REDUCTION OF REQUIREMENT FOR LEG VASCULAR-SURGERY DURING LONG-TERM TREATMENT OF CLAUDICANT PATIENTS WITH TICLOPIDINE - RESULTS FROM THE SWEDISH TICLOPIDINE MULTICENTER STUDY (STIMS)

Objective: To study the effect of long-term treatment of the platelet inhibitor ticlopidine as secondary prevention against the need of vasc ular surgery in patients with intermittent claudication. Design: The S wedish Ticlopidine Multicentre Study (STIMS), was conducted in six med ical and surgical clinics of university hospitals in Sweden. Methods: 687 claudicants were randomised to ticlopidine 250mg bd or placebo and vascular surgery events were recorded prospectively over a 7-year per iod. Cox proportional hazards models of risk for leg vascular surgery were constructed using drug treatment and II putative risk factors for vascular disease as covariates. Surgical event-free survivals were co mpared by Kaplan-Meier analysis. Results: The overall rate of first op erations was 2.4% per annum. More than half of these operations were i n the aortoiliac region. One-quarter of patients operated during the p eriod required further operations but amputation was rare. Ticlopidine treatment reduced the need for vascular reconstructive surgery by abo ut half, both in intention-to-treat and on-treatment analyses (unadjus ted relative risks 0.486, 95% CI 0.317-0.745: p<0.001; 0.493, 95% CI 0 .290-0.841: p<0.01, respectively). In Cox model analysis only male sex was confirmed as a risk factor for surgery. Previous peripheral arter ial surgery was the strongest predictor of the need for surgery. None of the risk factors examined interacted statistically with the effect of treatment with ticlopidine. Conclusion: In patients with intermitte nt claudication it seems possible to prevent the need for future vascu lar surgery by the use of platelet inhibition with ticlopidine.