Clopidogrel and Smoking Status Among Ischemic Stroke Patients: Smoker’s Paradox? (P1.122)

Objective: To investigate whether smoking status has a differential influence on the efficacy of clopidogrel vs. aspirin among stroke patients. Background: Published data suggest that after a myocardial infarction, active smokers have enhanced benefit with clopidogrel therapy compared with aspirin. Whether this ‘paradox’ exists in non-cardioembolic ischemic stroke patients is unknown. Methods: This single-center retrospective study assessed 1910 non-cardioembolic ischemic stroke patients discharged from hospital in 2013 and 2014, followed for 12 months post-hospitalization. Patients were categorized as smokers (defined as “at least half pack per day”) and Non-smokers. Primary outcome was a composite of ischemic stroke, myocardial infarction and all-cause death. Secondary outcomes were ischemic strokes (IS). ORs were computed for outcomes between clopidogrel and aspirin stratified by the smoking status while adjusting for vascular risk factors. Results: Among the cohort, 1066 patients were active smokers and 844 were non-smokers. Regarding the primary outcome, for smokers, rates were numerically much lower in clopidogrel vs. aspirin groups [12 (3.7[percnt]) vs. 50 (7.3[percnt]); adjusted OR 0.58, 95[percnt] CI: 0.31-1.07, p=0.28], but more congruent among non-smokers [7 (2.6[percnt]) vs. 14 (2.4[percnt]); adjusted OR 0.100, 95[percnt] CI: 0.39-2.53, p=1.00]. Similarly for the outcome of IS alone, among smokers, relatively lower rates were observed in the clopidogrel vs. aspirin group [12 (3.1[percnt]) vs. 34 (5.0[percnt]); adjusted OR 0.60, 95[percnt] CI: 0.31-1.18, p=0.14]; but a less pronounced difference between clopidogrel vs. aspirin was observed among non-smokers, [6 (2.2[percnt]) vs. 14(1.4[percnt]); adjusted OR 0.86, 95[percnt] CI: 0.32-2.29, p=0.77]. Conclusions: We found that ischemic stroke patients who actively smoked derived a slight yet non statistically significant benefit from clopidogrel compared to aspirin for vascular risk reduction. This issue needs to be further evaluated in additional studies of larger size. Disclosure: Dr. Zhang has nothing to disclose. Dr. Wang has nothing to disclose. Dr. Song has nothing to disclose. Dr. Ji has nothing to disclose. Dr. Hou has nothing to disclose. Dr. Cao has nothing to disclose. Dr. Dong has nothing to disclose. Dr. Huang has nothing to disclose. Dr. Feng has nothing to disclose. Dr. Ovbiagele has nothing to disclose. Dr. Wang has nothing to disclose.