Inducing tolerance to aspirin—finally proven effective?
Published Online: April 25, 2014
Aspirin-induced asthma (AIA), also known as aspirin-exacerbated respiratory disease (AERD), is a distinct clinical syndrome consisting of asthma, rhinosinusitis with recurrent nasal polyps, hypersensitivity (intolerance) to aspirin (ASA) and other analgesics. Uncontrolled studies have demonstrated the beneficial effects of introducing aspirin tolerance (aspirin desensitization, AD) in such patients, which might be attributable to aspirin’s well-known and potent anti-inflammatory properties. However, prospective, double-blind, parallel-group, placebo-controlled studies assessing the AD effects in both aspirin-intolerant and aspirin-tolerant (ATA) patients were still pending.
In a pilot, double-blind, placebo-controlled study recently published in The Journal of Allergy and Clinical Immunology (JACI), Świerczyńska-Krępa and colleagues compared clinical and biochemical responses to a 6-month oral AD in 20 patients with AIA, and 14 patients with ATA.
Twelve AIA and 6 ATA patients received 624 mg of aspirin, whereas 8 AIA and 8 ATA patients received a placebo once daily for 6 months. Nasal and bronchial symptoms were reported by participants daily. Specific questionnaires assessing the course of rhinosinusitis (sino-nasal outcome test, SNOT20) and control of asthma (Asthma Control Questionnaire, ACQ), nasal (peak nasal inspiratory flow, PNIF) and lung functions (spirometry/peak expiratory flow, PEF), as well as inhaled corticosteroid doses were carefully evaluated by researchers on a monthly basis. Sinus computed tomography (CT) was done before and after AD. The levels of two mediators related to AIA, so called eicosanoids—namely leukotriene E4 (LTE4) in urine and prostaglandin (PG) D2 metabolite - 9α,11β-PGF in plasma—were also evaluated.
Only the AIA patients subjected to AD reported improvement of smell and reduction of sneezing and nasal blockage. The SNOT20 and ACQ scores of these patients decreased and their PNIFs increased. Their dosages of inhaled corticosteroids were reduced and no changes in point score of CT and the levels of eicosanoids following AD were found. In conclusion, the results of this study performed by Świerczyńska-Krępa and colleagues support the efficacy of oral aspirin desensitization, previously known from observational studies, and in addition prove that AD works only in aspirin-induced asthmatics.
The Journal of Allergy and Clinical Immunology (JACI) is an official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.