Need of education for dry powder inhaler storage and retention - a patient-reported survey.

Background: Dry powder inhalers (DPIs) are the most commonly used devices in asthma treatment in the Nordic countries. As new DPIs become available, patients are likely to be exposed to more than one type of device, with variable optimal handling. The aim was to examine real life storage and retention of multidose DPIs in patients with asthma.

Methods: This patient-reported survey on real life storage and retention of DPIs included asthma patients using multidose DPIs. Basic patient characteristics, information on inhaler use and storage, check of expiry date, and concurrent inhaler use was examined using an on line questionnaire.

Results: A total of 738 patients were included with a median age of 41 years, out of which 83 % were women. Sixty-three per cent reported storage conditions pre-defined as risk locations for their maintenance inhaler and 38 % of the responding patients had more than one maintenance inhaler in use at the same time. Two thirds of the study population checked inhaler expiry date less than monthly or not at all. Use after expiry date was frequently reported. Two thirds of the patients had not received information on DPI storage, either from their doctor and/or nurse or at the pharmacy.

Conclusions: This patient reported survey indicates that two thirds of the patients store their inhaler devices in suboptimal conditions, and only a minority had received instruction regarding inhaler handling. Non awareness of inhalers' expiry dates and use of more than one maintenance inhaler simultaneously was common. As inhaler mishandling may impact device functionality, improved communication and patient education is needed.