Osteoporosis

OSTEOPOROSIS

General Infomation
Definition: 

Osteoporosis, which means "porous bones," causes bones to become weak and brittle — so brittle that a fall or even mild stresses like bending over or coughing can cause a fracture. In many cases, bones weaken when you have low levels of calcium and other minerals in your bones.
A common result of osteoporosis is fractures — most of them occur in the spine, hip or wrist. Although it's often thought of as a women's disease, osteoporosis affects men too. And aside from people who have osteoporosis, many others have low bone density, putting them at risk of developing osteoporosis.
It's never too late — or too early — to do something about osteoporosis. You can take steps to keep bones strong and healthy throughout life.

Symptoms: 

In the early stages of bone loss, you usually have no pain or other symptoms. But once bones have been weakened by osteoporosis, you may have osteoporosis signs and symptoms that include:
• Back pain, which can be severe, as a result of a fractured or collapsed vertebra
• Loss of height over time
• A stooped posture
• Fracture of the vertebra, wrist, hip or other bone
When to see a doctor
Because osteoporosis rarely causes signs or symptoms until it's advanced, the National Osteoporosis Foundation recommends a bone density test if you are:
• A woman older than age 65 or a man older than age 70, regardless of risk factors
• A postmenopausal woman with at least one risk factor for osteoporosis
• A man between age 50 and 70 who has at least one osteoporosis risk factor
• Older than age 50 with a history of a broken bone
• Take medications, such as prednisone, aromatase inhibitors or anti-seizure drugs, that are associated with osteoporosis
• A postmenopausal woman who has recently stopped taking hormone therapy
• A woman who experienced early menopause

Causes & Complication
Causes: 

Scientists don't yet know exactly why osteoporosis occurs, but they do know that the normal bone remodeling process is disrupted.
Your bone is continuously changing — new bone is made and old bone is broken down (resorption) — a process called remodeling or bone turnover. When you're young, your body makes new bone faster than it breaks down old bone and your bone mass increases. You reach your peak bone mass around age 30. After that, bone remodeling continues, but you lose slightly more than you gain.
How likely you are to develop osteoporosis depends on how much bone mass you attained in your 20s and early 30s (peak bone mass) and how rapidly you lose it later. The higher your peak bone mass, the more bone you have "in the bank" and the less likely you are to develop osteoporosis as you age.
The strength of your bones depends on their size and density; bone density depends in part on the amount of calcium, phosphorus and other minerals bones contain. When your bones contain fewer minerals than normal, they're less strong and eventually lose their internal supporting structure.
Other factors, such as hormone levels, also affect bone density. In women, when estrogen levels drop at menopause, bone loss increases dramatically. In men, low estrogen and testosterone levels can cause a loss of bone mass.

Risk Factors: 

A number of factors can increase the likelihood that you'll develop osteoporosis — some you can change, others you cannot.
Risk factors you can change
• Low calcium intake. A lifelong lack of calcium plays a major role in the development of osteoporosis. Low calcium intake contributes to diminished bone density, early bone loss and an increased risk of fractures.
• Tobacco use. The exact role tobacco plays in osteoporosis isn't clearly understood, but researchers do know that tobacco use contributes to weak bones.
• Eating disorders. Women and men with anorexia nervosa or bulimia are at higher risk of lower bone density.
• Sedentary lifestyle. People who spend a lot of time sitting have a higher risk of osteoporosis than their more-active counterparts. Any weight-bearing exercise is beneficial for your bones, but walking, running, jumping, dancing and weightlifting seem particularly helpful for creating healthy bones.
• Excessive alcohol consumption. Regular consumption of more than two alcoholic drinks a day increases your risk of osteoporosis, possibly because alcohol can interfere with the body's ability to absorb calcium.
• Corticosteroid medications. Long-term use of corticosteroid medications, such as prednisone, cortisone, prednisolone and dexamethasone, is damaging to bone. These medications are common treatments for chronic conditions, such as asthma, rheumatoid arthritis and lupus, and you may not be able to stop taking them to lessen your risk of osteoporosis. If you need to take a steroid medication for long periods, your doctor should monitor your bone density and recommend other drugs to help prevent bone loss.
• Other medications. Long-term use of aromatase inhibitors to treat breast cancer, the antidepressant medications called selective serotonin reuptake inhibitors (SSRIs), the cancer treatment drug methotrexate, some anti-seizure medications, the acid-blocking drugs called proton pump inhibitors and aluminum-containing antacids are all associated with an increased risk of osteoporosis.
Risk factors you can't change
• Being a woman. Fractures from osteoporosis are almost twice as common in women as they are in men.
• Getting older. The older you get, the greater your risk of osteoporosis.
• Race. You're at greatest risk of osteoporosis if you're white or of Asian descent.
• Family history. Having a parent or sibling with osteoporosis puts you at greater risk, especially if you also have a family history of fractures.
• Frame size. Men and women who are exceptionally thin (with a body mass index of 19 or less) or have small body frames tend to have a higher risk because they may have less bone mass to draw from as they age.
• Thyroid hormone. Too much thyroid hormone also can cause bone loss. This can occur either because your thyroid is overactive (hyperthyroidism) or because you take excess amounts of thyroid hormone medication to treat an underactive thyroid (hypothyroidism).
• Medical conditions and procedures that affect bone health. Stomach surgery (gastrectomy) and weight-loss surgery can affect your body's ability to absorb calcium. So can conditions such as Crohn's disease, celiac disease, hyperparathyroidism and Cushing's disease — a rare disorder in which your adrenal glands produce excessive corticosteroid hormones.

Complications: 

Fractures are the most frequent and serious complication of osteoporosis. They often occur in your spine or hip — bones that directly support your weight. Hip fractures often result from a fall. Although most people do relatively well with modern surgical treatment, hip fractures can result in disability and even death from postoperative complications, especially in older adults. Wrist fractures from falls also are common.
In some cases, spinal fractures can occur even if you haven't fallen or injured yourself. The bones in your back (vertebrae) can simply become so weakened that they begin to compress or collapse. Compression fractures can cause severe pain and require a long recovery. If you have many such fractures, you can lose height as your posture becomes stooped.

Tests
Tests and Diagnosis: 

Doctors commonly diagnose osteoporosis by measuring bone density.
Dual energy X-ray absorptiometry
The best screening test is dual energy X-ray absorptiometry (DXA). This procedure is quick, simple and gives accurate results. It measures the density of bones in your spine, hip and wrist — the areas most likely to be affected by osteoporosis — and it's used to accurately follow changes in these bones over time.
Other tests that can accurately measure bone density include:
• Ultrasound
• Quantitative computerized tomography (CT) scanning
• Single-photon absorptiometry

Medication & Prevention
Treatments and Drugs: 

Medications
A number of medications are available to help slow bone loss and maintain bone mass, including:
• Bisphosphonates. Much like estrogen, this group of drugs can inhibit bone breakdown, preserve bone mass, and even increase bone density in your spine and hip, reducing the risk of fractures. Examples of these medications include alendronate (Fosamax), ibandronate (Boniva), risedronate (Actonel) and zoledronic acid (Reclast).
Bisphosphonates may be especially beneficial for men, young adults and people with steroid-induced osteoporosis. They're also used to prevent osteoporosis in people who require long-term steroid treatment for a disease such as asthma or arthritis.
Side effects, which can be severe, include nausea, abdominal pain, difficulty swallowing and the risk of an inflamed esophagus or esophageal ulcers. Bisphosphonates that can be taken once a week or once a month may cause fewer stomach problems. If you can't tolerate oral bisphosphonates, your doctor may recommend periodic intravenous infusions of bisphosphonate preparations.
There have also been reports of serious side effects with bisphosphonates, such as osteonecrosis of the jaw, irregular heartbeats and visual disturbances. Discuss the potentials risks and benefits of these medications with your doctor, and let your dentist know if you're taking any medications prior to any dental surgery.
• Raloxifene (Evista). This medication belongs to a class of drugs called selective estrogen receptor modulators (SERMs). Raloxifene mimics estrogen's beneficial effects on bone density in postmenopausal women, without some of the risks associated with estrogen, such as increased risk of uterine cancer and, possibly, breast cancer. Hot flashes are a common side effect of raloxifene, and you shouldn't use this drug if you have a history of blood clots. This drug isn't currently recommended for use in men, though a small study found that it may also be helpful for preserving bone density in men.
• Calcitonin. A hormone produced by your thyroid gland, calcitonin reduces bone resorption and may slow bone loss. It may also prevent spine fractures, and may even provide some pain relief from compression fractures. It's usually administered as a nasal spray and may cause nasal irritation in some people who use it, but it's also available as an injection. Because calcitonin isn't as potent as bisphosphonates, it's normally reserved for people who can't take other drugs.
• Teriparatide (Forteo). This powerful drug, an analog of parathyroid hormone, treats osteoporosis in postmenopausal women and men who are at high risk of fractures. It works by stimulating new bone growth, while other medications prevent further bone loss. Teriparatide is given once a day by injection under the skin on the thigh or abdomen. Long-term effects are still being studied, so therapy is recommended for two years or less.
Hormone therapy
Estrogen, especially when started soon after menopause, can help maintain bone density. However, the use of hormone therapy can increase your risk of blood clots, endometrial cancer, breast cancer and possibly heart disease. Because of concerns about its safety and because other treatments are available, hormone therapy is generally not a first-choice treatment anymore.
Physical therapy
In addition to medications or hormones, physical therapy programs may help you build bone strength and improve your posture, balance and muscle strength, making falls less likely.

Lifestyle and Home Remedies: 

These suggestions may help relieve symptoms and maintain your independence if you have osteoporosis:
• Maintain good posture. Good posture — which involves keeping your head held high, chin in, shoulders back, upper back flat and lower spine arched — helps you avoid stress on your spine. When you sit or drive, place a rolled towel in the small of your back. Don't lean over while reading or doing handwork. When lifting, bend at your knees, not your waist, and lift with your legs, keeping your upper back straight.
• Prevent falls. Wear low-heeled shoes with nonslip soles and check your house for electrical cords, area rugs and slippery surfaces that might cause you to trip or fall. Keep rooms brightly lit, install grab bars just inside and outside your shower door, and make sure you can get in and out of your bed easily.
• Manage pain. Discuss pain management strategies with your doctor. Don't ignore chronic pain. Left untreated, it can limit your mobility and cause even more pain.

Prevention: 

Three factors essential for keeping your bones healthy throughout your life are:
• Adequate amounts of calcium
• Adequate amounts of vitamin D
• Regular exercise
Calcium
The amount of calcium you need to stay healthy changes over your lifetime. The Institute of Medicine (IOM) recommends the following amounts of daily calcium from food and supplements:
• Up to 1 year old — 210 to 270 milligrams (mg)
• Age 1 to 3 years — 500 mg
• Age 4 to 8 years — 800 mg
• Age 9 to 18 years — 1,300 mg
• Age 19 to 50 years — 1,000 mg
• Age 51 and older — 1,200 mg
Dairy products are one, but by no means the only, source of calcium. Almonds, broccoli, spinach, cooked kale, canned salmon with the bones, sardines and soy products, such as tofu, also are rich in calcium.
If you find it difficult to get enough calcium from your diet, consider taking calcium supplements. The IOM recommends taking no more than 2,500 mg of calcium daily.
Vitamin D
Getting enough vitamin D is just as important to your bone health as getting adequate amounts of calcium. Scientists don't yet know the optimal daily dose of vitamin D, but it's safe for anyone older than 1 year to take up to 2,000 international units (IU) a day.
Experts generally recommend that adults get between 400 and 1,000 IUs daily.
Although many people get adequate amounts of vitamin D from sunlight, this may not be a good source if you live in high latitudes, if you're housebound, or if you regularly use sunscreen or you avoid the sun entirely because of the risk of skin cancer. Although vitamin D is present in oily fish, such as tuna and sardines, and in egg yolks, you probably don't eat these on a daily basis. Vitamin D supplements or calcium supplements with added vitamin D are a good alternative.
Exercise
Exercise can help you build strong bones and slow bone loss. Exercise will benefit your bones no matter when you start, but you'll gain the most benefits if you start exercising regularly when you're young and continue to exercise throughout your life. Combine strength training exercises with weight-bearing exercises. Strength training helps strengthen muscles and bones in your arms and upper spine, and weight-bearing exercises — such as walking, jogging, running, stair climbing, skipping rope, skiing and impact-producing sports — mainly affect the bones in your legs, hips and lower spine. Swimming, cycling and exercising on machines such as elliptical trainers can provide a good cardiovascular workout, but because such exercises are low impact, they're not as helpful for improving bone health as weight-bearing exercises are.
Other tips for prevention
These measures also may help you prevent bone loss:
• Don't smoke. Smoking increases bone loss, perhaps by decreasing the amount of estrogen a woman's body makes and by reducing the absorption of calcium in your intestine.
• Avoid excessive alcohol. Consuming more than two alcoholic drinks a day may decrease bone formation and reduce your body's ability to absorb calcium.

By Anonymous on 01 June 2011