Osteoporosis

One of the most important health issues for middle-aged women is the threat of osteoporosis. It is a condition in which bones become thin, fragile, and highly prone to fracture. Numerous studies over the past 10 years have linked estrogen insufficiency to this gradual, yet debilitating disease. In fact, osteoporosis is more closely related to menopause than to a woman's chronological age.

Bones are not inert. They are made up of healthy, living tissue which continuously performs two processes: breakdown and formation of new bone tissue. The two are closely linked. If breakdown exceeds formation, bone tissue is lost and bones become thin and brittle. Gradually and without discomfort, bone loss leads to a weakened skeleton incapable of supporting normal daily activities.

Each year about 500,000 American women will fracture a vertebrae, the bones that make up the spine, and about 300,000 will fracture a hip. Nationwide, treatment for osteoporotic fractures costs up to $10 billion per year, with hip fractures the most expensive. Vertebral fractures lead to curvature of the spine, loss of height, and pain. A severe hip fracture is painful and recovery may involve a long period of bed rest. Between 12 and 20 percent of those who suffer a hip fracture do not survive the 6 months after the fracture. At least half of those who do survive require help in performing daily living activities, and 15 to 25 percent will need to enter a long-term care facility. Older patients are rarely given the chance for full rehabilitation after a fall. However, with adequate time and care provided in rehabilitation, many people can regain their independence and return to their previous activities.

For osteoporosis, researchers believe that an ounce of prevention is worth a pound of cure. The condition of an older woman's skeleton depends on two things: the peak amount of bone attained before menopause and the rate of the bone loss thereafter. Hereditary factors are important in determining peak bone mass. For instance, studies show that black women attain a greater spinal mass and therefore have fewer osteoporotic fractures than white women. Other factors that help increase bone mass include adequate intake of dietary calcium and vitamin D, particularly in young children prior to puberty; exposure to sunlight; and physical exercise. These elements also help slow the rate of bone loss. Certain other physiological stresses can quicken bone loss, such as pregnancy, nursing, and immobility. The biggest culprit in the process of bone loss is estrogen deficiency. Bone loss quickens during perimenopause, the transitional phase when estrogen levels drop significantly.

Doctors believe the best strategy for osteoporosis is prevention because currently available treatments only halt bone loss--they don't rebuild the bone. However, researchers are hopeful that in the future, bone loss will be reversible. Building up your reserves of bone before you start to lose it during perimenopause helps bank against future losses. The most effective therapy against osteoporosis available today for postmenopausal women is estrogen (see Managing Menopause). Remarkably, estrogen saves more bone tissue than even very large daily doses of calcium. Estrogen is not a panacea, however. While it is a boon for the bones, it also affects all other tissues and organs in the body, and not always positively. Its impact on the other areas of the body must be considered.

Cardiovascular Disease

Most people picture an older, overweight man when they think of a likely candidate for cardiovascular disease (CVD). But men are only half the story. Heart disease is the number one killer of American women and is responsible for half of all the deaths of women over age 50. Ironically, in past years women were rarely included in clinical heart studies, but finally physicians have realized that it is as much a woman's disease as a man's.

CVDs are disorders of the heart and circulatory system. They include thickening of the arteries (atherosclerosis) that serve the heart and limbs, high blood pressure, angina, and stroke. For reasons unknown, estrogen helps protect women against CVD during the childbearing years. This is true even when they have the same risk factors as men, including smoking, high blood cholesterol levels, and a family history of heart disease. But the protection is temporary. After menopause, the incidence of CVD increases, with each passing year posing a greater risk. The good news, though, is that CVD can be prevented or at least reduced by early recognition, lifestyle changes and, many physicians believe, hormone replacement therapy.

Menopause

Menopause brings changes in the level of fats in a woman's blood. These fats, called lipids, are used as a source of fuel for all cells. The amount of lipids per unit of blood determines a person's cholesterol count. There are two components of cholesterol: high density lipoprotein (HDL) cholesterol, which is associated with a beneficial, cleansing effect in the bloodstream, and low density lipoprotein (LDL) cholesterol, which encourages fat to accumulate on the walls of arteries and eventually clog them. To remember the difference, think of the H in HDL as the healthy cholesterol, and the L in LDL as lethal. LDL cholesterol appears to increase while HDL decreases in postmenopausal women as a direct result of estrogen deficiency. Elevated LDL and total cholesterol can lead to stroke, heart attack, and death.

Reprinted from the Archives of  US NATIONAL INSTITUTES OF HEALTH, National Institute on Aging.