A randomized feasibility study of the effect of ascorbic acid on post-angioplasty restenosis of hemodialysis vascular access (NCT03524846).

Restenosis remains a significant problem after angioplasty of hemodialysis vascular access. Both experimental and clinical studies have shown a protective effect of antioxidants against post-angioplasty restenosis. A prospective, randomized, feasibility study was conducted to investigate the effect of ascorbic acid to prevent restenosis. Ninety-three hemodialysis patients were randomized into three groups after angioplasty: placebo (n = 31), 300 mg ascorbic acid (n = 31), and 600 mg ascorbic acid (n = 31), treated intravenously 3 times per week for 3 months. Eighty-nine completed the clinical follow-up, and 81 had angiographic follow-up. In the angiographic follow-up, the mean (stand deviation) late loss of luminal diameter for the placebo, 300 mg, and 600 mg groups were 3.15 (1.68) mm, 2.52 (1.70) mm (P = 0.39 vs. placebo group), and 1.59 (1.67) mm (P = 0.006, vs. placebo group), with corresponding angiographic binary restenosis of 79%, 67% (P = 0.38 vs. placebo group), and 54% (P = 0.08 vs. placebo group). The post-interventional primary patency rates at 3 months were 47%, 55% (P = 0.59 vs. placebo group), and 70% (P = 0.18 vs. placebo group) for placebo, 300 mg, and 600 mg groups. Our results demonstrated that intravenous 600 mg ascorbic acid was a feasible therapy and might attenuate restenosis after angioplasty; however, its effect on post-interventional primary patency was modest.