Disease activity and widespread pain are main contributors to patient-reported global health in axial spondyloarthritis: an analysis of 6064 patients.

Global health (GH) and health-related quality of life are patient priorities in axial spondyloarthritis (axSpA). Our objective was to assess the relative importance of disease-related factors including disease activity, and patient-related factors including comorbidities, to explain GH in axSpA. Post hoc cross-sectional analyses of 4 sets (COMOSPA, PERSPA, COMEDSPA, and DESIR) of patients fulfilling ASAS criteria for axSpA. GH was assessed through the ASAS Health Index (ASAS-HI) or the EuroQoL-5D-3L (EQ-5D). Disease-related factors included disease activity (ASDAS, psoriasis, arthritis, enthesitis, and CRP), disease duration, diagnostic delay, bamboo spine, and treatment. Non-disease-related factors included sociodemographic characteristics, comorbidities and chronic widespread pain. Multivariable logistic and linear regressions and partial variances (R 2 ) were applied to identify independent determinants of GH. In 6064 patients (range 284-2756 across datasets), mean age ranged 38.9-45.8 years, 51-68% were male. GH was generally moderate: median ASAS-HI ranged 5.0-7.0. GH was explained by ASDAS (range of odds ratios, OR, 2.60-4.48) and chronic widespread pain (range of OR 2.19-8.39); other determinants included comorbidities and sociodemographic characteristics. Only 47-57% of the total variance in GH could be explained by the models; disease activity (partial variance, 16-26%) and chronic widespread pain (partial variance 12-15%) were the key contributing variables. A wide range of disease and non-disease-related variables usually collected in studies could only explain 47-57% of the variability in GH. Among these, disease activity and chronic widespread pain were most relevant and of similar magnitude of importance. These findings will be helpful for shared decision-making.