Osteoporosis-The Silent Disease

By Becky Yates, CNM

An elderly woman walks down the street stooped over with a “hump” on her upper back. Your aunt falls over a rug and breaks her hip. Grandma is complaining that her back hurts all the time. Your aging mother tries to catch herself from falling and breaks an arm. Great-aunt Nellie seems a lot shorter than she used to be. 

What do all these scenarios have in common?  These people are experiencing the signs or outcomes of osteoporosis; a bone disease that increases one’s risk for fractures. When osteoporosis occurs, there is a decrease in the normal bone mass and a change in the actual architecture of the bone. Osteoporosis is much more common in women but may also occur in men. Prior to the actual condition of osteoporosis, there is an intermediate “stage” in bone loss called “osteopenia” which means lower bone mass than normal but not to a sufficient degree to be classified as osteoporosis. The picture at the top represents normal bone and the picture below demonstrates the bone loss of osteoporosis. 

How prevalent is this loss of bone? Over half of all Americans over the age of 50 have low bone mass. In 2002 there were 44 million people in the U.S. with osteopenia or osteoporosis; that number is expected to rise to more than 52 million by 2010. Every year, 1.5 million Americans experience an osteoporotic fracture; this represents 700,000 vertebral (spine) fractures, 300,000 hip fractures, and 250,000 wrist fractures. Because 75% of vertebral fractures produce no clinically evident signs or symptoms, many people do not even know they have had one and now have osteoporosis. Death is the worst outcome from osteoporotic fractures because 24% of women die within 1 year after a hip fracture. Quality of life is also severely impacted as 50% of individuals lose the ability to walk independently after fracturing a hip. Sadly, osteoporosis is often underdiagnosed and undertreated.  One study showed that less than 26% of patients who were hospitalized for hip fractures were treated for the underlying osteoporosis that precipitated the fracture. 

Many people do not realize that bone is “living” tissue; it is constantly being broken down and rebuilt. Conditions that cause bone to be broken down faster than it can be rebuilt will lead to significant bone loss. Peak bone mass is reached before the age of 30; one begins losing bone after that time. Understanding this fact emphasizes the importance of building the maximum amount of bone in the adolescent and early adult years; failure to do so greatly increases the development of osteoporosis in later life. Therefore, osteoporosis is a disease that really has its beginnings long before middle age arrives. 

What are the conditions that might increase one’s risk for osteoporosis and subsequent fracture? Postmenopausal women who are not on hormonal therapy are at much greater risk for the disease due to the decreased amount of estrogen which has a protective effect on bone. Postmenopausal women lose bone rapidly; 20% of one’s bone mass can be lost in the first 5-6 years after menopause.  A family history of osteoporosis or fracture before the age of 50 are also important risk factors for developing the disease. Other factors include smoking, small frame or body weight less than 127 lbs, physical inactivity, excessive alcohol use, history of eating disorders, low calcium and Vitamin D intake, lack of menstrual cycle for long periods of time, and white or Asian race. Medical conditions/treatments that increase one’s risk for osteoporosis include gastrointestinal disorders/surgery that interfere with absorption of nutrients, disorders of the thyroid and parathyroid glands, autoimmune disease, and medications like steroids (Prednisone, Cortisone), excess thyroid hormone, some seizure medications, heparin, aluminum-containing antacids, and medications that suppress estrogen production. 

How are osteopenia and osteoporosis diagnosed? Certainly if someone experiences a fracture that occurred with little associated trauma or force, osteoporosis should be suspected. However, the diagnosis of these low bone mass conditions is determined by measuring bone mineral density. There are several ways to accomplish this but the “gold standard” at his point is a procedure called DEXA which is short for dual-energy x-ray absorptiometry. A DEXA scan is a very simple, quick, and painless procedure. One simply lies on an x-ray table while a machine passes over you and evaluates the bone quality in the spine and hip areas. Bone mineral density can also be measured at the heel and forearm; however measurement at these sites does not reveal what is happening at the hip and spine nor are they used for following treatment response.  Heel and forearm measurements are less expensive than DEXA so many practitioners will start with those tests as a screening. The numbers that are calculated by the bone mineral density testing determine the diagnosis of osteoporosis or osteopenia; the scoring system is known as the T-score. A T-score above a -1.0 is normal bone; a T-score between -1.0 and -2.5 is osteopenia and below -2.5 is in the osteoporotic range.  

Once osteoporosis is diagnosed, there are several therapies utilized for treatment. Bisphosphonates are a common group of medications used for treatment; these include such drugs as Fosamax, Actonel, and Boniva. These same drugs can be used for prevention of osteoporosis in someone who already has osteopenia. Bisphosphonates keep the bone from being broken down so quickly. Evista is also a drug that prevents rapid bone breakdown; it is classified as a SERM which means it acts at certain estrogen sites in a beneficial manner but does not stimulate estrogen receptors that might produce harmful effects. Calcitonin is an inhaled drug that helps improve spine bone density and helps with the back pain associated with vertebral fractures. Another drug called Forteo is used for the treatment of osteoporosis; administration is a daily injection with a very small needle. This drug is the first one that actually builds bone rather than preventing the breakdown of bone like the previous drugs. Although there have been some changes in hormonal therapy in recent years, estrogen supplementation does help prevent bone loss; in a woman who has both menopausal symptoms and risk for bone loss, it might be a consideration. 

Equally important as the drug therapies are the non-pharmacologic therapies such as exercise and the supplementation of calcium and Vitamin D. Calcium is vital for proper mineralization of the skeletal bone. Most Americans get inadequate amounts of calcium from dietary sources; the typical diet supplies about 600 mg. Recommended intake for adolescents is 1300 mg daily, 1000 mg for young and middle-aged adults, and 1200 mg for adults over 50. Good food sources of calcium include: beans, dark green leafy vegetables, oatmeal, fish consumed with bones, low- fat dairy products like yogurt, cheese and milk; and fortified orange juice and cereals. Calcium supplements are available to augment what is obtained through diet. Many supplements contain calcium carbonate which is not well absorbed unless it is taken with food; calcium citrate can be taken on a full or empty stomach. Since there is a limit to how much calcium can be absorbed at one time, it is best to take only 500-600 mg at a time. 

The importance of Vitamin D in bone health has received a lot of attention recently. Vitamin D is important for the absorption of calcium, fall prevention, preserving muscle strength, and plays a role in preventing excessive calcium from being pulled out of the bone. Vitamin D deficiency is much more common than often recognized. Almost 50% of healthy adults over 50 are deficient in Vitamin D. A large percentage of preadolescents and adolescents have insufficient Vitamin D increasing the likelihood they will not achieve peak bone mass by the time they start losing bone. Obesity increases risk for Vitamin D deficiency; it is stored in body fat which makes it less available for use by the tissues that need it. An important source of Vitamin D is sunlight exposure; about 15 minutes of sunlight to the face, neck, hands, and arms 3-5 times per week allows the body to produce Vitamin D. The further distance that one lives from the equator, the greater the chance that sunlight exposure will be ineffective to produce enough Vitamin D especially during winter months. Food sources of Vitamin D include: oily fish (salmon and sardines), liver, egg yolks, and fortified milk, soy milk, orange juice, and cereals. Recent recommendations for Vitamin D intake have suggested 800-1000 IU per day; higher intake may be required if there is inadequate exposure to sunlight. Supplements containing the D3 form instead of the D2 are better utilized by the body; taking it with a meal that contains fat helps with absorption. Recent studies have suggested that Vitamin D may play a role in preventing certain cancers in addition to its important role in bone health. 

Exercise is extremely important in both the prevention and treatment of osteoporosis; weight-bearing activities like dancing, running, tennis, jumping rope stimulate bone growth. Walking 3 to 5 miles per week helps to prevent osteoporosis; it has been shown to decrease bone turnover and increase bone mineral density in postmenopausal women with low bone mass. In one study, walking 4 hours per week decreased risk of fracture by 41%.  Bone responds best when it is stressed which makes strength training a very effective exercise for maintaining and building bone. Dr. Miriam Nelson from Tufts University has researched exercise at it relates to bone health; her books/tapes, “Strong Women, Strong Bones” demonstrate effective exercise programs for bone health. “Exercise for Osteoporosis”, a book by Dianne Daniels, is another helpful resource about exercise and bone health. Some of the ways to perform strength training include the use of free weights, weight machines in fitness centers, and resistance bands. Even yoga can provide “stress” to the bone by using one’s own body weight in holding yoga positions. Yoga is also very helpful for improving balance which is important in fall prevention which might cause a fracture; strength training helps to prevent falls by improving muscle tone. 

As you can see, there are many factors that can contribute to one’s risk for this often “silent disease”. However, like many chronic diseases, it can be prevented or its impact lessened by identifying one’s risk and taking steps to make the necessary lifestyle changes to avoid unnecessary bone loss. Take your calcium and Vitamin D, get out there and exercise, and talk to your healthcare provider about your bone health!!