pivotal Fracture Trial (HORIZON-PFT) randomly assigned 7,765 women (ages 65 to 89 years) to annual intravenous zoledronic acid or placebo with an average follow-up of 2.8 years. The authors compared rates of breast cancer in the bisphosphonate treatment groups to the placebo groups.

There was no significant difference in breast cancer rates between the bisphosphonate and placebo groups. In FIT, the breast cancer rate was 1.5 percent in the placebo group and 1.8 percent in the alendronate group. In HORIZON-PFT the rate was 0.8 percent in the placebo group and 0.9 percent in the zoledronic acid group. There also was no significant difference when data from the two trials were combined.

"These data provide evidence that three to four years of treatment with bisphosphonate, alendronate or zoledronic acid, therapy does not reduce the risk of incident breast cancer in postmenopausal women. The discrepancy between our results and the reports of associations in observational studies may be an example of indication bias and illustrates the limitation and hazard of drawing conclusions about treatment effects from observational studies (even those that are very well done) and emphasizes the value of confirming such associations in randomized trials. The effect of bisphosphonate treatment on breast cancer risk in nonosteoporotic populations should be investigated in other randomized trials."

In a related editor's note, Joseph S. Ross, M.D., M.H.S., a JAMA Internal Medicine associate editor, writes: "Whereas these findings highlight why it is so important for new therapies to be evaluated using RCTs (randomized clinical trials), they also reinforce the importance of assessing the methodological rigor of observational studies before interpreting real-world effects."

"Just as we closely scrutinize RCT design, so must we understand the quality and statistical power of the data used for observational studies, how participants were identified, the duration of follow-up, the end points examined, and the analytical strategy used. Observational studies are particularly valuable for clinical situations unlikely to be tested using RCTs, and many provide valid and reliable real-world evidence," Ross continues.

"Thus, whereas we all can remember examples of when RCTs and observational studies differed, less memorable are the even more numerous examples in which results were consistent. In the end, we should be open to all types of evidence and rely on rigorous clinical science to guide practice," Ross concludes.


Story Source:

The above story is based on materials provided by The JAMA Network Journals. Note: Materials may be edited for content and length.


Journal Reference:

  1. Trisha F. Hue, Steven R. Cummings, Jane A. Cauley, Douglas C. Bauer, Kristine E. Ensrud, Elizabeth Barrett-Connor, Dennis M. Black. Effect of Bisphosphonate Use on Risk of Postmenopausal Breast Cancer. JAMA Internal Medicine, 2014; DOI: 10.1001/jamainternmed.2014.3634

Cite This Page:

The JAMA Network Journals. "Bisphosphonates for osteoporosis not associated with reduced breast cancer risk, study suggests." ScienceDaily. ScienceDaily, 11 August 2014. <www.sciencedaily.com/releases/2014/08/140811170108.htm>.
The JAMA Network Journals. (2014, August 11). Bisphosphonates for osteoporosis not associated with reduced breast cancer risk, study suggests. ScienceDaily. Retrieved October 20, 2014 from www.sciencedaily.com/releases/2014/08/140811170108.htm
The JAMA Network Journals. "Bisphosphonates for osteoporosis not associated with reduced breast cancer risk, study suggests." ScienceDaily. www.sciencedaily.com/releases/2014/08/140811170108.htm (accessed October 20, 2014).

Share This



More Health & Medicine News

Monday, October 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Microneedle Patch Promises Painless Pricks

Microneedle Patch Promises Painless Pricks

Reuters - Innovations Video Online (Oct. 18, 2014) Researchers at The National University of Singapore have invented a new microneedle patch that could offer a faster and less painful delivery of drugs such as insulin and painkillers. Video provided by Reuters
Powered by NewsLook.com
Raw: Nurse Nina Pham Arrives in Maryland

Raw: Nurse Nina Pham Arrives in Maryland

AP (Oct. 17, 2014) The first nurse to be diagnosed with Ebola at a Dallas hospital walked down the stairs of an executive jet into an ambulance at an airport in Frederick, Maryland, on Thursday. Pham will be treated at the National Institutes of Health. (Oct. 16) Video provided by AP
Powered by NewsLook.com
Raw: Cruise Ship Returns to US Over Ebola Fears

Raw: Cruise Ship Returns to US Over Ebola Fears

AP (Oct. 17, 2014) A Caribbean cruise ship carrying a Dallas health care worker who is being monitored for signs of the Ebola virus is heading back to Texas, US, after being refused permission to dock in Cozumel, Mexico. (Oct. 17) Video provided by AP
Powered by NewsLook.com
Spanish Govt: Four Suspected Ebola Cases in Spain Test Negative

Spanish Govt: Four Suspected Ebola Cases in Spain Test Negative

AFP (Oct. 17, 2014) All four suspected Ebola cases admitted to hospitals in Spain on Thursday have tested negative for the deadly virus in a first round of tests, the government said Friday. Duration: 00:55 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins