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Osteoporosis, which means “porous bones”, is a disease in which the bones become thin and brittle, and as a consequence, break easily. It affects more than 200 million women world-wide, and approximately thirty percent of women over the age of 50 have one or more vertebral fractures during their lifetime¹. But osteoporosis also affects men. One out of every five men over the age of fifty will suffer from an osteoporosis-related fracture during their lifetime². More than 1.5 million osteoporosis-related fractures occur in men and women annually³. Most fractures occur in the spine, hip and wrist, and cause suffering, disability and a diminished quality of life. In fact, according to the International Osteoporosis Foundation, twenty percent of all patients die within one year after a hip fracture⁴.

There is no single factor that causes osteoporosis, but a combination of genetic, dietary, hormonal, age-related and lifestyle factors contribute to its development⁵. Throughout childhood and the teenage years, the body develops new bone faster than existing bone is absorbed by the body. Bone mass peaks at about age thirty, then this process begins to reverse, and bone begins to be absorbed by the body faster than new bone is made. The volume of bone remains about the same, but its density decreases⁶.

Low bone mass is the most important risk factor, and therefore sufficient calcium and vitamin D intake during childhood and young adulthood is critical to reaching peak adult bone mass⁷. Other risk factors include being female, having a small-boned frame, family history of osteoporosis, early estrogen deficiency, ethnic heritage (white and Asian women are at a higher risk than African-American and Hispanic women), and advanced age⁸. Although genetics determine the maximum amount of bone mass an individual can acquire, lifestyle habits such as eating a diet rich in calcium and vitamin D, exercising regularly, refraining from tobacco use and limiting alcohol consumption can help build and maintain bone mass⁹.

Bone loss increases in women around menopause, when the ovaries decrease their production of estrogen. In men, bone loss increases when the production of testosterone decreases, at about 45 to 50 years of age¹⁰. However, since men tend to build more bone mass than women, they tend to get to osteoporosis later in life¹¹. Most people do not experience symptoms in the early stages of osteoporosis. However, as the disease progresses, symptoms such as back pain, loss of height, a curved upper back and broken bones may occur.

Osteoporosis treatment includes the lifestyle habits mentioned above (eating a diet rich in calcium and vitamin D, exercising regularly, refraining from tobacco use and limiting alcohol consumption), but can also include medication to reduce bone loss and increase bone density. Biophosphates (for example, alendronate, ibandronate and risedronate), reduce the rate of bone loss and can be taken by men and women. Raloxine, a selective estrogen receptor modulator, reduces the rate of bone thinning and produces some increase in bone thickness, but it can only be taken by women (unlike estrogen, raloxine does not cause an increased risk of endometrial cancer). Calcitonin, a hormone that regulates calcium levels in the body, slows the rate of bone loss and can be taken by men and women. Finally, parathyroid hormone can be used for men and women with severe osteoporosis¹².

Discussion questions

1. Please summarize the article. What is the main point of the article?
2. What is osteoporosis?
3. Who is affected by osteoporosis?
4. What causes osteoporosis?
5. What are the symptoms of osteoporosis?
6. What can be done to prevent osteoporosis?
7. How can osteoporosis be treated?

References:

1. International Osteoporosis Foundation. 2006. 　Accessed 25 July 2006.
2. International Osteoporosis Foundation. 2006.　Accessed 25 July 2006.
3. International Osteoporosis Foundation. 2006.　Accessed 25 July 2006.
4. International Osteoporosis Foundation. 2006.　Accessed 25 July 2006.
5. Strange, Carolyn. Boning up on osteoporosis. WebMD Public Information from the FDA.　Accessed 25 July 2006.
6. Strange, Carolyn. Boning up on osteoporosis. WebMD Public Information from the FDA.　Accessed 25 July 2006.
7. Strange, Carolyn. Boning up on osteoporosis. WebMD Public Information from the FDA.　Accessed 25 July 2006.
8. Strange, Carolyn. Boning up on osteoporosis. WebMD Public Information from the FDA.　Accessed 25 July 2006.
9. Strange, Carolyn. Boning up on osteoporosis. WebMD Public Information from the FDA.　Accessed 25 July 2006.
10. WebMD. Osteoporosis: What increases your risk.　Accessed 25 July 2006.
11. WebMD. Osteoporosis: What happens.　Accessed 25 July 2006.
12. WebMD. Osteoporosis: Medications.　Accessed 25 July 2006.