Should I Take Hormone Replacement Therapy
History is full of great teams. There's Burns and Allen, Lewis and Clark, Barnum and Bailey—and estrogen and progesterone, two hormones that, until menopause, coordinate the activities of a woman's reproductive system.
During your reproductive years, these two hormones formed a tag team to trigger your monthly menstrual cycle. During the first part of the month, estrogen levels rose. Your uterus walls thickened to provide nourishment for an anticipated embryo. At ovulation your estrogen levels dropped then rose two days later, and production of progesterone (the synthetic version is called progestin) shifted into high gear to maintain a pregnancy. If you weren't pregnant, toward the end of the cycle, levels of estrogen and progesterone both went down. Your uterus shed the extra lining—and you got your period.
Hormone replacement therapy (HRT) mimics this process. Earlier forms of the therapy were thought to present risks: Going on the therapy would increase your risk of uterine and, perhaps, breast cancer. But there was a trade-off, because the extra hormones also cut your risk of heart disease, strengthened your bones, and possibly gave you more energy—which is why doctors typically recommended it. A hard choice? You bet it was.
Today, the bite has been taken out of the cancer risk that used to go along with estrogen replacement therapy.
Part of that is because doctors used to think that only estrogen by itself helped protect women against heart disease and other risks. But researchers have found that when estrogen and progestin team up, they do just about as well. Together, they form one of the all-time great teams for protection: Estrogen protects your heart and bones, while progestin keeps your uterus safe from cancer.
In terms of cost alone, this dollar-a-day lifelong preventive therapy is clearly preferable to treating such diseases. And the cost of hormone replacement therapy is often picked up by insurance, particularly if you have medical reasons such as risk factors for heart disease.
But even in the old days when women had to weigh one risk against the other, one clear-cut winner emerged.
Keep Your Heart Healthy with Hormones
Doctors agree—hormone replacement therapy protects your heart, providing up to a 50 percent reduction in heart disease risk.
In one study doctors focused on women who began using estrogen as early as 1969 and followed them for more than 17 years. "The women on HRT had a lower mortality rate," says Gary D. Friedman, M.D., a researcher at Kaiser-Permanente Medical Care Program in Oakland, California, who worked on the study.
Dr. Friedman adds that these women did show a higher rate of uterine cancer. "We expected to see that because most women had started taking estrogen so long ago, before the combination of estrogen and progestin virtually eliminated the added risk. But most of those cancers were cured. It is a lot easier to cure uterine cancer, if caught early, than coronary heart disease. The death rate from heart disease is much higher, and heart disease is much more common."
"Every woman should consider hormone replacement therapy. The benefits far outweigh the risk," says Trudy Bush, Ph.D., professor of epidemiology and preventive medicine at the University of Maryland School of Medicine in Baltimore. She is the principal investigator for the Heart and Estrogen/Progestin Replacement Study at the Johns Hopkins Women's Research Core in Lutherville, Maryland.
Here is what hormone replacement therapy does to cut your risk of heart disease and stroke.
HRT controls cholesterol. "Estrogen tends to reduce the levels of the 'bad' low-density lipoprotein (LDL) cholesterol and raise the 'good' high-density lipoprotein (HDL) levels. That is one way that estrogen may help to prevent coronary heart disease," says Dr. Friedman. Scientists note that low HDL and high LDL are key culprits in increased heart disease risk. You get nearly as much benefit if you were on estrogen-plus-progestin therapy as you would from estrogen alone.
It is blood pressure-friendly. Good news: Hormone replacement therapy has very little effect on blood pressure. In fact, it may actually lower it. Researchers note that it actually seems to relax the blood vessels, opening them up so that the blood is under less pressure.
HRT reduces clot risk. One study suggests that hormone replacement therapy reduces the blood's tendency to clot, which might lower heart attack and stroke risk. Researchers think that is because the therapy causes a change in blood flow and other factors that affect clot formation.
It protects your arteries. In a tantalizing study, researchers found that hormone replacement therapy may actually keep the important carotid arteries from thickening and narrowing, reducing your risk of a stroke. Researchers used ultrasound to examine the thickness of artery walls. "As atherosclerosis develops, you see a lot of bumps and thickenings along the artery walls. In women who were using the therapy, that didn't happen. But it progressed in women who were not using it," says Mark Espeland, Ph.D., professor of biostatistics at the Bowman Gray School of Medicine of Wake Forest University in Winston-Salem, North Carolina, who conducted the study.
In general, women who take hormone replacement therapy have more flexible arteries than those who don't.
"It's not clear whether that translates into a reduced risk of stroke," says Dr. Espeland.
| Keep Cellular Division on Target It sounds like a bad riddle: Why does estrogen increase risk of one cancer and decrease the risk of others? Estrogen is like the lawman of old TV westerns—it keeps the citizens, or cells, in line. Researchers note that cells are most vulnerable to cancer when they are dividing. Estrogen helps control cell division and prevent uncontrolled growth, the body's equivalent of riots in the streets. The exception? Estrogen's other job is to build up the lining of the uterus. As part of that process, it encourages cell division. As cells divide and replicate rapidly, there is more opportunity for a mutation that can lead to cancer. That is why progestin is commonly included in the therapy. It causes the body to shed the lining of the uterus, protecting you from cancer. |
Beat the Cancer Risk
Nothing is perfect, and hormone replacement therapy has long been linked with the risk of cancer. Here is a breakdown on how cancer links up with HRT and what you can do to avoid the risks.
Endometrial cancer. "This is really a nonrisk," says Alvin F. Goldfarb, M.D., professor in the Department of Obstetrics and Gynecology at the Jefferson Medical College of Thomas Jefferson University in Philadelphia. If you have a uterus, he says, your doctor will prescribe an estrogen/progestin hormone replacement therapy.
Estrogen taken without progestin (often referred to as unopposed estrogen) causes the lining of the uterus to become too thick, which may increase the risk of cancer. Progestin helps the uterus to shed the extra lining every month. (It's exactly what used to happen during your menstrual cycle.)
Of course, a woman who has had her uterus removed doesn't have to worry about this form of cancer. She can take estrogen by itself for maximum heart protection.
Colon cancer. Hormone replacement therapy may lower your risk of colon cancer. "We think there is a strong connection between estrogen and reduced risk," says Dr. Bush. In a study of 41,070 Iowa women ages 55 through 69, researchers found lower levels of colon cancer among HRT users. In the lab estrogen prevents the "wild cell growth of cancer cells," she says. Because colon cancer cells interact with estrogen, it may help keep them from getting out of control—and stop cancers before they start to grow.
Lung cancer. "In our study we found a slightly lower than normal risk of lung cancer in women who took hormone replacement therapy," says Dr. Friedman. He emphasizes that the evidence is slight and inconclusive.
Breast cancer. "We're finding that many cancers, including breast cancer, have a strong genetic component. Estrogen may not be much of a factor," says Dr. Goldfarb. Still, if a woman is genetically at risk, it is possible that estrogen may activate the gene that gets breast cancers started, he adds. "If a patient's mother and sister had breast cancer, I would caution her that hormone replacement therapy may increase her risk," he says.
"We see a modest increase in breast cancer in women who have used hormone replacement therapy for more than five years. But the benefits appear to outweigh the risk for women who don't have close relatives who have had breast cancer," says JoAnn Manson, M.D., associate professor of medicine at the Harvard Medical School. She worked on a study that found that, after five years of hormone therapy, the average 65-year-old woman has a 3 percent chance of developing breast cancer. If she had never used hormones after menopause, the risk would have been 1.8 percent.
Researchers at Harvard University also concluded that the average woman's lifetime risk of breast cancer is 11.3 percent if she is not on hormone replacement therapy. If she is, the risk jumps to 16 percent. But her lifetime risk of developing coronary artery disease is 46 percent. HRT lowers it to about 30 percent.
| Live Better with Hormones While protection from heart disease and stroke are important reasons to think about hormone replacement therapy, these hormones are more complex and beneficial than you might think. Remember when you held down a job and balanced taking care of the house and kids? Estrogen is about that busy doing good deeds. Here is what else it can do for you and why experts recommend hormone replacement therapy for most women. Keeps your brainpower strong. Researchers think estrogen may keep your brain at its best. It may help ward off Alzheimer's disease and dementia. It also protects short-term memory. "We don't know if the protection comes from estrogen receptors in the brain and how much comes from the fact that hormone replacement therapy improves the blood flow to the brain," says Trudy Bush, Ph.D., professor of epidemiology and preventive medicine at the University of Maryland School of Medicine in Baltimore. Adding to the excitement, researchers at the University of Maryland note that a small section in rats' brains shuts down when it doesn't get estrogen. Strengthens your bones. Hormone replacement therapy protects your bones. Doctors note that it can reduce your risk of fractures caused by osteoporosis by 30 to 50 percent. Provides more zest. Some women say that they have much more pep and energy than they did before they started hormone replacement therapy, says Dr. Bush. But it's hard to know if there is a universal effect, she adds. Keeps the weight off. Researchers note that women on hormone replacement therapy tend to gain less weight as they age and retain more of their lean body mass, which is important to reduce the risk of heart disease, cancer, stroke, and diabetes. Ends incontinence. Estrogen improves bladder function because it strengthens the bladder's tissues. It also keeps the tissues in the urinary tract from atrophying. This appears to reduce urinary tract infections, says JoAnn Manson, M.D., associate professor of medicine at the Harvard Medical School. Beats the heat. Because estrogen helps regulate the body's internal clock, it keeps you from experiencing hot flashes. Even though you are well into menopause, you may still be feeling the symptoms, notes Roger Duvivier, M.D., associate professor in obstetrics and gynecology at the Albert Einstein Medical Center in New York City and author of the book Midlife, Madness, or Menopause. Fights insomnia. Hormone replacement therapy helps get rid of insomnia, a frequent side effect of menopause. Makes sex enjoyable. Hormone replacement therapy helps eliminate vaginal dryness and reduce the thinning of the vaginal walls that can make sex painful. |
Pick the Right Products
"Oral hormone replacement therapy products are the only ones that improve cholesterol levels, and they appear to give cardiovascular benefits," says Dr. Manson. "The estrogen skin patch does help protect you from osteoporosis, but we don't have evidence that it helps the heart." Neither do the vaginal ointments that help strengthen the vaginal walls to prevent dryness and discomfort during sex.
Still, if you go on hormone replacement therapy, you may get your period again, returning to your youth in the one way that you would rather not. You might also experience the side effects that used to accompany your period. Here is a breakdown of what products are available and how they will affect your system.
Unopposed estrogen therapy. If you don't have a uterus, the choice is clear: estrogen by itself. This way, you get the most heart protection and eliminate the possibility of side effects, which come from the progestin that protects the uterus from cancer.
Continuous hormone replacement therapy. If you have a uterus, you need the combination of estrogen and progestin to protect from uterine cancer. Continuous hormone replacement therapy gives you low daily doses of both estrogen and progestin.
You may get a little less heart protection than you would from estrogen alone, because progestin keeps HDL from rising as much as it would otherwise. "But the difference is modest," says Dr. Manson.
If you're lucky, you won't get a return of your period, either. "About one-third of women on continuous hormone replacement therapy don't get their periods, one-third get regular periods, and one-third experience irregular bleeding," says Dr. Bush.
It is usually worth putting up with the inconvenience, advises Dr. Manson. Irregular bleeding with continuous therapy almost always stops after six to nine months. After that, most women have no more bleeding—period.
You may also start to reexperience premenstrual symptoms such as bloating and mood changes. "There is no way of predicting whether your symptoms will be more or less than those that you had with your natural periods," says Dr. Manson.
Your body may let you know it is uneasy with the change through periodic twinges of nausea. "You probably won't throw up," says Dr. Bush. "You just may feel a little queasy at times." Some women also report tenderness and discomfort in their breasts. Most symptoms subside within three months.
If your symptoms really bother you, ask your doctor to prescribe the lowest possible dose of progestin. "You still need progestin to protect your uterus, but it is what causes most of the symptoms," says Dr. Manson. If you're on a continuous program, your doctor may be able to lower your symptoms by dropping your progestin dose to 2.5 milligrams.
Cyclic hormone therapy. If you can't tolerate the irregular bleeding that may accompany continuous hormone replacement therapy, try cyclic hormone therapy, advises Dr. Bush. On this form of therapy, you recycle your body's old reproductive routine and return to the days when you had a regular menstrual cycle. You take estrogen pills for most of the month and then switch to progestins for the remainder.
On cyclic therapy you may get the old side effects of your menstrual cycle, thanks to the progestin. If you're very uncomfortable, ask your doctor to lower your progestin dose to 5 milligrams, says Dr. Manson.
Prescription for Prevention
Hormone replacement therapy lowers bad cholesterol levels, increases good cholesterol, and appears to protect you from heart disease and stroke. It may also guard against colon cancer, although it may be linked to a slight increase in breast cancer risk. It also keeps your bones strong, helps prevent incontinence, may protect against Alzheimer's disease, and makes sex more enjoyable.
Do:
* If you have a uterus, use a combined estrogen/progestin regimen to protect against uterine cancer.
* If your uterus has been removed, use an estrogen-only product for maximum heart protection.
* Use oral products, if possible, for heart protection, not products applied to the skin.
Don't:
* Use hormone replacement therapy if you are genetically at high risk for breast cancer (if your mother or sister had it).
* Use hormone replacement without progestin if you have a uterus. It will increase your risk of uterine cancer.
