More than a million people in the U.S. take steroids or cortesteroid drugs to fight a wide range of diseases, including rheumatoid arthritis and asthma. While they may be effective at fighting certain illnesses, these medicines — known collectively as glucocorticoids — can also cause problems. The most serious is osteoporosis.
Osteoporosis from glucocorticoids use is a big problem, and it s expected to grow even bigger. In the United States, 10 million people already have osteoporosis and 18 million more have low bone mass, placing them at increased risk for the disease. While 1.5 million people already take glucocorticoids, more than 30 million Americans have diseases that could require glucocorticoid use, said Lenore Buckley, M.D., of Virginia Commonwealth Institute.
Due to major advancements in the understanding and management of this disease, the American College of Rheumatology (ACR) has issued new guidelines for the prevention and treatment of glucocorticoid-induced osteoporosis. The guidelines appeared in the July 2001 issue of Arthritis & Rheumatism, an official journal of the ACR. Buckley is one of the authors of the ACR guidelines.
Bad to the Bone Osteoporosis, or porous bone, is a disease that thins and weakens bones, causing them to break easily as a result. In our bones, special cells called osteoclasts constantly break down old tissue, as other cells — known as osteoblasts — simultaneously build new tissue to replace the bone we’ve lost.
As we age, more bone is broken down and eliminated from the body — a process called resorption — than is replaced. Glucocorticoid-induced osteoporosis causes us to lose bone faster. Bones in the hip, spine and wrist are especially vulnerable.
Glucocorticoids are taken to thwart diseases including:
- Rheumatoid arthritis
- Inflammatory bowel diseases — such as Crohn’s Disease
- Rejection of organ transplants
Glucocorticoids are also present in:
- Some antiseizure drugs
- Some sleeping pills
- Hormones used to treat endometriosis
- Some cancer drugs
- Drugs to treat an overactive thyroid gland
Susan Ott, M.D., associate professor in the Department of Medicine at the University of Washington, is especially interested in the new guidelines. Corticosteroids cause osteoporosis and fractures in a high percentage of patients, she said. Many of my patients have this form of osteoporosis. Since this kind of osteoporosis is so difficult and so devastating, I am frequently asked about it.
Glucocorticoids use can:
- Slow bone formation
- Cause greater bone resorption and urine calcium loss
- Inhibit gastrointestinal calcium absorption
- Inhibit the production of male and female sex (gonadal) hormones, causing infertility
Glucocorticoids not only slow down bone formation but also increase resorption, including elimination in urine. A number of antiresorptive agents are available to both prevent and treat glucocorticoid-induced bone loss.
In the guidelines, the authors state that anti-resorptive agents are effective in the treatment of glucocorticoid-induced bone loss. All of these agents either prevent bone loss or increase lumbar spine bone mass and maintain hipbone mass. Data are also being reviewed for therapies still under investigation, including anabolic agents such as parathyroid hormone, said Buckley.
Glucocorticoids use for a long time can inhibit the secretion of sex hormones from the pituitary gland, causing hypogonadism. Hypogonadism is the decreased or absent secretion of hormones from either the female ovaries or the male testes. It can result in infertility. Glucocorticoids can also slow hormone production by the ovary and testes.
How Can You Tell if You are Losing Bone? Losing height or having a bone break easily is often the first sign of osteoporosis. The best way to be sure, according to The National Institute on Aging (NIA), is a bone density exam. Bone density reveals how solid our bones are.
Ordinary x-rays don t show bone loss until a large amount of bone density is gone. The best way to measure bone density is by a DEXA-scan (dual-energy x-ray absorptiometry). This is done on the whole body.
The test results are reported as a number:
-2.5 SD (standard deviation) or more, means a person has osteoporosis
-1SD to -2.5SD means some bone loss. This is known as osteopenia.
ACR recommendations The new ACR guidelines include:
- New information on how glucocorticoids cause or contribute to osteoporosis
- New information on glucocorticoid use as a risk factor for fractures
- Treatment strategies for this type of osteoporosis including the use of calcium supplements, vitamin D and its active metabolites, hormone replacement therapy, and the newer bisphosphonates, alendronate and risedronate.
- Strategies for both prevention of bone loss and fractures in patients initiating glucocorticoid therapy
- Treatment of patients with established glucocorticoid-induced osteoporosis
Here are the ACR s recommendations for the prevention and treatment of glucocorticoid-induced osteoporosis:
For patients beginning therapy with glucocorticoids (equivalent to 5 mg/day of prednisone) for treatment expecting to last three 3 months, the ACR recommends:
- Modify lifestyle risk factors for osteoporosis
– Smoking cessation or avoidance
– Reduction of alcohol consumption if excessive
- Instruct in weight-bearing physical exercise
- Initiate calcium supplementation.
- Initiate supplementation with vitamin D (plain or activated form).
- Prescribe bisphosphonate (premenopausal women should use with caution).
In addition to the above, for patients receiving long-term glucocorticoid therapy the ACR recommends:
- Prescribe treatment to replace gonadal sex hormones if deficient
- Measure bone mineral density (BMD) at lumbar spine and/or hip
- If BMD is not normal (i.e., T-score below -1), then prescribe bisphosphonate (use with caution in premenopausal women)
- Consider calcitonin as second-line drug if patient can not tolerate bisphosphonate therapy
- If BMD is normal, follow up and repeat BMD measurement either annually or biannually.
According to the National Osteoporosis Foundation (NOF), a diet that is rich in calcium and vitamin D and a lifestyle that includes regular weight-bearing exercise are the best ways to prevent weakened bones in later life. Getting enough calcium all through your life helps to build and keep strong bones.
In 1997 the National Academy of Sciences (NAS) suggested that people from age 31 to 50 get 1000 mg (milligrams) of calcium each day. The NOF recommends people over 50 should get 1200 mg daily.
Our bodies use vitamin D to absorb calcium. The NAS recommends people age 51 to 70 need 400 IU (international unit) each day and those over 70 should receive 600 IU. Be careful, more than 2000 IU of vitamin D each day may cause harm to your liver and even lower bone mass.