The present study has evaluated the patients’ journey to diagnosis and their healthcare utilization after diagnosis in a large sample of more than 5000 patients with axSpA from 27 countries worldwide. With respect to the patient journey, patients with axSpA had visited more than two HCPs prior to diagnosis, with a higher frequency of general practitioner (GP) and rheumatologist visits, as well as performing more frequent tests, such as HLA-B27, x-rays, and MRI scans. Finally, the rheumatologist diagnosed seven out of ten of these patients; all this with a diagnostic delay of more than 7 years. Regarding healthcare utilization after diagnosis, 95% of the patients had used at least one healthcare resource during the last year, with an average of 29.2 healthcare resource uses per year, highlighting healthcare visits, medical tests, emergency visits, and hospital admissions. Furthermore, being younger or female, and having longer diagnostic delay, higher disease activity, poorer mental health, greater functional limitation, and greater spinal stiffness, were associated with higher healthcare utilization. In addition, regional differences have been found with respect to patient journey and healthcare utilization.

HCPs Seen Before Diagnosis

In the majority of IMAS regions, patients with axSpA had visited the GP more frequently before diagnosis, except in the Asian region, where patients had visited the orthopaedic specialist more frequently. This may be because chronic back pain is a frequent symptom of patients who visit both GPs and orthopaedic specialists [21], or due to the fact that primary care physicians often overlook the symptomatology of axSpA, as well as the opportunity to diagnose or refer patients with axSpA to rheumatologists, referring them directly to other specialists, such as orthopaedics, spine surgeons, or rehabilitation specialists [22, 23].

In addition, this increased number of medical and orthopedic consultations prior to diagnosis and the fact that patients are not referred to a rheumatologist earlier may be due to the small number of rheumatology specialists in regions such as South Africa, which has only 85 rheumatologists for nearly 56 million people [24]. Although the number of rheumatologists is higher in high-income countries [25], there are inequalities and shortages in the number of rheumatologists worldwide, which represents a serious challenge for the increasing large number of patients with rheumatic diseases.

Test Carried Out Before Diagnosis, HCP That Made Diagnosis and Diagnostic Delay

The HLA-B27 test was the most frequently used test for diagnosis of patients in IMAS, being conducted more frequently in South Africa and less frequently in Asia. While tests such as MRI scans and x-rays were performed more frequently in Europe and North America. This could be due to the fact that higher-income regions, such as Europe and North America, have greater access to imaging tests such as MRI or CT scans, while less expensive tests (e.g., HLA-B27) are more often used in regions such as South Africa. Also, the differences in prevalence or access to B27 carriership could explain different practices from HCPs requesting this. In the case of Asia, perhaps this lower use of diagnostic tests is due to the fact that most of the patients in the Asian region from IMAS were male, who until recently have been thought to be the most likely to suffer from axSpA [26].

Finally, the rheumatologist diagnosed most of these patients, although in the Asian region the orthopaedic specialist also played an important role in the disease diagnosis. This may be because orthopaedists can more easily distinguish axSpA from chronic back pain than other HCPs [21]. However, this could also be because most patients with chronic low back pain are referred to this specialist, given the greater presence of orthopaedics compared to rheumatologists, but also to differences in their qualifications between countries.

Despite, or because of, all of these HCPs visits and diagnostic tests during the patient journey of patients with axSpA, a diagnostic delay of more than 7 years for patients with axSpA in IMAS is evident. This unacceptable diagnostic delay is associated with poor health factors, such as greater disease activity or worse treatment response [27, 28]. Therefore, educating primary care physicians and other HCPs about axSpA is essential, and, together with knowing when to make a referral to a rheumatologist, should reduce the long diagnostic delay in patients with axSpA [29, 30]. Furthermore, these longer diagnostic delays were associated with an increased clinical, economic, and social and psychological burden [31]. Therefore, a generalized approach to the education of professionals and a more accurate calculation of the economic costs of axSpA for healthcare are essential.

Healthcare Utilization After Diagnosis by Region

After diagnosis and during the last 12 months prior to the survey, patients had used on average 29.2 healthcare resources, which included health visits, medical tests, emergency room visits. or hospital admissions, with only 5% of survey respondents not having used any of these resources. The regions with the highest number of healthcare visits and/or tests were Europe and Latin America, while Asia had the patients with the lowest healthcare utilization. Similarly to patients in IMAS, a previous study showed that most patients were seen at least once a year by a rheumatologist [32], although approximately half the patients visited another specialist, with an average of two visits per year [33]. In addition, one out of three patients usually visited a general practitioner [34]. We acknowledge this high amount of healthcare utilization could be due to high levels of the patients’ disease activity, as some studies have shown that patients with more visits to the general practitioner or physiotherapist and more hospital admissions or outpatient visits had greater disease activity [32, 34].

The Role of Physiotherapist

It is worth noting the large number of visits to physiotherapists, especially in Europe, Latin America, and South Africa, after diagnosis (one in three patients) and before diagnosis (21.3, 12.5, and 12.2 visits, respectively). In this regard, physiotherapeutic interventions for axSpA have been shown to be an integral part of the treatment of the disease, and effective in improving spinal mobility in the short term [35]. In addition, a recent study has shown that a high rate of patients with axSpA see a physiotherapist or would like to do so [32], as it is one of the Assessment of SpondyloArthritis international Society (ASAS) recommendations for managing patients with axSpA [36]. Thus, frequent visits to a physiotherapist should be part of the integral management of patients with axSpA.

Healthcare Utilization After Diagnosis and Costs Related to axSpA by Countries

The average healthcare number of visits in the IMAS cohort was 29 times, being higher in countries such as Brazil (50), France (48), Spain (42), and Norway (32), while countries such as Costa Rica, UK, India, Slovenia, Austria, or Taiwan were below 20 visits. All this healthcare utilization before and after axSpA diagnosis involves a significant level of cost to the patient and to the healthcare system. A study of patients with axSpA in the UK showed a total cost during 3 months of £2,802 [34], annual cost per patient of US$6,600 for Colombian patients with axSpA [37], or €11,462.3 for Spanish patients with axSpA [38]. Besides the costs associated with healthcare resources, patients with axSpA suffer significant indirect economic costs associated with self-funded healthcare, work absenteeism, and early retirement [39,40,41], as well as high drug treatment costs generating a considerable burden on health systems and governments of each country [42, 43]. In this sense, treatment is considered the most important contributor to direct costs of patients with axSpA, especially for patients with higher disease severity and those with a poor response to conventional disease-modifying antirheumatic drugs (cDMARDs) [44].

In our IMAS cohort, younger patients, women, those with higher disease activity, poorer mental health, greater functional limitation, greater spinal stiffness, and longer diagnostic delay experienced higher healthcare utilization. This statement is consistent with the Spanish sub-sample of IMAS [45]. However, these results should be interpreted with caution, as we cannot establish a cause–effect relationship between healthcare utilization and clinical factors of patients with axSpA in the IMAS cohort.

Assessing the healthcare utilization of patients with axSpA is essential to identify the profile of patients who require higher utilization due to their disease, as well as to evaluate how worse disease outcomes lead to higher utilization of healthcare resources, resulting in increased healthcare spending. In addition, optimal disease care, management, and treatment can help reduce the number of visits and tests, with positive consequences on allocated resources. In this regard, although radiography is the most cost-effective imaging test for the initial diagnosis of sacroiliitis in patients with inflammatory low back pain suspected of axSpA [46], MRI of the sacroiliac joints has become the main tool for the early diagnosis of axSpA [47].

Comparing IMAS regions, the diagnostic delay of patients in South Africa and North America was close to 10 years, while in Asia it was 4. Furthermore, South Africa and Latin America were the regions with the highest proportion of patients with physical comorbidities, highest disease activity, and greatest use of NSAIDs and csDMARDs. Finally, spinal stiffness and functional limitation was higher in Europe, North America, and South Africa [16]. The present study has shown that the regions with the highest 1-year healthcare utilization were Europe, Latin America, and South Africa, which is consistent with the disease findings previously mentioned. However, it is important to note that, although it is not possible to establish cause–effect relationships between phenotypic characteristics and healthcare utilization, the results point in the expected direction.

Strengths and Limitations

IMAS is the most extensive survey of patients with axSpA, including 5557 respondents from 27 countries worldwide, making it the largest sample and coverage to date. This study identifies a significant number of variables in the patient journey and healthcare utilization, knowledge of which can help to quantify the cost before and after axSpA diagnosis and can help to inform the patient care pathway. However, IMAS has some limitations. First, the survey was based on self-reported data and  the diagnosis of patients could not be confirmed. Secondly, information on healthcare visits and tests carried out were self-reported by patients so can only ever be an estimate. Another limitation is the fact that we only have global information on the complementary tests, but do not know specific information, such as for which anatomical regions the imaging tests were performed or which specific determinations were requested for the laboratory tests. Furthermore, 70 of 5272 (1.3%) patients who reported healthcare utilization may have had the disease for less than 1 year and their assessed healthcare utilization may be lower, although closer to 12 months. In addition, results on disease severity, such as BASDAI scores, GHQ-12, spinal stiffness, and functional limitation should be interpreted with caution, as this information was self-reported and may suffer from self-reporting bias, as respondents often tend to introduce bias as they find it difficult to recall past behaviors [48]. Finally, there is an over-representation of patients from the European region compared to other regions such as Asia or South Africa. The unbalanced samples within each of the countries and regions represent a limitation of the study and, therefore, comparisons between countries and regions should be interpreted with caution.

This IMAS study has shown how the region and country of residence of a patient with axSpA influences the time waited for diagnosis and the management of their disease, although there are other geographical and socioeconomic aspects such as the place of residence (urban-rural), the distance to a rheumatologist, the type of health coverage available, and the economic status of the patient.