Understanding patient-reported disease burden in systemic sclerosis: key clinical and demographic features revealed by the EULAR Systemic Sclerosis Impact of Disease (ScleroID) Questionnaire.

Objectives: Systemic Sclerosis Impact of Disease (ScleroID) is a validated patient-reported outcome measure that assesses disease burden in systemic sclerosis (SSc). In this study, we aim to identify clinical and demographic features associated with disease burden reported by ScleroID. Methods: We investigated a multicentric SSc cohort with a cross-sectional and a longitudinal arm. We compared differences in ScleroID between demographic and clinical subgroups, and correlations with disease activity (patient-reported global assessment [PtGA] and physician-reported global assessment [PhGA]). Spearman correlation, Wilcoxon rank sum, Kruskal-Wallis, linear, and logistic regression were applied. Results: We included 471 patients (median age 57 years, 37% diffuse cutaneous SSc). In the adjusted multivariable model, work disability, lower educational level, a longer disease duration, severe dyspnoea, and oesophageal symptoms remained independently associated with higher patient-reported burden (corresponding to higher ScleroID scores). The ScleroID score strongly correlated with PtGA (ρ = 0.78, Conclusions: We identified demographic, clinical, and socioeconomic features associated with a high disease burden in SSc: longer disease duration, work disability and lower education status, severe dyspnoea, and oesophageal symptoms. Several health dimensions of ScleroID were affected simultaneously, highlighting the need for a holistic approach. ScleroID and objective clinical outcomes are complementary in identifying patient subgroups with a relevant disease burden and progression.