This case series highlights the effect of abrupt discontinuation of long term aspirin in correlation with the risk of recurrent cerebrovascular events in twenty-one patient cases.

Aspirin is the mainstay of treatment for primary and secondary prevention of cardiovascular disease and secondary prophylaxis of cerebrovascular disease. Literature suggests that following chronic use, a “rebound” phenomenon can occur which causes a higher risk for recurrent ischemic events.

Patients from an outpatient neurology clinic were evaluated; baseline demographics and characteristics surrounding initial and recurrent events were assessed. Current medication regimen and dosing, symptoms and duration of event, compliance with antiplatelet medication, delay between antiplatelet interruption and onset of ischemic event, reason for discontinuation, and surgical history were examined. Likelihood of recurrent cerebral ischemia was based on age, blood pressure, cholesterol, diabetes, duration of symptoms, and smoking status.

Seven hundred and eighty-four patients with a history of stroke/TIA were screened. Twenty-one of these patients (57% male, 71±10 years) experienced stroke or TIA within one month following aspirin withdrawal; thirteen patients (62%) experienced a new stroke while eight experienced a new TIA (38%).  On average, 11.2±8.7 days separated aspirin discontinuation and recurrent event; six patients were unable to assign a numeric value to this duration (i.e., “a few days prior”). Surgery (n=5, 24%), other medical procedure (n=4, 19%), travel (n=4, 19%), running out of medication (n=2, 10%), aspirin side effects (n=2, 10%), dosing lapse (n=2, 10%), drug-drug interaction (n=1, 4 %), or clinician advised decision (n=1, 4%) encompassed reasons for discontinuation.

Twenty-one patients discontinued their antiplatelet medication and had a subsequent event in this case series; this appears high due to lack of prophylactic treatment. The risks associated with abrupt antiplatelet discontinuation need to be further studied to determine the interval of aspirin discontinuation that places patients at higher risk of recurrent ischemic event.