ARGENTINE VALIDATION OF THE EULAR ACTIVITY INDEX: PRIMARY SJÖGREN'S SYNDROME (GESSAR, ARGENTINE SS STUDY GROUP)

Background: The EULAR Activity Index for primary Sjögren's syndrome was created in order to standardize the assessment of the systemic manifestations of the disease in clinical studies as well as in everyday practice.The scale includes 12 organ-specific domains, with different weights. In addition, each domain is classified in different levels of activity.The total score is obtained by multiplying the level of activity by the weight of each domain. Objectives: To adapt the index to the Argentine population. Methods: For validation, three Argentine rheumatologists adapted and translated to Spanish the original version in English and the final version was retranslated into English by a bilingual person. In order to estimate the constructive validity of the index, and due to the lack of a gold standard, the visual analogous scale (VAS) was used by experts, measured in a scale from 0 to 100 mm. Manifestations secondary to accumulated damage or to concomitant pathologies must be excluded.In the first visit, a comparison was made between the assessment of each domain with the VAS per domain, and between the global total score and the global VAS of disease activity. The VAS was performed by three specialists with more than 20 years of experience and by two specialists with 5 to 10 years of experience. Ten patients attended a 2nd visit in order to evaluate reproducibility, with no modifications in the treatment in relation to the previous visit. Statistical analysis: Continuous variables were expressed as medians with their interquartile range. Spearman's correlation coefficient was used in order to quantify the degree of correlation between the VAS and the score for each domain, and between the global VAS and the total score.The intraclass correlation coefficient was used to assess reproducibility. Results: The process included 51 consecutive patients, treated in the Rheumatology Service at Hospital Rivadavia; 49 (96.1%) were female and 2 (3.9%) were male; the median age was 58 (interquartile range (IQR): 49-69) and the median time of progression was 6 years (N: 44; IQR: 4-10.75). The median global VAS was 10 (IQR: 4-22.25) and the median total score was 5 (IQR: 3-9). The results of the correlation coefficient between the VAS and the scale for each domain were: constitutional symptoms: 0.46; lymphonodular: 0.76; glandular: 0.78; joint: 0.61; skin: 1; respiratory: 0.83; renal: 1; muscular:- (no patient had myositis); peripheral nervous system: 0.72; central nervous system: 0.67; hematological: 0.96;biomarkers: 0.86. The correlation between the global VAS and the total score of the scale was 0.79. The intraclass correlation coefficient was 0.67 (p: 0.06; 95% CI -0.32- 0.918) for the total score and 0.98 (p<0.01; 95% CI: 0.92- 0.995) for the global VAS. Conclusions: We found a good correlation in most domains and in the total score. Due to the simplicity and high degree of reproducibility of the VAS, we consider it a useful tool, especially for everyday practice. References: 1. Seror R, Ravaud P, Bowman S, et al. EULAR Sjόgren's Syndrome disease activity index (ESSDAI). Ann Rheum Dis 2010;69:1103–1109. Disclosure of Interest: None DeclaredCitation: Annals of the Rheumatic Diseases, volume 70, supplement 3, year 2011, page 299Session: SLE, Sjögren's and APS – clinical aspects (other than treatment) (Poster Presentations )