Conventional treatments for ankylosing spondylitis

Abstract

Management of ankylosing spondylitis (AS) is challenged by the progressive nature of the disease. To date, no intervention is available that alters the underlying mechanism of inflammation in AS. Currently available conventional treatments are palliative at best, and often fail to control symptoms in the long term. Current drug treatment may perhaps induce a spurious state of "disease remission," which is merely a low level of disease activity. Non-steroidal anti-inflammatory drugs are first line treatment, but over time, the disease often becomes refractory to these agents. Disease modifying antirheumatic drugs are second line treatment and may offer some clinical benefit. However, conclusive evidence of the efficacy of these drugs from large placebo controlled trials is lacking. Additionally, these drugs can cause treatment-limiting adverse effects. Intra-articular corticosteroid injection guided by arthrography, computed tomography, or magnetic resonance imaging is an effective means of reducing inflammatory back pain, but controlled studies are lacking. A controlled study has confirmed moderate but significant efficacy of intravenous bisphosphonate (pamidronate) treatment in patients with AS; further evaluation of bisphosphonate treatment is warranted. Physical therapy and exercise are necessary adjuncts to pharmacotherapy; however, the paucity of controlled data makes it difficult to identify the best way to administer these interventions. Surgical intervention may be required to support severe structural damage. Thus, for patients with AS, the future of successful treatment lies in the development of pharmacological agents capable of both altering the disease course through intervention at sites of disease pathogenesis, and controlling symptoms.

Figure 1

Short term symptomatic efficacy of celecoxib and ketoprofen in treating ankylosing spondylitis⁴; p=0.0008 (treatment), *p<0.05 v placebo, †p<0.001 v placebo. Adapted and reprinted, with permission from the authors and Wiley-Liss, Inc, a subsidiary of John Wiley and Sons, Inc, from reference 4. Copyright © 2001 Wiley-Liss.

Figure 2. Short term symptomatic efficacy of ximoprofen in treating ankylosing spondylitis in a dose ranging study.⁵ Adapted and reprinted, with permission from the authors and the Scandinavian Journal of Rheumatology, from reference 5. Copyright © 1994 Taylor and Francis.

Figure 3

Effect of sulfasalazine on pain (measured on a VAS) over time among patients who completed six months of the study, by disease subgroup (ankylosing spondylitis, psoriatic arthritis, and reactive arthritis). Statistical analysis was performed using repeated measures analysis of variance.²⁸ Adapted and reprinted, with permission from the authors and Wiley-Liss, Inc, a subsidiary of John Wiley and Sons, Inc, from reference 28. Copyright © 1995 Wiley-Liss.

Figure 4

A study of the efficacy of CT guided intra-articular triamcinolone 40 mg injections in SpA related sacroiliitis shows that a clear improvement of MRI proven sacroiliitis and inflammatory back pain occurred.⁵⁰ A statistically significant improvement was measured in 25/30 (83%) patients with disease subjectively lasting 8.9 (SD 5.3) months. Sacroiliac inflammation was assessed by diagnostic MRI, and subjective back pain was assessed on a VAS (0=no pain; 10=very severe pain) before and after treatment. Adapted and reprinted, with permission from the authors and the Journal of Rheumatology, from reference 50. Copyright © 1996 Journal of Rheumatology.

Figure 5

Efficacy of prednisolone 62.5 mg versus placebo injections of sacroiliac joints in 10 patients with SpA confirms that corticosteroid injections of inflamed sacroiliac joints are effective.⁵³ n=number of joints. This previously unpublished figure is based on data published by Dr Y Maugars et al in the British Journal of Rheumatology and is printed with the authors' permission.

Figure 6

Effects of pamidronate on clinical outcomes in AS at six months.⁶⁵ Adapted and reprinted, with permission from the authors and Wiley-Liss, Inc, a subsidiary of John Wiley and Sons, Inc, from reference 65. Copyright © 2002 Wiley-Liss.