Problems With Handling Inhalation Devices in Airways Diseases

Management of asthma and chronic obstructive pulmonary disease (COPD) is very often best delivered with one or more inhalation devices. Unlike oral treatments, inhalation of medications requires the use of devices that patients must learn to self-administer. Until a decade or two ago, most inhaled medications could be delivered by a single device, the common metered dose inhaler (MDI). Today, each medication must be delivered by its own unique device, and the patient needs to learn how to use each one. Incorrect use of the device will lead to ineffective treatment, and all patients with asthma or COPD should receive instruction on the optimal use of the device.

The Study

A study by Molimard and colleagues^[1] is among several that have examined the effectiveness of inhaler use in patients with COPD who use one of six commonly used inhaler devices, namely Breezehaler®, Diskus®, Handihaler®, pressurized MDI, Respimat®, and Turbuhaler®. The investigators assessed inhaler use technique in 2935 patients using one or more of these devices during 3393 routine clinic visits. No instructions were given to the patients at the clinic visit, and inhalation errors that were considered device-specific were scored.

Significant inhaler handling errors were observed in more than 50% of handlings. Errors that were commonly observed were failure to insert a capsule or cartridge into the device, failure to press and release buttons, poor inhalation synchronization with failure to hold the device upright, and incomplete inspiration and breath-holding. No single device was more effective than any other device.

The study also found that patients who had "critical" inhaler misuse were statistically twice as likely to have experienced a COPD-associated hospitalization or emergency department visit in the previous 3 months. There was no finding that trained pulmonologists had better results than "untrained" general practitioners. The study authors concluded that inhaler handling errors are particularly common in patients with COPD and that training patients in the use of inhalation devices is crucial to outcomes. They recommend, again, that inhaler use should be taught to patients and reinforced regularly.

Viewpoint

This study suggests that better inhaler use may result in fewer hospitalizations or emergency department visits. This topic has been studied in the past with similar findings; however, the present study has the advantage of being of greater size than other studies. Moreover, this study compared the efficacy of the most commonly used and new devices in "the real world," and observations were made without preparing the subjects before the observation.

Patients were not told that their performance with the inhaler was being scored, which suggests that the result was likely to be similar to their performance at home. Clearly, an overall frequency of handling misuse of 50% is unsatisfactory and should be considered as a possible reason for treatment failure. Thus, rather than increasing the dose of the patient's treatment, perhaps the patient's inhaler technique should be addressed. There was not a clear finding that certain devices were better handled than other devices, signifying that the problem is not solely related to poor inhaler design. Regular reviews and frequent re-education about the use of inhaler devices with patients one-on-one may lead to better outcomes.^[2]