Prevalence and clinical relevance of digital ulcers in systemic sclerosis patients from the real-life: the experience of the SPRING Registry of the Italian Society for Rheumatology

Introduction: Digital ulcers (DU) are one of the most frequent manifestations in systemic sclerosis (SSc). The presence of DU seems to be a sentinel sign of internal organ involvement and is related to a poor prognosis of the disease. The aim of this study was to evaluate the prevalence and the relationship of DU with clinical manifestations/variants in a large SSc cohort from the SPRING registry. Methods: SSc patients fulfilling the ACR/EULAR 2013 classification criteria without missing data on digital ulcers were enrolled in a cross-sectional study. Logistic regression models were built to test the association between the presence of DU and SSc-related features. Results: Among 1873 eligible SSc patients, the presence of DU was significantly associated with gastrointestinal involvement (OR 1.88, 2.04 and 1.74; p < 0.001) and serum ATA positivity (OR 2.15; p < 0.001), as well as with telangiectasias, sclerodactyly, digital pitting scar, and calcinosis (OR 1.40, p = 0.005; OR 3.43, p < 0.001, OR 9.12, p < 0.001 and OR 2.77, p < 0.001; respectively). In the multivariable regression models, even after adjustment for covariates, ATA positivity (OR 1.76, p = 0.039), puffy fingers (OR 2.82, p < 0.001), and a higher revEUSTAR-AI (OR 6.63, p < 0.001) emerged as risk factors for the presence of DU. Moreover, a low presence of DU was recorded in SSc patients with a history of previous immunosuppressive treatments (OR 0.53, p = 0.032). Conclusion: In our Italian SSc cohort, DUs were significantly associated with the presence of puffy fingers, high revEUSTR-AI, and ATA seropositivity. Noteworthy, immunosuppressive treatments were associated with a low rate of DU, suggesting that they might contribute to the prevention of these harmful manifestations. Key Points center dot Digital ulcers were significantly associated with the presence of puffy fingers, high disease activity, and anti-Scl70 seropositivity. center dot Immunosuppressive treatments were associated with a low rate of digital ulcers, suggesting that they might contribute to the prevention of these harmful manifestations.