Objectives The aim of this study was to examine the effect of metered dose inhaler (MDI) counselling on the inhalation technique and pulmonary function test scores of patients with asthma.
Methods 491 subjects with asthma (281 female) attending the Beni Suef University hospital outpatient clinics were enrolled during a 2-year period. Their mean (SD) age was 42.1 (17.1) years. Their MDI inhalation technique was checked and the number of mistakes was noted and corrected at the first visit and at each of two following monthly visits (three visits in total). Their peak expiratory flow and forced expiratory volume in 1 s (FEV1) as a percentage of the forced vital capacity were checked at each visit.
Results Most MDIs contained salbutamol, although some patients were using MDIs containing beclomethasone or a combination of beclomethasone and salbutamol. The mean number of mistakes observed decreased significantly (p<0.001) as the number of visits increased, especially in the children's group. The most common repeated mistake was failure to maintain a slow inhalation rate until the lungs were full. There was a significant improvement (p<0.001) in pulmonary function test scores after counselling in all age groups, particularly in those aged >60 years.
Conclusions MDI counselling should be frequently repeated to improve and maintain the recommended MDI inhalation technique and possibly improve patients’ pulmonary function tests scores.
- Metered dose inhaler
- number of mistakes
Statistics from Altmetric.com
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.
The inhaled route remains important for the treatment of bronchial diseases. However, inhalers differ in their efficiency of drug delivery to the lower respiratory tract, depending on the form of the device, its internal resistance, medication formulation, particle size, velocity of the produced aerosol plume, and ease with which patients can use the device.1–5 Metered dose inhalers (MDI) are effective and easily used when patients are away from home. They are the gold standard treatment for reversible airflow obstruction since they provide reliable, reproducible and effortless dosing.6 ,7
Asthma remains poorly controlled partly because patients receive incomplete benefit from their inhaled medication if they are unable to use their inhalers correctly.8–12 A poor inhalation technique can result in decreased drug deposition in the lungs, increased oropharyngeal deposition and decreased asthma stability.13 ,14
Adherence to inhaled therapy in asthma is influenced by several factors, including patient understanding of the need for therapy, daily dosing frequency and acceptance of the inhaler device.15 Continuing education of patients with asthma was found to enhance the probability of long-term control and is often very important for effective management of different airflow limitations.16–18 It also may improve the pulmonary function scores, quality of life and morbidity of patients with asthma and chronic obstructive pulmonary disease (COPD).18
It was shown previously that dividing the MDI inhalation technique into separate steps may assist patients in improving their technique.16 This makes counselling more effective and enables healthcare providers to identify errors in technique.16
Hence, the aim of this work was to study the effect on inhalation technique and lung function test scores of counselling patients using their own MDIs.
Subjects and methods
Subjects above 10 years of age who were able to perform the pulmonary function test correctly and to respond to counselling were recruited from the Beni Suef University hospital outpatient clinics over a 2-year period.19 Ethics approval was obtained from Beni Suef University for the study and all subjects gave signed informed consent. All patients were evaluated on admission when a detailed history was taken which included demographic data (name, age and gender) and medical history (eg, family history of obstructive lung disease, symptoms, precipitating factors and diagnosis).
Each patient attended three visits 1 month apart. At each visit, subjects were asked to show the investigator how they used their MDI. The MDI inhalation technique was divided into separate steps16 and the investigator noted and corrected any mistakes.
MDI inhalation technique
Step 1. Remove the protective cap from the MDI mouthpiece.
Step 2. Shake the MDI.
Step 3. Breathe out as far as comfortable.
Step 4. Place the MDI mouthpiece between the teeth and seal with the lips.
Step 5. Ensure your tongue does not obstruct the mouthpiece.
Step 6. Depress the inhaler to release the dose at the start of inhalation.
Step 7. Maintain a slow inhalation rate until the lungs are full.
Step 8. Remove the MDI from the mouth and hold your breath for 5–10 s.
Step 9. If more than one dose is being taken, wait about 30 s before taking the next dose.
Step 10. Rinse the mouth and if possible brush the teeth after dosing.
Step 11. Replace the cap on the MDI.
At every visit, before counselling began, each subject was asked to perform a pulmonary function test using a handheld spirometer (One-Flow FVC Kit, Clement Clarke, UK) to measure lung function parameters. The outcome data were peak expiratory flow (PEF) in L/min and forced expiratory volume in 1 s (FEV1) as a percentage of the forced vital capacity (FVC). The investigator showed the correct technique to any patient having trouble correctly performing the test.
Subjects with asthma able to perform the pulmonary function test correctly, treated with an MDI and over 10 years of age were included in the study.
Patients were excluded if they had any mental disease affecting their learning ability, were unable to perform the pulmonaryfunction test correctly, or were being treated in an intensive care unit.
Analysis was carried out using the Friedman test followed by the Wilcoxon test for the comparison between the main variables and within-group comparison of PEF and FEV1/FVC percentage and for mean number of mistakes at each visit.
The Cochran test followed by the McNemar test was used to compare the total number of mistakes in each step at each visit.Analysis of the effect of age categories on MDI results (PEF and FEV1/FVC percentage and mean number of mistakes of each visit) was performed using two-way ANOVA analysis at p<0.05 followed by post hoc ANOVA using the Tukey system.
A total of 491(281 female) subjects with asthma (mean (SD, range) age 42.1 (17.1, 10–78) years) completed the study. Patients were divided into age groups due to the wide variation in their ages and to investigate if counselling was affected by age. The results of the whole group together and of each of four age groups were studied.
There were 81 (54 females) subjects in group 1 (GP1; <18 years old), 135 (85 females) in group 2 (GP2; >18–40 years old), 207 (112 females) in group 3 (GP3; >40–60 years old) and 68 (30 females) in group 4 (GP4, >60 years old).
Most of the subjects (400 (230 female) patients) used MDIs containing salbutamol, however some used MDIs containing beclomethasone dipropionate (50 (27 females) patients) or a combination of beclomethasone and salbutamol (41 (24 females) patients). This did not have any significant affect on any of the tested parameters. There were no significant differences in any tested parameter between male and females patients in the total sample or in any age group. The mean (SD) values for PEF, FEV1/FVC% and number of mistakes are presented in table 1 and figure 1. There was no significant difference between the four age groups at any visit regarding PEF. However, FEV1/FVC% in GP4 was significantly lower than in GP2 and GP3 at the first and the third visits (p=0.001). There were also significantly more mistakes in GP1 compared to GP3 (p=0.048) at visits 1 and 2 but no significant difference at visit 3. The number of mistakes in each step at the three visits are shown in table 2 and figure 2. There were no mistakes at all in some steps, while mistakes in others improved with counselling as shown in table 2 and figure 2. There was a significant (p<0.001) decrease in the number of mistakes at the second visit compared to the first, followed by another significant (p<0.001) decrease in the number of mistakes at the third visit compared to the first and second. The only non-significant difference between two visits was in step 7 ‘Maintain a slow inhalation rate until the lungs are full’ between the first and second visits, with a high number of mistakes at the second visit. The percentage of correct steps for the four age categories at each visit is presented in figure 3. All steps had comparable results in the four age categories except for step 7 as shown in figure 3.
Drug deposition and subsequent treatment effectiveness are highly dependent on inhalation technique, which is incorrect in many patients with asthma.20 It was previously shown that increasing patient knowledge about self-management through counselling can improve adherence to medication.21 ,22
The difficulties that patients with asthma experience when using their MDIs were investigated in this study. Similarly to previous studies,13 ,17 ,23 the results showed that most patients using MDIs did not perform the correct inhalation technique at the first visit, but significantly improved at the second (p<0.001) with further improvement at the third visit (p<0.001) in all age groups and overall. Thus, repetition of the instructions was significantly correlated with the correct inhalation technique (p<0.001).19
The results show that step 7 was the most difficult because it was very hard to teach patients how to maintain a slow inhalation rate until the lungs were full.24 ,25 This was shown by the very slow improvement in the overall results for step 7 and the inconsistent results in the four age groups. Thus, extra instruction on step 7 should be offered at every opportunity, as patients may forget or be uncertain of how to maintain a slow inhalation rate.
The number of correct steps improved at each visit following counselling in all age groups. Even in step 7 there was a significant improvement at the third visit.
It was previously shown that the most common mistakes were in steps 2, 7, 8 and sometimes 10.25 However, our results show that steps 2 (‘Shake the MDI’), 8 (‘Remove the MDI from the mouth and hold your breath for 5–10 s’) and 10 (‘Rinse the mouth and if possible brush the teeth after dosing’) are much easier to remember when taught well compared to step 7. Therefore, counselling must be repeated regularly and at every possible opportunity. Training devices that could be used include the 2Tone Trainer device or the In-Check Dial to help patients obtain the best inhalation rate when using an MDI.24 The patient information leaflet provided with the 2Tone Trainer encourages patients to practice using the device in the same way that they would use their MDI.24 There are also various educational tools which can be used to counsel patients including videos, web-based platforms and tele-counselling.20
A decrease in the mean number of mistakes for step 4 at the three visits was found but was not significant for GP1 (children) or GP4 (older patients), perhaps because those two groups found it difficult to remember to place the MDI mouthpiece between the teeth and not only between the lips.
There were no mistakes at any visit in some steps, such as step 1 (‘Remove the protective cap from the MDI mouthpiece’), step 5 (‘Ensure your tongue does not obstruct the mouthpiece’), step 6 (‘Depress the inhaler to release the dose at the start of inhalation’) and step 11 (‘Replace the cap on the MDI’). However, a few errors in step 1 (‘Remove the protective cap from the MDI mouthpiece’) were previously found.13
GP1 (children) made more errors with inhalers if they lacked reassessment and reinforcement of their MDI inhalation technique as most patients in this group have little previous experience. However, most adult MDI users had long experience of using MDIs. This was reflected in the significantly higher mean number of mistakes in GP1 (children) at the first and second visits compared to the other (adult) groups, followed by no significant difference at the third visit. Therefore, the ability to correctly use an inhaler could be positively correlated with age and experience. However, two previous studies showed that there was no effect of age, education or device used,23 ,25 but this result may be because the adults studied were newly diagnosed patients with less MDI experience.
Also, table 1 shows that the change in the mean number of mistakes between the first and third visits was highest in GP1: when taught well, younger patients tend to perform inhalation, breath holding and exhalation steps better than older patients due to their superior learning ability and memory.22
At the first visit, GP3 (>40–60 years old) had the least number of mistakes as shown in table 1 and figure 3, possibly because most members of this category had long experience of using MDI inhalers. However, GP3 was also the group showing least improvement, perhaps because they believed that they were already using the correct inhalation technique.
The lung function tests of patients improved as shown by the better PEF and FEV1/FVC% results, although this improvement lagged behind the improvement in the number of mistakes.
A significant improvement in the FEV1/FVC% results was not seen between the first and second visits for all patients together or for each age group individually, but was found at the third visit (p<0.001). Similarly, patients with asthma receiving education showed a mean increase in FEV1 and FVC values over the final month, which was statistically significant.18 PEF improved gradually from the first to the third visit, as show by the p values in table 1, except for GP2 (>18–40 years old), which did not show a significant difference. GP2 had the highest PEF of all groups at the first visit and but similar PEF values at the second and third visits.
A clinically significant improvement in the pulmonary function test was previously shown in counselled patients.17 ,26 This result supports the recommendation of counselling at every opportunity.
Counselling showed a beneficial effect on lung function tests in all groups, especially GP4 patients (>60 years old), who may need continuous counselling and follow-up due to their memory problems as a result of cognitive decline with aging, and poor vision leading to inhaler misuse.22 ,27 Also, many GP4 patients had osteoarthritis which might make MDI use difficult,16 and so they may need use the MDI with a spacer device even in the initial stages of disease.16
In the present study, counselling improved the mean number of mistakes and lung function tests progressively in all age groups. Therefore, counselling should be repeated at every possible opportunity as recommended by asthma and COPD guidelines.28 ,29 Most patients’ knowledge regarding disease, risk factors, management and precautions improved in response to counselling.30 Hence, proper training and regular checking of inhalation technique remain critical to optimise treatment effectiveness.18 ,20 ,25 ,31
Without counselling, the inhaler may be used incorrectly, which can cause low drug deposition in the lungs. The patient must be carefully taught how to carry out those MDI inhalation steps that are liable to serious error, for example, maintaining slow inhalation. Hence, to obtain the most benefit from counselling, we recommend that the inhalation technique should be checked and reinforced at regular intervals especially in older patients who might have greater difficulty using the MDI properly. Continuous counselling could improve the quality of life of the patient by improving their lung function.
What is already known on this subject
Inability to use their inhalers correctly results in patients receiving incomplete benefit from their inhaled medication and contributes to poor control of asthma.
Patient education can increase awareness and improve adherence to drug schedules.
What this study adds
Counselling patients using their own metered dose inhalers improved their inhalation technique and lung function test scores.
Contributors MOE: patient recruitment, data entry, and writing the manuscript; MEA: concept, planning of study design, statistics, and writing the manuscript; RSE: concept, study design, and writing the manuscript.
Competing interests None.
Ethics approval Beni Suef University Faculty of Medicine approved this study (FMBSU REC FWA#: FWA00015574).
Provenance and peer review Not commissioned; externally peer reviewed.