Time to diagnosis of axial spondylarthritis in clinical practice: signs of improving awareness?

S ir , The spectrum of axial spondylarthritis (SpA) ranges from symptoms of mild inflammatory back pain to the diagnosis of AS. This group of diseases affects the vertebrae, sacroiliac joints (SIJs) and their associated entheses with a pathophysiological process ranging from acute inflammation to an exaggerated repair process resulting in excessive new bone formation. This disease has the potential to lead to structural changes, deformity and loss of function. Historically there has been a significant delay in the diagnosis of axial SpA as a result of the lack of awareness of the early stages of the disease, lack of clinical findings on examination, inconsistent imaging findings and overreliance on radiographic changes to make a diagnosis. The most recent and comprehensive study by Feldtkeller et al. [ 1 ] reports an average time to diagnosis of 10 years. Such a delay in diagnosis results in prolonged periods of pain and disease activity without a diagnosis, loss of confidence in the ability of the medical system to diagnose and treat the disease and delay in the implementation of therapies that can effectively treat the disease symptomatically and potentially prevent radiographic progression [ 2 , 3 ]. The lack of diagnostic criteria facilitating the recognition of axial SpA and the poor awareness of the spectrum of disease across primary care has contributed to this well-recognized delay. The Assessment of SpondylArthritis International Society (ASAS) classification criteria has helped with the recognition of those patients with inflammatory back pain without radiographic changes by highlighting the importance of MRI in detecting early disease and also by recognizing disease without radiographic evidence of sacroiliitis [ 4 ]. Within the military, a specific back pain pathway for the aid of primary care doctors and community physiotherapists has been in place since 2009 ( Fig. 1 ). This promotes recognition of inflammatory back pain symptoms and axial SpA and also promotes early referral to Defence Medical Rehabilitation Centre (DMRC) Headley Court, a specialist rheumatology and rehabilitation facility for military personnel. This, in combination with the new diagnostic criteria for axial SpA, has resulted in a faster time to diagnosis of axial SpA compared with the previously published findings of Feldtkeller et al. [ 1 ]. Defence medical services: clinical management of low back pain MO: medical officer; LBP: lower back pain; DMRC: defence medical rehabilitation centre; SLR: straight leg raise; PCRF: primary care rehabilitation facility; RRU: regional rehabilitation unit; MIAC: multidisciplinary injury assessment clinic. A cohort of 138 service personnel with a diagnosis of axial SpA who attended the axial SpA inpatient rehabilitation and education course at DMRC Headley Court from March 2010 to November 2012 were reviewed as part of an assessment of the efficacy of the service in making a prompt and timely diagnosis. Information regarding age, time to diagnosis and radiological findings were retrieved from medical records. The mean age of patients was 35.2 years, 73.5% were diagnosed with AS, 20.5% with undifferentiated non-radiographic axial SpA and 6% with psoriatic spondylitis. X-ray of the SIJs was used to confirm a diagnosis of AS. MRI scanning of the SIJs or the SIJs and the spine was used in 78% of patients to assist in the diagnosis and assessment of disease. The mean time to diagnosis for all patients was 5.72 years (range 0–25) from symptom onset, with a mean age of diagnosis of 31.9 years (range 19–49) and a mean age at symptom onset of 25.8 years (range 10–48). The time to diagnosis between the sexes was quite markedly different, with SpA being diagnosed on average 3 years later in women (male 5.56 years, female 8.5 years). These data highlight a significantly reduced time to diagnosis of axial SpA/AS in this cohort of military axial SpA patients. The mean delay reported was 5.72 years, 4.3 years faster than the previously published landmark study [ 2 ]. These data were collected in a military population that is serviced by specialist outpatient clinics and inpatient rehabilitation services for axial SpA. The ASAS criteria have been fully embraced by the clinicians running the clinics and so has the role of MRI in making an early diagnosis and assessing disease activity and predicting prognosis [ 6 , 7 ]. An important element of this reduced delay in diagnosis is without a doubt the primary care education and guidance offered by the military back pain referral pathway. This is likely to have an even greater impact in a military population, given the effect back pain has on patients’ occupational capacity and the important emphasis that occupational medicine plays in all primary and secondary care military consultations. Time to diagnosis in axial spondylarthritis has significantly improved since Feldtkeller et al. ’s 2003 study. Funding : None. Disclosure statement : The authors have declared no conflicts of interest.