Abstract 4549: Clopidogrel Discontinuation and Long-term Outcome After Percutaneous Coronary Intervention
Background Recent data suggest that the duration of clopidogrel treatment may influence clinical outcome after percutaneous coronary intervention (PCI), particularly in the case of drug eluting stent (DES) use.
Objective We evaluated the association between early and long-term outcome and duration of clopidogrel treatment.
Methods The RESEARCH/T-SEARCH Registry, a prospective observational cohort PCI study conducted between January 2000 and December 2005, provided detailed patient information on actual post-PCI antiplatelet therapy duration in 6200 consecutive patients, of whom 2200 received bare metal stents and 4000 were treated with DES. Endpoints were all cause mortality and stent thrombosis (ST).
Results Median duration of clopidogrel treatment was 4.7 months (interquartile range 2.6 to 6.1 months). Mean follow-up after clopidogrel discontinuation was 3.9 years (range 0 to 9 years). Angiographically confirmed ST occurred in 179 patients of whom 123 patients after DES. Clopidogrel discontinuation after 6 months (group II) was associated with lower mortality (adjusted HR 0.83; 95% CI 0.68 – 0.98) as compared with clopidogrel discontinuation after 3 months (group I). Clopidogrel discontinuation after 12 months (group III) was also related with lower mortality as compared with group I (adjusted HR 0.50; 95% CI 0.24 –1.00). Cumulative Kaplan-Meier mortality rates at 1-, 3- and 5 years were 4%, 9% and 14% in group I. At the same intervals we observed 3%, 7% and 11% mortality in group II, and 1%, 4% and 9% in group III respectively (logrank p<0.01).
Conclusion Extended use of clopidogrel after PCI may be associated with a reduced risk of mortality. The appropriate duration for clopidogrel administration, however, can only be determined within the context of a large randomized clinical trial.