Minority of Nonradiographic-Axial SpA Patients will Progress to Ankylosing Spondylitis Save

Wang and coworkers from the Rochester Epidemiology Project presented their findings at the annual Spondyloarthritis Research and Treatment Network.(SPARTAN) in Denver, CO. The study compared the outcomes of 16- to 45-year-old Olmstead county residents meeting ASAS imaging criteria for nr-AxSpA (8 of 1,142) and compared this to another 1009 patients with chronic back pain – 65 of whom met clinical criteria for nr-AxSpA (as they were HLA-B27, but had no MRI).

With a mean follow-up of 10.7 years, the overall rate of progression from nr-AxSpA to ankylosing spondylitis was 6.4% at 5 years, 17.3% at 10 years, and 26.4% at 15 years. Interestingly, patients meeting the imaging criteria for nr-AxSpA were 3.5-fold more likely to progress to ankylosing spondylitis compared with those who only met the clinical criteria for nr-AxSpA.