How cautious should you be when taking a pharmaceutical purely for preventive measures? That depends on whom you ask.
I have a quick postscript to the e-Alert “Breathing a Word” (9/17/03) that examined a recent article in The National Review magazine online. The author of the article, Dr. Elizabeth Whelan, attempts to make a case for allowing drug company promotions to state “off label” health claims about certain drugs before thorough clinical testing is completed. In Dr. Whelan’s view, if a drug APPEARS to be a life-saver, then doctors should not delay in prescribing it to their patients.
Dr. Whelan singles out the drug Evista – a “designer estrogen” prescribed to address menopausal symptoms. Based on what she calls “mounting evidence” (not conclusive or overwhelming evidence) and one expert who states that Evista “clearly reduces the risk of breast cancer,” Dr. Whelan complains about a “blackout” on this “exciting, potentially life-saving” information. She compares Evista to a similar drug, tamoxifen, “which has already been approved to treat breast cancer and reduce risk in high-risk women.”
Tamoxifen? Bad call.
This week I happened across a study in the Journal of the National Cancer Institute titled “Estimates of the Number of U.S. Women Who Could Benefit From Tamoxifen for Breast Cancer Chemoprevention.” Applying a benefit/risk ratio, the researchers concluded that 5 percent of white women and less than 1 percent of black women would be potential candidates for chemoprevention with tamoxifen.
Why so few? The side effects tell the story. According to Breastcancer.org, most of the side effects of tamoxifen are not life threatening, but “they may still decrease your quality of life, sometimes to a considerable degree.” That’s because tamoxifen may bring on premature menopause along with symptoms such as hot flashes, nausea, vomiting, weight gain, mood swings, depression and loss of energy. And those are only the annoying side effects. The two dangerous side effects are an increased risk of blood clots and endometrial cancer.
Evista’s side effects also include mood swings, hot flashes, an increased risk of blood clots, and Evista has been shown to cause some postmenopausal women to begin menstruating again.
Are these acceptable sacrifices when trying to prevent a disease?
As I said, that depends on whom you ask.
To Your Good Health,
Health Sciences Institute
“The FDA Could be Hazardous to Your Health” Dr. Elizabeth Whelan, National Review Online, 8/21/03, nationalreview.com
“Estimates of the Number of U.S. Women Who Could Benefit From Tamoxifen for Breast Cancer Chemoprevention” Journal of the National Cancer Institute, Vol. 95, No. 7, 526-532, 4/2/03, jncicancerspectrum.oupjournals.org
“Drug Treatments to Prevent Breast Cancer” OB/GYN Clinical Alert, Thomson American Health Consultants, 4/1/03, ahcpub.com
“Side Effects of Tamoxifen” Breastcancer.org