Could interchangeable use of dry powder inhalers affect patients?

General Practitioner Use of Generically Substitutable Inhaler Devices and the Impact of Training on Device Mastery and Maintenance of Correct Inhaler Technique

INTRODUCTION

Generic substitution of inhaler devices is a relatively new phenomenon. The best patient outcomes associated with generic substitution occur when prescribers obtain consent from their patients to prescribe a generic inhaler and also teach their patient how to correctly use the new device. To date, no prospective observational study has assessed the level of training required for general practitioners (GPs) to demonstrate correct inhaler technique using two dry powder inhaler devices delivering fixed-dose combination budesonide/formoterol therapy. This study aims to (1) determine the level of training required for GPs to master and maintain correct IT when using two different dry powder inhalers that are able to be substituted in clinical practice and (2) determine the number and types of errors made by GPs on each device and inhaler device preference at each training visit.

METHOD

A randomized, parallel-group cross-over study design was used to compare the inhaler technique of participants with a Spiromax® placebo device and a Turbuhaler® placebo device. This study consisted of two visits with each participant over a period of 4 ± 1 weeks (visit 1 and visit 2). A total of six levels of assessment and five levels of training were implemented as required. Level 1, no instruction; level 2, following use of written instruction; level 3, following viewing of instructional video; level 4, expert tuition from the researcher; level 5/level 6, repeats of expert tuition from the researcher when required. Participants progressed through each level and stopped at the point at which they demonstrated device mastery. At each level, trained researchers assessed the inhaler technique of the participants. Participants were also surveyed about their previous inhaler use and training.

RESULTS

In total, 228 GPs participated in this study by demonstrating their ability to use a Turbuhaler® and a Spiromax® device. There was no significant difference between the proportion of participants who demonstrated device mastery with the Turbuhaler® compared with the Spiromax® at level 1, (no instruction), (119/228 (52%) versus 131/228 (57%), respectively, n = 228, p = 0.323 (McNemar's test of paired data). All but one participant had demonstrated correct inhaler technique for both devices by level 3(instructional video). There was a significant difference between the proportion of participants who demonstrated maintenance of device mastery with the Turbuhaler® compared with the Spiromax® at visit 2, level 1 (127/177 (72%) versus 151/177 (85%) respectively, p = 0.003; McNemar's test of paired data). All but two participants achieved device mastery by level 3, visit 2. More participants reported previous training with the Turbuhaler® than with Spiromax®.

DISCUSSION

This study demonstrates that GPs are able to equally demonstrate correct use of the Turbuhaler® and Spiromax® devices, even though most had not received training on a Spiromax® device prior to this study. The significance of being able to demonstrate correct technique on these two devices equally has ramifications on practice and supported generic substitution of inhaler devices at the point of prescribing, as the most impactful measure a GP can take to ensure effective use of inhaled medicine is the correct demonstration of inhaler technique.

Difference in resistance to humidity between commonly used dry powder inhalers: an in vitro study

Multi-dose dry powder inhalers (DPIs) are commonly used in asthma and chronic obstructive lung disease (COPD) treatment. A disadvantage is their sensitivity to humidity. In real life, DPIs are periodically exposed to humid conditions, which may affect aerosol characteristics and lung deposition. This study compared DPI aerosol performance after exposure to humidity. Budesonide (BUD) inhalers (Turbuhaler; Novolizer; Easyhaler) and budesonide/formoterol (BUD/FORM) inhalers (Turbuhaler; Spiromax; Easyhaler) were stored in 75% relative humidity (RH) at both ambient temperature and at -0 °C. Delivered dose (DD) and fine-particle dose (FPD) were tested in vitro before and after storage. BUD inhalers: Turbuhaler and Novolizer showed only small decreases (<15%) in FPD in 40 °C/75% RH, whereas FPD for Easyhaler decreased by >60% (P=0.01) after 1.5 months of storage. Easyhaler also decreased significantly after 6 months of storage in ambient/75%RH by 25% and 54% for DD and FPD, respectively, whereas only small decreases were seen for Turbuhaler and Novolizer (<15%). BUD/FORM inhalers: Turbuhaler and Spiromax DD were unchanged in 40 °C/75% RH, whereas Easyhaler showed a small decrease. FPD (budesonide) decreased for Turbuhaler, Spiromax and Easyhaler by 18%, 10% and 68% (all significant), respectively, at 40 °C/75% RH. In ambient/75%RH, DD was unchanged for all inhalers, whereas FPD (budesonide) decreased for Spiromax (7%, P=0.02) and Easyhaler (34%, (P<0.01)). There are significant differences in device performance after exposure to humid conditions. A clinically relevant decrease of more than half FPD was seen for one of the inhalers, a decrease that may affect patients' clinical outcomes. Prescriber and patient knowledge on device attributes are essential to ensure optimal drug delivery to the lungs.

Inhalation errors due to device switch in patients with chronic obstructive pulmonary disease and asthma: critical health and economic issues

BACKGROUND

Different inhalation devices are characterized by different techniques of use. The untrained switching of device in chronic obstructive pulmonary disease (COPD) and asthma patients may be associated with inadequate inhalation technique and, consequently, could lead to a reduction in adherence to treatment and limit control of the disease. The aim of this analysis was to estimate the potential economic impact related to errors in inhalation in patients switching device without adequate training.

METHODS

An Italian real-practice study conducted in patients affected by COPD and asthma has shown an increase in health care resource consumption associated with misuse of inhalers. Particularly, significantly higher rates of hospitalizations, emergency room visits (ER), and pharmacological treatments (steroids and antimicrobials) were observed. In this analysis, those differences in resource consumption were monetized considering the Italian National Health Service (INHS) perspective.

RESULTS

Comparing a hypothetical cohort of 100 COPD patients with at least a critical error in inhalation vs 100 COPD patients without errors in inhalation, a yearly excess of 11.5 hospitalizations, 13 ER visits, 19.5 antimicrobial courses, and 47 corticosteroid courses for the first population were revealed. In the same way, considering 100 asthma patients with at least a critical error in inhalation vs 100 asthma patients without errors in inhalation, the first population is associated with a yearly excess of 19 hospitalizations, 26.5 ER visits, 4.5 antimicrobial courses, and 21.5 corticosteroid courses. These differences in resource consumption could be associated with an increase in health care expenditure for INHS, due to inhalation errors, of €23,444/yr in COPD and €44,104/yr in asthma for the considered cohorts of 100 patients.

CONCLUSION

This evaluation highlights that misuse of inhaler devices, due to inadequate training or nonconsented switch of inhaled medications, is associated with a decrease in disease control and an increase in health care resource consumption and costs.

Budesonide inhaler device switch patterns in an asthma population in Swedish clinical practice (ASSURE)

BACKGROUND

Dry powder inhaler (DPI) device switch in asthma treatment could potentially increase with the entrance of new devices. We examined the switch patterns of budesonide (BUD) DPI analogues available in Sweden.

METHODS

This observational real-life study linked primary healthcare medical records data from the Västra Götaland region to national Swedish registries, and included asthma patients (ICD-10-CM J45) prescribed BUD in a multidose DPI. Index date: first dispense of BUD DPI. Switch date: prescription of another BUD DPI device. Study outcomes (switch vs. non-switch) were exacerbations and prescription of short-acting β2 -agonists. Study period was 1 July 2005 to 31 October 2013.

RESULTS

Overall, 15,169 asthma patients were on treatment with BUD DPI; 1178 (7.35%) switched to another BUD DPI during the study. Pair-wise 1:1 matching of switchers vs. non-switchers resulted in two groups of 463 patients each (mean age 36 years, 55% female patients). A 25% higher exacerbation rate was seen postswitch (0.40 vs. 0.32; p = 0.047). Switchers were 4.5 year younger and had lower medication possession rate than non-switchers. Switch without primary healthcare visit did not differ between groups regarding consultations and exacerbations (no visit 4.96 and 0.90; visit 4.29 and 0.77, respectively). However, patients without primary healthcare visit at switch had significantly more outpatient hospital visits (2.01 vs. 0.81; p < 0.001).

CONCLUSIONS

Considering the low switch rate, asthma patients and physicians in Swedish general practice seem reluctant to switch to another BUD DPI device. Switch, especially without primary healthcare visit, was associated with decreased asthma control resulting in higher exacerbation rate and more outpatient hospital visits.

Asthma and COPD: Interchangeable use of inhalers. A document of Italian Society of Allergy, Asthma and Clinical Immmunology (SIAAIC) & Italian Society of Respiratory Medicine (SIMeR)

Prescription cost-containment measures are increasing in many European countries and, as more inhaler devices become available, there may be pressure to switch patients from reference inhaled medication to cheaper generic inhaled drugs. Indeed, in some countries, such a substitution is mandated by current regulations, and patients who do not accept the substitution have to pay the difference in cost. Generic inhaled drugs are therapeutically equivalent to original branded options but may differ in their formulation and inhalation device. This new situation raises questions about the potential impact of switching from branded to generic inhaled medications in patients with asthma or chronic obstructive pulmonary disease (COPD), with or without their consent, in countries where this is permitted. Acquisition cost savings from a substitution could be offset by costs related to deterioration in asthma control or worsening in COPD outcomes if the patient is unable or unwilling to use the inhaler device properly. Non-adherence to therapy and incorrect inhaler usage are recognised as major factors in uncontrolled asthma and worsening of COPD outcomes. Switching patients to a different inhaler device may exacerbate these problems, particularly in patients who disagree to switch. Where switching is permitted or mandatory, it is crucial that the reason for switching has been properly explained to the patient and adequate instruction for operating correctly the inhaler have clearly been provided.

[The choice of inhalation device: A medical act]

Inhaled treatments are essential for respiratory diseases management, including COPD and asthma. Optimal control of the disease largely depends on patient's compliance and proper use of these treatments. Different types of ready-to-use inhaler devices are available: metered dose inhaler, dry powder inhaler or soft mist inhaler. Each of these devices presents specific characteristics and constraints that have to be evaluated and taken into account before prescription. In order to optimize adherence and treatment efficacy, the choice of inhaler device should depend on the specific needs, abilities and preferences of each patient and a specific education to treatment should be provided. Inhaled treatments, even containing the same drug, have different technical constraints and are thus not easily interchangeable. Their substitution without prior medical consent and without proper training can lead to errors in taking treatment, treatment failures and increased health care consumption. In France, substitution by the pharmacist is not authorized. While patient education must be carried out in collaboration with all health professionals, it is preferable that the choice of inhaler device remains the responsibility of the physician.

Usage of inhalation devices in asthma and chronic obstructive pulmonary disease: a Delphi consensus statement

OBJECTIVES

The study aimed to assess usage of inhalation devices in asthma and chronic obstructive pulmonary disease (COPD).

METHODS

In this two-round Delphi survey, 50 experts in asthma and COPD completed a 13-item, Internet-based, self-administered questionnaire about choice of inhalation device, training and monitoring of inhalation techniques, the interchangeability and the role of costs in the selection of inhalation devices. For each item, the median (central tendency) and interquartile ranges (degree of consensus) were calculated.

RESULTS

Experts considered that the choice of inhalation device was as important as that of active substance (very good consensus) and should be driven by ease of use (good to very good consensus) and teaching (very good consensus). Experts recommended giving oral and visual instructions (good consensus) and systematic monitoring inhalation techniques. Pulmonologists and paramedics have predominantly educational roles (very good consensus). Experts discouraged inhalation device interchangeability (good consensus) and switching for cost reasons (good to very good consensus) without medical consultation (good consensus).

CONCLUSIONS

The results of this survey thus suggested that inhalation devices are as important as active substances and training and monitoring are essential in ensuring effective treatment of asthma and COPD. Inhalation device switching without medical consultation should be avoided.

Switching from branded to generic inhaled medications: potential impact on asthma and COPD

Pressure on healthcare budgets is increasing, while at the same time patent protection for many branded inhaled medications has expired, leading to the development and growing availability of generic inhaled medicines. Generic inhaled drugs are therapeutically equivalent to original branded options but may differ in their formulation and inhalation device. This new situation raises questions about the potential impact of switching from branded to generic drug/inhaler combination products in patients with asthma or COPD, with or without their consent, in countries where this is permitted. Inhalation devices, particularly dry powder inhalers, vary markedly in their design, method of operation and drug delivery to the lungs. Current guidelines stress the importance of training patients how to use their inhalers but offer little or no guidance on how this should be achieved. Non-adherence to therapy and incorrect inhaler usage are recognised as major factors in poorly or uncontrolled asthma and COPD and switching patients to a different inhaler device may exacerbate these problems, particularly in patients who disagree to switch. Where switching is permitted or mandatory, adequate patient instruction and follow-up monitoring should be provided routinely.

Inhaled corticosteroids for asthma: impact of practice level device switching on asthma control

BACKGROUND

As more inhaled corticosteroid (ICS) devices become available, there may be pressure for health-care providers to switch patients with asthma to cheaper inhaler devices. Our objective was to evaluate impact on asthma control of inhaler device switching without an accompanying consultation in general practice.

METHODS

This 2-year retrospective matched cohort study used the UK General Practice Research Database to identify practices where ICS devices were changed without a consultation for > or =5 patients within 3 months. Patients 6-65 years of age from these practices whose ICS device was switched were individually matched with patients using the same ICS device who were not switched. Asthma control over 12 months after the switch was assessed using a composite measure including short-acting beta-agonist and oral corticosteroid use, hospitalizations, and subsequent changes to therapy.

RESULTS

A total of 824 patients from 55 practices had a device switch and could be matched. Over half (53%) of device switches were from dry powder to metered-dose inhalers. Fewer patients in switched than matched cohort experienced successful treatment based on the composite measure (20% vs. 34%) and more experienced unsuccessful treatment (51% vs. 38%). After adjusting for possible baseline confounding factors, the odds ratio for treatment success in the switched cohort compared with controls was 0.29 (95% confidence interval [CI], 0.19 to 0.44; p < 0.001) and for unsuccessful treatment was 1.92 (95% CI, 1.47 to 2.56; p < 0.001).

CONCLUSION

Switching ICS devices without a consultation was associated with worsened asthma control and is therefore inadvisable.

Use of dry powder inhalers in COPD

INTRODUCTION

This was a study of 30 chronic obstructive pulmonary disease (COPD) patients to assess the ease of use and preference of four dry powder inhalers -- accuhaler, aerolizer, handihaler, turbohaler -- the accuhaler and turbohaler are multidose devices, whereas the aerolizer and handihaler are single dose devices.

METHOD

None of the subjects had previous experience of dry powder inhalers. The correct technique for each inhaler was divided into 12 steps including one critical step that if not performed would result in no drug delivery. Subjects were shown the correct technique for each inhaler in a random order and were assessed immediately and 1 h later. Each subject was asked to rank the four devices for preference and ease of use, as well as to assess how comfortable it felt to inhale through the device using a visual analogue scale.

RESULTS

The numbers of perfect scores were not significantly different between devices, but the number of fatal errors that would result in no drug delivery was significantly more common in single dose devices (p < 0.01). There were significant differences in the rankings of each device (Friedman test, p < 0.005) with the turbohaler being ranked first most often and the handihaler last. The turbohaler scored highest for comfort of inhalation and the accuhaler lowest, but differences were small.

CONCLUSIONS

In COPD patients starting on dry powder inhalers, multidose devices appear to be preferred, have fewer problems and are easier to use effectively.

Survey of pharmacists' attitudes towards interchangeable use of dry powder inhalers

BACKGROUND

It is a common cost-containment practice in some countries to dispense a cheaper, generic version of a prescribed medication. This presents few problems for most medications. However, dry powder inhalers used in asthma and COPD vary markedly in design and method of operation, so generic substitution may not be acceptable to patients or healthcare professionals. Patients dispensed an unfamiliar device in which they have received no training, risk poor inhalation technique with the potential for inadequate dosing and loss of disease control.

OBJECTIVE

To assess the views of pharmacists towards interchangeable use of dry powder inhalers.

SETTING

Community pharmacists in Australia, Canada, France, Germany, and the UK.

METHOD

Following exploration of the key issues with international opinion leaders in respiratory management, a structured web questionnaire was developed for use in computer assisted web interviews. Fieldwork was carried out in March and April 2005.

MAIN OUTCOME MEASURE

Responses to the web questionnaire were analysed by percentage of respondents or by mean or median score, as appropriate to the question.

RESULTS

A total of 254 pharmacists were included in the study. Just 6% of pharmacists considered that dry powder inhalers are interchangeable, with a high level of concern shown about interchangeable use (median score of 6 on a scale of 1, not at all concerned, to 7, extremely concerned). Patient confusion was the main concern, expressed by 77% of respondents. Pharmacists also envisaged substitution having an adverse impact on pharmacy stock levels (72%), patient device handling (70%), pharmacist workload (63%), patient compliance (56%) and outcomes for the patient (51%), with pharmacists in Germany having a particularly negative view and those in France generally the most positive. Despite the generally negative view of pharmacists about interchangeable use of dry powder inhalers, overall only 22% would contact the prescribing physician often/very often for approval of the substitution.

CONCLUSION

The study showed that only a small minority of pharmacists believe that dry powder inhalers can be used interchangeably, with the majority concerned about generic substitution of these products. Pharmacists in Germany were particularly negative about the interchangeable use of dry powder inhalers.

The way forward: dry powder inhalers should only be switched with physician agreement and patient training

Assessment of pharmaceutical performance, patient behaviour and clinical outcomes shows that dry powder inhalers cannot be used interchangeably, even if they contain the same active chemical entity. Consequently, there should be no switching of device without the involvement of the physician and appropriate training for the patient.