Objective Assessment of Adherence to Dry Powder Inhalers Attached with Flow Velocity Detection Devices in Asthmatic Children: a cohort study

Abstract

Background Suboptimal adherence to asthma medication is one of the major causes of asthma exacerbation. Currently, there is no report on the objective and scientific evaluation of medication adherence among asthmatic children. We aimed to identify and quantify adherence and techniques of using dry powder inhalers (DPIs) among pediatric asthmatic patients with a newly developed electronic device that can monitor the use pattern of DPIs during inhalation. Methods A prospective, single-center, observational cohort study was conducted. On discharge from the hospital, pediatric asthmatic patients were given Diskus DPIs with attached electronic devices. The frequency, flow velocity, volume, duration and angle were analyzed to determine the adherence and technical proficiency of DPI use. Results Pediatric asthmatic patients (n = 128) with a mean age of 7.8 years, a mean forced expiratory volume in 1 second (FEV₁) of 1.5 L, and a mean FEV₁% of 93.5% were recruited. Total 4096 results were recorded. The most common error types were short duration (98.8%), low volume (94.5%), wrong angle (33.3%), missed use (27.9%), low peak inspiratory flow rate (PIFR) (24.4%), exhalation (15.8%) and multiple use (0.8%). The mean actual adherence was 0.1% (standard deviation (SD), 0.9%). The errors in Diskus DPI use were correlated with asthmatic children's age, basic lung function, and desensitization treatment status. Conclusion Our study is the first to objectively characterize the primary types and proportions of technique errors among asthmatic children using modified Diskus DPIs and revealed that asthmatic children’s real-world actual adherence to DPIs was unsatisfactory.