Factors Associated With Diagnostic Delay in Axial Spondyloarthritis: Impact of Clinical Factors and Social Vulnerability

ObjectivePatients with axial spondyloarthritis (axSpA) often experience significant delay between symptom onset and diagnosis for reasons that are incompletely understood. We investigated associations between demographic, medical, and socioeconomic factors and axSpA diagnostic delay.MethodsWe identified patients meeting modified New York criteria for ankylosing spondylitis (AS) or 2009 Assessment of Spondyloarthritis International Society criteria for axSpA in the Mass General Brigham health care system between December 1990 and October 2021. We determined the duration of diagnostic delay, defined as the duration of back pain symptoms reported at diagnosis, as well as disease manifestations and specialty care prior to diagnosis from the electronic health record. We obtained each patient's Social Vulnerability Index (SVI) by mapping their address to the US Centers for Disease Control SVI Atlas. We examined associations among disease manifestations, SVI, and diagnostic delay using ordinal logistic regression.ResultsAmong 554 patients with axSpA who had a median diagnostic delay of 3.8 years (interquartile range 1.1-10), peripheral arthritis (odds ratio [OR] 0.65, 95% confidence interval [CI] 0.45-0.93) and older age at symptom onset (OR 0.83, 95% CI 0.78-0.88 per five years) were associated with shorter delay. AS at diagnosis (OR 1.85, 95% CI 1.30-2.63), a history of uveitis prior to diagnosis (OR 2.77, 95% CI 1.73-4.52), and higher social vulnerability (defined as national SVI 80th to 99th percentiles; OR 1.99, 95% CI 1.06-3.84) were associated with longer diagnostic delay.ConclusionOlder age at back pain onset and peripheral arthritis were associated with shorter delay, whereas uveitis was associated with longer diagnostic delay. Patients with higher socioeconomic vulnerability had longer diagnostic delay independent of clinical factors.