Osteoporosis is the most common type of bone disease. It is the thinning of bone tissue and loss of bone density over time. Bones become less dense and fragile, and hence can break easily. It is estimated that about one out of five women over the age of 50 have osteoporosis. About half of all women over the age of 50 will have a fracture of the hip, wrist, or vertebra (bones of the spine).
Causes, incidence, and risk factors
Osteoporosis occurs when the body fails to form enough new bone, when too much old bone is reabsorbed by the body, or both. Calcium and phosphate are two minerals that are essential for normal bone formation. Throughout youth, the body uses these minerals to produce bones. If a person does not get enough calcium, or if the body does not absorb enough calcium from the diet, bone production and bone tissues may suffer.
As we age, calcium and phosphate may be reabsorbed back into the body from the bones, which makes the bone tissue weaker. This can result in brittle, fragile bones that are more prone to fractures, even without injury. Usually, the loss occurs gradually over years. Many times, a person will have a fracture before becoming aware that the disease is present (silent disease). By the time a fracture occurs, the disease is in its advanced stages and damage is severe. The leading causes of osteoporosis are a drop in oestrogen hormone in women at the time of menopause, and a drop in testosterone in men. Women over age 50 and men over age 70 have a higher risk for osteoporosis.
Other causes include:
- Being confined to bed
- Chronic rheumatoid arthritis, chronic kidney disease, eating disorders
- Taking corticosteroid for more than three months, or taking some anti-seizure drugs
- Vitamin D deficiency
White women, especially those with a family history of osteoporosis, have a greater than average risk of developing osteoporosis. Other risk factors include:
- Absence of menstrual periods for long periods of time
- Drinking a large amount of alcohol
- Family history of osteoporosis
- History of hormone treatment for prostate cancer or breast cancer
- Low body weight
- Too little calcium in the diet
There are usually no symptoms in the early stages of the disease. Symptoms occurring late in the disease include:
- Bone pain or tenderness
- Fractures with little or no trauma
- Loss of height (as much as six inches) over time
- Low back pain due to fractures of the spinal bones
- Stooped posture or kyphosis (dowager’s hump)
Signs and tests
Bone mineral density testing (specifically a densitometry or DEXA scan) can measure the quantity of bone one has, and one can then predict the risk for bone fractures in the future. In severe cases, a spine or hip X-ray may show fracture or collapse of the spinal bones. However, simple X-rays of bones are not very accurate in predicting whether someone is likely to have osteoporosis, as almost 40 per cent of bone loss is required before the osteoporotic changes are visible on the X-rays.
The goals of osteoporosis treatment are to:
- Control pain from the disease
- Slow down or stop bone loss
- Prevent bone fractures with medicines that strengthen bone
- Minimise the risk of falls that might cause fractures
There are several different treatments for osteoporosis, including lifestyle changes and a variety of medications.
Medications are used to strengthen bones when:
- Osteoporosis has been diagnosed by a bone density study.
- Osteopenia (thin bones, but not osteoporosis) has been diagnosed by a bone density study, if a bone fracture has occurred.
- Bisphosphonates: Bisphosphonates are the primary drugs used to both prevent and treat osteoporosis in postmenopausal women. They are taken on empty stomach, either daily (alendronate), weekly (risedronate), monthly (ibandronate), or yearly (zoledronic acid).
- Calcitonin: Calcitonin is a medicine that slows the rate of bone loss and relieves bone pain. It comes as a nasal spray or injection. The main side effects are nasal irritation from the spray form and nausea from the injectable form.
- Hormone replacement therapy: Oestrogen or hormone replacement therapy (HRT) is rarely used nowadays to prevent osteoporosis and is not approved to treat a woman who has already been diagnosed with the condition.
- Parathyroid hormone: Teriparatide is approved for the treatment of postmenopausal women who have severe osteoporosis and are considered at high risk for fractures. The medicine is given through daily shots underneath the skin. This can be taken by patients themselves at home, like insulin injections.
- Raloxifine: Raloxifene is used for the prevention and treatment of osteoporosis. Raloxifene can reduce the risk of spinal fractures by almost 50 per cent. However, it does not appear to prevent other fractures, including those in the hip. It may have protective effects against heart disease and breast cancer, though more studies are needed. The most serious side effect of raloxifene is a very small risk of blood clots in the leg veins (deep venous thrombosis) or in the lungs (pulmonary embolus).
There are no surgeries for treating osteoporosis itself. However, a procedure called vertebroplasty can be used to treat any small fractures in the spinal column due to osteoporosis. The procedure involves injecting a fast-hardening glue into the areas that are fractured or weak. A similar procedure, called kyphoplasty, uses balloons to widen the spaces that need the glue. The common fractures related to osteoporosis also include that of wrist, hip and ankle. These fractures may require surgery.
Medications to treat osteoporosis can help prevent fractures, but vertebrae that have already collapsed cannot be reversed. Some persons with osteoporosis become severely disabled as a result of weakened bones. Hip fractures leave about half of the patients unable to walk independently. Although osteoporosis is debilitating, it does not affect life expectancy.
- Compression fractures of the spine
- Disability caused by severely weakened bones
- Hip and wrist fractures
- Loss of ability to walk due to hip fractures
Calcium is essential for building and maintaining healthy bones. Vitamin D is also needed because it helps your body absorb calcium. Following a healthy, wellbalanced diet can help you get these and other important nutrients throughout life. A number of medications are also approved for the prevention of osteoporosis.
Stop unhealthy habits: Quit smoking, if you smoke. Also limit alcohol intake. Too much alcohol can damage your bones, as well as put you at risk for falling and breaking a bone.
Prevent falls: It is critical to prevent falls. Avoid sedating medications and remove household hazards to reduce the risk of fractures. Other ways to prevent falling include:
- Avoiding walking alone on icy days
- Use bars in the bathtub, when needed
- Wear well-fitting shoes
Take proper preventions to keep Osteoporosis at bay!