Formoterol

Real-life association between inhaler technique, patient preference and asthma control in patients with uncontrolled asthma switched to budesonide/ formoterol DuoResp® Spiromax® combination

Nicolas Roche, MD, PhDa, Bernard Aguilaniu, MD, PhDb, Simon Paternotte, MScc and Nathalie Dallery, PhDd

ABSTRACT

Objective: In asthma, treatment effectiveness is strongly influenced by the quality of inhaler use. New devices such as Spiromax® have been specifically developed to improve ease of use. It is crucial to determine whether switching to such a device improves inhaler technique and clinical outcomes, and to identify factors associated with handling errors.
Methods: This observational study assessed inhaler device handling errors in 1435 asthma patients recruited via 135 participating physicians in France, before and after switching therapy from the Symbicort Turbuhaler® or Seretide® Diskus® to DuoResp® Spiromax®. Patients received training in the use of their new device at baseline and were re-assessed after three months.
Results: After three months of use, 67% of patients were using the DuoResp® Spiromax® with no handling errors, and 88% with no critical errors. The presence of comorbidities was associated with handling errors overall. Concurrent illness potentially affecting device handling and previous training were associated with critical device handling errors. Most patients (85.4%) preferred DuoResp® Spiromax® over their previous device. Levels of inadequately controlled or uncontrolled asthma were reduced from baseline among patients using DuoResp® Spiromax® (8.6% versus 64.6%), and were higher in patients with critical handling errors.
Conclusions: Effective patient education, correct inhaler technique, treatment adherence and devices associated with high patient satisfaction are interrelated factors key to the successful delivery of inhaled asthma therapy. Inhaler technique and patient device satisfaction should be routinely assessed in treated patients with uncontrolled asthma.

KEYWORDS
Patient preference; inhaler; technique; DuoResp® Spiromax®; asthma; budesonide; fomoterol; Symbicort; Seretide; adherence

Introduction

Correct inhaler technique is recognized as crucial in the management of asthma (1). However, despite improve- ments in drug delivery/ease of use, many patients with asthma do not use their inhaler devices correctly (2,3). Inadequate inhaler technique results in poor disease con- trol (4–9). Dry-powder inhalers (DPIs) overcome coordi- nation difficulties, which are common with metered-dose inhalers (MDIs), but studies have shown that mishandling of DPIs is also common in real life (3,10–13). Repetitive device training has been shown to increase the frequency of correct inhaler use (13), and while poor device handling has been associated with a shorter duration of disease and inhaler use, inhaler errors are also associated with longer duration of therapy as patients become overconfident with using their device (13).
The Spiromax® device is a DPI designed to allow the administration of inhaled medications with the lowest possible number of steps (i.e. open, inhale, close). The DuoResp® Spiromax® DPI has been available in France since January 2016 (14) and contains a fixed-dose combi- nation budesonide, an inhaled corticosteroid (ICS), and formoterol, a long‐acting β2 adrenergic receptor agonist (LABA). In a recent 12-week, randomized study (Easy Low Instruction Over Time [ELIOT]), a significantly greater proportion of patients with moderate-to-severe asthma using DuoResp® Spiromax® versus Symbicort Turbuhaler® achieved device mastery (15).
Here we report the findings of a national, observational, multicenter real-life study in France of a large sample of patients who were switching asthma therapy from Symbicort® Turbuhaler® or Seretide® Diskus® to DuoResp® Spiromax®. The objectives of the study were to (1) evaluate the inhalation technique of patients using DuoResp® Spiromax®, (2) estimate the relationship between critical errors and disease control, and identify factors associated with mishandling. Understanding common errors could help improve the train- ing of healthcare professionals (HCPs) and patients.

Methods

Study design and patients

This was an observational, prospective, longitudinal, national and multi-center cohort study conducted in France, in real-life clinical practice and patient care set- tings. Patients were treated upon the initiative of partici- pating physicians alone. Patients with uncontrolled asthma in whom physicians decided to switch treatment from Symbicort® Turbuhaler® or Seretide® Diskus® to DuoResp® Spiromax® as part of their routine asthma management were included and fol- lowed up for 3 months (±3 days). The baseline visit (V1) was designated as the appointment at which DuoResp® Spiromax® was prescribed. The end-of-study visit (V2) was the appointment at which treatment was followed up about 3 months after its prescription.

Patient recruitment

All physicians involved in asthma treatment who were listed in files of French general practitioners (GPs) and respiratory specialists supplied by an external indepen- dent vendor were contacted by post and invited to take part in the study. Follow-up telephone calls were made in cases of non-response, non-receipt or noncompliance of the necessary documents. Those who responded pos- itively to the invitations to participate were recruited. During the recruitment period, each participating phy- sician routinely requested the participation of patients aged over 18 years with uncontrolled asthma (asthma control test [ACT] score <20 [poor control] (16,17)) despite treatment for ≥3 months with fixed-dose combi- nation DPI, in whom they decided to start treatment with DuoResp® Spiromax® as part of their asthma manage- ment. Patients were informed about the study by means of an information leaflet and asked to provide verbal consent. Each participating physician was asked to enroll a maximum of 20 eligible patients seen in clinical prac- tice. Exclusion criteria included contraindication to treat- ment with DuoResp® Spiromax® and pregnancy or breastfeeding. The study was conducted in accordance with the ethical principles described in the Declaration of Helsinki, Good Epidemiological Practice and French regulatory requirements as of the time of study initiation (Act No. 78–17 of 6 January 1978 on Data Processing, Data Files and Individual Liberties, amended by Act No. 2004–801 of 6 August 2004). The Commission Nationale de l’In- formatique et des Libertés (CNIL) authorization number was DR-2016–407. Endpoints and assessments The primary endpoint for the study was percentage of patients using DuoResp® Spiromax® with no handling errors 3 months after the first prescription. Common inhaler technique errors were assessed by an expert panel and defined as critical or non-critical. Secondary endpoints included: • Exposure to treatment: Dose and administration regimen prescribed, training received, duration of treatment and number of doses taken, discontin- uation from treatment, concomitant treatments. • Treatment adherence: Ratio between the number of doses actually taken (as assessed by examination of dose counters) and the number of prescribed doses. • Incorrect use of inhalation devices: Number and percentage of each handling error categorized by type of inhaler (patients were assessed with their current device at study initiation). • Predictive factors related to the use of DuoResp® Spiromax®: Characteristics of patients using DuoResp® Spiromax® with no handling errors and with at least one handling error 3 months after the first prescription. • Patient satisfaction and preference: Satisfaction scores (performance, functionality and overall satisfaction) for each inhaler and preference score (Patient Satisfaction and Preference Questionnaire [PASAPQ]) (18). • Asthma control (ACT score) after 3 months of treat- ment with DuoResp® Spiromax®, according to the use of DuoResp® Spiromax® (with or without han- dling errors) and according to treatment adherence. • Safety: Adverse events (AEs), deaths, serious adverse events (SAEs) and other significant events. Patient sociodemographic and disease state data and other assessments were collected during the two study visits (see Supplementary Methods). Physician and patient data were recorded by participating physicians in a custom-designed electronic case report form. Statistical analysis Sample size For the purpose of sample size estimation, the expected per- centage of patients not making any technical errors was esti- mated at 50%, and the expected age distribution of patients was expected to be: ≤35years, 30%; 35–65years, 40%; ≥65 years, 30% (7). To enable 5% accuracy to be achieved in the smaller subgroups, a total sample of 1283 patients would be required. Taking into consideration an estimated rate of inadequate data for the primary endpoints of 10%, the required sample size was estimated as 1430 patients. Study populations The primary analysis population comprised all patients enrolled in the study who met the inclusion criteria and attended a follow-up/end-of-study visit. Age subgroups were defined a priori for the analysis of the primary and secondary endpoints: patients aged ≤35years, 35–65years, and ≥65years. The safety population comprised all patients enrolled in the study and receiving at least one dose of DuoResp® Spiromax®. Statistical methods Primary and secondary endpoints were evaluated using descriptive statistics as appropriate for the variable type. Exploratory statistical tests to investigate the data distri- butions of quantitative variables and the patient distribu- tions for qualitative variables are summarized in the Supplementary Appendix. All statistical analyses were performed by ICTA PM using SAS® software (version 9.2 – SAS Institute, North Carolina, USA). Results Participating physicians Overall, 12 138 physicians were contacted. Of these, 577 responded to contact by study investigators, of whom 384 agreed to participate, 235 were registered as study partic- ipants and 135 enrolled at least one patient (active physi- cians; see Supplementary Figure S1). Active physicians saw a mean of 33.34 (±24.67) asthma patients per month. Patient demographics and medical history Between 22 November 2016 and 30 October 2017, 1435 patients were enrolled in the study, of which 1433 satisfied the inclusion and exclusion criteria defined by the study protocol and constitute the safety population. The primary analysis population included 1398 patients who met the inclusion/non-inclusion criteria and attended the follow-up visit. Mean duration of follow-up in the primary analysis population was 95 ± 13 days, and sociodemo- graphic data and medical history are presented in Table 1, with data according to specialty of recruiting physician in Supplementary Table S1. The mean age of patients was 52.8 years, and more than one quarter were aged at least 65 years. Just over half (54%) of participants were women. Nearly two thirds of patients (65%) had an ACT score <16, and 49% had already had at least one severe asthma exacerbation. Of the 1398 patients in the primary analysis population, 692 had previously been using Symbicort Turbuhaler® and 706 had been using Seretide® Diskus®. The most common reason for change of inhaler was inadequate asthma control (65.2% of patients) Exposure to treatment Initial prescription and training The 60-dose inhaler (320 µg budesonide and 9 µg formo- terol per dose) was prescribed in 57.3% of cases and the 120-dose inhaler (160 µg budesonide and 4.5 µg formoterol per dose) in the remaining 42.7%. Most patients (n = 1007; 72.2%) received a prescription for continuous maintenance treatment; 331 (23.7%) patients received a prescription for maintenance and reliever treatment scheme; 57 (4.1%) received an on-demand prescription only, with no recom- mendation regarding the number of daily inhalations. The median number of recommended inhalations was two inha- lations per day, regardless of the prescribed dosage and patient age. Overall, 1267 (90.8%) patients received training: for trained patients a demonstration device was involved in 93.8% of cases (and trialed by the patient in 55.6% of cases), user instructions were read with the patient in 26.1% of cases and a video was shown in 4.0% of cases. Dosing during follow-up In total, 1370 patients (98%) were still being treated with DuoResp® Spiromax® at the follow-up visit. Two percent of patients (28 patients) discontinued treatment during the follow-up period. The most common reason for dis- continuation of treatment was patient decision (n = 19; 67.9% overall), followed by AE (n = 5; 17.9%) and lack of efficacy (n = 4; 14.3%). Primary endpoint analysis Of the 1398 patients in the primary analysis population, 925 (66.5%) were using their DuoResp® Spiromax® inha- lation device with no handling errors at the 3-month follow-up visit (Table 2). The proportion of patients using their device with no handling errors was smaller among patients aged ≥65 years (60.3%) compared with the other sub-groups (68.6% and 68.9% for patients aged ≤35 and 35–65 years, respectively), although the difference was not statistically significant. A breakdown of the number and percentage of patients making the individual errors with DuoResp® Spiromax® is provided by age group in Table 3. Summaries of the handling errors made among patients using Symbicort Turbuhaler® and Seretide® Diskus® are provided in Supplementary Tables S2–5. Factors related to device handling errors Multivariate analysis of associations between selected patient factors and the occurrence of no handling errors with the DuoResp® Spiromax® is shown in Figure 1, with a similar analysis for critical handling errors in Supplementary Figure S2. Only the presence of an illness that could affect device handling or other comorbidity was found to signifi- cantly increase the likelihood of handling errors overall. Interestingly, critical errors were associated both with ill- nesses that could affect device handling and with having received training with the device rather than no training or non-device training (e.g. reading the patient leaflet only). Asthma control The impact of using DuoResp® Spiromax® on asthma con- trol was evaluated by describing the level of asthma control at the follow-up visit with or without critical device han- dling errors. After around 3 months of DuoResp® Spiromax® use, 8.6% of patients had inadequately con- trolled or uncontrolled asthma (ACT score <16) versus 64.6% at the start of treatment. Of the patients who used DuoResp® Spiromax® with no critical handling errors (87.5%; n = 1217), 8.1% had inad- equately controlled or uncontrolled asthma and 21.2% had partially controlled asthma (ACT 16–19) at the follow-up visit. By contrast, of those who made ≥1 critical handling error when using Spiromax (n = 173), 12.1% had uncon- trolled or inadequately controlled asthma and 38.7% had partially controlled asthma. Asthma control data for patients using Symbicort Turbuhaler® or Seretide® Diskus® are presented in Supplementary Table S6 and S7. For patients presenting with poorly controlled asthma at the follow-up visit (n = 120), there was no relationship between the occurrence of critical handling errors and level of asthma control. Treatment adherence Amongst the 1286 patients who received a prescription for continuous maintenance with or without an on-demand component, 74% were determined to have an adherence level of ≥80% of prescribed doses based on examination of dose counters. Patient satisfaction and preference The satisfaction and preference of patients regarding their inhalers was evaluated using the PASAPQ questionnaire (Figure 2). The majority of patients (85.4%) indicated a preference for DuoResp® Spiromax® over their previous inhaler, 11.5% indicated that they had no preference and 3.2% indicated a preference for their old inhaler; no signif- icant differences were observed according to age sub-groups. Incorrect use of inhalation device by study timepoint and type of inhaler At baseline, patients had a median of three handling errors each, including one critical error, and there was a higher frequency of handling errors for patients aged 65 and over. The percentages of patients who made no error and no critical error with the DuoResp® Spiromax® at follow-up (3 months after medication switch and device training) are shown in Figure 3. Among the 1390 patients using the DuoResp® Spiromax® inhaler at the follow-up visit (91% having received proper education at baseline), 925 (66.5%) made no errors and 1217 (87.6%) made no critical errors. At the follow-up visit, no significant dif- ferences were observed according to age sub-groups for the frequency of critical errors. It was notable that 68.2% of patients who preferred the DuoResp® Spiromax® inhaler did not make any handling errors when using their inhaler during the follow-up visit, compared with 48.8% of patients who preferred their old inhaler. Similarly, 11.2% of patients who preferred DuoResp® Spiromax® made at least one critical error compared with 28.0% of patients who preferred their old inhaler. Safety 1433 patients who enrolled in the study who received at least one dose of DuoResp® Spiromax®, were included in the safety analysis (Supplementary Table S8). Of these, 26 (1.8%) experienced ≥1 AE, and 9 (0.6%) experienced an AE deemed possibly related to DuoResp® Spiromax®. Two patients (0.1%) experienced at least one SAE, neither of which was deemed related to DuoResp® Spiromax®. Discussion This observational, prospective, multicenter study, involv- ing 135 French physicians and respiratory specialists, was conducted in adult patients with inadequately controlled asthma (ACT score <20), treated with a fixed ICS/LABA combination in dry-powder form for inhalation for at least 3 months and starting treatment with DuoResp® Spiromax®. After 3 months of use, 67% of patients were using the inhaler with no handling errors and 88% with no critical errors. The patients who were using their inhaler without critical errors had well-controlled asthma (ACT >19) in 71% of cases, compared with 49% of patients who were making at least one critical handling error.
The multivariate analysis did not identify any clear pre- dictive factors related to the incorrect handling of the device after 3 months of use, except the presence of comor- bidities (obesity, diabetes, gastro-esophageal reflux, cerebrovascular disease or arteriopathy). The presence of an illness with potential to affect the handling of inhalation devices and the type of training received appeared to have an impact on the occurrence of critical handling errors; however the imbalance in the numbers of device-trained patients and those who did not receive training (1188 ver- sus 128 patients, respectively), indicates that this result should be interpreted with caution.
As in our study, various age-related comorbidities (e.g. obesity, heart disease and cognitive impairment) have been shown to be associated with device handling errors (9). In the present study, patient age, sex and level of education did not influence the frequency of device handling errors. These observations are in line with current literature, although there is considerable heterogeneity across pub- lished studies with respect to definitions of critical errors, checklists used to teach and assess correct inhaler tech- nique, patient populations studied, and study method- ology (9).
The rate of incorrect use of DuoResp® Spiromax® (34% of patients committed at least one error and 12% of patients committed one critical error) was far lower than that pre- viously reported with other DPIs (7), and with the patients’ prior Symbicort Turbuhaler® or Seretide Diskus® at the time patients were enrolled in the study. However, this observation is confounded by uncertainty regarding the amount and recency of patient education for the use of their previous device. Satisfaction scores for DuoResp® Spiromax® were higher than for Symbicort Turbuhaler® and Seretide Diskus®, and 85% of patients preferred using DuoResp® Spiromax® rather than their prior inhaler. This observation may be partially influenced by the novelty of the DuoResp® Spiromax® to the patient, but the consider- able association between device preference, treatment adherence and asthma control underlines the importance of confirming not only that patients have good inhaler technique, but also that they like their inhaler device, espe- cially for patients with uncontrolled asthma. Inhaler device satisfaction has been shown to have a positive effect on adherence and achievement of treatment goals in patients with asthma in the majority of patients, with subsequent reductions in exacerbations, hospitalizations, primary care physician visits and sleep disturbances (19).
Effective patient education, via a variety of methods and healthcare professionals, has a fundamental role in good inhaler technique and the reduction in frequency of inhaler errors (9). Educational interventions have been shown to be more effective in adults than in children and are especially effective in the short term (20); periodic repetition of inhaler education is recommended (21). Furthermore, longer-term studies with periodic inhaler technique assessment and educational interventions are needed to define the most suitable schedule for mainte- nance of optimal inhaler technique (20).

Study limitations

The COMPRENDRE study has several limitations inher- ent to its observational nature. However, the results of this study of nearly 1400 patients provides “real-life” data that are necessary for a better understanding of DuoResp® Spiromax® usage conditions. The vast majority of physi- cians who enrolled patients were GPs and not respiratory specialists, in line with the treatment of non-severe asthma in France. Nevertheless, the COMPRENDRE study allows the definition of a profile of patients treated in clinical practice with DuoResp® Spiromax® and confirmation of its safety and ease of use.
One limitation is that this study was performed and analyzed before the publication of the CritiKal study (3). The CritiKal study defined specific inhaler errors as crit- ical errors on the basis of error frequency, asthma symp- tom control, and exacerbation rate, and proposed alternative definitions of critical errors. Critical or non-critical errors in the current study were defined according to the advice and experience of an expert panel; however, if the CritiKal definitions had been used in the current study protocol, it is likely that some additional critical errors would have been identified in the current dataset. For instance, the CritiKal study identified insuf- ficiency of inspiratory effort and lack of breath-hold fol- lowing inhalation, neither of which were defined by the panel as critical errors, as being significantly associated with poor asthma control and with exacerbations. Another issue to note is that use of a dose counter to assess adherence to treatment is not always reliable, and may have led to some errors in reporting of adher- ence data.
Comparison with the literature suggests a far lower rate of incorrect use for DuoResp® Spiromax® than with other DPIs (42–45%). However, it should be borne in mind that findings of handling errors among users of Symbicort® Turbuhaler® and Seretide® Diskus® were observed for patients who, in the vast majority of cases (79.1%) had been using their inhaler for over a year and for whom no information is available on the training received on these inhalers. These results are therefore certainly not comparable with those observed for DuoResp® Spiromax® after only 3 months of use. It is likely that additional training on existing devices would also have led to a reduction in errors after a period of 3 months. As the DuoResp® Spiromax® device was new to all of the enrolled patients and they were trained in its use, a long-term follow-up will be necessary to confirm that the correct use of DuoResp® Spiromax® is main- tained; the novelty aspect may have also biased patients’ preference for the device. Within the framework of the COMPRENDRE study, the usage conditions of DuoResp® Spiromax® could be determined for over 99% of patients, allowing the frequency and nature of handling errors to be evaluated for 1390 patients.

Conclusions

Patient education and correct device handling are crucial aspects of switching asthma therapy to a new device; inhaler technique, patient device preference and treatment adherence are interrelated factors which play an important role in asthma control. In particular, patient satisfaction with their device and inhaler technique are important fac- tors for physicians to assess where patients are receiving treatment but have uncontrolled asthma.
In this study a very low (12%) rate of critical errors associated with impaired asthma control was seen after 3 months of use of DuoResp® Spiromax®. Longer term studies are required to assess the durability of this benefit. These results highlight the potential benefits of switching devices in patients with inadequate asthma control and reinforce the importance of the correct use and simplicity of inhalation devices in good asthma management via effective training and demonstration.

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