Assessment of your AS
There are a number of ways in which AS is assessed when a diagnosis is being made. You may have physical examinations by your nurse, physiotherapist or doctor to assess your flexibility and joint tenderness. Blood tests may also be used to assess your AS, e.g. erythrocyte sedimentation rate (ESR), a blood test that measures the level of inflammation in your body. There is also a genetic test which can identify if you have the HBL-B27 gene – about 90-95% of people with AS in Europe have this gene.
Ongoing assessments may also be carried out to see if there are any changes in your condition. One or more of the following assessments are normally used.
Bath Ankylosing Spondylitis Disease Activity Index (BASDAI)
BASDAI measures the extent of five main symptoms:
- Fatigue (severe tiredness)
- Spinal pain
- Joint pain/swelling
- Areas of localised tenderness
- Morning joint stiffness
The score, calculated by a healthcare professional, is based on answers to six questions. It will record a score between 1 and 10. A higher score indicates more disease activity.
Bath Ankylosing Spondylitis Functional Index (BASFI)
BASFI measures the impact of AS on your ability to carry out everyday tasks. The score (between 1 and 10), calculated by a healthcare professional, is based on answers to ten questions. A higher score indicates a greater impact on your ability to carry out everyday tasks.
Bath Ankylosing Spondylitis Patient Global score (BAS-G)
BAS-G assesses the effect of AS on your wellbeing over the previous week and the last six months. Based on answers to two questions, a healthcare professional will calculate the score (between 1 and 10). A higher score indicates a greater impact on your wellbeing.
Bath Ankylosing Spondylitis Metrology Index (BASMI)
BASMI measures the impact of AS on the spine’s mobility and on your physical ability. A healthcare professional will assess the spine’s flexibility and take five clinical measures. The higher the score, the more limited movements are. It is expected that the BASMI score may get higher over time as the disease progresses.