LOAD: a pilot study of the safety of loading of aspirin and clopidogrel in acute ischemic stroke and transient ischemic attack

Abstract

Background: Most patients with ischemic stroke present to the emergency department beyond the approved 3-hour time window for thrombolytic or other revascularization therapies. Clopidogrel and aspirin loading is commonly used to prevent deterioration in other acute vascular occlusive events. This pilot study examined the safety of antiplatelet loading in acute ischemic stroke and transient ischemic attack.

Methods: Forty patients with stroke or transient ischemic attack symptoms, not eligible for revascularization, received a single dose of 375 mg of clopidogrel and 325 mg of aspirin within 36 hours of stroke onset. All patients were admitted to a comprehensive stroke department and monitored for neurologic deterioration (2-point increase on National Institutes of Health stroke scale [NIHSS] score) and bleeding complications until hospital day 7 or discharge. NIHSS was performed at 24 hours postadmission and on hospital day 7 or discharge, whichever came first.

Results: A total of 40 patients were loaded with 375 mg of clopidogrel and 325 mg of aspirin (mean 12 hours 32 minutes). Mean admission NIHSS score was 6. There were no cases of systemic hemorrhage or mortality. A single symptomatic intracranial hemorrhage (2.5%) was detected 43 hours posttreatment. When compared with matched control subjects, loaded patients were no more likely to experience hemorrhage and significantly less likely to experience neurologic deterioration (odds ratio 17.2; P < .002).

Conclusions: Loading with 375 mg of clopidogrel and 325 mg of aspirin appears to be safe when administered up to 36 hours after stroke and transient ischemic attack onset in this pilot study. Neurologic deterioration may be decreased and warrants further study.

Figure 1

Antiplatelets used after aspirin (ASA) and clopidogrel loading. In-hospital antiplatelet use postloading was at discretion of admitting practitioner. ASA (81 mg) and clopidogrel (75 mg) (A/C) was used during acute stroke admission then patients were transitioned (→) to long-term antiplatelet or anticoagulation therapy at discharge. A/D, Aspirin/dipyridamole ER.