Menopause 101 By Amy Rosenman, M.D. and Nancy Greep, M.D
Introduction
Menopause occurs when the ovaries are depleted of eggs and can no longer secrete estrogen. For women with a uterus, menopause is signaled by the cessation of periods. For women who have had a hysterectomy, ovarian failure can be detected by measuring the blood level of FSH, a pituitary hormone which stimulates the ovary and whose level rises dramatically when estrogen levels decline. The average age of menopause is ~51 (range ~45-55). Since women’s life expectancy in the USA is 81 years, women can expect to spend about 1/3rd of their life in menopause.
Undisputed consequences of estrogen deficiency are vasomotor symptoms (hot flashes and night sweats), thinning of the walls of the vagina and urethra, and bone loss. Another often unappreciated consequence of estrogen deficiency is some protection against the development of breast cancer. While the risk of breast cancer increases with age, the risk rises less rapidly in women who are estrogen deficient. More controversial issues, not discussed here, are whether estrogen deficiency, especially in women who enter menopause early, increases the risk of cardiovascular disease and Alzheimer’s disease.
Hot Flashes
About 80% of women entering menopause develop hot flashes, but in most women the hot flashes gradually decline over about two years. Vasomotor symptoms can interrupt sleep and lead to daytime fatigue and irritability. Hot flashes are due to a disturbance in the part of the brain which regulates core body temperature. When a hot flash occurs, it is because the body’s thermostat has been turned down a notch. To cool down, the body diverts blood to the skin (red flush), begins to sweat, and creates the sensation of heat with the result that the woman will want to shed some clothes and fan herself. The most effective treatment for hot flashes is estrogen. Popular alternatives include low doses of certain anti-depressant medications (SSRI’s) and soy products. In addition, wearing layered clothing and avoiding hot environments and spicy foods can be helpful.
Vaginal, Urethral Symptoms
When the vaginal walls become thin and dry, some women may experience pain with intercourse. When the urethral lining thins, it may become inflamed and cause urinary frequency. Both of these syndromes are most effectively treated with estrogen, which can be given orally or intravaginally. The latter offers the advantage of not raising blood levels of estrogen. There are several options here: a vaginal ring that is changed every three months, vaginal tablets that are inserted twice a week, and a vaginal cream that is inserted 2 – 3 times per week. The cream works the fastest but the ring and tablets are easier to use. An additional option is the use of non-hormonal vaginal moisturizers or lubricants.
Bone Loss
After menopause, bone loss occurs in all women, but may be more marked in some women, for example those who are thin, smoke, or use certain medications (common offenders are thyroid and corticosteroids). Bone loss can be tracked by measuring bone density (DEXA scans of the spine and hip are the current gold standard). Over a lifetime, without preventive measures, women can lose as much as 30-40% of their bone mass. Untreated, about half of menopausal women will experience some type of osteoporotic fracture. Bone loss can be mitigated by adequate intake of calcium, vitamin D, and regular exercise. Total calcium intake should be about 1200-1500mg per day, including calcium from the diet. Most calcium in an American diet comes from milk and milk products like yoghurt and cheese. Since the average dietary intake of calcium in adult women is ~700mg, most women need a calcium supplement to meet their daily needs (500 mg once or twice a day). Adequate oral vitamin D intake is 1000-2000IU a day. Since average dietary intake of vitamin D is only 100-200IU, most women also require vitamin D supplementation, especially those who have dark skin or spend little time in the sun (the skin actually makes most of the vitamin D our bodies use). As for exercise, its main purpose exercise is not so much to increase bone density (weight bearing exercise in adults-as opposed to children-produces only minor increases in bone density), but rather to build muscular strength and balance, and thus to minimize injurious falls. Effective drugs to prevent bone loss include estrogen, Evista (a “designer estrogen”), and bisphosphonates (Fosamax, Actonel, Boniva, ReClast). The decision on whether to use one of these drugs is based on a woman’s bone density, her estimated risk of fracture, and personal preference.
Hormone Replacement Therapy (HRT)
Hormone replacement therapy (HRT) includes estrogen, and, for women who have not had a hysterectomy, some form of progesterone (a progestin). The purpose of the latter is to prevent build up of the lining of the womb (endometrium) which, if unchecked, can lead to endometrial cancer. HRT is available in many different doses and can be delivered by dif various routes (oral, skin patch, or intravaginal). In addition, there are natural and synthetic hormone preparations.
Recently, there has been controversy about the safety of HRT because some large clinical trials of oral HRT in older menopausal women showed that it was associated with a small increased risk of stroke, heart attack, breast cancer, blood clots, and dementia. These findings were more evident in older women and those who were on a combination of Premarin and a synthetic progestin (as opposed to estrogen alone). However, there is growing, but so far no conclusive evidence that if HRT is begun at the time of menopause, it might not have all these risks, and might even be protective against heart disease and cognitive decline. Nonetheless, even if this does turn out to be true, the jury is still out on the risks vs. benefits of long term use of HRT begun at the time of menopause. Consequently, the current recommendation is to take the lowest effective dose of HRT for as short a time as possible and to avoid initiating it in women well beyond their menopause.
If a woman does decide to take HRT, recent studies suggest effective regimens with fewer adverse side effects can be achieved by using lower doses, natural compounds, and non-oral routes of administration. When estrogen is taken by mouth, after it is absorbed by the gut it goes directly to the liver and causes many metabolic problems including the synthesis of clotting factors and triglycerides. Not surprisingly, oral HRT seems to predispose to blood clots while skin patch estrogen probably does not. Furthermore, both the gut and the liver metabolize estrogen into inactive or weak estrogens so that the effective oral dose is about twenty times higher than the dose given by skin patch.
Conclusion
Finally, to optimize health in the menopause, women should have a healthy lifestyle (including a nutritious diet, regular exercise, adequate sleep, and avoidance of smoking, excessive alcohol, and obesity) and a primary physician to oversee their health care. Women are advised to undergo periodic physical examinations by their primary physician, a dentist, and eye care provider. Periodic screening tests also are in order such as blood pressure, cholesterol/lipids, blood sugar, mammograms, Pap smears, bone density and colonoscopy. Finally, preventive treatments such as flu shots, other immunizations, and age appropriate health education (ex. breast self exam, fall prevention, etc.) are recommended. In the end, being informed and taking a proactive position about personal health is the best assurance for a healthy menopause.
For more information about menopause or to contact this or another physician at Saint John's Health Center visit http://www.stjohnswomens.org/ or call 1-800-STJOHNS.
