Comorbidities in Spondyloarthritis associate with poor function, work disability and quality of life: Results from the ASAS-COMOSPA study

Comorbidities add to the burden of disease and its complexity, and may prevent the achievement of treat-to-target goals. The objective of this study was to study the relationship between comorbidities and key disease outcomes in Spondyloarthritis, namely function, work ability and quality of life. Patients from the multi-national (22 countries), cross-sectional ASAS-COMOSPA study were included in the analysis provided they fulfilled the ASAS criteria. Data on comorbidities based on both self- and physician-report were collected through questionnaires and were subsequently used to compute the Rheumatic Disease Comorbidity Index (RDCI). Univariable and multivariable (adjusted for relevant confounders) multilevel (with country as a random effect) linear or logistic (as appropriate) regression analyses were conducted to investigate the relationship between the RDCI and: (1) functional ability; (2) work ability; (3) quality of life. In total, 3370 of 3984 (85%) patients recruited fulfilled the ASAS criteria: 66% were male, mean (SD) age was 43 (14) years, mean (SD) disease duration was 8.4 (9.5) years and mean (SD) RDCI was 0.7 (1.1). At least one comorbidity was reported in 51% of patients; 9% had ≥3 comorbidities. RDCI was independently associated with higher BASFI (β=0.37;95%CI [0.30,0.43]); lower EuroQol five dimensions questionnaire (EQ5D:β=-0.03; [-0.04,-0.02]); less work employment (OR=0.83; [0.76,0.91]); higher absenteeism (β=1.18; [1.04,1.34]) and higher presenteeism (β=1.42; [1.26,1.61]). Comorbidities in SpA adversely influence physical function, work ability and quality of life and are important to take into account in daily clinical practice. This article is protected by copyright. All rights reserved