ONE. An Overview of Osteoporosis and Bone Development
What is osteoporosis and what does it look like? How does osteopenia differ from osteoporosis?
Osteoporosis is a disease in which bones become less dense, lose strength, and are more likely to break (fracture). Some people describe bones with osteoporosis as "Swiss cheese." The word osteoporosis is derived from the Greek osteo, meaning bones, and porosis, meaning with holes. Osteoporosis happens mainly to women at midlife and later, but also can happen to men and children. In children, new bone forms more quickly than it breaks down so that bone is actually growing all the time. In adults, bone goes through a constant and normal process where new bone is formed and old bone is broken down simultaneously and at relatively even rates. When more bone is lost than is being formed, osteopenia and osteoporosis develop. Figure 1 compares normal bone with osteoporotic bone.
Although the words sound somewhat alike, osteoporosis and osteopenia are a little different from one another.
Figure 1 Comparison of normal bone with osteoporosis. A. Normal bone. B. Osteoporotic bone. Courtesy of the National Association of Nurse Practitioners in Women's Health (NPWH). From Dempster DW et al. J Bone Miner Res 1986;1:15-21.
Both relate to bone loss, but the difference is in how much bone is lost. Osteopenia, like osteoporosis, means that the process of bone development has become unbalanced and the rate of bone loss exceeds the rate of new bone growth. With osteopenia, some bone has been lost but not as much as with osteoporosis. Although osteopenia increases your risk of breaking a bone, the risk is not as high as it is with osteoporosis. The word osteopenia comes from two Greek words: osteo, which literally means "bone," and penia, which means "lacking." So osteopenia is a milder version of osteoporosis but is still very important to your understanding of bone health. Many people with osteopenia will go on to develop osteoporosis. Some clinicians prefer to use the term "low bone mass" instead of osteopenia.
Why is it important to know about osteoporosis and osteopenia?
Osteoporosis is the most common bone disease. While osteoporosis and osteopenia are painless, it is still important for you to understand how they affect your personal health, family, finances, and lifestyle. A recent report from the U.S. Surgeon General says that by 2020, half of all Americans over the age of 50 will be at risk for fractures as a result of osteoporosis. Current estimates indicate that osteoporosis is an expensive healthcare problem, costing Americans $18 billion per year.
Osteoporosis is costly not only in dollars and cents, but also in terms of poor health, disability, and social isolation. Fractures that result from osteoporosis can be devastating. Up to 20% of those who fracture a hip will die within 1 year of the fracture.
Figure 2 Impact of osteoporosis. Courtesy of the U.S. Department of Health and Human Services, The 2004 Surgeon General's Report on Bone Health and Osteoporosis. What it means to you. Washington, DC: Office of the Surgeon General; 2004.
Of those who survive, 50% will not be able to return to independent living. Those who suffer fractures as a result of osteoporosis may not be able to dress themselves or carry on other activities of daily living, frequently causing depression and isolation from others. About 20% will need nursing home or assisted living care after a hip fracture because they are not able to live independently. Figure 2 shows the impact of poor bone health and why it's important for you to be aware of osteoporosis.
-  In Greek, literally meaning bones (osteo) with holes (porosis); a disease in which bones become less dense, lose strength, and are more likely to break (fracture).
-  To break, splinter, or crack a bone.
-  In Greek, literally meaning bone (osteo) that is lacking (penia); the process of bone development has become unbalanced and the rate of bone loss exceeds the rate of new bone growth. With osteopenia, some bone has been lost but not as much as with osteoporosis.
-  A physical or mental impairment that causes inability to perform normal or routine activities.