The diagnostic delay in axial spondyloarthritis (axial SpA) remains unacceptably high, with one of the reasons being a late referral. Structured physician-based referral programs are able to improve early diagnosis, but lack of implementation is still an issue. The objective of this study was to evaluate an online self-referral (OSR) tool for patients with back pain and to compare it to an established physician-based referral tool.
Patients with back pain were included if they either fulfilled the requirements of the OSR tool or were referred by a physician using the Berlin referral tool. Rheumatologists in the specialized center performed a structured assessment in all patients that resulted in the final diagnosis of axial SpA / no axial SpA. Furthermore, we attempted to optimize the OSR tool in terms of maximizing the specificity constrained by a sensitivity of at least 90% of the original strategy.
361 consecutive patients (180 via the OSR and 181 via the Berlin referral tool) were included in the study. A total of 35 patients (19.4%) in the self-referral group and 71 patients (39.2%) in the physician-referral group were finally diagnosed with axial SpA. Axial SpA patients from the OSR group were more often HLA-B27 negative, females, and were more frequently at a non-radiographic stage as compared to axial SpA patients who came via the physician-based tool. Both groups had, however, a similar disease burden. According to the pre-defined selection criterion we identified an optimized combination of ≥2 IBP parameters and ≥1 other SpA parameters (in addition to both stem parameters).
Despite the better performance of the physician-based referral strategy, the proportion of axial SpA among self-referred patients (19.4%) was clearly higher than the assumed 5% prevalence of axial SpA in patients with chronic back pain. Based on our data driven approach the performance of the OSR strategy could be further improved if at least two IBP parameters plus one additional SpA parameter had to be present in addition to the stem parameters. The OSR tool can be used in specialized centers in addition to a physician-based referral strategy to improve early diagnosis and to increase awareness of axial SpA.