If you have rheumatoid arthritis, your rheumatologist probably told you that you’re at risk of developing weakened, brittle bones that can fracture easily. If you’re also taking an oral corticosteroid, that risk increases.

RA is a chronic autoimmune disorder in which the body’s immune system goes into overdrive, mistakenly attacking its own healthy tissues. It is characterized by the production of proteins called cytokines that cause widespread inflammation throughout the body. The hallmark symptom of RA is painful joint damage and destruction, but RA affects multiple organ systems, including the heart, lungs, blood vessels, eyes and skin. RA also attacks the bones, and can cause loss of bone mass.

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Three main types of medications are prescribed to control RA’s inflammation and limit damage to the joints and organs. They include disease-modifying antirheumatic drugs like methotrexate, biologics like etanercept and oral corticosteroids like prednisone. DMARDS and biologics target the different inflammatory proteins and processes associated with RA and suppress the disease’s overactive immune response.

Corticosteroids are powerful anti-inflammatory medications that begin immediately to subdue symptoms of inflammation due to any cause, but they do not alter the mechanism of action of the underlying disease. They are typically prescribed in conjunction with methotrexate or a biologic when RA is first diagnosed.

“Prednisone is typically given as a bridge therapy until other RA medications take effect, which can take weeks to months, depending on the medication,” says Dr. Jonathan Greer, a rheumatologist in Palm Beach, Florida. “You start with a larger [dose] of prednisone to reduce inflammation as quickly as possible, and then gradually taper down,” he adds. “The recommendation is to prescribe prednisone for eight to 12 weeks to see how effective the other medications are. Some medications work faster than others,” he explains. The goal is to eventually discontinue steroid use, if possible.

Both RA and corticosteroids interfere with the normal life cycle of bone.

Bones are living tissue made up of individual cells that, like the body’s other cells, are constantly dying and being renewed. Until about the age of 30, we make more bone than we lose. After that, the process is reversed, and the body slowly loses more bone than it makes. With time, so much bone can be lost that it can lead to osteopenia — weakened bones, which afflicts approximately 50 percent of all adults over 50 — or even osteoporosis, in which the bones have lost so much bone mineral density that they become porous and brittle.

“Oral corticosteroids can cause bone loss immediately,” Greer says. “This effect is greatest in the first six months of use and plateaus after that,” says Greer, an affiliate clinical professor of medicine at Nova Southeastern University of Osteopathic Medicine in Fort Lauderdale.

It can still take years before osteopenia or osteoporosis set in, or it can occur much faster. The effect is generally dose-dependent.

“It is well-known that corticosteroids at high doses increase the risk of fracture,” says Dr. Joshua Baker, an assistant professor of rheumatology and epidemiology at the Perelman School of Medicine of the University of Pennsylvania in Philadelphia. “It is less clear what the impact is of the low doses that are typically used in early RA,” he adds.

“Compared to RA patients who do not take corticosteroids, there is likely to be a modest increase in risk with low doses of corticosteroids, or 5-10 milligrams per day,” Baker says. “Prolonged exposure to high doses is where the greatest risk is seen.”

“Prednisone is a double-edged sword,” Greer says. “I tell my patients that the ‘p’ in prednisone stands for poison, because it can lead to diabetes, cataracts, bruising and bleeding, infections, moon face and weight gain. These effects always occur if you stay on prednisone long term, [versus] methotrexate, where side effects might or might not occur,” he adds.

Rheumatologists typically prescribe the lowest dose possible to suppress inflammation and pain while limiting bone loss and the other potentially serious side effects of steroids. However, although this strategy slows bone loss, it likely does not completely stop it from occurring.

“A lower dose decreases the risk of significant bone loss, but it probably doesn’t completely mitigate it,” Baker says. “Bone loss has been observed even among individuals taking relatively low doses. However, it is likely to be modest and may only be clinically relevant with long-term use,” he notes.

Moreover, “some patients need long-term, higher dose corticosteroid therapy to decrease inflammation, between 15-20 mg per day,” Greer says.

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Baker also points out that steroids may not be the whole story in individuals with RA.

“One issue with quantifying these effects is that, in epidemiologic studies, the people that take steroids usually tend to have worse RA,” he explains. “Severe RA is also associated with a greater risk of fracture.”

Some individuals with RA have a higher risk of osteoporosis than others, Baker adds. “Older patients who are thin, have longer disease duration, greater joint damage and higher RA disease activity are likely to have the highest risk of fracture,” he says.

According to Baker, stopping corticosteroids can help slow the rate of bone loss, but it does not reverse the damage that has already been done.

“The risks related to long-term use of corticosteroids do not go away once the drug is discontinued,” he notes.

“It’s a controversial issue,” Greer says. “When people with RA don’t move, their bones melt away,” he says. “If you use steroids, you increase the rate of bone loss, but you also decrease inflammation, which causes the patient to move more and engage in more weight-bearing activities, which in itself slows bone loss. Movement and weight-bearing activities induce bone growth.”

So if you have RA and must take corticosteroids to help control inflammation and pain, what can you do to help protect your skeleton?

“We frequently recommend bone density scans for patients who are or have been on long-term corticosteroids,” Baker says. “Whether [a bone scan is done] and how frequently bone density is monitored may depend on the patient’s age, dose of prednisone, severity of illness and other medical illnesses.”

Calcium and vitamin supplements can also help mitigate the effect of steroids on the skeleton.

“Rheumatologists typically recommend calcium and vitamin D supplements in patients [with RA] taking long-term corticosteroids,” Baker says.

Greer advises that his patients take between 600 and 1000 mg of calcium citrate each day, divided into a morning and evening dose. “Most calcium supplements on the market are in the form of calcium carbonate, but calcium citrate is more readily absorbed by the body,” Greer says. “It also does not need to be taken with food,” he notes.

Along with calcium, Greer tells his patients to take between 1000 and 2000 mg of vitamin D-3 each day. “The dose depends on the patient’s age and gender,” he says. “Women, particularly postmenopausal women, need a higher dose.”

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Other interventions may also be necessary.

“[RA patients] taking [higher] doses of steroids, or those who have a greater risk of bone loss and fracture for other reasons, may benefit from using medications that prevent bone loss and fracture, such as bisphosphonate therapies,” Baker says. These include Fosamax, Boniva and Actonel.

Although corticosteroids are powerful medications with potentially serious side effects, you should not be afraid to take them if your doctor prescribes them.

“Low dose steroids are one of the most effective ways to reduce inflammation and help you feel better,” Baker says. “If you and your rheumatologist think you need them to reduce inflammation, there is no reason to avoid them,” he adds. “The relatively small loss of bone that may occur with these low doses is probably outweighed by the benefit in these cases. However, most rheumatologists would recommend trying to eventually find a treatment strategy that works well enough that you don’t need to take corticosteroids over the very long term,” he concludes.

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Oral Steroids Increase the Risk of Osteoporosis in People With Rheumatoid Arthritis originally appeared on usnews.com