Magnetic Resonance Imaging of the Sacroiliac Joints Indicating Sacroiliitis According to the Assessment of SpondyloArthritis international Society Definition in Healthy Individuals, Runners, and Women With Postpartum Back Pain

Objective: To compare magnetic resonance images (MRIs) of the sacroiliac (SI) joints of healthy subjects and individuals with known mechanical strain acting upon the SI joints to those of patients with axial spondyloarthritis (SpA) and patients with chronic back pain. Methods: Three readers who had received standardized training and were blinded with regard to study group randomly scored MRIs of the SI joints of 172 subjects, including 47 healthy individuals without current or past back pain, 47 axial SpA patients from the Spondyloarthritis Caught Early (SPACE) cohort (with a previous MRI confirmed positive for sacroiliitis), 47 controls with chronic back pain (irrespective of MRI results) from the SPACE cohort, 7 women with postpartum back pain, and 24 frequent runners. MRIs were scored according to the Assessment of SpondyloArthritis international Society (ASAS) definition and Spondyloarthritis Research Consortium of Canada (SPARCC) index. Results: Of the 47 healthy volunteers, 11 (23.4%) had an MRI positive for sacroiliitis, compared to 43 (91.5%) of 47 axial SpA patients and 3 (6.4%) of 47 patients with chronic back pain. Three (12.5%) of the 24 runners and 4 (57.1%) of the 7 women with postpartum back pain had a positive MRI. Using a SPARCC cutoff of ≥2 for positivity, 12 (25.5%) of 47 healthy volunteers, 46 (97.9%) of 47 positive axial SpA patients, 5 (10.6%) of 47 controls with chronic back pain, 4 (16.7%) of 24 runners, and 4 (57.1%) of 7 women with postpartum back pain had positive MRIs. Deep bone marrow edema (BME) lesions were not found in healthy volunteers, patients with chronic back pain, or runners, but were found in 42 (89.4%) of 47 positive axial SpA patients and in 1 (14.3%) of 7 women with postpartum back pain. Conclusion: A substantial proportion of healthy individuals without current or past back pain has an MRI positive for sacroiliitis according to the ASAS definition. Deep (extensive) BME lesions are almost exclusively found in axial SpA patients

In early axial spondyloarthritis, increasing disease activity is associated with worsening of health-related quality of life over time

Objective. In early axial spondyloarthritis (axSpA), data are lacking about the relationship between disease activity and health-related quality of life (HRQOL). We assessed and quantified the association between change in Ankylosing Spondylitis Disease Activity Score (ASDAS) and HRQOL over time in early axSpA. Methods. Baseline and 1-year data of patients with axSpA fulfilling the Assessment of Spondyloarthritis international Society (ASAS) classification criteria from the SPondyloArthritis Caught Early (SPACE) cohort were analyzed. Associations between change in ASDAS and in physical (PCS) or mental component summary (MCS) of the Medical Outcomes Study Short Form-36 were tested by linear regression models. Age, sex, ASAS criteria arm, and blue- versus white-collar work were tested for effect modification. Subsequently, these factors and medication were tested for confounding. Results. There were 161 patients with axSpA [53% male, mean (± SD) age 29.7 (± 7.5) yrs, symptom duration 13.6 (± 7.2) months, HLA-B27-positive 91%, radiographic sacroiliitis 22%] who had ASDAS of 2.5 (± 1.0) and 2.0 (± 0.8), PCS of 28.4 (± 14.3) and 36.9 (± 13.1), and MCS of 48.2 (± 13.8) and 49.3 (± 12.0) at baseline and 1 year, respectively. Per unit increase in ASDAS between baseline and 1 year, PCS worsened by 9.5 points. The same level of disease activity had fewer adverse effects on physical HRQOL in women and white-collar workers. Conclusion. To our knowledge, our data are the first to show that in a broad group of patients with early axSpA, increasing ASDAS is associated with worsening of physical HRQOL, but not mental HRQOL, over time

The Impact of Illness Perceptions and Coping on the Association Between Back Pain and Health Outcomes in Patients Suspected of Having Axial Spondyloarthritis: Data From the SP

Objective: To investigate whether illness perceptions and coping influence the relationship between back pain and health outcomes in patients suspected of having axial spondyloarthritis (SpA). Methods: In the SPondyloArthritis Caught Early cohort, regression models were computed at baseline, with back pain intensity (range 0–10) as the determinant and health-related quality of life, the physical component summary score (PCS) and mental component summary (MCS) of the Short Form 36 (SF-36) health survey, or work productivity loss as outcomes. Subsequently, using Leventhal's Common-Sense Model of Self-Regulation, illness perceptions and, thereafter, coping were added to the models. Analyses were repeated for patients diagnosed and classified as having axial SpA according to the Assessment of SpondyloArthritis international Society axial SpA criteria (ASAS axial SpA), patients only diagnosed with axial SpA (axial SpA–diagnosed only), and those with chronic back pain. Results: A total of 424 patients (145 with ASAS axial SpA, 81 with only a diagnosis of axial SpA, and 198 with chronic back pain); 64% of the total group were female, the mean ± SD age was 30.9 ± 8.1 years, and the mean ± SD symptom duration was 13.3 ± 7.1 months) were studied. In all patients, the strength of the associations between back pain and the PCS, back pain and the MCS score, and back pain and loss of work productivity were decreased by adding illness perceptions to the model, but explained variance improved. Adding coping to these models did not change the results. Comparable results were observed in all subgroups. Conclusion: Illness perception, but not coping, is important in the relationship between back pain and HRQoL and work productivity loss in patients suspected of having axial SpA, irrespective of subgroup. This finding suggests that targeting illness perceptions could improve health outcomes in patients suspected of having axial SpA