Ankylosing Spondylitis Raises Risk for Other Conditions

By Jennifer Davis | Updated April 14, 2022

Women who have ankylosing spondylitis and people who have had the disease for a long period of time have an increased risk of developing symptoms beyond the joints, according to a study by Irish researchers. Another study by the same group found that AS patients who are obese have more severe disease.

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. These include:

• Uveitis (inflammation in a certain part of the eye)
• Psoriasis (chronic, severe skin rashes)
• Inflammatory bowel disease (IBD), such as Crohn’s disease and ulcerative colitis

Until recently, it wasn’t known how many AS patients developed these conditions, which of the conditions were most common and who was at greatest risk of getting them.

To get a better idea, researchers analyzed data on 564 patients (almost 80% male) in the Ankylosing Spondylitis Registry of Ireland. They found that just over 50% of the participants had at least one of the three conditions. Uveitis was the most common, occurring in more than one-third of patients. It was more common in women and in people who had had AS for 10 years or longer. Fewer people had psoriasis and even fewer — around 10% — had IBD, which affected far more women than men.

Study co-author Gillian Fitzgerald, a rheumatologist at Galway University Hospitals in Ireland, says 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.

“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.

In 2020, Dr. Fitzgerald and colleagues published data on a similar group of patients from the Ankylosing Spondylitis Registry of Ireland. Again, a majority of the patients were men, and more than half had more than one co-existing condition. In this group, the most common chronic condition was obesity, which was associated with older age and more severe disease.