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. Author manuscript; available in PMC: 2022 Jul 1.
Published in final edited form as: Curr Opin Rheumatol. 2021 Jul 1;33(4):313–318. doi: 10.1097/BOR.0000000000000806

Educational Needs and Challenges in Axial Spondyloarthritis

Anand Kumthekar 1, Mohamad Bittar 2, Maureen Dubreuil 3,4
PMCID: PMC8667771  NIHMSID: NIHMS1696761  PMID: 33973547

Abstract

Purpose of review:

Axial spondyloarthritis (axSpA) affects 0.5–1% of the population in many regions of the world. This review summarizes the challenges in medical education around axSpA with attention to evidence around delayed diagnosis, clinician familiarity with typical axSpA features such as inflammatory back pain and adherence to accepted management principles.

Recent findings:

Clinicians who commonly manage patients with chronic back pain or other typical axSpA features are not consistently aware of the concept of inflammatory back pain and common extra-spinal manifestations. Further, clinicians may not be familiar with the non-radiographic spectrum of axSpA. Management of patients with possible axSpA does not consistently follow principles that would establish an axSpA diagnosis, and diagnosis of axSpA remains delayed by 6–7 years on average, with evidence suggesting management disparities on the basis of sex and race in some cases. Referral recommendations have increased the probability of axSpA diagnosis up to about 40% and, may complement educational efforts in axSpA

Summary:

Educational efforts in axSpA should focus on providing front-line clinicians with a better understanding of inflammatory back pain, the non-radiographic form of axSpA and accepted principles in axSpA management.

Keywords: Axial Spondyloarthritis (axSpA), Education, Diagnostic delay, Referral strategies

Introduction

Recent developments in axial spondyloarthritis (axSpA) have advanced our understanding of this complex disease. AxSpA is a spectrum of clinically related conditions that encompasses radiographic axSpA (r-axSpA; formerly called ankylosing spondylitis [AS]) and the more recently defined non-radiographic axial spondyloarthritis (nr-axSpA). While an ankylosing spondylitis is established through clinical findings and sacroiliac joint X-ray, nr-axSpA is diagnosed based on clinical grounds and a normal x-ray with or without evidence of sacroiliitis on MRI.1

The prevalence of axSpA differs geographically depending on multiple factors (e.g. HLA-B27 risk allele prevalence and race). The 2010 National Health and Nutrition Examination Survey (NHANES) estimated that, in the United States, axSpA prevalence is 1.4%, and r-axSpA specifically has a prevalence of 0.55%.2,3 Without effective treatment, up to 40% of those with nr-axSpA progress to the radiographic form over 10 years.4 Those with r-axSpA are at risk for syndesmophyte formation elsewhere in the spine, which results in reduced mobility and function.

Over the past two decades, major discoveries in SpA pathogenic mechanisms have led to the introduction of new treatment modalities, specifically those that target the TNF, IL-17/IL-23 and Janus Kinase pathways.5,6 In addition to the benefits of medications in controlling pain and disease activity, both observational and trial data suggests that TNF inhibitors, especially with early and prolonged use, may halt or at least slow radiographic progression.7–9 Limited data suggests that radiographic progression is also diminished with secukinumab.10

Given advances in identifying axSpA, and the effects of therapies in both controlling symptoms and preventing radiographic progression, it is imperative that those with axSpA are identified and treated early. However, some aspects of axSpA management remain suboptimal and, therefore form the basis for an educational agenda, which we will outline here.

The iceberg phenomenon: the gap between the expected and reported prevalence of axSpA

Low back pain is extremely common among adults.11,12 Inflammatory back pain (IBP), the cardinal feature of axSpA is characterized by morning stiffness, improvement with non-steroidal anti-inflammatory drugs (NSAIDs) and exercise, and worsening with rest. Although IBP is classically associated with axSpA, the presence of IBP alone is insufficient to establish an axSpA diagnosis. According to the NHANES survey, IBP was present in 5–6% of US adults, while spondyloarthritis prevalence was estimated at 0.4–1.4%.13,14,15 However, observational data have shown a much lower prevalence of diagnosed axSpA; data from the Northern California Kaiser Permanente group reported the prevalence axSpA was only 0.2%, with an AS prevalence of 0.1%.16 While the discrepancy between the estimated and observed prevalence of axSpA may be partly explained by study methods and/or geographical differences, this gap also raises concern for under-recognition of axSpA by clinicians. As with any disease state, some affected people will remain undiagnosed because they do not seek medical care, either because they perceive pain/stiffness as “normal”, or because symptoms remit spontaneously or with over-the-counter NSAIDs and or exercise.17 However, because management of axSpA also targets radiographic progression and comorbidities, it is critical that people with axSpA are identified and diagnosed early in order to optimize disease outcomes.

Clinician awareness of IBP and the axSpA spectrum is limited outside of rheumatology

Patients with chronic back pain often seek care from primary care physicians or general practitioners, osteopathic physicians, pain specialists, chiropractors or physical therapists. However patients with axSpA may also present with extra-articular features such as psoriasis, inflammatory bowel disease, or uveitis, prompting evaluation by a dermatologist, gastroenterologist or ophthalmologist. Therefore, it is prudent for clinicians within each of these specialties to be familiar with axSpA.

Unfortunately, data suggests that among general practitioners and clinicians who commonly manage back pain, knowledge of the axSpA spectrum and IBP features is poor. A study of general practitioners found that only 60% were aware that there was a difference between a mechanical and inflammatory back pain patterns. 18 Another study reported that only 5% of the primary care physicians were able to identify all features of IBP or the 4 key symptoms suggestive of IBP.21 Familiarity with IBP was better among chiropractors and osteopaths, but still imperfect with 23% reporting lack of confidence with the concept of IBP.19

Studies of non-rheumatologist clinicians who commonly evaluate back pain patients showed that while AS is well recognized and understood, the terms “axial spondyloarthritis and “non-radiographic” were less well known.20,21,19 For example, 75% of chiropractors and osteopaths were not familiar with non-radiographic axSpA in a 2019 study. 21 Further, accuracy in axSpA diagnosis and adherence to management guidelines is variable.22,23 A retrospective study showed that the majority of patients diagnosed with AS (63%) were diagnosed by a non-rheumatologist clinician rather than a rheumatologist. Of such patients, only 42% were found to have AS on a subsequent rheumatology evaluation.24 Further, a survey of primary care physician (PCP) and specialists identified inconsistencies in the perceptions and approach to the diagnosis and management of axSpA, including infrequently checking HLA-B27 among patients with IBP and lack of awareness about axSpA treatments.20,21 More than 20% thought that diagnosis of AS was a challenge and unmet need amongst PCPs.20

Poor awareness of axSpA and its key features is highlighted by the prolonged average time to axSpA diagnosis, which is a problem globally. As one example, a US-based study reported an average of 14 years delay between the onset of symptoms and axSpA diagnosis.25 Other studies suggested an average of 10 years delay, with axSpA tending to have longer diagnostic delay than psoriatic arthritis or rheumatoid arthritis. 26,27,28 Recently, Redeker and colleagues examined health insurance data from Germany, and reported a mean diagnostic delay of 6–7 years, from 1996–2015.29 Unfortunately, diagnostic delay was not reduced over time.

Taken together, the continued long diagnostic delay and gaps in axSpA knowledge among clinicians who are likely to encounter axSpA patients highlights need for improved education in axSpA among clinicians from multiple disciplines, and likely throughout their careers as scientific advances in pathophysiology and axSpA management continue to evolve.

Disparities in back pain and axSpA management

Beyond the diagnostic delay that exists generally for axSpA diagnosis, there is concern that further disparities may exist based on patient demographic factors (eg- sex, educational level, race/ethnicity) or based on other factors influencing access to healthcare (eg- health insurance, location of residence).

AxSpA has historically been thought to be more common in males compared to females by a ratio of 2–3:1, however this ratio is now known to be approximately 1:1. Although recognition of axSpA has increased in female patients, women are still under recognized and have higher average disease activity and reduced quality of life relative to males.30 Female patients have a significant longer delay in diagnosis (8.8 versus 6.5 years), and persistent clinician bias about axSpA being predominantly a male disease is a contributing factor.31 Additionally, differing disease presentations, slower radiographic progression and lower response rates to established therapies should serve as a focus of educational strategies to improve management of axSpA in female patients.32

Data also suggests disparities in management based on patient race/ethnicity. Literature on back pain more generally, has shown that despite back pain severity and interference being greater among Black and Hispanic Americans, members of these groups are less likely to be evaluated with advanced imaging, less likely to be referred for physical therapy and less likely to be prescribed opioid analgesics than Whites.33–38 Although the association of race and disease outcomes may be partly related to socioeconomic factors, a statistical analysis adjusting for each of these factors found that race was independently associated with back pain severity and interference.39 This raises concern that clinicians may under-recognize or under-appreciate the significance and burden of back pain in non-White patients.

A recent study by Singh and Magrey demonstrates that disparities in back pain management may also hold true in management of axSpA. This study, using data from a large US-based informatics platform, found that Black Americans with axSpA had greater disease activity and comorbidity burden than Whites with axSpA.40 While there may be true race-based differences in axSpA manifestations, another explanation is that clinicians missed axSpA diagnoses more commonly among Blacks with mild symptoms than among Whites with mild symptoms. One reason for these findings may be the central role of HLA-B27 in classification criteria and its relatively lower prevalence of HLA-B27 among Black and Hispanic Americans.41 However, given racial disparities in back pain management more generally, Singh and Magrey’s finding demonstrate a need to ensure that educational efforts in axSpA apply diagnostic and management principles equitably across racial and ethnic groups.

Strategies to improve recognition of axSpA

Because the diagnostic delay in axSpA remains a major challenge, several studies have examined strategies to prompt appropriate referral of patients with an increased probability of axSpA to rheumatologists.

The evidence for formal educational in axSpA is limited. Standardized patient cases simulating axSpA improved referral rates among general practice residents (+71% education group versus +15% control group). Authors of this study recommended such education in combination with a clinician referral tool targeted at SpA.42

The majority of data around clinician education on axSpA has assessed the effects of various referral strategies in clinical practice. Referral strategies in axSpA have generally focused on patients with chronic back pain (Table 1). It is necessary for referral strategies to have both high sensitivity and specificity, such that axSpA cases are not missed, and that rheumatology practices are not overburdened with evaluation of back pain patients. While, strictly speaking, referral strategies are not education, incorporating a referral tool into a clinical practice workflow or electronic health record, serves as a reminder to busy clinicians to consider axSpA among patients who meet referral criteria.

Table 1:

Studies examining referral strategies for axSpA.

Study: First author, publication year IBP as a referral criterion HLA-B27 positivity Sacroiliitis on imaging Axial SpA Diagnosis Number of participants Location(s) Ref.
Brandt, 2007 52.9% 51.7% 35.1% 45.4% 350 Germany 51
Hermann, 2009 90% 80% - 33% 92 Austria 52
Braun, 2011 100% 30% - 35.1% 322 Germany 53
Poddubnyy, 2011 (strategy 1) 78% 44.7% 55.7% 41.8% 318 Germany 43
Sieper, 2013 (strategy 1) 93.2% 27.8% 52.3% 35.6% 504 Multinational 44
Juanola, 2013 (strategy 1) 100% 11.7% 8.3% 25.4% 60 Spain 54
Haroon, 2015 (AAU patients) 62% 54% - 40% 72 Ireland 50
van Hoeven 2015 100% LBP 33.3% IBP 6.2% - 16.4% 579 Netherlands 46
Deodhar 2016 94% 49% 100% 46.8% 751 USA 25
Proft 2020 56.1% 56.9% 21.6% 59.8% - 19.4% 39.2% 180 OSR 181 BRT Germany 49
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IBP: inflammatory back pain; LBP: low back pain; Strategy 1 = Patients have to meet the criteria of chronic back pain (>3 months in duration) with an early age of onset (<45 years), in addition to at least one of the following: inflammatory back pain, HLA B27 positivity and sacroiliitis on imaging, in order to be referred to a Rheumatologist; AAU: acute anterior uveitis; OSR: online self-referral tool; BRT: Berlin physician-based referral tool.

The majority of studies on referral strategies have been done in Europe using varying definitions of IBP or components of IBP. Studies by Poddubnyy and Sieper (MASTER and RADAR) both included referral arms based on IBP, HLA-B27, NSAID response and family history of SpA; finding that the referral strategies resulted in axSpA diagnoses among about 40% of referred patients, a marked increase beyond the 5% expected probability of axSpA among those with chronic back pain.3,43–44 While it was expected that these simple referral strategies would be applicable across geographic locales, similar rules resulted in axSpA diagnoses among 33% of those referred in Hong Kong, and 16% of those referred from primary care providers in the Netherlands.45,46

In 2015, the Assessment of SpondyloArthritis international Society (ASAS) published recommendations for referral of patients with a suspicion of axSpA, including those with chronic back pain with a young age of onset, and at least one additional axSpA feature or parameter.47 When referral strategies were tested in observational axSpA cohorts, there was no strategy that combined high sensitivity and specificity, and it was recommended that the ideal strategy may vary by geographic region, depending on prevalence of each referral parameter.48

More recently, a study by Proft and colleagues in Germany evaluated a self-referral tool and found that 19% of patients who were self-referred using the online tool were subsequently diagnosed with axSpA. This proportion was lower than the 39% diagnosed with axSpA in the physician-based referral program, but still above the expected 5% prevalence of axSpA.49

There is limited data on the performance of referral strategies in the Americas. Deodhar and colleagues’ study in the US suggested that it is effective for front-line clinicians to refer patients with chronic back pain for ≥3 months beginning at age <45 years, and the presence of ≥1 of 3 SpA features, as this strategy resulted in axSpA diagnosis among 47% of those referred (specificity of 79% and sensitivity of 81%).25

Beyond chronic back pain populations, Dublin Uveitis Evaluation Too (DUET) is an Irish cohort that aimed to select patients with acute anterior uveitis (AAU) that might benefit from an evaluation by a rheumatologist.50 Approximately 40% of the AAU patients referred were subsequently diagnosed with axSpA. 50

Despite the fact that most of the tested referral strategies have increased the probability of early detection of axSpA, none of them have resulted in axSpA diagnosis in more than 50% of those referred. Given limitations in the Rheumatology workforce, it is necessary to continue to refine referral recommendations as a complement to broader medical education initiatives in axSpA. However, there are several key gaps in our understanding of the effects of educational interventions in axSpA beyond the context of referrals, and whether educational interventions benefit patient outcomes. It is not known if different intervention strategies are more effective than others in improving clinician knowledge. Finally, it remains unknown if a specific group of healthcare providers should be the focus of educational efforts in terms of efficiency, and optimizing axSpA patient outcomes.

Conclusion

Education on axSpA should be enhanced among healthcare providers globally. The evidence for this need lies in the continued years-long diagnostic delay for axSpA, which causes many patients to miss the “window of opportunity” to treat axSpA early and prevent radiographic progression, functional limitations and disability that comes with advanced disease. Clinicians across many disciplines are unfamiliar with the concepts of IBP and non-radiographic disease and there is variable application of accepted management principles.

Education in axSpA should be improved, given that axSpA prevalence is estimated at 0.5–1% in many locales, and that back pain is highly prevalent across the world. Outreach needs to target clinicians who care for patients with chronic back pain or other typical axSpA features. Education needs to highlight equitable implementation of management principles and referral recommendations, including application within groups in which axSpA may have been historically underrecognized. Clinicians need to have periodic educational updates as the scientific knowledge in axSpA continues to advance.

Key points.

  • Diagnostic delay in axial spondyloarthritis remains 6–7 years, and likely reflects under-recognition by clinicians

  • Many front-line non-rheumatologist clinicians who commonly manage patients with chronic back pain or other typical axial spondyloarthritis features lack familiarity with the concepts of inflammatory back pain and the non-radiographic spectrum of spondyloarthritis.

  • Medical education should be enhanced around axial spondyloarthritis, and healthcare systems should implement referral rules as a complement to education.

Acknowledgments

Financial support and sponsorship:

MD: NIH/NIAMS K23AR069127

Footnotes

Disclosures/COI:

Anand Kumthekar has nothing to disclose

Mohamad Bittar nothing to disclose

Maureen Dubreuil nothing to disclose

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