Yvonne Bingham

and 7 more

Background: Adherence to inhaled corticosteroids (ICS) is suboptimal in school-age children with asthma. Little is known about adherence to ICS in preschool children with troublesome wheeze. Children with aeroallergen sensitisation, or those with multiple trigger wheeze (MTW), should be differential ICS responders. We hypothesised that adherence to ICS and symptom control are only positively related in atopic children, or those with MTW. Methods: Patients aged 1-5 years with recurrent wheeze prescribed ICS were recruited from a tertiary respiratory clinic. Clinical phenotype and aeroallergen sensitisation were determined, and adherence assessed using an electronic monitoring device (Smartinhaler®). Symptom control (Test for Respiratory and Asthma Control in Kids (TRACK)), quality of life (PACQLQ), airway inflammation (offline exhaled nitric oxide (FeNO)) were assessed at baseline and follow-up. Results: Forty-eight children (mean age 3.7 years, SD 1.2) were monitored for a median of 112 (IQR 91-126) days. At baseline n=29 had episodic viral wheeze (EVW) and n= 19 had MTW. 24/48 (50%) wheezers had sub-optimal ICS adherence (<80%). Median adherence was 64% (IQR 38-84). There was a significant increase in TRACK in the group as a whole, unrelated to adherence. When split according to ICS responders, a significant increase in TRACK was only seen in atopic wheezers with adherence >60%. There was no relationship between clinical phenotype, adherence and symptom control. Conclusion: Adherence to ICS was sub-optimal and was positively related to symptom control in atopic wheezers only. Assessments of adherence are important in preschool children with an ICS responsive phenotype prior to therapy escalation.