POS1014 CENTRAL SENSITIZATION HAS MAJOR IMPACT ON QUALITY OF LIFE IN PATIENTS WITH AXIAL SPONDYLOARTHRITIS

Abstract

Background:Maintaining optimal health-related quality of life (QoL) is the ultimate goal of treatment in axial spondyloarthritis (axSpA). Chronic pain has a large potential impact on QoL. Central sensitization (CS) may explain part of the chronic pain in axSpA. However, the role of central sensitization (CS) herein has only been studied to a limited degree and current axSpA guidelines pay little attention to identification and treatment of CS.Objectives:To explore the relationship between CS and QoL in axSpA.Methods:Consecutive outpatients with axSpA from the Groningen Leeuwarden Axial Spondyloarthritis (GLAS) cohort were included. CS was assessed with the Central Sensitization Inventory (CSI; 0-100), QoL with the AS Quality of Life questionnaire (ASQoL; 0-18) and disease activity with the AS Disease Activity Score (ASDASCRP). A high probability of CS was defined as CSI score ≥40 and active disease as ASDASCRP score ≥2.1. Patient characteristics and clinical assessments were compared between groups with CSI score <40 and ≥40.(1) Multivariable regression analysis was conducted to investigate the relationship between CSI and ASQoL scores, correcting for potential confounders.Results:Of the 178 axSpA patients with available CSI score, 149 completed the ASQoL. Mean age of the 178 included patients was 47.4 ± 14.1 years, 78 (44%) were female, mean symptom duration was 21.4 ± 13.6 years and 88 (52%) were using bDMARDS. Mean CSI score was 38.0 ± 14.1, mean ASQoL 6.0 ± 5.3 and mean ASDASCRP 2.1 ± 1.0. CSI score ≥40 was significantly associated with higher mean ASQoL (9.7 vs. 3.3), higher mean ASDASCRP (2.6 vs. 1.7), female gender (60% vs. 29%) and more often entheseal involvement (61% vs. 26%) (Table 1).Table 1.Selection of patient characteristics, disease activity and clinical outcome variables for patients with axSpA, divided in subgroups for CSI score with a cutoff point of 40.CharacteristicsAll patientsn = 178CSI<40n = 98 (55%)CSI≥40n = 80 (45%)Age (years)47.4 ± 14.148.7 ± 15.045.8 ± 12.7Female78 (44)27 (29)44 (60)*Symptom duration (years)21.4 ± 13.621.5 ± 13.521.2 ± 13.8HLA-B27+133 (79)70 (79)54 (79)Smoker45 (27)28 (32)15 (23)BMI (kg/m2)26.7 ± 5.026.2 ± 4.427.5 ± 5.8Completed higher education181 (71)48 (70)34 (76)Biological use88 (52)49 (52)39 (51)RDCI (0-9)0.0 (0.0 – 1.0)0.0 (0.0 – 1.0)0.0 (0.0 – 1.8)Peripheral arthritis210 (6)5 (6)5 (8)Entheseal involvement364 (40)23 (26)38 (61)*ASDASCRP2.1 ± 1.01.7 ± 0.92.6 ± 1.0*CRP (mg/ml)2.9 (1.1 – 6.8)2.6 (1.1-6.0)3.6 (1.4 – 7.0)ASQoL (0-18)6.0 ± 5.33.3 ± 3.69.7 ± 4.9*CSI (0-100)38.0 ± 14.128.0 (23 – 34)50.0 (43.0 –56.0)N/AValues are n (%), mean ± SD or median (IQR).1International Standard Classification of Education (ISCED) level >4; 2Swollen Joint Count >0; 3Maastricht Ankylosing Spondylitis Enthesitis Score >0. *p<0.001. ASDASCRP: Ankylosing Spondylitis Disease Activity Score; ASQoL: Ankylosing Spondylitis Quality of Life questionnaire; CRP: C-reactive protein; CSI: Central Sensitization Inventory; RDCI: Rheumatic Disease Comorbidity Index.Patients with low ASDASCRP (<2.1) and also low CSI score (<40) showed good QoL (median ASQoL 1.1). Patients with low ASDASCRP combined with high CSI score (≥40) and patients with high ASDASCRP (≥2.1) combined with low CSI score reported worse QoL (median ASQoL 5.6 and 4.1, respectively). Patients with high ASDASCRP and also high CSI score reported the worst QoL (median ASQoL 12.0). (Figure 1).Figure 1.ASQoL score in patients with axSpA with CSI score ≥40 and <40, divided for ASDASCRP (cutoff 2.1)Additionally, in univariable analysis, the CSI score explained a large proportion of the variation of the ASQoL (R2=0.46). This association remained significant after correction for ASDASCRP, gender, symptom duration, entheseal involvement, smoking status, BMI category, educational level and comorbidities in multivariable analysis (CSI p<0.001).Conclusion:In daily clinical practice, CS seems strongly related to patient-reported QoL in patients with long-term axSpA.