Performance of the Ankylosing Spondylitis Disease Activity Score (ASDAS)

Sofia Ramiro and colleagues presented a study on the performance of the Ankylosing Spondylitis Disease Activity Score (ASDAS) in patients under biological therapies in daily practice. The ASDAS showed a good correlation with the patient’s global assessment (0.66), and simultaneously a good correlation with acute phase reactants (CPR 0.61; ESR 0.52); n.b. the correlation with CRP is better than with ESR, so the CRP based ASDAS is preferred. The authors concluded: “The ASDAS is a discriminatory instrument for disease activity in the setting of usual clinical practice.”
As I’ve already told, I use the ASDAS in clinical practice and I’m very satisfied with this tool.


[SUN] 507
Performance of the Ankylosing Spondylitis Disease Activity Score (ASDAS) in Patients Under Biological Therapies in Daily Practice—Results From the Portuguese Register Reuma.Pt.
Sofia Ramiro1, Pedro Machado2, Raquel Roque3, Helena Santos4, Joaquim Polido-Pereira5, Daniela Peixoto6, Cátia Duarte7, Fernando Pimentel-Santos8, Caˆndida Silva4, J. E. Fonseca5, Filipa Teixeira6, Andrea Marques7, Filipe Araújo8, Jaime C. Branco8, José Pereira Da-Silva7, José Costa6, Jose A. Pereira Da Silva9, Luis Cunha Miranda4, J. Canas da Silva3, Helena Canha˜o5, A.M. Van Tubergen10, Desirée van der Heijde11, Robert Landewé12 and MJ Santos3.
1Hospital Garcia de Orta, Almada, Portugal and Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands, 2Hospitais da Universidade de Coimbra, Coimbra, Portugal and Leiden University Medical Center, Leiden, Netherlands, 3Hospital Garcia de Orta, Almada, Portugal, 4Instituto Portugueˆs de Reumatologia, Lisboa, Portugal, 5Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa and Rheumatology Department, Centro Hospitalar de Lisboa Norte, EPE, Hospital de Santa Maria, Lisboa, Portugal, 6Centro Hospitalar do Alto Minho, Hospital de Ponte de Lima, Ponte de Lima, Portugal, 7Hospitais da Universidade de Coimbra, Coimbra, Portugal, 8Centro Hospitalar de Lisboa Ocidental, Hospital Egas Moniz, Lisboa, Portugal, 9Centro Hospitalar de Lisboa Norte, Hospital de Santa Maria, Lisboa, Portugal, 10Maastricht University Medical Center, Maastricht, Netherlands, 11Leiden University Medical Center, Leiden, Netherlands, 12Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands
Conclusion: The ASDAS is a discriminatory instrument for disease activity in the setting of usual clinical practice.

Ankylosing Spondylitis – Assessing Disease Activity

How to assess disease activity in ankylosing spondylitis? Some people still believe that CRP or ESR are good tools for measuring disease activity in ankylosing spondylitis.
The BASDAI (Bath Ankylosing Spondylitis Disease Activity Index) is a standard tool for measuring and evaluating disease activity in ankylosing spondylitis. The BASDAI is easy to score by patients (fatigue, spinal pain, joint pain/swelling, localized tenderness, morning stiffness duration, morning stiffness severity) and easy to calculate by physicians/health personal. So one should have it at each visit. The patient can even take one home and fill it out, say a week after an infliximab infusion to monitor the therapeutic effect.
The new kid on the block is the ASDAS (Ankylosing Spondylitis Disease Activity Score). The ASDAS is a composite index to assess disease activity in ankylosing spondylitis. The authors of the original text favour the ASDAS-CRP, which takes into calculation: back pain, duration of morning stiffness, patient global, peripheral pain/swelling, and CRP. Most of the data you already have in the BASDAI, you have to ask the patient global ("How active was your spondylitis on average during the last week?") and take blood for CRP. For the ASDAS-ESR you have to take blood for ESR. The formulas to calculate the ASDAS can be easily put into a spreadsheet. Just takes seconds to put in the data and calculate the ASDAS.
How to use the ASDAS? What can you do with the results? If the ASDAS is lower than 1.3 it’s (hooray) inactive disease, 1.3 to lower 2.1 means moderate disease activity, 2.1 to 3.5 means high disease activity, above 3.5 is defined as very high disease activity. A difference of above 1.1 means a clinically important improvement and above 2.0 is defined as a major improvement.
Let’s hope that the ASDAS finds its way into daily practice!

ASDAS-CRP: 0.12 x Back Pain + 0.06 x Duration of Morning Stiffness + 0.11 x Patient Global + 0.07 x Peripheral Pain/Swelling + 0.58 x Ln(CRP+1)
ASDAS-ESR: 0.08 x Back Pain + 0.07 x Duration of Morning Stiffness + 0.11 x Patient Global + 0.09 x Peripheral Pain/Swelling + 0.29 x √(ESR)