Objective: To describe the natural history of ischemic digital ulcers (DU) in systemic sclerosis (SSc).
Methods: This single-center, retrospective, longitudinal study identified patients by demographic data, SSc history and type, Rodnan score, tobacco use, presence of autoantibodies, ongoing treatment, and DU history.
Results: One hundred three patients were enrolled, 46 with DU history and 57 without; 2 with DU were excluded. The mean duration of followup from the first non-Raynaud SSc symptoms was 12.3 +/- 6.3 years in patients with DU history and 12.1 +/- 7.0 years in patients without. In 43% of cases, first DU occurred within 1 year following first non-Raynaud SSc symptoms, and within 5 years in 73% of cases. In a multivariate analysis, younger patients at occurrence of first non-Raynaud SSc symptoms (HR = 0.77 per each 5 years older, 95% CI 0.66-0.90) with higher Rodnan scores (HR = 1.21 per 5 points, 95% CI 1.05-1.47) experienced earlier DU occurrences, which were delayed by vasodilator therapy (HR = 0.17, 95% CI 0.09-0.32). Patients with shorter durations between first and second DU episodes, particularly with a second episode within 2 years of the first, experienced a higher yearly incidence of DU episodes (0.85 +/- 0.57 and 0.48 +/- 0.26, respectively, if less or more than 2 yrs; p = 0.04). Throughout the duration of followup, the incidence of finger amputation was 1.2% per patient-year in patients with DU history.
Conclusion: Patients who are young at first sign of SSc, with high Rodnan scores and without vasodilator therapy, are at high risk of developing DU. Development of DU typically occurred within 5 years of the first non-Raynaud clinical symptom of SSc in the majority of patients.