Pos0681 revision in treatment decision might be necessary in seemingly inactive axspa patients according to basdai

Objectives To determine the frequency of inconsistency between the BASDAI and ASDAS-CRP cut-off values in disease activity categorization in patients with axial spondyloarthritis (axSpA) and to characterize the reasons for the discordance. Methods In total 575 axSpA patients (mean age: 40.2 ± 11.5; male gender: 358, 62.3%) followed up in a single center and who had both BASDAI and ASDAS-CRP scores at the same visit were included in this analysis. Of them 369 (64.2%) were classified as radiographic axSpA (r -axSpA). A BASDAI score of ≥4 and an ASDAS score of ≥2.1 were used as the cut-off value for the differentiation of inactive/active disease state. The demographic, disease related characteristics of the patients including structural damage were obtained. Results Inconsistency in the definition of the disease state according to two composite disease activity measures was found in 146 (25.4%) patients. As a consequence, the concordance rate of the two scales was calculated as 74.6% and corresponding κvalue was 0.458. Of the 274 patients who has inactive disease according to BASDAI, 46.4% were classified as active according to ASDAS-CRP (Figure 1). In our whole group; discordant patients for the disease state distinction according to two measures had higher CRP values, lower percentage of heel pain, and they were using less biologics. These patients also had lower BASFI, HAQ-S, and overall pain scores (Table 1). When we evaluated inactive patients according to BASDAI, discordant patients were significantly older, had lower education, higher serum CRP levels, and more frequently peripheral arthritis. Baseline mSASSS scores were higher in those discordant patients and more patients had syndesmophyte, additionally the progression rate according to mSASSS was higher. Conclusion In daily clinical practice discordance in the disease activity definition might be observed in around 25% of axSpA patients according to two widely used composite measures. The results of the present study suggested that patients with high serum CRP levels could be easily classified as inactive according to BASDAI and those patients might have developed more structural damage in disease course. Our results suggest that those patients misclassified according to BASDAI scale had worse functional status and quality of life. In conclusion ASDAS-CRP might be more appropriate disease activity measure in treatment decision. REFERENCES: NIL. Acknowledgements: NIL. Disclosure of Interests None Declared.