New guidelines for the treatment of non-radiographic axial spondyloarthritis call for treatment with tumor necrosis factor (TNF) blockers if non-steroidal anti-inflammatory drugs (NSAIDs) fail.
But very little is known about this relatively new category of rheumatic disease, and almost all questions about diagnosis and treatment are in need of more research, said Michael Ward, MD, MPH, a researcher for the National Institutes of Health and the principle investigator of the project that was designed to determine best practices for treating non-radiographic axial spondyloarthritis (SpA) and ankylosing spondylitis (AS).
The guidelines were developed by a committee of rheumatology experts under the auspices of the American College of Rheumatology (ACR). Because there has been little work on non-radiographic axial spondyloarthritis outside of trials of TNF inhibitors, the researchers had to fall back on data from ankylosing spondylitis research when making recommendations for non-radiographic axial spondyloarthritis.
"Non-radiographic axial SpA is a relatively new classification of patients with symptoms similar to AS but no x-ray findings indicative of AS," Ward said in an interview with Rheumatology Network. It's not clear if the two conditions are related, but distinct, Ward said, or if the non-radiographic diagnosis is a precursor phase. However, non-radiographic axial spondyloarthritis patients are an important subgroup, studies have found. One 2013 review published in the journal Arthritis and Rheumatology put the number of non-radiographic axial spondyloarthritis cases at between 20 percent and 80 percent of all axial spondyloarthritis diagnoses.
The researchers issued recommendations for 20 clinical questions about non-radiographic axial spondyloarthritis that overlapped with questions about the latter disorder. All of the research focused on treatment in adults.
The recommendation with the strongest direct evidence called for treatment with TNF inhibitors in patients for whom NSAIDs aren't effective against active non-radiographic axial spondyloarthritis. Based on five controlled trials of adalimumab certolizumab, etanercept and infliximab, the guideline committee conditionally recommended TNF inhibitor treatment over no TNF inhibitor treatment for these patients. In each study, TNF inhibitors proved more effective than placebo, but the size of the effect varied. Thus, the conditional recommendation indicates that patients should be educated on the pros and cons of the treatment and take an active role in the final treatment decision. In contrast, TNF inhibitor treatment was strongly recommended for patients with ankylosing spondylitis, indicating firmer evidence for benefit in that condition.
For the remainder of the overlapping treatment concerns between the two disorders, non-radiographic axial spondyloarthritis recommendations were identical to recommendations for ankylosing spondylitis. The new guidelines include a strong recommendation to treat the disorder with NSAIDs over no NSAID treatment, but the researchers found no evidence to recommend any particular NSAID as a preferred choice. Physical therapy is strongly recommended over no physical therapy, and the use of validated ankylosing spondylitis disease activity measure is conditionally recommended over no regular use of such a measure to monitor disease progress in non-radiographic axial spondyloarthritis.
Recommendations for the treatment of non-radiographic axial spondyloarthritis (SpA):
Prior to these guidelines, as preliminary as they may be, there had been no treatment recommendations for non-radiographic axial spondyloarthritis in the United States, Ward said. The ACR specified a method of evaluating the current research called Grading of Recommendations Assessment, Development and Evaluation (GRADE), a process that involved defining the most important clinical questions, reviewing the literature and evaluating the strengths and weaknesses of the studies in question.
The new recommendations were published online simultaneously in the journals Arthritis Care and Research and Arthritis and Rheumatology on September 24.
Ward, M. M., Deodhar, A., Akl, E. A., Lui, A., Ermann, J., Gensler, L. S., Smith, J. A., Borenstein, D., Hiratzka, J., Weiss, P. F., Inman, R. D., Majithia, V., Haroon, N., Maksymowych, W. P., Joyce, J., Clark, B. M., Colbert, R. A., Figgie, M. P., Hallegua, D. S., Prete, P. E., Rosenbaum, J. T., Stebulis, J. A., van den Bosch, F., Yu, D. T. Y., Miller, A. S., Reveille, J. D. and Caplan, L. (2015), American College of Rheumatology/Spondylitis Association of America/Spondyloarthritis Research and Treatment Network 2015 Recommendations for the Treatment of Ankylosing Spondylitis and Nonradiographic Axial Spondyloarthritis. Arthritis Care Res. doi: 10.1002/acr.22708
Sieper, J. and van der Heijde, D. (2013), Review: Nonradiographic axial spondyloarthritis: New definition of an old disease? Arthritis & Rheumatism, 65: 543–551. doi: 10.1002/art.37803