P185 Does BASDAI score correlate to MRI changes in ankylosing spondylarthritis?

Abstract

Abstract Background/Aims The Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) is routinely used subjective outcome measurement of disease activity in Ankylosing Spondylitis (AS). BASDAI > 4 is used as a criterion for commencing anti-TNF therapy. Previous studies shown BASDAI correlation with MRI has been proven to be weak. We did this study to systemically compare clinical and radiological data of patients with AS and to look for the degree of correlation between BASDAI score and MRI changes positive for spondyloarthritis in our cohort of patients. Methods A retrospective analysis of AS patients attending Leicester spondylarthritis service at University Hospitals Leicester Trust (UHL) was carried out. Clinical characteristics such as HLA-B27 status, extra-articular features, family history of AS and CRP measurement were obtained from online systems and clinic letters. Online records were reviewed to see if patients had a MRI of the sacroiliac joints along with a BASDAI score at the time of MRI. Medcalc calculator was used for statistical analysis. Results A total of 106 patients were analysed with a mean age of 45.6 +/- 11.6 years (M = 62, F = 44) with mean BASDAI of 5.0 +/- 2.5. Mean CRP was 17.01+/- 30.4 (median CRP 6.5). 61% (n = 65) were HLA-B27 positive. 70 of 106 patients had a sacroiliac MRI scan which could be reviewed to a satisfactory level to determine whether disease is present or not. Two results were statistically significant when comparing active versus no active lesions on MRI: inflammatory back pain and anti-TNF therapy (Table 1). P185 Table 1:Comparison of clinical features in patients with active versus inactive lesions on MRI sacroiliac joint.Active lesions on MRI N = 45No active lesions on MRI N = 25P valueMean BASDAI (SD)5.0 (2.6)5.4(2.6)0.5Mean ASDAS CRP (SD)2.14(1.1)2.04(0.6)0.73Mean CRP (SD) mg/l14.7(21)17.8(33)0.645.5HLA-B2731180.Uveitis1190.3Inflammatory back pain40170.03Enthesitis820.3Peripheral Arthritis670.1Dactylitis010.2Psoriasis211Inflammatory bowel disease710.1Ethnicity: Caucasian37230.2Ethnicity: Asian820.3Age45.5 (10.2)50.5(11.3)0.06M: F26:1916:90.7Anti-TNF therapy1840.03BASDAI >428150.8BASDAI <417100.8BASDAI= Bath ankylosing spondylitis disease activity index, ASDAS= Ankylosing Spondylitis disease. CRP=C-reactive protein, HLA= human leucocyte antigen. Conclusion BASDAI score did not statistically correlate with the severity of inflammation as objectively observed on MRI. Only inflammatory back pain and anti-TNF therapy correlated with MRI disease activity. There was no difference in clinical features including HLA-B27 between patients with active and inactive MRI. Thus, BASDAI as a criterion for biologic therapy may need re-considering. Disclosure N. Jain: None. S. Byravan: None. J. Stairs: None. W. Rennie: None. M. Arumugam: Other; Speaker and Conference Fee MSD, Novartis, Abbvie.