American women are four times more likely than men to develop osteoporosis. Get the facts on prevention and treatment.

It was a Monday evening after a busy day at work in early December. I hurriedly changed into a Christmas outfit colorful enough to be a gaudy ornament on the living room tree. Just before leaving for a holiday party, I looked out of the garage to see that the light mist that had been falling all day had continued. I quickly put out the trash and was on my way. Grabbing both trash cans, I headed down the slight slope of the hill to the curb. Halfway there both feet slid out from under me and I fell back catching myself on my wrists. My first thought as I sat disheveled on the driveway was, “Oh my goodness, I hope I didn’t scuff my new blue loafers.” Struggling to my feet, I made my way back to the garage realizing that something was amiss. Both my wrists seemed to be broken.

The rest of the evening is a blur—emergency department visit, midnight surgery to set bones, and waking the next morning to find one arm in a hard cast and the other filled with enough pins to set off a metal detector. Having both wrists broken makes it difficult to brush your teeth, cut up your food, and pull up your pants. My marriage survived the eight weeks it took to recover, but we both still chuckle at the moment when my husband said, “That’s it. I draw the line. I won’t shave your legs!”

Once healed—and cast and pins removed—my family doctor insisted on a bone scan, believing that even a hard fall should not have been enough to break all four wrist bones at once. He was right. The scan showed early signs of bone loss and high risk for osteoporosis.

Osteoporosis? I was shocked. This was something that happened to my mother—not me. It was a wake-up call to realize the risk factors—genetics, small, slight frame, race, menopausal status, and age—had added up and I hadn’t escaped.

Definition and the Numbers
So what is this disease? Osteoporosis is a chronic, progressive disease characterized by reduced bone strength and increased vulnerability to fractures secondary to minor or no trauma. The disease is highly prevalent, affecting approximately one-third of women aged 60 to 70, and two-thirds of those aged 80 and older—roughly 200 million women worldwide. American women are four times more likely to develop osteoporosis than men. However, in the last few years, the problem of osteoporosis in men has been recognized as an important health concern, particularly as the number of men living over the age of 70 continues to climb. One of every two women and one in eight men over the age of 50 will have an osteoporosis-related fracture in his or her lifetime. Approximately 1.5 million osteoporosis-related fractures occur each year in the United States, costing an approximate $15 billion annually.

The development of osteoporosis is attributed primarily to three factors—accelerated bone loss at menopause in women or as men and women age, suboptimal bone growth during childhood and adolescence resulting in failure to reach peak bone mass, and bone loss secondary to disease conditions, eating disorders, or certain medications and medical treatments.

Osteoporosis is often asymptomatic until fractures occur. Resulting fractures can have a profound impact on quality of life and are associated with disability, deformity, persistent pain, immobility, and, sometimes, premature death. It is estimated that in Europe and the United States combined, more than 650,000 individuals have hip fractures each year. Of all fractures, hip fractures have the greatest physical and financial impact. It is sobering to realize that up to 20% of individuals die in the year following a hip fracture.1 Fifty percent of people experiencing a hip fracture will be unable to walk without assistance and 28% will require long-term care.

Risk Factors
There is a clear genetic predisposition to attainment of peak bone mass, which typically occurs in a person’s mid-20s. Peak bone mass is lower in individuals who have a family history of osteoporosis.2 Some bone loss is inevitable with age and menopause; however, the rate of loss varies widely among individuals. In addition to genetics, other risk factors for osteoporosis include the following:

• Age: The older you are, the greater your risk of osteoporosis. Your bones become weaker and less dense as you age.

• Gender: Your chances of developing osteoporosis are greater if you are a woman. Women have less bone tissue and lose bone more rapidly than men because of changes involved in menopause.

• Race: Caucasian and Asian women are more likely to develop osteoporosis. Nonetheless, African American and Hispanic women are at significant risk for developing the disease.

• Bone Structure and Body Weight: Small-boned and thin women (under 127 pounds) are at greater risk.

• Menopause/Menstrual History: Normal or early menopause (either natural or because of surgery) increases risk of developing osteoporosis. In addition, women who stop menstruating before menopause because of conditions related to an eating disorder such as anorexia or bulimia, or because of excessive physical exercise, may also lose bone tissue and develop an increased risk of osteoporosis.

• Lifestyle: Cigarette smoking, excessive alcohol consumption, inadequate consumption of calcium, or getting little or no weight-bearing exercise increases the risk of developing osteoporosis.

• Medications/Chronic Diseases: Certain medications used in the treatment of chronic diseases may also increase the risk of osteoporosis. Medications to treat disorders such as rheumatoid arthritis, endocrine disorders (eg, an underactive thyroid), seizure disorders, and gastrointestinal diseases may have side effects that can damage bone and lead to osteoporosis. In particular, one class of drugs that has particularly damaging effects on the skeleton is glucocorticoids.3

A Bit About Bone
To better understand osteoporosis, it is helpful to better understand bone. Bone is living, growing tissue made primarily of collagen, a protein that provides a soft framework, and calcium phosphate, a mineral that adds strength and hardens the framework. This combination of collagen and calcium makes bones strong and flexible to withstand stress. Two types of bone are found in the body: cortical and trabecular. Cortical bone is dense and compact and forms the outer layer of the bones. Trabecular bone makes up the interior of bone and has a spongy, honeycomblike structure. Throughout our lifespan, bone is constantly renewed through a process called remodeling. This process has two parts: resorption and formation. During the resorption stage, bone tissue is dismantled and removed by osteoclast cells. The next stage—bone formation—is conducted by osteoblasts, which lay down new bone tissue to replace the old. Osteoclast and osteoblast function is regulated by several hormones, including calcitonin, parathyroid hormone, vitamin D, estrogen (in women), and testosterone (in men), among others.

During the bone formative childhood and teenage years, new bone is added to the skeleton faster than old bone is removed. As a result, bones become larger and more dense. Bone formation continues at a faster pace than removal until the peak bone mass is reached somewhere between the mid-20s and the age of 30. After the age of 30, resorption of bone begins to exceed its formation. Bone loss prevention becomes key.

Keys to Prevention
The National Osteoporosis Foundation notes that there are five keys to bone health and osteoporosis prevention:

• Get the daily recommended amounts of calcium and vitamin D.

• Engage in regular weight-bearing exercise.

• Avoid smoking and excessive alcohol consumption.

• Talk to healthcare providers about bone health.

• Have a bone density test and take medication when appropriate.

Calcium and Vitamin D
Vitamin D and calcium are essential components for the prevention and treatment of osteoporosis. Substantial evidence shows that optimal calcium intake can help reduce bone loss and suppress bone turnover.4 National nutrition surveys have shown that many women and young girls consume less than one-half of the amount of calcium recommended to grow and maintain healthy bones.

Optimal calcium intake should be obtained with a diet high in fruits and vegetables and low in saturated fat and salt. The mention of fruits and vegetables in a discussion regarding optimal calcium intake may come as a surprise. A variety of population-based studies have demonstrated a beneficial effect of fruit and vegetable/potassium intake on markers of bone health in both adolescents and premenopausal and postmenopausal women.5 Additional support for a positive link between fruit and vegetable intake and bone health comes from the results of the DASH (Dietary Approaches to Stop Hypertension) and DASH-Sodium intervention trials.6,7 Of particular interest were findings that increasing fruit and vegetable intake (and controlling sodium intake) decreased urinary calcium excretion. Depending on age, an appropriate calcium intake falls between 1,000 and 1,300 milligrams per day.

Inadequate vitamin D is associated with increased bone turnover and loss. When in short supply, calcium absorption is impaired and there is a compensatory increase in parathyroid hormone (PTH) levels with resulting increased bone resorption and accelerated bone loss. Sources of vitamin D are limited and include oily fish, egg yolks, and fortified dairy products, as well as synthesis in skin from exposure to ultraviolet light. Multiple factors can contribute to inadequate serum levels of vitamin D and include dietary deficiencies, reduced intestinal absorption, and low endogenous vitamin D synthesis due to minimal exposure to sunlight. It is not surprising, therefore, that a high prevalence of inadequate vitamin D has been documented in a variety of studies worldwide and found to be especially common among older adults.1 Supplementation may be necessary to obtain adequate vitamin D. The Institute of Medicine Adequate Intake (AI) for the United States and Canada is 400 international units daily for people aged 70 and under, and 600 international units daily for those over the age of 70.8 The FDA Daily Value recommendation for vitamin D is 400 international units regardless of age.

Exercise
Exercise is an important component of good bone health. Regular exercise during childhood and adolescence promotes attainment of peak bone mass. A lack of exercise, especially as a person ages, may contribute to lower bone mass or density. An analysis of exercise programs indicates that exercisers can gain approximately 1% bone mineral density vs. nonexercisers over one year.9 If that bone density effect continued each year, exercise could ultimately produce substantial effects on bone mineral density.

Bone Scans
Since osteoporosis can develop undetected for decades, early diagnosis is important. The only way to accurately diagnose osteoporosis and predict the risk for future fractures is to measure bone density. Bone mass should be measured when the individual is considered to be at increased risk of osteoporosis and/or may be a candidate for treatment. Guidelines developed by the National Osteoporosis Foundation suggest that all women have a bone density measurement by the age of 65 because age alone is such an important risk factor for osteoporosis. Bone density testing should be performed in younger women at the time of menopause if they have risk factors such as prior history of fracture, low body weight, smoking, and/or the presence of underlying diseases or use of medications known to increase the risk for osteoporosis.

Medical Treatment
For individuals at high risk of fracture, medical treatment may be recommended. A variety of medications are currently approved and include alendronate (Fosamax), risedronate (Actonel), and raloxifene (Evista) for prevention and treatment of osteoporosis; teriparatide (Forteo) and nasal calcitonin spray (Miacalcin) for treatment only; and estrogens or combinations of hormones (hormone replacement therapy) for prevention only. In all cases, regular monitoring of the treatment effectiveness should be conducted.

The Future
The future will bring more medical treatments, including “designer” selective estrogen receptor modulators, as well as other antiresorptive agents. New nonmedical approaches will help reduce the impact of falls and reduce the incidence of falls themselves. Improved diagnostic measures will become more widespread and will help identify the best candidates for osteoporosis medications.

— Mary Kaye Sawyer-Morse, PhD, RD, is a professional speaker, author, and wellness expert. She is owner and education director of The Center for Success, a Texas-based company that provides keynotes, in-service training, and seminars to diverse industries.

Resources
International Osteoporosis Foundation
www.osteofound.org

National Institute of Arthritis and Musculoskeletal and Skin Diseases
www.niams.nih.gov

National Osteoporosis Foundation
www.nof.org

References
1. Reginster JY. High prevalence of inadequate serum vitamin D levels and implications for bone health. Curr Med Res Opin. 2005;21(4):579-585.

2. Fox KM, Cummings SR, Stone K. Family history and risk of osteoporotic fracture. The Study of Osteoporotic Fractures Research Group. Osteoporos Int. 1998;8(6):557-562.

3. NIH Consensus Development Panel on Osteoporosis Prevention, Diagnosis, and Therapy. Osteoporosis prevention, diagnosis and therapy. JAMA. 2001;285:320-323.

4. Cadogan J, Eastell R, Jones N, et al. Milk intake and bone mineral acquisition in adolescent girls: Randomized controlled intervention trial. BMJ. 1997;315(7118):1255-1260.

5. New SA. The role of the skeleton in acid-base homeostasis. The 2001 Nutrition Society Medal Lecture. Proc Nutr Soc. 2002;61(2):151-164.

6. Appel LJ, Moore TJ, Obarzanek E. A clinical trial of the effects of dietary patterns on blood pressure. N Engl J Med. 1997;336:1117-1124.

7. Lin P, Ginty F, Appel L. Impact of sodium intake and dietary patterns on biochemical markers of bone and calcium metabolism. J Bone Miner Res. 2001;16(S1):S511.

8. Standing Committee on the Scientific Evaluation of Dietary Reference Intakes Food and Nutrition Board Institute of Medicine 1997. Vitamin D. In: Dietary Reference Intakes for Calcium, Phosphorus, Magnesium, Vitamin D, and Fluoride. Washington, D.C.: National Academy Press; 1999:250-287.

9. Wallace BA, Cumming RG. Systematic review of randomized trials of the effect of exercise on bone mass in pre- and postmenopausal women. Calcif Tissue Int. 2000;67(1):10-18.

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