POS0840 CLINICAL, ULTRASONOGRAPHIC AND RADIOGRAPHIC FEATURES’ IMPACT ON HAND FUNCTION IMPAIRMENT IN SYSTEMIC SCLEROSIS (SSc): A MULTICENTER CROSS-SECTIONAL STUDY

Background: Impaired hand function in SSc is a primary cause of disability and contributes to a diminished health-related quality of life. There is still a considerable amount of work needed to identify the main drivers of such disturbances from skin, vascular or musculoskeletal (MSK) damages. A better understanding would guide the management and allow to improve therapies. Objectives: To assess whether and which clinical, ultrasonographic and radiographic features from skin, vascular or MSK damages has an influence on hand function impairment in SSc. Methods: Between November 2022 and June 2023, consecutive patients were enrolled in a multicenter cross-sectional study. Clinical examination, hands and wrists' ultrasound and radiography were performed. Patient reported outcome's (PROs) included joint pain intensity, overall disease activity and Raynaud's phenomenon activity using a numerical rating scale (NRS) from 0 to 10. SSc specific global activity limitation was assessed by the scleroderma Health Assessment Questionnaire (sHAQ). Hand-specific activity limitation was measured using the Cochin Hand Function Scale (CHFS) and the HAnd scleroDerma lived Experience (HAnDE) scale. Pearson's or Spearman's (Rs) correlation coefficients or Mann-Whitney's, Kruskal-Wallis' and Welch's tests were adopted to explore the relationship between CHFS or HAnDE scale and continuous or categorical variables as appropriate. Multiple linear regression analysis was used to identify independent correlates of impaired hand function. Results: We included 73 SSc patients: 59 women, mean age 60.6±2.5 years, mean disease duration 9.6 ± 7.1 years. 36 patients had limited cutaneous SSc, 22 had diffuse cutaneous SSc and 15 were sine scleroderma. Median CHFS score was 6 (IQR 1.5-20.5), median HAnDE score was 23.5 (IQR 10.5-35.25) and median sHAQ score was 0.75 (IQR 0.33-1.11). Both CHFS and HAnDE scores significantly correlated with sHAQ (r=0.67 and 0.52 respectively, with p<0.001) and NRS (r= 0.38 and 0.66 respectively, with p<0.001) scores. In univariate analysis, CHFS and HAnDE scores showed a statistically significant correlation with mRSS at the time of evaluation, fingertip-to-palm distance, flexion contractures, telangiectasias, pitting scars and calcinosis. The presence of ultrasonographic tenosynovitis and of a pathological peritendinous Power Doppler signal and of radiographic acro-osteolysis were associated with higher PROs disability scores. In multivariate analysis, a statistically significant relationship between the presence of ultrasonographic tenosynovitis with Power Doppler signal and CHFS (17.6 [4.18; 45.2]; p 0.023) and HAnDE scores (26.6 [11.0; 42.2]; p <0.01) was confirmed. Furthermore, in multivariate analysis CHFS scores were significantly associated with the number of total ultrasonographic tenosynovitis (4.48 [-5.36; 9.33]; p 0.04), with the presence of calcinosis (10.2 [1.44; 19.4]; p 0.014) and with mRSS at the time of evaluation (0.491 [0.0955; 0.877]; p 0.025) and HAnDE scores were significantly associated with the presence of pitting scars (9.39 [1.91; 16.9]; p 0.015). Conclusion: We confirm a multifactorial origin of hand disability with various contribution of dermatological, vascular and MSK involvements, but we highlight for the first time that the extent and severity of MSK disease has primarily an impact on hand function impairment. This is raising the need to implement hand US assessment for monitoring SSc patients. This may guide future therapies and clinical trial outcome measures. REFERENCES: NIL. Acknowledgements: NIL. Disclosure of Interests: None declared.