Therapeutic ratios predict asthma control in the ASTROLAB cohort

Abstract

Background: Inhaled corticosteroids (ICS) are the cornerstone of asthma therapy. The ICS-to-total-asthma-medication ratios (ICS therapeutic ratios) indicate suboptimal disease management in asthma. Aim: To verify whether therapeutic ratios predict asthma control in the ASTROLAB cohort. Method: ASTROLAB included UK and French persistent asthma patients (6-40 years) prescribed ≥6/12 months of asthma therapy. Patients were prospectively followed for ≥12 months, with 4-monthly asthma control assessments. Adults were administered the ACQ (score ranges 0-6, uncontrolled asthma cut-off score >0.75). Parents of children completed the RCP3Q (score range 0-9, cut-off score ≥1). Medication data from French claims (SNIIRAM) or UK prescribing (THIN) databases were used to calculate therapeutic ratios over 12 months before each control assessment. We compared the occurrence of uncontrolled asthma in patients with ICS therapeutic ratios Results: Among 773 patients (mean age = 22.2 years, 48.6% women) with 2,622 measurements, the risk of having uncontrolled asthma was significantly higher for patients with ratio Conclusion: In this study, low ICS therapeutic ratios reflected insufficient prescribing of ICS relative to all asthma therapy, which facilitated deterioration of asthma control.