One of the most serious consequences of postmenopausal aging is the development of osteoporosis. In fact, osteoporosis is a major health problem affecting more than 25 million older Americans, 90 percent of them women. One out of three American women will develop osteoporosis, most after menopause.
The statistics surrounding osteoporosis are astounding. More than 1.3 million fractures occur each year as a result of this condition. Eighty percent of the 250,000 hip fractures in the United States each year occur in women over age 65 as a result of osteoporosis. About one-quarter of these women die within one year from complications, such as blood clots and pneumonia, caused by their convalescence. Another one-third never regain the ability to function physically or socially on their own. These women spend the rest of their lives requiring long-term care in nursing facilities. In addition to causing hip fractures, osteoporosis is also responsible for loss of bone in the jaw, gum recession (both of which are early signs of this condition), dowager’s hump, loss of height, back pain due to compression and fractures of the vertebra, and fractures of the wrist (called colles fractures by physicians).
Often these fractures occur when only mild stress is put on the bone. This can include missing a step and falling down, falling on an extended arm or lifting a heavy object. Because of the underlying weakness of the bone, fractures can also occur spontaneously without any preceding trauma. This often occurs with vertebral fractures.
This chapter will discuss what happens to bones with osteoporosis, risk factors for osteoporosis, diagnosis of osteoporosis and other structural changes associated with menopause. Finally, therapies for osteoporosis and other structural changes will be explored.
What Happens to Bones with Osteoporosis
Bones are living tissue; we are constantly forming new bone cells to add to our skeletal mass and removing old cells that are no longer useful. This simultaneous addition and subtraction of bone from our skeleton is called bone remodeling; from five to ten percent of our bone is replaced through this process every year. Bone remodeling involves two types of bone cells. Osteoblasts create new bone cells, while osteoclasts are responsible for removing old cells from the skeleton. This delicately balanced process is carefully regulated by many of the hormones in our body such as estrogen, progesterone, calcitonin and thyroid (as well as other hormones).
During the first 30 to 35 years of life, we deposit more bone in our skeleton than we lose, provided our health status is normal. In fact, our bone mass is at its peak in our 20s and begins to decrease in the mid-30s. According to peak bone mass theory, our bones reach their peak level of healthy density by the early 20s. The more healthy our bones are at this stage, the less risk of osteoporosis later in life. In the years preceding menopause, bone loss begins to exceed the addition of new bone to the skeleton. As a result, bones begin to lose important minerals such as calcium, as well as their matrix or intracellular substance. This causes a decrease in bone density as well as an increased brittleness or porousness of the bones
Initially, this process occurs very slowly, and women are not even aware that it is going on. However, with loss of hormonal support to the bones at the time of menopause, this process accelerates. The first years after the onset of menopause can be a time of rapid bone loss for many women unless they have instituted therapies that emphasize prevention. Bone is lost at the rate of one to three percent per year for five to ten years after menopause. If the process of bone loss continues unabated, osteoporosis may eventually result. Unfortunately, most women are unaware that they are losing bone during their early postmenopausal years. By the time osteoporosis becomes apparent as they begin to suffer from pain and fractures, women are already in their 60s or 70s. Older women with osteoporosis may have lost as much as 40 to 45 percent of their total bone mass.
Men also start to lose bone mass around age 40 (approximately three to five percent per decade). However, they have thicker bones to start with; men have approximately 30 percent more bone mass than women. In addition, the male hormone, testosterone, helps maintain bone mass and strength. Both estrogen in women and testosterone in men help control calcium absorption by the bones. These hormones prevent the resorption of calcium from the bones into the blood circulation where calcium can be excreted from the body. However, unlike women whose estrogen levels drop precipitously at menopause, men can maintain their testosterone levels well into old age. As a result, their bones remain thicker and stronger far longer than those of women. This translates into more osteoporosis related fractures for women than men eight times more hip fractures and ten times more wrist fractures.
Although gender and age contribute greatly to the fractures that occur in old age because of osteoporosis, these are not the only factors. Many physicians also attribute fractures in the elderly to poor balance and lack of ability to right oneself when tripping or stumbling. Many older people lack flexibility, so when they fall, they absorb a much greater shock than if they could cushion themselves effectively or right themselves quickly. As a result, hip fractures increase with age, mirroring the loss of agility that occurs for many elderly women (and men).
Risk Factors for Osteoporosis
Not all women have the same risk of developing osteoporosis. Some women maintain strong and heavy bones throughout their lives, while other women develop accelerated bone loss soon after menopause. If you suspect you are at risk of developing osteoporosis, become knowledgeable about which factors have been linked to a higher incidence of this disease. This will help you and your physician evaluate your risk when planning an optimal treatment program. These factors include racial background, family history, hormonal status, lifestyle habits and pre-existing health conditions.
Skin pigmentation appears to parallel bone mass. African-American women are less likely to develop osteoporosis than white women. In fact, women at the highest risk are small and fairskinned. These are typically women of Northern European ancestry such as Dutch, German or English background with blond, reddish or light brown hair and pale skin. Oriental women have a higher risk of developing osteoporosis, too. Even among similar groups, the risk is lower with women who have darker skin. For example, in Israel the darker skin Sephardic Jews have a lower rate of fractures than do Jewish women of European origin.
If your close female relatives suffered from osteoporosis, you have a higher risk of developing this problem. Many women have seen their mothers or grandmothers develop a dowager’s hump or become disabled after suffering a hip fracture. This can be quite upsetting for the entire family who must deal with the longterm disability.
The age at which women begin menopause and how much hormonal support they maintain during their postmenopausal years affects bone density. Women who have had a surgical menopause before age 40 with removal of their ovaries are at high risk of osteoporosis because of the abrupt withdrawal of estrogen at a young age. Similarly, women who go through an early natural menopause are at high risk. A woman going through early menopause at age 35 or 40 has as much as 10 to 15 years less estrogen protection for her bones than a woman going through menopause at age 50. Thus, the older you are when going through menopause, the more years of hormonal protection are provided for your bones.
Although obesity is a health risk for many diseases such as osteoarthritis and uterine cancer, being overweight does offer some protection against osteoporosis in postmenopausal women. This is because the fat cells produce a type of estrogen called estrone through conversion of an adrenal hormone called androstenedione. This type of estrogen provides some support for the bones once the ovarian source of estrogen has dwindled.
Women who engage in regular physical exercise and are more muscular have a lower risk of developing osteoporosis. Physical activity also helps keep women flexible and agile which reduces the likelihood of fractures. Conversely, inactivity increases your risk. Young women and men confined to bed for long periods show a decrease in bone mass.
Many nutritional factors affect your risk of developing osteoporosis, too. Women who drink more than two cups of coffee per day or large amounts of other caffeine-containing beverages such as black tea or colas, or who consume more than two alcoholic drinks per day, are at higher risk. Smokers also run a higher risk of osteoporosis. High protein or salt intake are risk factors, as is inadequate calcium intake. When you do not have an adequate intake of calcium, the body takes it from your bones to maintain a blood level necessary for various processes such as heart rhythm and blood clotting.
Pre-Existing Health Issues
Women with a history of bulimia, anorexia or malabsorption syndrome have an increased risk of poor calcium absorption or low estrogen levels (often the case in women with anorexia who do not have a body fat level high enough to produce adequate estrogen). Women who use thyroid medication, suffer from an overactive thyroid gland, or use cortisone for a variety of chronic conditions are at higher risk. This is also true of women with chronic kidney disease. All these conditions can adversely affect calcium balance in the body.
Risk Factors for Osteoporosis
- Membership in a nonblack ethnic group
- Fair, pale skin color
- Having female relatives with osteoporosis
- Early menopause (before age 40)
- Being short and thin
- High alcohol use (more than 5 ounces per day)
- High caffeine use
- Low calcium diet
- Lack of vitamin D
- High-salt diet
- High-protein diet
- Chronic diarrhea or surgical removal of stomach or small intestine
- Lactose deficiency
- Daily use of cortisone
- Use of thyroid medication (over 2 grains), Dilantin, or aluminum-containing antacids
- Uremia (kidney disease)
Diagnosis of Osteoporosis
If you are not sure about the status of your bones, excellent tests are available to evaluate the likelihood of developing osteoporosis. The tests also allow physicians to diagnose osteoporosis in the early stages before the bone loss is so severe that fractures occur. These tests include the single photon densitometer, which measures the density of the forearm; dual photon densitometer, which measures the spine or hip bone; and computerized axial tomography (also called a CAT scan), which can measure bone density in the spine. The CAT scan uses higher x-ray dosages and is a more expensive test. These tests are much more sensitive than conventional x-ray, which picks up osteoporosis only when 30 percent or more of the bone mass is lost.
You may choose to have a bone density test done if you are trying to decide whether or not to use HRT. If the tests show accelerated bone loss for your age group, you should seriously consider the use of HRT unless other major health issues contraindicate the use of hormones.
Another test for osteoporosis involves collecting a 24 hour urine sample. The laboratory then determines the ratio in the urine of calcium to a chemical called creatinine. A high calcium ratio indicates increased calcium excretion and accelerated bone loss.
Other Structural Changes Associated With Menopause
The loss of hormonal support affects not only the bones and teeth but other structural elements of the body such as the joints, muscles, body shape, skin and hair. Although bone loss may occur silently for many years, women notice changes in these other structural elements within a few years of entering menopause.
For instance, the incidence of osteoarthritis increases at the time of menopause; women who have never experienced joint pain suddenly become symptomatic. In addition, women with pre-existing arthritis find that their symptoms get worse. Many women reaching menopause complain of increased stiffness in their hands and shoulders as well as low back pain.
The lack of sex hormones also affects muscle tone. Muscles throughout the body tend to sag and lose tone after menopause. Women tend to be very conscious of pelvic muscle tone loss, as well as sagging of the facial and arm muscles. The loss of pelvic muscle tone can affect sexual pleasure and the ability to hold urine. Facial drooping can appear fairly rapidly within a year or two of menopause. This change can be a cause of distress in many women who don’t like this visible sign of aging. Other tissues, such as the breasts, lose their tone and droop more. The lack of estrogen is probably also responsible for the increase in low back and pelvic pain that women experience around this time.
Another visible sign of aging for many women after menopause is a change in body shape as the distribution of weight on the body changes. The waist and upper back get thicker, while the hips and breasts tend to lose some of their fat. The result is that the female shape changes from an hourglass figure to a pear shape. Many women find that not only does their figure shape change, but they gain weight more easily (10 to 15 pounds in the year or two following menopause isn’t unusual). This can occur no matter how diligently they diet or how much they exercise. The lack of female hormonal support plus the slowing of the metabolism are probably responsible for these changes. Women after menopause don’t burn calories as efficiently as during their younger years. Careful attention to diet and regular exercise can certainly help, but may not entirely correct, these physical changes. Examine the self help chapters in this book for more in-depth information.
The skin and hair undergo many changes after menopause due to loss of estrogen. There is a gradual tendency toward thinning and dryness of the skin. Skin pigmentation becomes uneven which affects coloration. Some women may lose their even skin tone and notice patches of lighter and darker skin. As collagen production in the skin slows down, the skin loses its elasticity. The underlying muscle and fat tissues that help give skin its underlying support begin to shrink. There is also a reduction in sweat gland activity and decreased tolerance to temperature changes. As a result, many visible signs of skin aging become apparent such as pronounced wrinkling and creasing. Many women find these changes cosmetically unappealing and employ a variety of dermatologic aids in an attempt to make their skin look younger and healthier.
Women who smoke, have poor nutritional habits or have had excessive exposure to sunlight are more likely to show signs of skin aging at a younger age. Conversely, women who tend to carry a little extra weight or have reached menopause at a later age will have better looking skin. This is because they have had higher circulating levels of estrogen in their bodies for more years than a thin woman who enters menopause at an early age.
Lack of estrogen also affects the hair. With menopause, hair on the head and in the pubic area becomes drier, coarser and sparser. Women may also notice the growth of darker or coarser hair in areas where they’ve never had hair before, such as the chin, upper lip, chest or abdomen. This unusual growth of hair is due to the stimulation of the hair follicle by low amounts of androgens, a type of male hormone. High estrogen levels block the action of these male hormones on hair follicle receptors. However, after menopause, these low amounts of androgen may not decrease to the same extent that estrogen does in certain women. These unopposed androgens can then affect the pattern of hair growth and hair loss, taking on a more malelike pattern.
Therapies for Osteoporosis and Other Structural Changes
Osteoporosis and other age related changes in the joints, muscles, skin and hair can be treated through the use of HRT. Other medications and supportive measures may also play a useful supporting role for certain conditions.
Hormone Replacement Therapy
Medical studies show that hormonal therapy not only helps prevent osteoporosis but also protects women against further bone loss. Both estrogen and progestins by themselves are protective, but used together they may provide benefits exceeding the use of either hormone alone. A Danish study done in 1991 showed that a combination of estrogen and a progestogen, given no later than three years after the onset of menopause, completely prevented bone loss in 18 women. In contrast, untreated women suffered significant bone loss.
Hormonal replacement therapy with conjugated estrogens (Premarin) at a dose of 0.625 mg per day has been shown to prevent osteoporosis in 90 percent of postmenopausal women who had no pre-existing osteoporosis. However, in one study done by Dr. Bruce Ettenger, even minimal estrogen supplementation (0.3 mg) prevented bone loss. If osteoporosis is already present, then a high dosage of estrogen is utilized, normally 1.25 to 2.5 mg per day. The estrogen oral tablet and transdermal patch appear to be equally effective in preventing bone loss. The vaginal cream should not be used for this purpose because absorption into the bloodstream may be erratic.
Various studies comparing women using estrogen with control women not on ERT showed significant differences in bone health. In one study done in Scotland by Dr. Robert Lindsay, women on ERT maintained their normal stature, while control women had a significant loss of height. Another study of 1,000 women treated with ERT for 15 years found a 70 percent reduction in wrist fractures from the expected rate. Even more striking was the observation that no hip fractures were seen in these women over the same 15 year period. A study was done at the Mayo Clinic comparing vertebral fracture rate in postmenopausal women treated with various combinations of estrogen, calcium and sodium fluoride. The group utilizing ERT had, by far, the lowest rate of vertebral fractures.
Estrogen appears to protect the bones through several mechanisms. Estrogen reduces urinary calcium and hydroxy-proline excretion which suggests it inhibits osteoclast function, the cells that break down bone tissue. Current research suggests that estrogen may even have a stimulatory effect on osteoblast cells, the cells that build up new bone. Estrogen also facilitates calcium absorption from the intestinal tract and increases parathyroid hormone and calcitonin production. The parathyroid hormone facilitates calcium absorption, while calcitonin stimulates bone formation. Estrogen appears to be critical to bone remodeling; therefore, it may well be the most essential component of prevention for osteoporosis.
The question of how long to stay on ERT is an important one for many women. Although the research data on this issue is not yet definitive, women who want to protect their bones from developing osteoporosis should consider using ERT at least ten years, possibly for life. Ideally, estrogen should be started within three years of the last menstrual period. Women already showing accelerated bone loss and considered at high risk for osteoporosis should probably make a lifetime commitment to ERT.
The longer you use ERT, the more protection your bones will have. As soon as you stop using it, your bones will begin to show signs of calcium loss and bone aging. It is never too late to begin estrogen therapy. Women in their 80s and 90s who had preexisting osteoporosis showed some benefit after starting estrogen therapy. According to one recent study, supplemental hormones benefited women 15 years after initial diagnosis of osteoporosis. In another study, estrogen therapy increased vertebral bone mass and bone density at the femoral head. Interestingly, the best response was in women farthest away from menopause who had the lowest bone mass.
The addition of a progestin to the estrogen therapy may provide even better benefits. Though estrogen alone helps protect against calcium loss, at least eight medical studies suggest that the use of estrogen and a progestin in combination has the additional benefit of increasing bone mass by promoting new bone formulation. Recent research has led to the conclusion that progesterone acts directly to stimulate new bone by attaching to the osteoblast cell receptors. Progesterone also appears to increase bone turnover. Animal studies found that bone volume was greater in animals receiving both hormones than those who received only estrogen.
One study followed women using cyclic estrogen progestin and women receiving a placebo for a ten-year period. Women who began the combined therapy within three years of entering menopause showed an increase in bone density throughout the entire study period. Women who began HRT later than three years following the onset of menopause showed some demineralization but much less than the placebo group. This study underlines the importance of beginning HRT in the early stages of menopause.
Another study compared the effects of estrogen therapy alone with combined estrogen progestin therapy on the metabolic parameters of bone. This included measurements of the blood level and the urinary calcium/creatinine ratio. All values decreased (indicating decreased calcium excretion) with the use of estrogen. The addition of a progestin, however, decreased these values even more, showing substantial bone protection.
In addition to protecting bone, HRT has been shown to help reduce symptoms of osteoarthritis. As mentioned earlier, joint pain tends to become worse in early menopause. Many women with muscle and joint pain, including low back and pelvic pain, note relief of these symptoms within two weeks of beginning HRT. As an additional side benefit, HRT may provide protection against developing rheumatoid arthritis. Reported in the Journal of the American Medical Association, one study found that there was a greater than three-fold reduced incidence of rheumatoid arthritis in 1,000 women who had taken HRT compared with those who had not taken HRT.
HRT may also benefit postmenopausal women suffering from loss of muscle tone and firmness. If these effects are particularly pronounced in the pelvic area, urinary incontinence or uterine, bladder or urethral prolapse may result. HRT helps restore muscle tone and may relieve mild symptoms of incontinence and prolapse. However, women with severe cases may still require more drastic therapy, such as surgery. As mentioned earlier, muscle pain may accompany joint pain, particularly in the low back. HRT may help relieve more generalized muscle aches and pains, too.
Although estrogen will not restore skin to its youthful appearance, it can have a significant impact on skin quality. Women on estrogen therapy usually have thicker, oilier, moister and firmer skin. ERT improves subcutaneous fat deposition, which makes the skin tighter, and collagen turnover, which thickens and firms up the skin. Estrogen also increases fluid retention in the skin, making it look moister and plumper. However, to improve skin condition estrogen should be started soon after entering menopause because it cannot completely reverse any significant skin damage that has already occurred.
ERT does not have quite as dramatic an effect on the hair, but it will balance the androgen levels in the body again. As a result, unwanted hair on chin, chest and abdomen will stop growing. Once a woman has started ERT, these hairs can be pulled out and will not regrow as long as estrogen therapy continues.
Other Therapies for Healthy Bones
Other drugs have been used besides HRT to prevent bone loss and protect against the development of osteoporosis. Some therapies have been found more effective than others.
Fluoride has been studied as a preventive therapy for osteoporosis with mixed results. On the positive side, people living in areas in which the water has a high-fluoride content have higher average bone density than people living in a low fluoride area. However, according to studies done using supplemental fluoride therapy in postmenopausal women, different types of bone show unequal changes in response to fluoride. A study done by the Mayo Clinic found that fluoride therapy increases bone density in one type of bone, called trabecular bone, but decreases cortical bone density. This may increase skeletal fragility and increase the risk of hip fractures. As a result of this study, the Mayo Clinic abandoned the use of fluoride therapy. Fluoride therapy may also cause other side effects such as anemia and intestinal disturbances.
Etidronate Disodium (Didronel)
Didronel has been used to treat women with osteoporosis who are at high risk of developing vertebral fractures and deformity. This drug coats the bone cells and specifically helps to prevent further bone loss in the spine. It has even been found to reverse some of the spinal damage that osteoporosis causes. Etidronate does not appear, however, to reverse damage in the hips, femur and other bones. In addition, some studies indicate that women who took this drug experience a higher rate of fractures than those who did not. However, this drug is continuing to be studied. Etidronate is usually administered daily for two weeks, followed by daily calcium supplementation for ten to twelve weeks. The treatment regimen is repeated every three months.
Other Supportive Measures
Besides the use of HRT and drugs, there are many actions a woman can take to prevent damage to her bones, joints, muscles, skin and hair after menopause. Healthy lifestyle habits can slow down the aging of all these bones and tissues, helping them remain healthy and at peak function. These beneficial measures include the following.
- Do regular weight bearing exercise, such as walking or weight training, at least thirty minutes per day. This helps keep bones strong and intact and promotes good blood circulation.
- Practice yoga or other stretching exercises to keep your joints and muscles limber and flexible.
- Limit cigarette use and alcohol intake.
- Avoid sun exposure unless you use a high SPF sunscreen (15 or more). The sun causes damage and aging of the skin if protection from its rays is not used regularly.
- Drink lots of water at least eight glasses per day—to thoroughly hydrate your skin and other tissues.
- Apply moisturizers to your skin to help lock in the fluid.
- Lose weight slowly if you diet. Rapid weight loss can accelerate the aging of your skin’s appearance.
- Avoid overprocessing your hair with permanents and other hair care techniques that can cause excessive dryness and splitting of the hair.
- If you want to have unwanted hair removed, consider electrolysis. This is the only permanent method for hair removal. It is important, however, to work with an experienced and knowledgeable operator. Your health care practitioner can probably recommend an operator in your community.
Structural Components of the Body that Show Menopausal Changes
Treatment Options for Osteoporosis
- Hormone replacement therapy
- Estrogen-progestin combinations
- Sodium fluoride
- Etidronate Disodium (Didronel)
- Sodium fluoride
- General supportive measures