Vascular events in the Multiple Outcomes of Raloxifene Evaluation (MORE) trial: incidence, patient characteristics, and effect of raloxifene

Objective: To determine the incidence of arterial and venous thromboembolic (VTE) events, to determine the effect of raloxifene on the incidence of combined vascular (arterial and VTE) events, and to identify patient characteristics associated with these vascular events, in women participating in the MORE trial. Design: In a post hoc analysis using MORE data, arterial, VTE, and combined vascular event rates were compared between participants receiving placebo (n = 2,576) and those receiving 60 mg/d of raloxifene (n 2,557). Baseline characteristics were compared between those who did and did not experience an arterial event. The same analysis was performed for VTE events. Results: Overall, during a mean follow-up time of 41 months, 178 women experienced an arterial event and 40 experienced a VTE event. In the placebo group, the incidence of arterial events exceeded VTE events by at least sevenfold. Raloxifene had no significant effect on the incidence of combined vascular events in the overall cohort (hazard ratio 0.95, 95% Cl, 0.73-1.24). In a subset of women retrospectively determined to be at increased cardiovascular risk, raloxifene was associated with a lower incidence of combined vascular events (hazard ratio 0.63, 95% CI, 0.40-0.97). Baseline characteristics differed between those who did and those who did not experience an arterial event, but this was generally not the case for VTE events. Conclusions: Arterial events were more common than VTE events. The characteristics of women experiencing an arterial event differed from those experiencing a VTE event. Raloxifene had a neutral effect on the risk of combined vascular events in the overall population, and was associated with a reduced combined vascular event rate in women at increased cardiovascular risk. Additional studies are needed to confirm the effect of raloxifene on overall vascular outcomes.