Osteoporosis is a disease characterized by low bone mass and loss of bone tissue that may lead to weak and fragile bones.
Osteoporosis often was thought to be a condition that frail elderly women develop.
Eighty percent of those with osteoporosis are women.
Of people older than 50 years, 1 in 2 women and 1 in 8 men are predicted to have an osteoporosis-related fracture in their lifetime.
White and Asian racial groups, however, are at a greater risk.
Osteoporosis occurs when an imbalance occurs between new bone formation and old bone resorption. The body may fail to form enough new bone, or too much old bone may be reabsorbed, or both. Two essential minerals for normal bone formation are calcium and phosphate. Throughout youth, the body uses these minerals to produce bones. If calcium intake is not sufficient or if the body does not absorb enough calcium from the diet, bone production and bone tissue may suffer.
The leading cause of osteoporosis is a lack of certain hormones, particularly estrogen in women and androgen in men. Other factors that may contribute to bone loss in this age group include inadequate intake of calcium and vitamin D, lack of weight-bearing exercise, and other age-related changes in endocrine functions (in addition to lack of estrogen).
Other conditions that may lead to osteoporosis include overuse of corticosteroids (Cushing syndrome), thyroid problems, lack of muscle use, bone cancer, certain genetic disorders, use of certain medications, and problems such as low calcium in the diet.
Women are at a greater risk than men, especially women who are thin or have a small frame, as are those of advanced age.
Women who are white or Asian, especially those with a family member with osteoporosis, have a greater risk of developing osteoporosis than other women.
Women who are postmenopausal, including those who have had early or surgically induced menopause, or abnormal or absence of menstrual periods are at greater risk.
Cigarette smoking, eating disorders such as anorexia nervosa or bulimia, low amounts of calcium in the diet, heavy alcohol consumption, inactive lifestyle, and use of certain medications, such as corticosteroids and anticonvulsants, are also risk factors.
Early in the course of the disease, osteoporosis may cause no symptoms. Later, it may cause dull pain in the bones or muscles, particularly low back pain or neck pain.
Later in the course of the disease, sharp pains may come on suddenly. It may not radiate; it may be made worse by activity that puts weight on the area, may be tender, and generally begins to subside in 1 week. Pain may linger more than 3 months.
People with osteoporosis may not even recall a fall or other trauma that might cause a broken bone, such as in the spine. Spinal compression fractures may result in loss of height with a stooped posture (called a dowager’s hump).
Fractures at other sites, commonly the hip or bones of the wrist, usually result from a fall.
Exams and Tests
The doctor will normally begin with a careful history to determine if you have osteoporosis or if you may be at risk for the disease. The doctor will also ask if you have a family history of osteoporosis or a history of previous broken bones. Based on a medical examination, the doctor may recommend a specialized test called a bone mineral density test that can measure bone density in various sites of the body.
A bone mineral density test can detect osteoporosis before a fracture occurs, and can predict future fractures.
Several different machines measure bone density. All are painless, noninvasive, and safe. They are becoming more readily available. In many testing centers, you don’t even have to change into an examination robe. Central machines may measure density in the hip, spine, and total body. Peripheral machines may measure density in the finger, wrist, kneecap, shinbone, and heel.
The DXA (dual-energy X-ray absorptiometry) measures the bone density of the spine, hip, or total body. With your clothes on, you simply lie on your back with your legs on a large block. The x-ray machine moves quickly over your lower spine and hip area.
SXA (single-energy X-ray absorptiometry) is performed with a smaller x-ray machine that measure bone density at the heel, shin bone, and kneecap. Some machines use ultrasound waves pulsing through water to measure the bone density in your heel. You place your bare foot in a waterbath and your heel fits into a footrest as sound waves pass through your ankle. This is a simple way to screen large numbers of people quickly. You might find this type of screening device at a health fair. Bone loss at the heel may mean bone loss in the spine, hip, or elsewhere in the body. If bone loss is found in this test, you might be asked to have the DXA to confirm the results and get a better picture of your bone density.
The result of the bone mineral density is compared to 2 standards, or norms, known as “age matched” and “young normal.” The age-matched reading compares your bone mineral density to what is expected of someone of your age, sex, and size. The young normal reading compares your density to the optimal peak bone density of a healthy young adult of the same sex. The information from a bone mineral density test enables the doctor to identify where you stand in relation to others your age and to young adults (which is presumed to be your maximum bone density). Scores significantly lower than “young normal” indicate you have osteoporosis and are at risk for bone fractures. The results will also help the doctor to decide the best way to manage your bone health.
Self-Care at Home
If you suspect that you have signs or symptoms of osteoporosis or have risk factors for osteoporosis, see your doctor for further evaluation and treatment.
Treatment for osteoporosis focuses on slowing down or stopping the mineral loss, increasing bone density, preventing bone fractures, and controlling the pain associated with the disease.
Diet : Young adults should be encouraged to achieve normal peak bone mass by getting enough calcium (1000 mg daily) in their diet (drinking milk or calcium-fortified orange juice and eating foods high in calcium such as salmon), performing weight-bearing exercise such as walking or aerobics (swimming is aerobic but not weight bearing), and maintaining normal body weight.
Specialists : People who have spinal, hip, or wrist fractures should be referred to a bone specialist (called an orthopedic surgeon) for further management. In addition to fracture management, these people should also be referred to a physical and occupational therapist to learn ways to exercise safely. For example, someone with spinal fractures would avoid touching their toes, doing sit-ups, or lifting heavy weights.
Exercise : Lifestyle modification should also be incorporated into your treatment. Regular exercise can reduce the likelihood of bone fractures associated with osteoporosis.
Studies show that exercises requiring muscle to pull on bones causes the bones to retain, and perhaps even gain, density.
Researchers found that women who walk a mile a day have 4-7 more years of bone in reserve than women who don’t.
Some of the recommended exercises include weight-bearing exercise, riding stationary bicycles, using rowing machines, walking, and jogging.
Before beginning any exercise program, make sure to review your plan with your doctor
Estrogen : For newly menopausal women, estrogen replacement is one way to prevent bone loss. Estrogen can slow or stop bone loss. And, if estrogen treatment begins at menopause, it can reduce the risk of hip fracture up to 50%. It may be taken orally or as a transdermal (skin) patch (for example, Vivelle, Climara, Estraderm, Esclim, Alora).
SERMs : For women who are unable to take estrogen or choose not to, selective estrogen receptor modulators (SERMs) such as raloxifene (Evista) offer an alternative
Calcium : Calcium and vitamin D are needed to increase bone mass in addition to estrogen replacement therapy.
Daily intake of 1200-1500 mg (through diet and supplements) is recommended. Take calcium supplements in doses of less than 600 mg. Your body can only absorb so much at one time. The best way may be to take one supplement with breakfast and another with dinner.
Daily intake of 600-800 IU of vitamin D is needed to increase bone mass.
Bisphosphonates: Other treatments for osteoporosis are available: alendronate, risedronate, and etidronate. These drugs slow down bone loss and in some cases actually increase bone mineral density.
If you are being treated with estrogen replacement therapy, have routine mammograms, pelvic exams, and Pap smears as recommended to monitor the possible medication side effects. If you are on non hormonal treatment, have urine and kidney function tests and routine follow-up visits with your doctor.
Building strong bones during childhood and adolescence can be the best defense against developing osteoporosis later. The average woman has acquired 98% of her skeletal mass by age 30 years.
There are 4 steps to prevent osteoporosis. No one step alone is enough to prevent osteoporosis.
- A balanced diet rich in calcium and vitamin D
- Weight-bearing exercise
- A healthy lifestyle with no smoking or excessive alcohol intake
- Medication to improve bone density when appropriate