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Ankylosing spondylitis

Ankylosing spondylitis (AS) is an inflammatory condition that affects the joints in your spine. In AS, the spinal joints, ligaments and the sacroiliac joints (the joints at the base of the spine) become inflamed leading to pain and stiffness in the neck and back.

It can sometimes affect your other joints and different parts of your body – including your tendons and eyes. Symptoms vary from person to person – from so mild that you can almost forget you have the condition, to more serious which have a big impact on your quality of life.

Ankylosing spondylitis is three times more common in men than women1 and tends to start at a young age. It can be difficult to diagnose because the first symptom is often recurring back pain and stiffness that slowly gets worse, and which can be ignored by the patient or their doctors. There may be x-ray signs of the condition in people who have no symptoms for several years. The joint with the most frequent x-ray changes is the sacroiliac joint, the joints on both sides of the base of the spin where it links with the pelvis.

There are few data on the number of cases and the impact of ankylosing spondylitis from the UK. The most recent data we have are from Sweden, but it’s very likely that the rates in the UK will be very similar.

How common is ankylosing spondylitis in the UK?

Estimated prevalence data (study originally from southern Sweden) and applied to the UK population2,3:

Age group Prevalence (%) UK estimate 
0.03 3,764
30–44 0.16
45–59 0.23
60–74 0.25
Total 0.16

What is the healthcare impact of ankylosing spondylitis in the UK?

In 2012-13, there were 3,766 hospital consultant episodes for AS4 (cases where people saw a specialist doctor for their condition in a hospital setting), 76% of these were male.

Also in 2012-13, there were 2,844 outpatient appointments for AS5 (this is where a patient meets with a medically trained doctor/nurse who specialises in the care they require, but in an outpatient area, rather than a hospital).


1.  Dean LE, et al. (2013) Global prevalence of ankylosing spondylitis. Rheumatology (Oxford). 2013 Dec 9. Epub ahead of print doi:10.1093/rheumatology/ket387

2.  E Haglund et al. (2011). Prevalence of spondyloarthritis and its subtypes in southern Sweden. Ann Rheum Dis 70, 943-948

3.  ONS

4.  Consultant episodes from HES (12/13) Code M45

5.  Outpatient appointments from HES Code M45

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