Axial Spondyloarthritis is a condition that occurs in young adults¹. It is a possible cause of inflammatory back pain where the inflammatory pain often starts in the lower back and spreads upward over time2.
Ankylosing Spondylitis or AS is a form of Axial Spondyloarthritis in which inflammatory lesions of the sacroiliac joints or spine are present on an X-ray³. AS primarily affects the spine, although other joints can become involved. It causes inflammation of the spinal joints (vertebrae) that can lead to severe, chronic pain and discomfort.⁸

Early intervention can make a difference. Axial Spondyloarthritis is a chronic disease that can worsen over time. Without treatment, the disease can lead to permanent damage7

Who is affected by the disease?

Ankylosing Spondylitis is somewhat more common in men than in women, while non-radiographic Axial Spondyloarthritis is just as common in men as in women4,5. In both cases, the first symptoms usually develop between the ages of 15 and 35. It is uncommon for the condition to start after age 456.

About 5 to 10 in 1000 people have Ankylosing Spondylitis 6

What are the causes of Axial Spondyloarthritis?

Although Axial Spondyloarthritis is a condition that affects the back, the problem comes from the immune system. Axial Spondyloarthritis is thus an “autoimmune disease”. For unknown reasons, the immune system turns against healthy cells of the body, as if they were foreign substances. This can happen in different parts of the body and thus cause inflammation not only in the spine but also in other joints and tissues³. 

Although there is no certainty about the causes, there is a link between the disease and family history. It turns out that people with a specific gene have a higher risk of developing Axial Spondyloarthritis (90% of people with ankylosing spondylitis have the HLA-B27 gene, but most people with this gene will never develop the disease) 6.  

Besides inflammatory back pain, you're more likely to have Axial Spondyloarthritis in the following cases1:

  • You have a positive result for the test for the detection of the gene HLA-B27.
  • You have a family history of axial spondyloarthritis.
  • You have inflammatory bowel disease or psoriasis.
  • You have a recurrent uveitis (= eye infection).


Visit spa-online.be to get more information on the disease of AS, treatment options, supporting groups and the testing on a potential diagnose of AS.


Not the time during your consultations to really get to understand the disease’s profound impact into your patient’s everyday life? Discover our podcast series, with stories from patients suffering from rheumatic diseases (RA, SpA) and comments from rheumatologists Dr Molls and Dr Joos.


  1. Sieper J et al. Ann Rheum Dis 2009;68(Suppl II):ii1-ii44.
  2. National Ankylosing Spondylitis Society (NASS). Differentiating inflammatory and mechanical back pain. 2012.
  3. Rudwaleit et al. Ann Rheum Dis 2009;68:777-83.
  4. van der Heijde et al. Arthritis Rheum 2006;54:2136-2146.
  5. Sieper J et al. Ann Rheum Dis. 2013;72:815-22.
  6. Dean LE et al. Rheumatology (Oxford) 2014;53:650-7.
  7. Machado P et al. Ann Rheum Dis 2010;69:1465-1470.
  8. https://spondylitis.org/about-spondylitis/types-of-spondylitis/ankylosing-spondylitis/ 

AbbVie SA/NV - BE-ABBV-210107 (v1.0) - September 2021