How to Monitor Disease Activity of Axial Spondyloarthritis in Clinical Practice

Purpose of Review: Treatment guided by periodic and quantitative data assessment results in better outcomes compared to using clinical gestalt. While validated generic as well as specific disease activity measures for axial spondyloarthritis (axSpA) are available, there is vast scope to improve their actual utilization in routine clinical practice. In this review, we discuss available disease activity measures for axSpA, describe results from the survey conducted among general rheumatologists as well as Spondyloarthritis Research and Treatment Network (SPARTAN) members about disease activity measurement in daily practice, and discuss ways to improve axSpA disease activity using technological advances. We also discuss the definitions of active disease and target for the treatment of axSpA. Recent Findings: The 2019 American College of Rheumatology (ACR)/Spondylitis Association of America (SAA)/Spondyloarthritis Research and Treatment Network (SPARTAN) axSpA treatment guidelines conditionally recommend the regular monitoring of disease activity using a validated measure such as Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) or Ankylosing Spondylitis Disease Severity Index (ASDAS). Assessment of Spondyloarthritis International Society (ASAS)-European Alliance of Associations for Rheumatology (EULAR) guidelines recommend ASDAS as the most appropriate instrument for the assessment of disease activity, preferably calculated using C-reactive protein (CRP). ASAS has selected a core set of variables which were updated recently and have been endorsed by the Outcome Measures in Rheumatology Clinical Trials (OMERACT) group in order to bring homogeneity in assessment of axSpA. In a recent study, Patient-Reported Outcomes Measurement Information System (PROMIS®) measures were able to discriminate inactive, moderate, and high–very high ASDAS activity groups. A newly developed semi-objective index P4 (pain, physical function, patient global, and physician global) correlates well with BASDAI and ASDAS in axSpA and can also be used for other rheumatic diseases in busy clinical practices. Summary: Regular disease activity monitoring is critical for long-term management of axSpA and shared decision-making. The integration of electronic health records and smart devices provides a great opportunity to capture patient-reported data. Automated capture of electronic patient-reported outcome measures (ePROMs) is a highly efficient way and results in consistent regular monitoring and may improve the long-term outcomes. While currently used measures focus only on musculoskeletal symptoms of axSpA, a composite disease activity measure that can also incorporate extra-articular manifestations may provide a better assessment of disease activity.