Objective To determine the effect of low dose aspirin on ulcer healing in patients with venous leg ulcers.
Design Pragmatic, community based, parallel group, double blind, randomised controlled trial.
Setting Five community nursing centres in New Zealand.
Participants 251 adults with venous leg ulcers who could safely be treated with aspirin or placebo: 125 were randomised to aspirin and 126 to placebo.
Interventions 150 mg oral aspirin daily or matching placebo for up to 24 weeks treatment, with compression therapy as standard background treatment.
Main outcome measures The primary outcome was time to complete healing of the reference ulcer (largest ulcer if more than one ulcer was present). Secondary outcomes included proportion of participants healed, change in ulcer area, change in health related quality of life, and adverse events. Analysis was by intention to treat.
Results The median number of days to healing of the reference ulcer was 77 in the aspirin group and 69 in the placebo group (hazard ratio 0.85, 95% confidence interval 0.64 to 1.13, P=0.25). The number of participants healed at the endpoint was 88 (70%) in the aspirin group and 101 (80%) in the placebo group (risk difference −9.8%, 95% confidence interval −20.4% to 0.9%, P=0.07). Estimated change in ulcer area was 4.1 cm2 in the aspirin group and 4.8 cm2 in the placebo group (mean difference −0.7 cm2, 95% confidence interval −1.9 to 0.5 cm2, P=0.25). 40 adverse events occurred among 29 participants in the aspirin group and 37 adverse events among 27 participants in the placebo group (incidence rate ratio 1.1, 95% confidence interval 0.7 to 1.7, P=0.71).
Conclusion Our findings do not support the use of low dose aspirin as adjuvant treatment for venous leg ulcers.
Trial registration ClinicalTrials.gov NCT02158806.