Background/Purpose: The diagnostic delay in axial spondyloarthritis (axial SpA) has been reported to be 9 years and still remains unacceptably high. One of the major reasons for this delay is a late referral of patients with suspicion of axial SpA by primary care (PC) physicians, dealing with patients with chronic back pain (CBP). Physician-based referral programs have performed well in recognition of patients with high probability of axial SpA among CBP patients. However, there is still an unmet need for patients who do not receive a referral recommendation to a rheumatologist because of lack of awareness on the PC level. The objective of this study was to develop and evaluate an online self-referral tool for CBP patients with suspicion of axial SpA.

Methods: Patients with CBP were included in the Identification of the Optimal Referral Strategy for Early Diagnosis of Axial Spondyloarthritis (OptiRef) Study and assessed by a rheumatologist if they either

1) were referred by a physician using the Berlin referral tool (CBP>3 months and CBP onset<45 years of age + at least 1 of the following 3 parameters: inflammatory back pain (IBP), HLA-B27 positivity, sacroiliitis on imaging), or 2) completed an online self-referral and indicated the presence of CBP>3 months with onset<45 years of age + at least 1 additional SpA parameter. Rheumatologist then performed a structured assessment of SpA features and made the diagnosis of axial SpA/non-axial SpA.

Results: A total of 362 patients were included in the study on a 1:1 ratio either referred by a physician using the Berlin referral tool or via the online self-referral tool. A total of 71 patients (39.9%) in the physician-referral group and 35 patients (19.3%) in the self-referral group were finally diagnosed with axial SpA (p<0.001). Patients who were included via the online referral tool had a longer symptom duration, were more often females, less often HLA-B27 positive and had less often elevated CRP as compared to physician-referred patients (table 1a).

In patients diagnosed with axial SpA the patients referred by a physician were more often male (p=0.041), HLA-B27 positive (p<0.001) and showed more often advanced radiographic changes in the sacroiliac joints leading to the diagnosis of radiographic axial SpA (=ankylosing Spondylitis) (p=0.033). All other demographic and clinical characteristics did not differ between the two groups (table 1b).

Conclusion: The self-referral strategy resulted in the diagnosis of axSpA in 19% of the patients as compared to 40% with a referral done by a physician. However, the proportion of axSpA among self-referred patients was clearly higher than the expected 5% prevalence of axSpA in patients with CBP. The online self-referral tool can be used, therefore, in addition to a physician based referral program to improve the early diagnosis and to increase awareness of axSpA.