PREMPRO SIDE EFFECTS

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Prempro Side Effects:
Disease Rates for Women on Estrogen Plus Progestin (E+P) or Placebo
Disease	E+P	Disease
Heart Attacks	37	30
Strokes	29	21
Breast Cancer	38	30
Blood Clots	34	16
Colorectal Cancer	10	16
Hip Fractures	10	15
Endometrial Cancer	5	6
Deaths	52	53

The Section of the National Institute of Health (NIH) known as the National Heart, Lung, and Blood Institute (NHLBI) recently halted a major clinical study of Hormone Replacement Therapy involving Prempro. The study, conducted in conjunction with the Women's Health Initiative (WHI), sought to determine the long term effectiveness, safety, risks and benefits of combined estrogen and progestin therapy (known as HRT) in healthy menopausal women. The study, scheduled to continue until 2005, was stopped prematurely due to an increased risk of invasive breast cancer in study participants. Equally troubling was an increase in coronary heart disease, stroke, and pulmonary embolism in study participants on estrogen/ progestin combination therapy, as compared to women taking placebo pills. While some benefits were found in participants using estrogen plus progestin (a decrease in hip fractures and colon cancer), the increased risks of life-threatening conditions necessitated that the study be stopped immediately.

"We have long sought the answer to the question: Does postmenopausal hormone therapy prevent heart disease and, if it does, what are the risks? The bottom-line answer from WHI is that this combined form of hormone therapy is unlikely to benefit the heart. The cardiovascular and cancer risks of estrogen plus progestin outweigh any benefits--and a 26 percent increase in breast cancer risk is too high a price to pay, even if there were a heart benefit. Similarly, the risks outweigh the benefits of fewer hip fractures," said NHLBI Director Claude Lenfant, M.D.

In response to these findings, Wyeth Pharmaceuticals immediately began informing health care providers of the risks and benefits associated with the long-term use of HRT.

The study was stopped early because after 5.2 years the therapy's risks far exceed, outweighed and outnumbered the possible benefits from the drug.

Results from the estrogen plus progestin study show that the therapy not only did not protect against heart disease, but it also increased the risk of heart attacks, stroke, blood clots and increased the chance of breast cancer.

Study Results

Estrogen/progestin therapy resulted in a 26% increase in breast cancer, which caused the study to be stopped. No increase in deaths from breast cancer occurred from the combined therapy--or in deaths from other causes.

Estrogen/progestin therapy also resulted in:

41% increase in strokes
29% increase in heart attacks
Doubled rates of blood clots in legs and lungs
37% less colorectal cancer
34% fewer hip fractures and 24% less total fractures

More than 6 million women have taken the hormone replacement therapy over the last several years. People who have adverse effects from taking Prempro for hormone replacement therapy may have a claim against the manufacturer of the drug.

2002

WHI Hormone Program
The WHI Hormone Program is studying two types of hormone pills. One is estrogen plus progestin in women who had not had a hysterectomy before joining the WHI. The other is estrogen alone in women who already had a hysterectomy before joining. This "Update" describes new information about the estrogen plus progestin study.

Hormone Program Results Reviewed
The WHI Data and Safety Monitoring Board (DSMB) recently reviewed the health status of women in the Women's Health Initiative. Based on this review, the DSMB recommended that:

a.. Women in the study of estrogen plus progestin stop their study pills, because the risks now exceed the benefits.
b.. Women in the study of estrogen alone continue taking their study pills as before, because it remains uncertain whether the benefits outweigh the risks.

Assessing Risks and Benefits
In trying to understand the overall balance of risks and benefits of estrogen plus progestin, the DSMB reviewed information on many health conditions. Earlier "HRT Updates" told you about the effects of hormones on heart attacks, strokes, and blood clots. Now an important increase in breast cancer for women on estrogen plus progestin has become clear.

The graph below shows how often certain health events occurred in women taking estrogen plus progestin (darker bars) and in women taking placebo or inactive pills (lighter bars). Heart attacks, strokes, blood clots, and breast cancer occurred in more women on estrogen plus progestin. Fewer women on these hormones had colorectal cancer and hip fractures. There were no differences in the number of women who had endometrial cancer or in the number of deaths.

Graph data in table format.

How many women were affected?
Only 2.5% of women in the estrogen plus progestin study had these health events. These results tell us that during one year, for every 10,000 women taking estrogen plus progestin, we would expect:

a.. 7 more women with heart attacks. In other words, 37 women taking estrogen plus progestin would have heart attacks compared to 30 women taking placebo.
b.. 8 more women with strokes.
c.. 8 more women with breast cancer.
d.. 18 more women with blood clots.

These results also suggest that for every 10,000 women taking estrogen plus progestin, we would expect:

a.. 6 fewer colorectal cancers.
b.. 5 fewer hip fractures.
c.. Fewer fractures in other bones.

In summary, then, more women taking estrogen plus progestin had a serious health event than did women taking placebo. We conclude that estrogen plus progestin does not prevent heart disease and is not beneficial overall.

These results do not apply to women who had a hysterectomy before joining WHI and are participating in the study of estrogen alone. The DSMB recommended that the study of estrogen alone continue as planned. The balance of risks and benefits for women in the estrogen alone study is still uncertain. It is important to note that, to date, women in the estrogen alone study have not shown an increased risk of breast cancer.

Risks and Benefits of Estrogen Plus Progestin in Healthy Postmenopausal Women (JAMA. 2002;288:321-333)