Characterization of aspirin allergies in patients with coronary artery disease.

Background: Aspirin prevents coronary thrombosis and is used extensively in cardiovascular prophylaxis. However, patients with a prior history of an aspirin "reaction" are routinely denied this medication.

Objective: To characterize the clinical presentation of a cohort of patients with coronary artery disease (CAD) and aspirin reactions.

Methods: Between 2009 and 2012, using a retrospective computer analysis, information was collected on all patients within a county-wide health care system presenting with CAD and a prior history of aspirin reactions.

Results: Of 9,565 patients with CAD, a prior history of aspirin reactions was recorded in 142 patients. Of these 142 patients, 30 (21%) had histories compatible with cutaneous and/or respiratory reactions. The other patients described adverse effects to aspirin, mostly gastrointestinal intolerance and bleeding. Aspirin-induced anaphylaxis was recorded in patients but may have been misdiagnosed, describing instead respiratory hypersensitivity reactions. Of the 142 patients, only 34 (24%) were receiving daily cardiovascular prophylaxis with aspirin. Of 108 patients not receiving aspirin, 25 (17.6%) were prescribed clopidogrel.

Conclusion: Histories of aspirin reactions in patients with CAD are uncommon, occurring in only 1.5% of our study population. The 21% of patients with histories compatible with aspirin hypersensitivities can be challenged and, if the results are positive, successfully desensitized. Moreover, almost all patients with gastric intolerance to aspirin can be treated with aspirin and a proton pump inhibitor. However, both approaches, which result in restoration of cardiovascular prophylaxis, were seriously underused in our study population.