Information on this page applies to patients with AS or nr‑axSpA.
to help you strive for disease control
ASDAS LDA
About the Ankylosing Spondylitis Disease Activity Score (ASDAS):
ASDAS is an ASAS-EULAR guideline-recommended composite index that assesses disease activity in AS and nr‑axSpA.1
In AS patients with low BASDAI scores that continue to complain of pain or have high inflammatory scores, the use of ASDAS in addition to BASDAI may be an option.2
ASDAS has majority consensus from ASAS and OMERACT, and has emerged as an appropriate instrument for the assessment of disease activity as recommended by ASAS-EULAR.1,3
ASDAS considers both patient-reported findings and objective lab results:4
Back pain
(BASDAI question 2)
Peripheral joint pain/swelling
(BASDAI question 3)
Duration of morning stiffness
(BASDAI question 6)
Patient Global Assessment of disease activity
Inflammation (CRP)
ASDAS scoring and disease activity states:
ASDAS-CRP score can be calculated as follows:4
0.121 × total back pain
0.110 x patient global
0.073 × peripheral pain/swelling
0.058 × duration of morning stiffness
0.579 × Ln(CRP+1)
Try this online ASDAS Calculator
ASDAS disease activity states are defined using the following cutoffs: a score below 1.3 is considered inactive disease, between 1.3 and 2.1 is considered low disease activity, between 2.1 and 3.5 is considered high disease activity, and above 3.5 is considered very high disease activity.5
ASDAS Disease Activity States5
According to ASDAS improvement criteria for AS, a change in the score of at least 1.1 units is equivalent to a “clinically important improvement,” and a change of at least 2.0 units is called a “major improvement.”4
ASAS40
About the Assessment of SpondyloArthritis international Society 40% improvement (ASAS40):
ASAS40 is defined as at least 40% improvement and an absolute improvement of at least 2 units on a numeric rating scale (0-10) from baseline in at least 3 of the following 4 domains, with no worsening in the fourth domain:6
- Patient Global Assessment of disease activity
- Total back pain defined on a numeric rating scale (0–10) based on the following question: “What is the amount of back pain that you experienced at any time during the last week?”
- Physical function (assessed by BASFI)
- Inflammation (Morning Stiffness) (mean of BASDAI questions 5 and 6 on severity and duration of morning stiffness)
Patient resources
FaceYourBackPain.com is AbbVie’s website for patients with AS or nr‑axSpA. Encourage your patients to visit the site to learn more about their condition, understand treatment options and lifestyle modifications, or find a support group.
Visit FaceYourBackPain.com.
AS=ankylosing spondylitis; ASAS=Assessment of SpondyloArthritis international Society; ASDAS=Ankylosing Spondylitis Disease Activity Score; BASDAI=Bath Ankylosing Spondylitis Disease Activity Index; CRP=C-reactive protein; EULAR=European Alliance of Associations for Rheumatology; LDA=low disease activity; nr‑axSpA=non-radiographic axial spondyloarthritis; OMERACT=Outcome Measures in Rheumatology; RA=rheumatoid arthritis.
References: 1. Ramiro S, Nikiphorou E, Sepriano A, et al. ASAS-EULAR recommendations for the management of axial spondyloarthritis: 2022 update. Ann Rheum Dis. 2023;82(1):19-34. doi:10.1136/ard-2022-223296 2. Jun JB, Koo BS, Lee S, Kim J, Kang J, Kim TH. ASDAS is more important than BASDAI in advanced ankylosing spondylitis [abstract]. Arthritis Rheumatol. 2019;71(suppl 10). Accessed March 14, 2023. https://acrabstracts.org/abstract/asdas-is-more-important-than-basdai-in-advanced-ankylosing-spondylitis/ 3. Machado PM, Landewé RB, van der Heijde DM. Endorsement of definitions of disease activity states and improvement scores for the Ankylosing Spondylitis Disease Activity Score: results from OMERACT 10. J Rheumatol. 2011;38(7):1502-1506. doi:10.3899/jrheum.110279 4. Landewé R, van Tubergen A. Clinical tools to assess and monitor spondyloarthritis. Curr Rheumatol Rep. 2015;17(7):47. doi:10.1007/s11926-015-0522-3 5. Machado PM, Raychaudhuri SP. Disease activity measurements and monitoring in psoriatic arthritis and axial spondyloarthritis. Best Pract Res Clin Rheumatol. 2014;28(5):711-728. doi:10.1016/j.berh.2014.10.004 6. Sieper J, Rudwaleit M, Baraliakos X, et al. The Assessment of SpondyloArthritis international Society (ASAS) handbook: a guide to assess spondyloarthritis. Ann Rheum Dis. 2009;68(suppl 2):ii1-ii44. doi:10.1136/ard.2008.104018
