AB0893 Influence of inflammation and structural damage on global functioning in patients with axial spondyloarthritis – using the asas health index in routine care
Authors: U. Kiltz, T. Wiatr, X. Baraliakos, J. Braun
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background</h3> Global functioning of patients with spondyloarthritis (SpA) can be influenced by many different factors. ASAS Health Index (ASAS HI) has aims to measure global functioning in patients with SpA. So far, its association with inflammatory spinal changes and structural damage has not been examined. <h3>Objectives</h3> To investigate the relationship between spinal mobility and self-report global functioning as assessed by the ASAS HI, and to study the influence of structural and inflammatory spinal changes on global functioning. <h3>Methods</h3> Patients from the outpatient clinic of our hospital suffering from axial or peripheral SpA completed questionnaires assessing disease activity and functioning (ASAS HI, pain, BASDAI, ASDAS, BASFI). Axial inflammation as detected by magnetic resonance imaging (MRI) was assessed by the Berlin score, structural damage by the modified Stokes ankylosing spondylitis (AS) Spine Score (mSASSS) and spinal mobility by the Bath AS Metrology Index (BASMI). Imaging were scored by two independent readers. Correlations between the ASAS HI and other health outcomes were analysed by Spearman's test. Logistic regression analyses were performed to investigate the association between functioning and other clinical characteristics. <h3>Results</h3> A total of 203 patients (76 non-radiographic (nr)-axSpA, 115 AS patients, and 12 with peripheral SpA (pSpA) were included: 63.5% male, mean (SD) age 46.6 (14.1), symptom duration 18.8 (12.8) years, and 76.4% HLA-B27 positive. The mean values of clinical assessments were ASAS HI 7.9 (4.0), BASDAI 5.0 (2.2), ASDAS 2.8 (1.1), BASMI 3.3 (1.8), pain 6.0 (2.6), and BASFI 5.0 (2.6). Elevated CRP levels were found in 37.4% of the patients, while 59.1% of the AS patients had syndesmophytes and 11.3% a bamboo spine. The median (IQR) mSASSS value was 3.8 (IQR 1.0–22.1) in AS und 0.0 (IQR 0.0–1.4) in nr-axSpA patients. The mean Berlin AS Spine Score for patients with axSpA was 5.3 (SD 7.1). Patients received a treatment with NSAIDs (62.7%), DMARDs (20.9%) and/or biologics (49.4%). A significant correlation of the ASAS HI was found for BASMI (r=0.5), BASDAI (r=0.7), ASDAS (r=0.5), BASFI (r=0.8), BMI (0.3) and Berlin Score (0.3). ASAS HI did not correlate with radiographic damage (mSASSS r=0.2, presence of bamboo spine r=0.2) and CRP (r=0.07). Stratifying patients by symptom duration (cut-off 3 years) did not affect these results. Logistic regression showed influence of obesity but not of inflammation or structural damage on global functioning (table 1). <h3>Conclusions</h3> The influence of obesity on functioning is remarkable in patients with SpA. In contrast, the influence of structural damage and spinal inflammation on functioning was limited in this study, probably due to the relatively low mSASSS and MRI scores. Further studies with inclusion of more severely affected patients are needed to study the association of functioning, spinal mobility, obesity and radiographic damage over a broader range of affected patients. <h3>Disclosure of Interest</h3> None declared