Document resource
Introduction Anti-centromere antibodies (ACA) identify a distinct subset of systemic sclerosis (SSc) patients, traditionally associated with a less fibrotic phenotype and higher vascular risk. Their impact on immunosuppressive (IS) therapy persistence has not yet been clarified. The aim of this study is to evaluate whether ACA positivity influences IS continuation.Material and Methods We conducted a single-center retrospective case-control study on 90 SSc patients (M/F 4/86) treated with IS, 30 ACA+ and 60 ACA-, matched 1:2 for sex and age. At IS initiation (T0), clinical, demographic and investigational data were collected. Data on the first IS introduced and its clinical indication were also collected. Follow-up, extended up to 10 years or at least until the last available visit, allowed evaluation of tolerability and reasons for discontinuation. IS persistence was analysed using Kaplan–Meier curves, log-rank test and Cox regression.Results Baseline characteristics of the 90 patients are reported in table 1. At T0, mycophenolate (MMF) was the most prescribed IS in ACA- (47%), mainly for ILD (82%), while methotrexate (MTX) predominated in ACA+ (53%), used for cutaneous (44%) or articular involvement (56%) (table 2). During a median follow-up of 6 years (IQR 3–10), discontinuation of the first IS occurred in 8 ACA+ (27%) versus 7 ACA- (12%). In ACA+, MTX was the most frequently discontinued drug (62.5%) and the only one stopped due to clinical stability (25% of ACA+ discontinuations). In ACA-, discontinuation mainly involved MMF (43%), equally for intolerance, patient decision, and pregnancy (14.3% of ACA- discontinuations each), while malignancy was the cause of discontinuation in 28.5% of cases.IS persistence was significantly lower in ACA+ (log-rank p=0.016) (figure 1). In Cox regression, ACA positivity emerged as the only independent predictor of discontinuation (HR 12.26; 95% CI 1.65–133.4; p=0.014), whereas age, disease duration, mRSS, and FVC showed no significant associations.Conclusions While IS discontinuations were less common in ACA- patients, IS persistence was significantly lower in ACA+, with ACA positivity confirmed as the only independent predictor of early discontinuation. In ACA+, therapy discontinuation often occurred in conditions of clinical stability, in contrast to ACA- where major adverse events, especially malignancies, predominated; this finding highlights a different therapeutic profile that deserves further confirmation. Antibody stratification thus emerges as a useful tool not only for phenotypic definition but also for guiding personalized therapeutic strategies and identifying patients unlikely to benefit from prolonged IS exposure. Prospective multicenter studies are needed to confirm these results.Abstract P.276 Figure 1Kaplan-Meler curve: comparison of immunosuppressive therapy persistence between ACA+ and ACA- patientsAbstract P.276 Table 1Descriptive analysis of ACA+ and ACA- SSe patients at baseline (TO)Abstract P.276 Table 2Immunosuppressive drugs initiated at TO and their treatment indications in ACA+ and ACA- patients