Patients who suffer from one or more CVD epis
odes, such as myocardial infarction (MI) or ischemic stroke, are at very high risk for another CVD event. While Therapeutic Interventions, such as per-cutaneous coronary intervention (PCI), are aimed at stabilizing acute episodes, aspirin therapy may actually serve to prevent subsequent CVD events.
The American College of Cardiology and American Heart Association recommend low-dose aspirin for secondary prevention of coronary artery disease, but patients with aspirin allergies may not be able to follow this recommendation. they usually take other blood thinners that are more costly and sometimes less effective.
However, a new study reports that restricting aspirin from CVD patients who report aspirin allergies may unnecessarily deprive these patients of a safe, affordable protective choice. This study, which was published in the January 2016 issue of Current Allergy and Asthma Reports, shows that aspirin desensitization can be safe and successful in CVD patients with aspirin allergies.
Adverse reactions to aspirin are reported in 1.5 % of patients with coronary artery disease. The researchers differentiated between aspirin dose-related intolerance that do not call for desensitization (dyspepsia, gastric ulcers, and gastrointestinal bleeding)which do not require and will not benefit from aspirin challenge/desensitization, and true aspirin allergy.
Hypersensitivity reactions may be divided by their pathophysiological mechanism, either COX-1 inhibition (a non-immune mediated “class effect” likely to occur with aspirin or any NSAID) or a probable IgE-mediated reaction to a single NSAID. Aspirin is structurally distinct from other NSAIDs and rarely causes IgE reactions. Even the study authors said that all observed reactions to aspirin were noted to be a class effect rather than an IgE-mediated process
Patients with a history of aspirin reaction concerning for SJS/TEN ( Stevens Johnson syndrome and toxic epidermal necrolysis), DRESS (drug reaction with eosinophilia and systemic symptoms), serum sickness, or allergic interstitial nephritis, should be excluded from undergoing aspirin challenge. All others reporting a history suggestive of aspirin or NSAID hypersensitivity or those with an unclear history of reactions are candidates for rapid aspirin challenge/desensitization.
The study stressed that desensitization should be attempted before an urgent indication occurs, and the appropriate clinician to conduct the procedure is an allergist. Hemodynamically unstable patients should be stabilized before desensitization. Patients with a history of urticaria are less likely to be successfully desensitized, the researchers noted.
Suggested Approach to the Aspirin Sensitive Patient
Protocol to Increase Aspirin Dosing Above 81 mg Daily
With rare exceptions, patients reporting a history of adverse reactions to aspirin may be safely treated with aspirin after challenge/desensitization.
RESOURCES
Rapid Aspirin Challenge in Patients with Aspirin Allergy and Acute Coronary Syndromes. Current Allergy and Asthma Reports. http://www.ncbi.nlm.nih.gov/pubmed/26475526
Cardiology patient page: Aspirin. Circulation2012;125(10):e439–42. http://circ.ahajournals.org/content/125/10/e439.full
Use of Aspirin for Primary and Secondary Cardiovascular Disease Prevention in the United States. J Am Heart Assoc.2014; 3: e000989. http://jaha.ahajournals.org/content/3/4/e000989.full