Menopause

Description

Alternative Names

Complications

After a woman reaches menopause, her average life expectancy is 30 years. During those years, however, she faces certain health risks due to lower levels of estrogen that cause accelerated bone loss and an increase in LDL cholesterol (the so-called bad cholesterol). Her risks for serious disorders are estimated at 46% for heart disease, 20% for stroke, and 15% for hip fracture. In addition, about 8% of people over 75 have dementia, with postmenopausal women having 1.4 to three times the risk for Alzheimer's disease compared to men.

Effects on the Heart

Heart disease is the number one killer of women. In 1998, more than 500,000 women died from diseases of the heart and circulation (cardiovascular diseases). Such diseases, which include heart attack and stroke, were responsible for more deaths than the next fourteen causes combined. Although young women have a much lower risk for cardiovascular disease than young men, after menopause women catch up, so that after age 51 their risk of dying of heart disease is very close to that of men. Estrogen loss is believed to play a major role in this increased risk. Estrogen has the following effects:

• Positive Effects on Cholesterol and Other Lipids (Fats in the Blood). About two years before menopause, as estrogen levels begin to decline, the levels of the harmful low-density lipoprotein (LDL) cholesterol begin to rise and the advantageous high-density lipoprotein (HDL) levels decrease.
• Positive Effect on Blood Flow. Estrogen has significant effects on smoothing, relaxing, and opening blood vessels, thereby increasing blood flow and reducing pressure.
• Antioxidant Actions. Estrogen is also an antioxidant. That is, it helps clean up particles called oxygen-free radicals that are released by natural chemical processes in the body, which can cause significant damage, including harm to the arteries.
• Mixed Effects on Blood Pressure. The effects of estrogen on blood pressure are not clear. Oral contraceptives, for instance, which contain estrogen, appear to increase pressure slightly.

Blood pressure is the force applied against the walls of the arteries as the heart pumps blood through the body. The pressure is determined by the force and amount of blood pumped and the size and flexibility of the arteries.

• Mixed Effects on Blood Clotting. Estrogen affects many blood-clotting factors in the liver: It reduces blood viscosity (stickiness) and may enhance fibrinolysis, the natural process for breaking down blood clots. Unfortunately, estrogen also has other actions that increase the risk for blood clots. Women who take hormone replacement therapy are at risk for thromboembolism -- blood clots that block a vessel.

Click the icon to see an image of thromboembolism.

• This action may explain the higher rates of adverse heart events now observed in women with heart disease who take HRT.

Effect of Menopause on Bone Density

Osteoporosis is a disease of the skeleton in which bones become brittle and prone to fracture. In other words, the bone loses density. At age 65, about 30% of women have osteoporosis, and nearly all of them are unaware of their condition. After age 80, up to 70% of women develop osteoporosis. Osteoporosis is a major risk factor for fracture in the spine and hip. The lifetime risk of spinal fracture in women is about one in three and that for hip fracture is one in six. Furthermore, between 10% and 20% of women who experience a hip fracture die within a year and about 25% require nursing home treatment.

Click the icon to see an image of osteoporosis.

Experts are still puzzled by the extreme speed-up of bone breakdown (resorption) after menopause. Estrogen may have an impact on bone density in various ways:

• Estrogen's most important effect on osteoporosis appears to be prevention of bone break down (resorption). Some research suggests that estrogen may control the life span of osteoclasts, the cells responsible for bone breakdown.
• One study reported that part of estrogen's beneficial actions may involve maintaining normal levels of vitamin D, an important nutrient in bone protection.

Risk factors for osteoporosis include:

• Being tall and thin.
• Being Caucasian.
• Smoking.
• Taking thyroid hormone.
• Being sedentary.
• Early menopause or surgical menopause (removal of ovaries).

Women at risk for osteoporosis should have a bone density test to measure their bone mass and then make a decision about treatment after consulting their physician.

Estrogen Loss and Mental Decline

Estrogen, the primary female hormone, appears to have properties that protect against the memory loss and lower mental functioning associated with normal aging. Among estrogens effects on the brain are the following:

• Laboratory studies suggested that estrogen may help block production of beta-amyloid, the source of the sticky plaques found in Alzheimer's brains.
• Estrogen may trigger the temporary growth of nerve pathways in the memory portion of the brain.
• Estrogen may stimulate production of the neurotransmitters acetylcholine and serotonin, which are depleted in Alzheimer's patients.
• Estrogen also appears to smooth, relax, and open blood vessels, which may help blood flow in the brain.
• Estrogen is also an antioxidant. That is, it helps clean up free-oxygen radicals, the unstable particles thought to play a role in Alzheimer's.
• Studies have been mixed on the association between natural estrogen levels and mental functioning in older women. For example, one 2001 study reported no association between a higher risk for dementia and a longer reproductive life in women, suggesting that longer exposure to estrogen did protect against mental decline. On the other hand, a 2002 study reported poorer mental status in women with lower levels of estrogen.

Gum Disorders and Tooth Loss

Estrogen therapy has been associated with reduced gum bleeding and with decreased bone loss around the teeth, and women who take estrogen are less likely to lose their teeth. Thus, the same principle that helps prevent bone loss in osteoporosis is also at work in preventing bone loss in the mouth.

Eye Disorders

Estrogen, progesterone, or both appear to protect against cataracts.

Click the icon to see an image of a cataract.

Studies are also indicating that estrogen helps prevent glaucoma and macular degeneration.

Click the icon to see an image of glaucoma.

Click the icon to see an image of macular degeneration.

Incontinence

The drop in body estrogen levels brought on by menopause may contribute to both stress and urge incontinence.

Wrinkles

Some evidence exists that estrogen may help prevent slackness and dryness in the skin and even reduce wrinkles.

Urinary Tract Infections

Women are at increased risk for recurrent urinary tract infections after menopause. Researchers suggest that estrogen may resist infection by increasing the number of lactobacilli, a microorganism that fights infection by preventing bacteria from adhering to vaginal cells. (Studies are finding that vaginal creams or rings containing estrogen dramatically lower the incidence of recurring infections. It is not clear whether taking oral estrogen has the same benefit. Some studies, in fact, reported a higher incidence of urinary tract infections in women taking oral estrogen.)

Sleep Disorders

Menopause is associated with more sleeping problems, including inability to fall asleep and nighttime wakefulness.