Objective: Systemic sclerosis (SSc) is characterized by microvascular injury, fibrosis, and hypoxia of involved tissues. The vasoactive peptide endothelin-1 (ET-1) seems to be implicated in these events. Using nailfold videocapillaroscopy (NVC), we evaluated longterm effects of ET-1 antagonist treatment on nailfold microvascular damage in patients with SSc, over a 3-year followup period.
Methods: Thirty patients with SSc (mean age 64 ± 5 yrs, mean disease duration 8 ± 1 yrs) were recruited during their programmed standard treatment protocols. At baseline (T0), 15 patients with SSc (mean age 63 ± 15 yrs, mean disease duration 7 ± 3 yrs), already receiving cyclic intravenous infusion of iloprost (5 continuous days, average 80 μg/day, every 3 mo), continued the treatment for a further 3 years (ILO group). The remaining 15 patients with SSc (mean age 68 ± 13 yrs, mean disease duration 8 ± 4 yrs), although they continued the same cyclic intravenous iloprost treatment as the previous group, also received bosentan 125 mg twice a day for 3 years (ILO+BOS group). Qualitative analysis (scleroderma patterns) and semiquantitative scoring of the microvascular damage were performed by validated routine NVC methods.
Results: During followup, a statistically significant increase of capillary number was observed in the ILO+BOS group (p < 0.02), with a significant and progressive increase of angiogenesis (p < 0.01). In contrast, the ILO group showed a statistically significant decrease of capillary number (p < 0.05). After 3 years the number of capillaries was significantly higher in the ILO+BOS group than in the ILO group (p < 0.05). The score for giant capillaries decreased significantly in both groups of patients with SSc (p < 0.05).
Conclusion: In this open study, longterm treatment with ET-1 receptor antagonist in combination with iloprost was found to interfere with progression of nailfold microvascular damage in patients with SSc, as assessed by NVC over a 3-year followup period.