Factors Accounting for Incorrect Inhaler Technique in COPD

22 Nov, 21

Introduction

Correct inhaler technique is crucial in the clinical management of chronic obstructive pulmonary disease (COPD). Incorrect inhaler technique leads to inadequate amount of drug and hence a poor clinical response. There are different inhalation devices and not all are appropriate for all the patients due to differences in their performance. There is a discrepancy about determinants of incorrect inhaler technique among COPD patients in the existing literature.

Aim

This study estimates the prevalence and evaluates the possible determinants of incorrect inhaler technique in COPD subjects with common inhalers.

Method

Study Design

Randomized, open-label, non-drug interventional crossover study

Patient Profile

Adults aged ≥40 years with confirmed diagnosis of COPD

Treatment Strategy

The study recruited 180 COPD subjects.
A total of 10 placebo inhalers were evaluated that included breath-actuated dry powder inhalers (DPIs), non-breath-actuated pressurized metered dose inhaler (pMDI) and soft mist inhalers (SMI).
The patients were randomized to begin with one inhaler without receiving any verbal or demonstrative instructions.
Then the patients were crossed over to other inhalers in random order.
Inhaler technique was evaluated, and the critical and non-critical errors were assessed.
In case of an error, the whole correct inhaler technique was demonstrated, and the number of counselling attempts needed to achieve a completely correct technique was recorded.
Patient past-experience to inhalers, demographics and clinical variables were recorded.

End Points

Primary End Points

Mean % of total and critical errors
% Patients with each error with each inhaler

Secondary End Points

Number of counselling attempts needed to reach a completely correct inhaler technique
Baseline % of total errors
Relative determinants of incorrect inhaler technique

Results

The prevalence of incorrect inhaler techniques was significant ranging from 80% to 100%; p < 0.001.
The most commonly reported device non-dependent errors were
- No breath-hold after dose inhalation
- No exhalation before dose inhalation.
Incorrect inhaler technique was more prevalent among females and elderly subjects (>60 years old) than males and younger subjects.
Older subjects performed better with pMDI.
Significant determinants of incorrect inhaler technique were past-experience (OR = 14.639 at P < .001) and inhaler-type followed by gender (OR = 0.310 at P < .001), age category (OR = 0.307 at P < .001) and GOLD group (OR = 2.289 at P =. 005).

Conclusions

The prevalence of incorrect inhaler techniques is remarkably high among COPD subjects.
The most significant determinants of incorrect inhaler technique were lack of past-experience, certain inhaler types, female gender, older age and lower GOLD group.

Int J Clin Pract. 2021 Jun;75(6): e14073. Doi: 10.1111/ijcp.14073.