Source: Elmariah S, et al. Lancet 2014;385:792-98
Risk reduction provided by dual antiplatelet therapy (DAT) in the short-term interval (3-12 months) after coronary stenting is well established, and published guidelines provide consistent advice about appropriate duration of such therapy. In essentially every large randomized trial that has compared DAT to monotherapy, bleeding risks go up to a sufficient level that it counterbalances any risk reduction in reference to cardiovascular events. Indeed, two major mega-trials comparing DAT to monotherapy in stable patients with established vascular disease failed to demonstrate beneficial reduction in stroke (the MATCH trial) or stable coronary disease (the CHARISMA trial), but did find more bleeding risk.
Elmariah et al performed a meta-analysis of randomized, controlled trials employing DAT post coronary stenting to compare “short duration therapy” (i.e., ≥ 6 months) or aspirin alone with longer treatment.
Based on data from 14 clinical trials (n = 69,644), they found no evidence of improved outcome associated with longer duration treatment. While this may appear disappointing, one rationale for the investigation was the finding in the large DAPT Study (Dual Antiplatelet Therapy Study, n = 11,648) that non-cardiovascular deaths were actually increased if DAT was extended beyond 12 months, which was not confirmed in the meta-analysis.