Systematic Review Of Sulfasalazine For Ankylosing Spondylitis

Background. Ankylosing spondylitis(AS) is a chronic inflammatory disease of unknown cause and affects mainly the spine but can also affect other joints. Disease progression may result in loss of mobility and function. Sulfasalazine(SSZ) is a disease-modifying anti-rheumatic drug used in the treatment of AS. However, its efficacy remains unclear. This is an update of a Cochrane review first published in 2005.Objective. To evaluate the benefits and harms of sulfasalazine for the treatment of ankylosing spondylitis.Methods. Relevant randomized and quasi-randomized trials in any language were sought using the following sources: CENTRAL(Cochrane Central Register of Controlled Trials, Issue 11 of 12, 2013), MEDLINE(2003 to 28 November 2013), EMBASE(2003 to 27 November 2013), CINAHL(2003 to 28 November 2013), Ovid MEDLINE data, World Health Organization International Clinical Trials Registry Platform(28 November 2013) and the reference sections of retrieved articles. The Cochrane Collaboration’s Review Manager 5.2 software was used for data analysis.Results. No new study was added in the current version after the updated search. In the original review, eleven studies met the inclusion criteria and were included in the data analysis, involving 895 participants in total. All included studies compared SSZ with placebo. Most of the studies were judged as low risk of bias or unclear risk of bias in five domains(random sequence generation, allocation concealment, blinding of outcome assessment, selective reporting and other sources of bias). However, for incomplete outcome data, only one trial was judged as low risk of bias.None of the included trials assessed BASDAI, BASFI, BASMI and radiographic progression. Different parameters were used to assess pain. The pooled MD for back pain measured on a 0 to 100 VAS scale was-2.96(95% confidence interval(CI)-6.33 to 0.41; absolute risk difference 3%, 95% CI 1% to 6%; 6 trials). Compared to placebo, significantly higher rate of withdrawals due to adverse effects(RR 1.50, 95% CI 1.04 to 2.15; absolute risk difference 4%, 95% CI 0.4% to 8.8%; 11 trials) was found in the SSZ group. A serious adverse reaction was reported in one patient taking SSZ(Peto odds ratio 7.50, 95% CI 0.15 to 378.16).Conclusions. There is not enough evidence to support any benefit of SSZ in reducing pain, disease activity, radiographic progression or improving physical function and spinal mobility in the treatment of AS.