The Lupus-Osteoporosis Connection
Over the years, advances in the care and treatment of systemic lupus erythematosus have improved the long-range outlook for people who have this condition. In fact, 80 to 90 percent of lupus patients have a normal life span. However, living longer increases your likelihood of developing osteoporosis, or fragile bones, one of the most common complications of lupus.
Having osteoporosis increases the risk of bone fractures, and even younger people with lupus are vulnerable to fractures, studies indicate. Fortunately, taking certain precautions may lower your risk for osteoporosis and protect your bones.
How lupus raises osteoporosis risk
New cells constantly replace old ones in healthy bones. In osteoporosis, that process is disrupted, causing bones to lose mass and become thin. According to the Centers for Disease Control and Prevention, 16 percent of women over 50 and 4 percent of men past that age have osteoporosis.
However, having lupus appears to increase the risk for fragile bones. Estimates vary, but some research suggests that up to two-thirds of lupus patients will develop osteoporosis, although a variety of factors can affect the strength, or density, of your bones.
Scientists have identified several reasons why lupus patients are more likely to develop fragile bones, starting with the disease itself. Lupus is brought on by uncontrolled inflammation, which can harm blood vessels, limiting the flow of oxygen and nutrients to bone cells.
Lupus patients also tend to have low levels of vitamin D, which is essential for healthy bones. That’s partly because people with lupus often have sensitive skin and avoid sunlight or use sun-blocking products.
While those common-sense steps protect the skin, they also prevent sunlight from triggering vitamin D production in the body. Kidney failure, a complication of lupus, can lower vitamin D levels, too.
Medications used to treat lupus may affect bone health as well. Corticosteroids such as prednisone, which is commonly prescribed for lupus, are a mixed bag when it comes to your bones. On the one hand, prednisone lowers inflammation, which protects your skeleton. Yet corticosteroids also induce bone loss.
The results of studies on prednisone and bone health in lupus are conflicting. However, several recent studies suggest that prednisone only causes harm to bones at doses of 7.5 milligrams daily or higher. Research has not yielded a clear answer as to whether hydroxychloroquine, another medication prescribed for lupus, weakens bones.
Weaker bones mean more fractures
After age 50, half of women and one in six men will experience an osteoporosis-related broken bone. People with lupus have an even greater risk for fractures, although how much more likely they are to break bones is a matter of debate.
The largest study to quantify the fracture risk associated with lupus involved 4,343 patients with the condition, and determined that they were 22 percent more likely than healthy comparison subjects to have broken at least one bone. However, other studies suggest that the risk is significantly higher.
Still other research indicates that up to 42 percent of lupus patients will break a bone at some time after being diagnosed, with fractures most commonly occurring in the hips, spine, ankles, ribs, feet, and arms. While the risk of suffering a fracture increases as a person with lupus ages, studies suggest that up to half of lupus patients ages 32 to 48 have at least one fractured vertebra.
What you can do
You can take action to offset the bone-weakening impact of lupus and its treatments. In addition to maintaining a healthy body weight, not smoking, and avoiding excessive alcohol consumption, take the following measures:
• If you take prednisone, use the lowest effective dose for the shortest period possible.
• Talk to your doctor about calcium and vitamin D supplements. Women over 50 require 1,200 mg of calcium per day, while the requirement is 1,000 mg daily for males, although prednisone users may need higher intake. Milk, yogurt, and other foods are good sources of this mineral, but your diet may not provide enough. Adults require 600 IUs of vitamin D (800 IUs after age 71), although your doctor may recommend a higher intake, which will likely mean taking a supplement.
• Lower your risk for falling by keeping your home well-lighted and free of clutter. Install railings on both sides of staircases and consider adding grab bars in the bathroom.
• Get more exercise. Physical activity such as walking or dancing strengthens bones, yet disability and fatigue can cause lupus patients to avoid exercise. A 2015 study in Arthritis Care & Research involving 146 women with lupus found that many had low muscle strength in their legs, which could make them more prone to falls. Ask your physician what type of exercise program makes sense for you.