Short summary

The overall objective of the SPINCODE study is to set up an axSpA inception cohort among individuals with low back pain ≥ 3 months, who are considered at risk for axSpA. The investigators aim to explore the course of axSpA during the early stage of disease, assess outcomes, including novel imaging techniques, and identify predictive outcomes. Moreover, the investigators want to test the effect of a novel outpatient physiotherapist-coordinated rehabilitation intervention.

Rationale

Background: People with axial spondyloarthritis (axSpA) experience a diagnostic delay of 6.5 years in men and up to 8.8 years in women. One of the reasons for the diagnostic delay seems to be limited awareness of the disease characteristics among the referring health care professionals in primary care. By raising awareness about the disease, this study aims to reduce the diagnostic delay and promote early treatment. In addition to diagnostic and pharmacological treatment, physical exercise and rehabilitation are recommended in people with axSpA. In Denmark, people with axSpA are only offered free-of-charge physiotherapy when the disease has progressed to a stage with radiographic changes of the spine even though people in the early stage of axSpA report a similar disease burden. The overall objective of the Spondyloarthritis Inception Cohort of Southern Denmark (SPINCODE) is to set up an axSpA inception cohort among individuals with low back pain ≥ 3 months, who are considered at risk for axSpA. The investigators aim to explore the course of axSpA during the early stage of disease, assess outcomes, including novel imaging techniques, and identify predictive outcomes. Moreover, the investigators want to test the effect of a novel outpatient physiotherapist-coordinated rehabilitation intervention in people suspected of having axSpA. Aims: 1) To set up an axSpA inception cohort among individuals with low back pain ≥ 3 months in Southern Jutland counties who are considered at risk of axSpA. 2) To describe the epidemiology, demographics, clinical, laboratory, and imaging signatures in a population with low back pain suspected of axSpA and improve awareness about incipient axSpA. 3) To test the feasibility of a novel outpatient physiotherapist-coordinated interdisciplinary rehabilitation intervention for patients with low back pain suspected of axSpA. 4) To investigate the effect of a novel outpatient physiotherapist-coordinated interdisciplinary rehabilitation intervention (adjunct to pharmacological therapy) for patients with suspected axSpA compared to usual care: a randomized controlled trial 5) To compare those with and without a definite axSpA diagnosis after two years regarding pain, fatigue, mental and physical functioning, workability, physical activity levels, and quality of life.

Description of the cohort

The study consists of a medical part and a rehabilitation part. The medical part is planned as a prospective observational single-centre cohort study of consecutive patients with low back pain ≥3 months and ≤ 3 years, symptom onset at age 18-45 years and suspected of axSpA, referred from the Counties of Southern Jutland, and followed at Danish Hospital for Rheumatic Diseases (DHR) for a consecutive period of two years. To diagnose axSpA and improve diagnostic accuracy novel imaging techniques like low-dose computed tomography (ld-CT) and dual-energy computed tomography (DECT) are applied in addition to standard of care magnetic resonance imaging (MRI) of the sacroiliac joints (SIJ) and spine. The rehabilitation design is developed following the British Medical Research Council's framework for developing complex interventions. The design will be tested in a feasibility study, adapted as needed, and is planned to be tested in a randomized controlled trial (RCT) as add on to pharmacological treatment compared to no specialised rehabilitation. SPINCODE is overall a two-year observational cohort study. The rehabilitation study is a 6-month intervention study followed by a 18-month observational follow-up study. Primary Outcomes are the clinician's diagnosis of axSpA and health-related quality of life, assessed by the EuroQol-5-dimension 5 level-version (EQ-5D-5L).

Collaborating researchers and departments

Copenhagen Center for Arthritis Research (COPECARE), Center for Rheumatology and Spine Diseases Department of Clinical Medicine, University of Copenhagen

• Mikkel Østergaard, MD, Ph.d. Professor

Department of Medicine at the Hospital of South West Jutland, Esbjerg

• Oliver Hendricks, MD, Ph.d. Professor

Publications associated with the project

Knak, K.L.; Primdahl, J.; Kröber, G.; Fongen, C.; Graversgaard, J.; Bremander, A. Development of a Physiotherapist-Coordinated Interdisciplinary Rehabilitation Intervention for People with Suspected Axial Spondyloarthritis: The SPINCODE Rehabilitation Intervention. J. Clin. Med. 2024, 13, 6830.