Factors associated with ASDAS remission in a long-term study of ankylosing spondylitis patients under tumor necrosis factor inhibitors.

OBJECTIVE

To determine the clinical and demographic factors associated with disease remission and drug survival in patients with ankylosing spondylitis (AS) on TNF inhibitors.

METHODS

Data from a longitudinal electronic database of AS patients under anti-TNF therapy between June/2004 and August/2013. Demographic, clinical parameters, disease activity by ASDAS remission (< 1.3) and inactive/low (< 2.1) were analyzed to characterize reasons for drug survival and switching of anti-TNF.

RESULTS

Among 117 AS patients, 69 (59%) were prescribed only one anti-TNF, 48 (41%) switched to a second anti-TNF and 13 (11%) to a third anti-TNF. Considering ASDAS-CRP < 1.3, 31 (39%) patients were inactive at the end of the study. Non-switchers (P = 0.04), younger age (P = 0.004), non-smoking (P = 0.016), shorter disease duration (P = 0.047), more frequent use of SSZ (P = 0.037) and lower BASDAI (P = 0.027), BASMI (P = 0.034) and BASFI (P = 0.003) at baseline were associated with remission. In the multivariate analysis younger age (P = 0.016) and lower BASDAI (P = 0.032) remained as remission predictors.

CONCLUSION

This study supports that ASDAS-CRP remission is an achievable goal not only for non-switchers but also for second anti-TNF, particularly in patients with younger age and lower BASDAI at baseline. Co-medication and non-smoker status seems to have a beneficial effect in anti-TNF response in this population.