Published online: April 5, 2018
Elevated levels of blood eosinophils, an immune system component responsible for allergic reactions, have been associated with higher risk for future exacerbation and poor symptom control in patients with asthma. It is likely that there is a group of asthma patients with elevated blood eosinophils who will remain with uncontrolled symptoms and be at-risk for exacerbations despite good adherence to their inhaled corticosteroid (ICS) treatment.
In a recent article published in The Journal of Allergy and Clinical Immunology: In Practice, Papi and colleagues aimed to quantify and compare the occurrence of asthma exacerbations and the proportion of patients whose asthma symptoms remained uncontrolled, in both groups of patients who were adherent and non-fully adherent to ICS treatment.
The authors conducted a study using patient records from the Optimum Patient Care Research Database (OPCRD), a large database encompassing over 600 primary care practices across the UK, and from the iHARP, a global initiative database comprising approximately 5,000 patients from the UK, the Netherlands, Norway, Spain, Italy, Sweden, Australia, and France. Records of patients 18 years of age or older who were at-risk for an asthma exacerbation and had 2 or more prescriptions for ICS in the past year were extracted. The study utilized both patient-reported adherence collected from routine questionnaires as well as database recorded measures of adherence through the rate at which patients refilled their medication. Patients were considered to be adherent only when they had good adherence based on both patient report and database record.
The study identified 1,031 asthma patients with elevated blood eosinophils, of which only 178 (17%) had good adherence to their prescribed ICS therapy. The authors observed that there were larger proportions of adherent patients who had ≥2 asthma exacerbations (14.0% vs 7.2%) and uncontrolled symptoms (73% vs 60.8%) compared to patients who were not fully adherent towards their therapy.
The result of the study showed that adherence to prescribed ICS treatment was not associated with fewer asthma exacerbations or with better symptom control among asthmatic patients with elevated blood eosinophils. While increasing the dose of ICS may be the appropriate future treatment option, the authors suggest that prescription of treatments targeting other biological mechanisms could be a more beneficial treatment strategy for these patients.
The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.