Study: Half of Patients Make "Critical Errors" When Using Inhalers

A new study looking at incorrect usage of inhaler use among patients with obstructive lung diseases suggests more work needs to be done to educate patients on how to most effectively use their devices.

Writing in BMJ Open Respiratory Research, corresponding author Lies Lahousse, PhD, of Ghent University, in Belgium, and colleagues, noted that while inhalers are a “cornerstone” of treatment for patients with asthma, chronic obstructive pulmonary disease (COPD), and other lung conditions, success of the treatment depends on patients’ adherence to treatment plans and on their correct usage of the device itself. Neither can be taken for granted, they found.

The investigators wanted to better understand when and why patients have trouble correctly using their inhalers. To find out, they decided to focus on the role of community pharmacies, since community pharmacists have a unique opportunity to help educate patients and identify those who might not be using their devices as suggested.

The authors constructed a cross-sectional study of patients with obstructive lung disease who use 9 community pharmacies in Belgium. A total of 70 patients were included in the study. They had a median age of 64 and 56% were female. Patients were assessed for their use of 122 inhalers (most patients had more than one). Half of patients made “critical errors” in using at least one inhaler, and the study population overall “scored poorly” in their technique.

When surveyed, just 1 in 5 patients (21%) said they had received inhaler instruction from both their physician and their pharmacist, though the majority (71%) said they had received instruction from either the physician or pharmacist. Five patients said they had never been taught the proper technique prior to the start of the study.

Part of the problem, the investigators said, was managing the use of multiple inhalers.

“The strongest determinant of a poor inhaler technique was the use of multiple devices,” Lahousse and colleagues found. Those with multiple devices had an adjusted odds ratio of a critical error of 11.68 (95%  CI, 3.29-41.51).

Patients with 1 device had a critical error rate of 29%, while those with 2 devices had a rate of 75%. All 13 patients who used 3 inhalers had critical errors.

Another factor associated with incorrect usage was asthma-COPD (ACO) overlap. Patients diagnosed with that condition had an adjusted odds ratio of 7.06 (95% CI, 1.15-43.35).

“This finding could be explained by ACO patients being more likely to have comorbidities, which have been associated with poorer inhaler technique,” Lahousse and colleagues wrote. “Furthermore, patients with a lower [quality of life] tended to make more critical errors.”

Patients with asthma alone had better inhaler technique. The investigators said this may be because such patients are more likely to feel a more direct benefit when they properly use their devices.

The investigators measured adherence both by asking patients about their usage and by looking at patient pharmacy dispensing data. Patients with asthma had lower adherence than those with ACO, the investigators found. Current smoking was linked with poor adherence, in this case, overuse. Highly educated younger patients were also more likely to over-use their inhalers, the authors found.

Lahousse and colleagues concluded that the data show many patients who rely on inhalers are not benefiting from the full potential of their devices.

“Given the important role of therapy adherence and a correct inhaler technique in disease control, these findings emphasise the need for patient education and aiming [for] uniformity in the inhaler device,” the authors concluded.

Reference

Vanoverschelde A, van der Wel P, Putman B, Lahousse L. Determinants of poor inhaler technique and poor therapy adherence in obstructive lung diseases: a cross-sectional study in community pharmacies. BMJ Open Respir Res. 2021;8(1):e000823. doi:10.1136/bmjresp-2020-000823