Hormone Replacement Therapy Health Article

Preventive care

HRT is recommended by many doctors on the grounds that estrogen replacement helps to protect women against two serious midlife health problems.

OSTEOPOROSIS. Osteoporosis is a disorder in which the bones become more brittle and more easily fractured. It is a particular problem for postmenopausal women because the lower levels of estrogen in the blood lead to weakening of the bone. About 25% of Caucasian women will develop severe osteoporosis; Asian women have a slightly lower risk level; Latino and African American women are least at risk.

In addition to race, there are other factors that put some women at higher risk of developing osteoporosis. Women in any of the following groups should take bone loss into account when considering HRT:

• family history of osteoporosis
• menopause before age 40
• kidney disease and dialysis
• thin body build or being underweight
• history of colitis, Crohn's disease, or chronic diarrhea
• thyroid medications
• childlessness
• chronic use of antacids
• lack of exercise
• poor food choices, including high salt intake, lack of vitamin D, high caffeine consumption, and low calcium intake
• smoking and alcohol abuse
• cortisone therapy

HEART DISEASE. Heart disease is a major health concern of women in midlife. It is the leading cause of death in women over 60. The primary disorders of the circulatory system in postmenopausal women are stroke, hypertension, and coronary artery disease. Current studies of women on HRT do not yield a completely clear picture. In particular, although estrogen given without progestins has been shown to offer some protection against heart disease, the effect of progestins in offsetting the benefits of estrogen complicates the research findings. It seems likely that estrogen levels are only part of the picture in evaluating a woman's risk of heart disease.

The major factors that are known to increase the risk of heart disease include:

• history of smoking
• being overweight
• high-fat diets
• alcohol abuse
• family history of heart disease
• high blood pressure
• high blood cholesterol levels
• diabetes.

Less important risk factors include being African American, having a sedentary lifestyle, undergoing menopause before age 45, and having high levels of family- or job-related stress.

Medical conditions

Certain groups of women should not use HRT. They include women with:

• breast cancer
• cancer of the uterus
• abnormal vaginal bleeding that has not been diagnosed
• high blood pressure that rises when HRT is used
• liver disease
• gallstones or diseases of the gallbladder

Drug interactions

HRT can interact with other prescription medications that a woman may be taking. Women who are taking corticosteroids, drugs to slow the clotting of blood (anticoagulants), and rifampin should ask their doctor about possible interactions.

Combining estrogens with certain other medicines can cause liver damage. Among the drugs that may cause liver damage when taken with estrogens are:

• acetaminophen (Tylenol), when used in high doses over long periods
• anabolic steroids such as nandrolone (Anabolin) or oxymetholone (Anadrol)
• medicine for infections
• antiseizure medicines such as divalproex (Depakote), valproic acid (Depakene), or phenytoin (Dilantin)
• antianxiety drugs, including chlorpromazine (Thorazine), prochlorperazine (Compazine), and thioridazine (Mellaril).

In addition, estrogens may interfere with the effects of bromocriptine (Parlodel), used to treat Parkinson's

disease and other conditions; they may also increase the chance of toxic side effects when taken with cyclosporine (Sandimmune), a drug that helps prevent organ transplant rejection.

Description

HRT medications come in several different forms, including tablets, stick-on patches, injections, and creams that are worn inside the vagina. The form prescribed depends on the purpose of the hormone replacement therapy. Women who want relief from vaginal dryness, for example, would be given a cream or vaginal ring. Women using HRT to relieve hot flashes or to prevent osteoporosis and heart disease often prefer oral medications or patches. All HRT medications used in the United States are available only with a doctor's prescription.