Research has tied rheumatoid arthritis -- the autoimmune disease that can cause debilitating swelling of the joints -- with increased risk of osteoporosis and accelerated bone loss. Indeed, people over 50 with the condition are more likely to break a bone from falling or even from coughing.
But less is known about what impact rheumatoid arthritis has on the bones of younger sufferers -- many of whom begin seeing symptoms at age 25.
In a new study looking at more than 2,300 adults, researchers with the Mayo Clinic found that women under 50 with rheumatoid arthritis are also at greater risk of breaking bones than those without the diesase. Men also saw greater risk of fractures, but the risk did not increase until they were older.
"Young women do have an increase risk for fractures, and that fracture risk occurs before 50," explained lead researcher Dr. Shreyasee Amin, a rheumatologist with the Mayo Clinic.
"When people break a bone from low trauma, it's a sign that the bones are weaker," she continued. "As we get older, our bones thin, so these women may be at particularly high risk [for problems] as they age."
Bone health is a major issue in the U.S.
A 2004 report from the Surgeon General estimated that 1.5 million osteoporotic fractures occur each year, leading to more than half a million hospitalizations and between $12 and $18 billion in direct care costs. A recent study found that one year after a hip fracture, the risk of death doubles in women aged 70 to 79 and quintuples in women aged 65 to 69.
The Centers for Disease Control estimates that 1.5 million people in the U.S. have rheumatoid arthritis, and that more women than men have the disease, which means many women may at be risk for such issues.
"What's important about [the Mayo] study is it's showing that not only are these women's bones thin, but they're having fractures," said Dr. Joan Van Feldt, a professor of medicine in the University of Pennsylvania's rheumatology division. "When you think about women in their 40's -- 40's! -- having fractures, it makes us question what other influences are going on. Do they have issues with muscle mass, too?"
The authors of the new study, which is being presented Monday at the American College of Rheumatology's annual meeting, are not entirely certain what exactly underlies the link.
Amin explained that rheumatoid arthritis may directly cause the problem. Certain proteins that drive inflammation in the joints of rheumatoid arthritis sufferers also seem to have an effect on bone cells, causing increased loss of the cells.
But there are other possible factors. People with rheumatoid arthritis may be less active as a result of their pain, which means they do not exercise or stay active -- a key in maintaining bone mass. The glucocorticoid medications prescribed to treat rheumatoid arthritis can also increase bone loss.
As researchers continue to tackle these questions, they say the current study highlights the pressing need for even very young women with rheumatoid arthritis to take care of their bones.
"The take-home message is to minimize any other risk factors that could be contributing to osteoporosis and accelerated bone loss," Amin said. "If you are a smoker, quitting is one thing you can do. Make sure you're getting adequate vitamin D and calcium."