PT - JOURNAL ARTICLE AU - M Rudwaleit AU - J Listing AU - J Brandt AU - J Braun AU - J Sieper TI - Prediction of a major clinical response (BASDAI 50) to tumour necrosis factor α blockers in ankylosing spondylitis AID - 10.1136/ard.2003.016386 DP - 2004 Jun 01 TA - Annals of the Rheumatic Diseases PG - 665--670 VI - 63 IP - 6 4099 - http://ard.bmj.com/content/63/6/665.short 4100 - http://ard.bmj.com/content/63/6/665.full SO - Ann Rheum Dis2004 Jun 01; 63 AB - Background: TNFα blockers have been shown to be highly efficacious in patients with active ankylosing spondylitis (AS). Objective: To identify parameters predicting the clinical response to TNF blockers in AS. Methods: Patients with active AS participated in two placebo controlled, randomised trials conducted in Germany with infliximab (n = 69) and etanercept (n = 30), respectively. For inclusion in either trial patients had to have high disease activity (BASDAI ⩾4) and a spinal pain score (numerical rating scale 0–10) ⩾4 despite treatment with NSAIDs. A major clinical response was defined as a 50% improvement of the initial BASDAI (BASDAI 50) after 12 weeks’ treatment with active drug. Logistic regression likelihood ratio tests (univariate and multivariate), Student’s t test, and χ2 tests were performed. Results: Univariate analysis showed the following to be predictors of a major response (BASDAI 50) to treatment: shorter disease duration (p = 0.003); lower BASFI (p = 0.007); younger age (p = 0.009); raised ESR (p = 0.033); raised CRP (p = 0.035). After adjustment for disease duration, BASFI, ESR, and CRP, but not age, remained significantly associated. After adjustment for disease duration and for BASFI, ESR, CRP, and in addition, a higher BASDAI were significantly associated with response. The best multivariate model built by stepwise regression contained the covariables disease duration, BASFI, BASDAI, and CRP. Conclusion: A shorter disease duration, younger age, and a lower BASFI are predictors of a major clinical response to TNF blockers in active AS. Raised CRP and a higher BASDAI may also be valuable predictors. These data need to be confirmed in further studies.