What Is Osteoporosis?
Osteoporosis means “porous bone”. If you looked at healthy bone under a microscope, you would see that parts of it look like a honeycomb. If you have osteoporosis, the holes and spaces in the honeycomb are much bigger than they are in healthy bone. This means your bones have lost density, or mass. It also means that the structure of your bone tissues has become abnormal. As your bones become less dense, they become weaker.
For some people affected by the disease, simple activities such as lifting a child, bending down to pick up a newspaper or even sneezing can cause a bone to break. Because osteoporosis is a disease of the bones, it is important to know some basics about your bones. Your bones are made up of three major components that make them both flexible and strong:
- Collagen, a protein that gives bones a flexible framework
- Calcium-phosphate mineral complexes that make bones hard and strong
- Living bone cells that remove and replace weakened sections of bone
How Bones Change and Grow
Throughout life, your skeleton loses old bone and forms new bone. Children and teenagers form new bone faster than they lose the old bone. In fact, even after they stop growing taller, young people continue to make more bone than they lose. This means their bones get denser and denser until they reach what experts call peak bone mass. This is the point when you have the greatest amount of bone you will ever have. It usually happens around age 20.
You can also think of your bones as a savings account. There is only as much bone mass in your account as you deposit. The critical years for building bone mass start before your teen years and last until around age 20.
After you reach peak bone mass, the balance between bone loss and bone formation might start to change. In other words, you may slowly start to lose more bone than you form. In midlife, bone loss usually speeds up in both men and women. For most women, bone loss increases after menopause, when estrogen levels drop sharply. In fact, in the five to seven years after menopause, women can lose up to 20 percent or more of their bone density.
Osteoporosis happens when you lose too much bone, make too little bone or both. The more bone you have at the time of peak bone mass, the better you will be protected against weak bones once bone loss begins.
- About 85-90% of adult bone mass is acquired by age 18 in girls and 20 in boys. Building strong bones during childhood and adolescence can help to prevent osteoporosis later in life.
- Together, the following five steps can optimize bone health and help prevent osteoporosis:
- Get the daily recommended amounts of calcium and vitamin D
- Engage in regular weight-bearing and muscle-strengthening exercise
- Avoid smoking and excessive alcohol
- Talk to your healthcare provider about bone health
- Have a bone density test and take medication when appropriate
- A study of disease management in a rural healthcare population demonstrated that a preventive program was able to reduce hip fractures and save money.
- Osteoporosis is a major public health threat for an estimated 44 million Americans, or 55 percent of the people 50 years of age and older.
- In the U.S. today, 10 million individuals are estimated to already have the disease and almost 34 million more are estimated to have low bone mass, placing them at increased risk for osteoporosis.
- While osteoporosis is often thought of as an older person’s disease, it can strike at any age.
Osteoporosis Prevalence: Gender
- Of the 10 million Americans estimated to have osteoporosis, eight million are women and two million are men.
- Eighty percent of those affected by osteoporosis are women.
- Twenty percent of those affected by osteoporosis are men.
Osteoporosis Prevalence: Race/Ethnicity
- Significant risk has been reported in people of all ethnic backgrounds.
- Twenty percent of non-Hispanic Caucasian and Asian women aged 50 and older are estimated to have osteoporosis, and 52 percent are estimated to have low bone mass.
- Seven percent of non-Hispanic Caucasian and Asian men aged 50 and older are estimated to have osteoporosis, and 35 percent are estimated to have low bone mass.
- Five percent of non-Hispanic black women over age 50 are estimated to have osteoporosis; an estimated additional 35 percent have low bone mass that puts them at risk of developing osteoporosis.
- Four percent of non-Hispanic black men aged 50 and older are estimated to have osteoporosis, and 19 percent are estimated to have low bone mass.
- Osteoporosis is under recognized and under-treated not only in Caucasian women, but in African-American women as well.
- Ten percent of Hispanic women aged 50 and older are estimated to have osteoporosis, and 49 percent are estimated to have low bone mass.
- Three percent of Hispanic men aged 50 and older are estimated to have osteoporosis, and 23 percent are estimated to have low bone mass.
- When compared with other ethnic/racial groups, risk is increasing most rapidly among Hispanic women.
- Experts predict that costs related to osteoporotic fractures among Hispanics will increase from an estimated $754 million in 2005 to $2 billion per year in 2025.
- People cannot feel their bones getting weaker. They may not know that they have osteoporosis until they break a bone. A person with osteoporosis can fracture a bone from a minor fall, or in serious cases, from a simple action such as a sneeze or even spontaneously.
- Vertebral (spinal) fractures may initially be felt or seen in the form of severe back pain, loss of height, or spinal deformities such as kyphosis or stooped posture. In many cases, a vertebral fracture can even occur with no pain.
- Women can lose up to 20 percent of their bone mass in the five to seven years after menopause, making them more susceptible to osteoporosis.
- Certain people are more likely to develop osteoporosis than others. Factors that increase the likelihood of developing osteoporosis and broken bones are called “risk factors.” Many of these risk factors include:
- Being female
- Older age
- Family history of osteoporosis or broken bones
- Being small and/or thin
- Certain races/ethnicities such as Caucasian, Asian, or Hispanic/Latino (although African-Americans are also at risk)
- History of broken bones
- Low sex hormones
- Low estrogen levels in women, including menopause
- Missing periods (amenorrhea)
- Low levels of testosterone and estrogen in men
- Low calcium intake
- Low vitamin D intake
- Excessive intake of protein, sodium, and caffeine
- Inactive lifestyle
- Alcohol abuse
- Certain medications such as steroid medications, some anticonvulsants, and others
- Certain diseases and conditions such as anorexia nervosa, rheumatoid arthritis, gastrointestinal diseases, and others
Who Should Get Tested?
The only sure way to determine bone density and fracture risk for osteoporosis is to have a bone mass measurement (also called bone mineral density or BMD test).
Your doctor can help you determine whether you should have a BMD test. NOF Guidelines indicate, BMD testing should be performed on:
- All women aged 65 or older, regardless of risk factors
- Younger post-menopausal women with one or more risk factors
- Post-menopausal women with fractures (to confirm diagnosis and determine disease severity)
- Estrogen-deficient women at clinical risk for osteoporosis
- Individuals with vertebral abnormalities
- Individuals receiving, or planning to receive, long-term glucocorticoid (steroid) therapy
- Individuals with primary hyperparathyroidism
- Individuals being monitored to assess the response or efficacy of an approved osteoporosis drug therapy.
There are several ways to measure bone mineral density; all are painless, noninvasive and safe and are becoming more readily available. In many testing centers you don’t even have to change into an examination robe.
The tests measure bone density in your spine, hip and/or wrist, the most common sites of fractures due to osteoporosis. Recently, bone density tests have been approved by the FDA that measure bone density in the middle finger and the heel or shinbone. Your bone density is compared to two standards, or norms, known as “age matched” and “young normal.” The age-matched reading compares your bone density to what is expected in someone of your age, sex and size. The young normal reading compares your density to the optimal peak bone density of a healthy young adult of the same sex.
The information from a bone density test enables your doctor to identify where you stand within ranges of normal and to determine whether you are at risk for fracture. In general, the lower your bone density, the higher your risk for fracture. Test results will help you and your doctor decide the best course of action for your bone health.