Ankylosing Spondylitis Disease Activity Score with ESR (ASDAS-ESR)
ASDAS-ESR Calculator
mm/hr
Score:–
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Stratifies severity of ankylosing spondylitis (AS) using clinical and laboratory data, specifically ESR.
Why Use
The ASDAS-CRP is the preferred disease activity index according to the Assessment of SpondyloArthritis international Society (ASAS), but the ASDAS-ESR may be used as an alternate. May be useful for trending disease activity over time.
Formula
ASDAS-ESR = (0.08 x back pain) + (0.07 x duration of morning stiffness) + (0.11 x patient global assessment of disease activity) + (0.09 x Peripheral pain/swelling) + (0.29 x √(ESR)) Where variables are: Back pain Ask the patient: "How would you describe the overall level of AS neck, back, or hip pain you have had?" Morning stiffness Ask the patient: "How would you describe the overall level of morning stiffness you have had from the time you wake up?" Patient global assessment of disease activity Ask the patient: "How active was your spondylitis, on average, during the last week?" Peripheral pain/swelling Ask the patient: "How would you describe the overall level of pain/swelling in joints other than neck, back, or hips you have had?" ESR Erythrocyte sedimentation rate, mm/h All variables, except ESR, should be graded on a scale of 0 (least severe) to 10 (most severe).
Pearls / Pitfalls
Other than ESR, all values are self-reported by the patient and therefore subjective.
Advice
May be useful in helping to guide treatment decisions; e.g. detecting improvement with TNF inhibitors.
More Information
Interpretation: ASDAS-ESR Disease activity <1.3 Inactive 1.3-2.0 Low 2.1-3.5 High >3.5 Very high