Combination Therapy with Dipyridamole and Clopidogrel for Secondary Stroke Prevention in Aspirin-Intolerant Patients After Myocardial Infarction: Results of a Nationwide Case-Control Study

BACKGROUND AND PURPOSE: Combination therapy with dipyridamole and clopidogrel in stroke prevention and long-term outcomes in aspirin-intolerant patients with acute myocardial infarction (AMI) and previous stroke are unknown. This nationwide study analyzed the impact of dipyridamole and clopidogrel on secondary stroke prevention and long-term outcomes in aspirin-intolerant stroke patients after AMI. METHODS: This was a nationwide, case-control study involving 186,112 first AMI patients, 78,607 of whom had a previous history of stroke. In the final analysis, we included 4637 patients taking clopidogrel alone and 208 patients using a combination of clopidogrel and dipyridamole. RESULTS: The 12-year survival rate was not different between clopidogrel and clopidogrel–dipyridamole groups (log-rank p = 0.6247). Furthermore, there were no differences in event-free survival after stroke (log-rank p = 0.6842), gastrointestinal (GI) bleeding (log-rank p = 0.9539), or intracerebral hemorrhage (ICH; log-rank p = 0.6191) between the two groups. Dipyridamole did not contribute significantly to AMI survival (hazard ratio 0.98, 95% confidence interval 0.84–1.15), and did not show benefits in any of the subgroups regardless of sex, age (younger or older than 75 years), comorbidities, percutaneous coronary intervention, or medications. CONCLUSION: No differences were observed in the 12-year survival rate between clopidogrel and clopidogrel–dipyridamole groups. The two groups had balanced event-free survival in recurrent stroke, ICH, GI bleeding, and myocardial infarction.