Women who have ankylosing spondylitis and men and women who have had the disease longer have an increased risk of developing potentially debilitating symptoms beyond the joints, according to a new study presented at the American College of Rheumatology’s Annual Meeting.
Ankylosing spondylitis (AS) is a chronic inflammatory type of arthritis that predominantly affects the spine and the sacroiliac joints, the two joints that connect the base of the spine with the right and left sides of the pelvis. It is the most common subtype of a group of disorders called axial spondyloarthropathies (axSpA). AxSpA is associated with several symptoms – caused by the same out-of-control, body-wide inflammation that sets off the arthritis – that are not in the joints (called extra-articular manifestations). These include:
- uveitis (inflammation in a certain part of the eye)
- psoriasis (chronic, severe skin rashes)
- inflammatory bowel disease (Crohn’s disease, ulcerative colitis)
But until now, it was not known how many AS patients develop these three conditions, who is at greatest risk or which symptoms are most common in which subgroup of patients.
To get a better idea, researchers analyzed data on 564 patients (almost 80 percent male) in the Ankylosing Spondylitis Registry of Ireland. They found the following:
- Just over 50 percent of study participants had at least one of the three conditions
- 35.5 percent of patients had uveitis, the most common of the three
- The prevalence of uveitis was significantly higher in women than men (46.7 percent versus 32.3 percent) and in men and women who had had the disease for 10 years or longer than in those who had had it less than 10 years (39.8 percent versus 21.7 percent)
- 17.8 percent had psoriasis
- 9.7 percent had inflammatory bowel disease (IBD)
- The prevalence of IBD was significantly higher in women than in men (16.5 percent versus 7.7 percent)
Study co-author Gillian Fitzgerald, MD, a rheumatology fellow at St. James’s Hospital in Dublin, Ireland, says that these conditions add to the burden of disease, or “morbidity.”
“Each of these extra-articular manifestations alone has morbidity, and our patients can often have several of these conditions in addition to the morbidity from inflammatory back pain,” she says. “This can have a huge impact on their quality of life, so it is important for us as rheumatologists to understand as much as we can about them.”
Dr. Fitzgerald says it’s not known why women are at higher risk for these conditions, but adds that it’s important to be aware that they are, especially because AS was long thought to be a disease that affected mostly men – although recent research indicates that isn’t the case.
“The key message is, not only do we now have to think of women having the disease, but in the women who have it, we also have to think that they are more likely to get some of these extra-articular manifestations. So every time we see female patients, we need to think about this, ask about these symptoms, screen when necessary and make sure we are not missing it,” Dr. Fitzgerald explains.
“I think a lot of patients think it’s only back pain they should mention, but we are interested in all symptoms. So if they have problems with their skin or eyes or with inflammatory bowel disease, we want them to know to talk with their rheumatologist about it,” she says.
Theodore Fields, MD, a rheumatologist at Hospital for Special Surgery in New York City, says the Ankylosing Spondylitis Registry of Ireland, which has been collecting data since 2013, is a valuable resource.
“Over time, as the years of prospective data accumulation grow, data from this registry can assist in anticipating complications of axial spondyloarthropathy in different patient groups,” Dr. Fields says.
Even now the study has value for clinical practice, he notes, leading doctors to increase surveillance for uveitis in women and those with long-standing disease and to look carefully for subtle inflammatory bowel disease.
“For the moment, all patients with axial spondyloarthropathy need to be under observation for the spectrum of associated conditions, but further fine-tuning of subsets of patients at special risk of particular manifestations will help us better focus our screening,” Dr. Fields says.
Dr. Fitzgerald agrees that more research is needed on this topic. She plans further study to identify other characteristics that can predict the development of these conditions.
Author: Jennifer Davis for the Arthritis Foundation