Featured Research

from universities, journals, and other organizations

Analysis Of Tamoxifen Studies Reveals Slight Increase Of Stroke Risk

Date:
October 12, 2004
Source:
American Academy Of Neurology
Summary:
A recent analysis of tamoxifen studies completed since 1980 revealed an increased risk of stroke in women who were randomized to tamoxifen versus placebo or other therapies. Details of the analysis and the researchers’ conclusions are reported in the October 12 issue of Neurology, the scientific journal of the American Academy of Neurology.

St. Paul, Minn. – A recent analysis of tamoxifen studies completed since 1980 revealed an increased risk of stroke in women who were randomized to tamoxifen versus placebo or other therapies. Details of the analysis and the researchers’ conclusions are reported in the October 12 issue of Neurology, the scientific journal of the American Academy of Neurology.

Related Articles


More than 250,000 U.S. women are diagnosed with breast cancer each year. Breast cancer accounts for nearly one in three cancers diagnosed in the U.S. and is the second leading cause of death for women. Fortunately, 90 percent of breast cancers are now diagnosed at localized and regional stages, for which five-year survival rates are 97 percent and 79 percent, respectively. Tamoxifen, a medication in pill form that interferes with the activity of estrogen, has been used for more than 20 years to treat patients with advanced breast cancer. It is used as adjuvant, or additional, therapy following primary treatment for early stage breast cancer. In women at high risk of developing breast cancer, tamoxifen reduces the chance of developing the disease.

In addition to its effects on breast cancer, the benefits of tamoxifen include increased bone mineral density, reduced risk of hip fractures, and lower levels of cholesterol. While tamoxifen is known to increase the risk of blood clotting in women with cancer, its relationship to stroke risk has been unclear. Because tamoxifen increases the risk of thromboembolism (a blood clot that has traveled from its site of origin to another vessel), its use could be associated with a higher risk of ischemic stroke (arterial obstruction) as compared to hemorrhagic (bleeding) stroke.

Researchers from Duke University Medical Center sought to determine the overall risk of both ischemic stroke and all strokes associated with tamoxifen. They conducted a systematic review of all clinical trials of tamoxifen published since 1980 using MEDLINE.

Nine trials met their inclusion criteria, with 39,601 total subjects enrolled, 19,954 of whom were randomized to tamoxifen. Six of the trials specifically reported ischemic stroke events. All trials used a standard dose of tamoxifen (20 mg daily).

“With tamoxifen, we found the frequency of all strokes was 1.06 percent and for ischemic stroke was 0.71 percent, versus 0.39 percent with controls,” reported study author Cheryl Bushnell, MD, MHS. The risk of ischemic stroke increased by 82 percent and risk of all strokes by 29 percent in women randomized to tamoxifen versus placebo or other therapies. Bushnell concluded, “The absolute increase in risk was small.”

“The results of this analysis support the practice of careful screening of women who are being considered for tamoxifen therapy,” noted Bushnell, “although physicians and their patients should be reassured that the absolute risk of stroke may be very low. In many women, this risk of stroke with tamoxifen may be outweighed by the benefit of treating or preventing breast cancer. In addition, women should not stop their prescribed therapy based on this study.”

Results of this analysis should be interpreted with some caution. Among other variables, specific stroke risk factors of the women in these studies were not reported, and the methods of determining ischemic or other types of stroke were not documented in any of the trials. Ongoing studies of tamoxifen that are designed to carefully track stroke events will further clarify this risk.

The study was supported by a grant from the National Institutes of Health and a National Stroke Association Research Fellowship.

The American Academy of Neurology, an association of more than 18,000 neurologists and neuroscience professionals, is dedicated to improving patient care through education and research. A neurologist is a doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system such as stroke, Alzheimer's disease, epilepsy, Parkinson's disease, autism and multiple sclerosis.

For more information about the American Academy of Neurology, visit its web site at http://www.aan.com.


Story Source:

The above story is based on materials provided by American Academy Of Neurology. Note: Materials may be edited for content and length.


Cite This Page:

American Academy Of Neurology. "Analysis Of Tamoxifen Studies Reveals Slight Increase Of Stroke Risk." ScienceDaily. ScienceDaily, 12 October 2004. <www.sciencedaily.com/releases/2004/10/041012090021.htm>.
American Academy Of Neurology. (2004, October 12). Analysis Of Tamoxifen Studies Reveals Slight Increase Of Stroke Risk. ScienceDaily. Retrieved October 24, 2014 from www.sciencedaily.com/releases/2004/10/041012090021.htm
American Academy Of Neurology. "Analysis Of Tamoxifen Studies Reveals Slight Increase Of Stroke Risk." ScienceDaily. www.sciencedaily.com/releases/2004/10/041012090021.htm (accessed October 24, 2014).

Share This



More Health & Medicine News

Friday, October 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Breakfast Debate: To Eat Or Not To Eat?

Breakfast Debate: To Eat Or Not To Eat?

Newsy (Oct. 23, 2014) Conflicting studies published in the same week re-ignited the debate over whether we should be eating breakfast. Video provided by Newsy
Powered by NewsLook.com
Ebola Fears Keep Guinea Hospitals Empty

Ebola Fears Keep Guinea Hospitals Empty

AP (Oct. 23, 2014) Fears of Ebola are keeping doctors and patients alike away from hospitals in the West African nation of Guinea. (Oct. 23) Video provided by AP
Powered by NewsLook.com
Despite Rising Death Toll, Many Survive Ebola

Despite Rising Death Toll, Many Survive Ebola

AP (Oct. 23, 2014) The family of a Dallas nurse infected with Ebola in the US says doctors can no longer detect the virus in her. Despite the mounting death toll in West Africa, there are survivors there too. (Oct. 23) Video provided by AP
Powered by NewsLook.com
Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Working Mother (Oct. 22, 2014) Is your child ready? Video provided by Working Mother
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