Understanding Axial Spondyloarthritis: A Primer For Managed Care

Axial spondyloarthritis (axSpA) is a chronic, immune-mediated, inflammatory condition consisting of 2 subsets that have been clinically defined as ankylosing spondylitis (AS) and nonradiographic axial spondyloarthritis (nr-axSpA). It is important to note that nr-axSpA is defined clinically by the absence of definitive x-ray evidence of structural damage to the sacroiliac (SI) joint by plain x-ray. Since the SI joint x-ray interpretation is subjective, the distinction between nr-axSpA and AS is not absolute. Sacroiliitis (inflammation of the SI joint) and inflammation of the spine are predominant features of axSpA, hence patients typically present with inflammatory back pain. Other manifestations, such as enthesitis, dactylitis, peripheral arthritis, anterior uveitis, psoriasis, and inflammatory bowel disease, are common. Despite an increased understanding of axSpA, unmet needs remain: most essentially, to improve the lengthy time to diagnosis after the onset of symptoms and to appropriate treatment. Patients and healthcare systems may incur substantial burden during the prolonged time to diagnosis or while patients are not receiving appropriate treatment for their axial disease. Prolonged time to diagnosis is related to difficulty in differentiating axSpA from common mechanical back pain, and absence of diagnostic criteria adversely affects the quality of care for axSpA. In addition, there are currently no diagnosis or billing codes for nr-axSpA, which poses an administrative challenge to identify and study patients affected. Patients with nr-axSpA have experienced a personal and societal disease burden similar to those of patients with rheumatoid arthritis and SpA conditions ( AS and psoriatic arthritis). Healthcare costs of axSpA are substantial, and the costs of lost productivity due to illness are estimated to be even greater. More options are needed in the management of the disease to prevent possible conversion of nr-axSpA to AS; to avoid structural changes that limit spinal range of motion and increase the risk of fracture and spinal fusion; and to reduce the economic burden to patients, healthcare systems, payers, and society overall.