Predictors of Persistent Disease Activity and Damage in Systemic Sclerosis: Associations With Mortality in a Single-Center Cohort Study

Background/Objective The assessment of "disease activity"and "damage"has recently been standardized in systemic sclerosis (SSc), with the creation of composite indices. We aimed to identify predictors of persistent disease activity and moderate-severe damage in a monocentric SSc cohort and to evaluate the impact of persistent disease activity and moderate-severe damage on mortality. Methods Adult SSc patients with a disease duration ≤7 years were enrolled in this cohort study. Disease activity was evaluated by EUSTAR-AI (European Scleroderma Trials and Research Group Activity Index), severity by Medsger Severity Scale and damage by SCTC-DI (Scleroderma Clinical Trials Consortium Damage Index). "Persistent disease activity"was defined as EUSTAR-AI ≥2,5 in ≥50% of follow-up visits and moderate-severe damage as SCTC-DI ≥6. Statistical analysis was performed using Jamovi computer software. Results One hundred one SSc patients (85% females and 33% diffuse cutaneous SSc, with a median disease duration of 2 years; interquartile range, 1-5 years) were enrolled and followed up for a median time of 27 months (interquartile range, 14-48 months). Erythrocyte sedimentation rate (p = 0.004), Medsger Severity Scale (p = 0.044), and SCTC-DI at baseline (p = 0.022) were independent predictors of persistent disease activity. Severe organ involvement - interstitial lung disease, cardiac involvement, and pulmonary arterial hypertension - and diffuse cutaneous SSc were associated with moderate-severe damage at the end of follow-up. Persistent disease activity and moderate-severe damage were associated with poor survival (p = 0.0152 and p < 0.001, respectively). Conclusion Persistent disease activity and moderate-severe damage are associated with increased mortality in SSc. Early identification of at-risk patients may help improve outcomes.