Collaboration between rheumatologists, primary care reduces delay in axial SpA diagnosis
Partnerships between rheumatologists and specially trained advanced practice providers in primary care can reduce diagnostic delay and shorten wait times in axial spondyloarthritis, according to data published in Arthritis Care & Research.
“Arriving at a diagnosis of axial spondyloarthritis is associated with significant delay of up to 9 years for patients diagnosed with ankylosing spondylitis, the more advanced form of axSpA that can lead to structural changes seen in the pelvis and spine,” Laura Passalent, PT, BScPT, MHSc, ACPAC, and Y. Raja Rampersaud, MD, FRCS(C), both of the University of Toronto and the University Health Network, told Healio Rheumatology in a statement. “This delay often results in significant pain, spinal immobility and reduced function and quality of life.”
“Axial SpA that has not yet manifested in structural changes but demonstrates early inflammatory changes identified on MRI is referred to as non-radiographic axial SpA,” they added. “The earlier patients can be identified with axial SpA, particularly non-radiographic axial SpA, the earlier they can start effective treatments that can curb the irreversible structural changes seen in advanced axial SpA.”
To evaluate such a screen process for early axial SpA identification, Passalent and colleagues conducted a prospective observational study of adults with back pain who were seen through the Spine Assessment and Education Clinics (ISAEC) program. According to the researchers, ISAEC is a government-funded interprofessional model for chronic lower back pain based on a network of primary care and centralized tertiary care providers in Ontario. The program makes use of advanced practice clinicians — physiotherapists and chiropractors — working in primary care settings.
Adult primary care patients with lower back pain who were referred to the ISAEC program underwent a standardized screening for inflammatory back pain, where they were assigned a risk score based on the Assessment of Spondylarthritis International Society (ASAS) criteria. Those who had experienced lower back pain for more than 3 months and were aged younger than 50 years at onset were then referred to a comprehensive secondary screening, where they were assessed by one of two physiotherapists with advanced rheumatology training.
These physiotherapists had an average of 13 years post-licensure clinical experience at the start of the study period and were affiliated with the Toronto Western Hospital’s Spondylitis Program. Patients who presented at the secondary screening were determined to have a low, medium, or high risk of axial SpA, versus no risk. Precision and accuracy were then measured against a rheumatologist with axial SpA expertise, who provided a final diagnosis. A total of 405 patients underwent primary and secondary screening.
According to the researchers, human leukocyte antigen (HLA)-B27 was present in 14.4% of patients who completed both screenings. Median wait time from primary to secondary screen was 15 days. The rheumatologist determined 64.9% of patients to have no or low risk for axial SpA, and 35.1% to be of medium or high risk.
In their analysis, Passalent and colleagues found that the best combination of sensitivity (68%), specificity (90%) and positive (80%) and negative (84%) predictive values was found with in the secondary screening. Ultimately, 15.6% of patients received a final diagnosis of axial SpA. The median delay from first onset of lower back pain to final diagnosis was 2 years for non-radiographic disease and 7 years for ankylosing spondylitis.
“A key result from our study was the median time to diagnosis was reduced to 2 years for non-radiographic axSpA and to 7 years for ankylosing spondylitis,” Passalent and Rampersaud said. “The early identification of non-radiographic axial SpA is critical as this allows for early introduction of evidence-based management to delay disease progression and optimize outcomes in this patient population. It is expected these timeframes will further reduce, as the model matures over time.”
“Our networked interprofessional model has demonstrated similar clinical and system impact for surgical referrals and provides a scalable framework for other areas of musculoskeletal assessment where there are challenges around access to care and diagnostic delay,” they added. “In short, our networked interprofessional model has proven to be an effective bridge between primary care and specialty musculoskeletal care.”