Physicians' Knowledge of Inhaler Devices and Inhalation Techniques Remains Poor in Spain

Introduction

The development of aerosol delivery devices represented a significant breakthrough in the treatment of bronchial obstructive diseases, particularly asthma and chronic osbtructive pulmonary disease (COPD). It is now close to 60 years since the first device inhaler (Medihaler-Epi^™) was marketed, and with the technological advances made over these years, today's devices offer substantial improvements over their predecessors. A wide range of inhalers is now available, but although this means treatment can be individualized for each patient it also means physicians who prescribe these devices must keep abreast of all their characteristics, their potential drawbacks, and especially their inhalation technique.

Inhaled drugs provide clear advantages over other routes of administration, but they also have some limitations. The most serious of these is that patients must use them appropriately for a minimal amount of a drug to reach the low airways and exert its pharmacological action successfully. Incorrect use of inhaler devices can lead to therapeutic failure and poor disease control.^(1–3) For this reason, clinical practice guidelines for asthma and COPD consider that training patients to use their inhalation devices is as an essential part of nonpharmacological aspects of treatment.^(4–6) For the same reason, the European Respiratory Society (ERS) and the International Society for Aerosols in Medicine (ISAM) recently developed a consensus statement for the pulmonary physician that includes detailed recommendations on how to use inhalation devices correctly.⁽⁷⁾

Several studies have shown that most patients who use inhaler devices do not handle them properly.^(8–13) It has also been observed that physicians and nurses who prescribe or supervise these inhalers have poor knowledge and skills regarding their use.^(14–17) Results in Spain from studies performed in the 1990s reflected similar findings.^(18–20) In view of these shortcomings, scientific societies and pharmaceutical industries in Spain have since developed and launched a series of educational activities (meetings, postgraduate courses, workshops, and recommendation documents supported by the scientific societies^(21–22) addressed to physicians to improve their knowledge on inhalation therapy. To assess physicians' current knowledge of inhaled therapy we conducted a survey in a large sample of physicians from various medical specialties that commonly prescribe inhaler devices.

Materials and Methods

Results

A total of 1514 respondents completed the questionnaire. The mean age of the sample was 44.5 [confidence interval (CI) 95%: 44–45] years and 830 (55%) were men. Regarding medical specialty, 652 (43%) were pneumologists, 307 (20.2%) were primary care physicians, 270 (17.8%) were allergists, 266 (17.6%) were internal medicine physicians, and 19 (1.2%) were from other specialties. Respondents came from the following areas of Spain: 493 (32.6%) were from eastern regions, 451 (29.8%) were from the central area, 291 (19.2%) were from the south, 218 (14.4%) were from the north, and 34 (2.2%) were from the Canary Islands or Ceuta-Melilla.

Table 2 displays the results for the whole sample interviewed for items 5, 6, 7, 8, 9, 10, and 11, and compares the results observed by specialty group. For the item 5 (“Your knowledge of inhaler use comes mainly from”) responses showed no clear origin of learning, but when groups of specialty were compared significantly more pneumologists (34%) chose the option ”reading articles or books specialized on the topic”. For the item 6 (“Which device do you prefer?”), DPIs (Turbuhaler^™ and Diskus^™) were selected by 61.2% of the physicians and a significant proportion of primary care physicians (24.3%) preferred the pMDI Modulite^™ system than other specialty groups. Results for item 7 (“The most important step for correct pMDI inhalation is”) showed that a high proportion of participants (72.3%) chose the correct answer (“Firing the device after beginning inspiration”), but primary care physicians (5.9%), more than any other group, stated incorrectly “shake the device before inhalation.” In the Item 8 (“The most important step for correct DPI inhalation is”) only 46.1% of the physicians sample identified “inhale deeply and forcefully” as the correct answer. Results for item 9 (“When you prescribe an inhaler device, which of the following variables do you consider most important?”) revealed that only 12.3% of the physicians selected the “patient's preferences,” and between specialty groups, pneumologists significantly chose more frequently this option than any other group. Item 10 asked about educational aspects (“When you prescribe a new inhaler do you or another healthcare worker assess the patient's skill with its use?”) where only 27.7% of the sample stated that they “always” checked the patient's skill and by groups, pneumologists and allergists had significantly higher response rates (32.4 and 30%, respectively) in this answer option than other analyzed groups. Finally, for item 11 (“Who trains the patients in the device inhaler technique in your centre?”) the internal medicine group showed a lower involvement to train patients in the inhalation techniques.

The composite variable generated, general inhaled therapy knowledge, showed an average score of 1.53 points (95% CI: 1.48–1.57) in the sample of the four specialties (pneumology, allergy, primary care, and internal medicine) analyzed (1495). Fourteen respondents (0.9%) achieved the highest possible score (four points) and 170 (11.4%), the lowest possible score (zero points). Pneumologists [1.66 (95% CI: 1.59–1.73)] and allergists [1.65 (95% CI: 1.54–1.75)] achieved a significantly higher mean score than primary care [1.36 (95% CI: 1.27–1.46)] and internal medicine physicians [1.28 (95% CI: 1.17–1.38)] (p<0.05). According to the stratification established, 1283 (85.8%) respondents were classified into the poor inhaled therapy knowledge group and 212 (14.2%) were classified into the adequate group. Table 3 shows the differences between specialties: the proportion of pneumologists and allergists in the adequate group was significantly higher than that of primary care and internal medicine physicians. Neither gender nor age was significantly associated with general inhaled therapy knowledge score. Multivariate analysis to predict adequate general inhaled therapy knowledge revealed (Table 4) that pneumologists and allergists doubled the odds ratio (2.33 and 1.98, respectively) of primary care and internal medicine physicians.

Discussion

A very high proportion of physicians who frequently prescribed inhaler devices lacked adequate knowledge concerning inhaled therapy and related educational aspects. The composite variable, general inhaled therapy knowledge, which pooled the answers of the four related items on the questionnaire, identified only 14.2% of the sample as having adequate knowledge of inhaled therapy. Several studies have consistently shown poor asthma control,^(28–30) and it has been suggested that one cause could be the inappropriate use of inhalers.^(1–3) In a recent prospective study involving 1664 (COPD and asthma) patients Melani et al.⁽³¹⁾ observed a strong association between increased unscheduled healthcare resource use and poor clinical control with an inappropriate use of their inhaler devices. Fortuna et al.⁽³²⁾ found that although 76% of 1363 patients with asthma were treated with a combination of inhaled corticosteroid plus a long-acting beta agonist, 44% of the total sample had suffered a moderate to severe asthma exacerbation in the previous year. As the pharmacologic treatment prescribed follows present guidelines, issues such as incorrect inhalation techniques could be involved in these unexpectedly low results.

Item 5 was related to the source of inhaled therapy knowledge and responses showed no clear origin of learning. This could therefore be another aspect to take into account in the future to improve physicians' knowledge of inhaled therapy. Perhaps this topic should be included in the academic curriculum at medical school, where, at least in our country, it is not given proper attention.

Item 6 explored physicians' choice concerning the type of inhaler. The Turbuhaler^™ and Diskus^™ DPI devices were the preferred inhalers by 61.2% of physicians who completed the questionnaire. This finding contradicts recent sale figures indicating that pMDI is the most widely sold device in Spain.⁽³³⁾ However, these differences observed between our results and the sale rates could be related to the fact that the number of pneumologists interviewed (43%) was higher than the number of primary care physicians (20.2%) interviewed. The proportion of preferences for DPI was higher in pneumologists and allergists than in primary care and internal medicine physicians. An alternative explanation could be related to the higher drugs available in DPI, particularly combinations of inhaled corticosteroid plus a long-acting beta agonist, than pMDI in Spain. Another finding that deserves comment is that although DPI was the preferred device by 61.2% of physicians, only 46.1% correctly identified “inhale deeply and forcefully” as the most important step for the DPI inhalation maneuver (see Table 2). This inconsistency adds to the general deficiencies identified in knowledge of inhalation therapy in the sample surveyed.

Seventy-two percent of our sample successfully identified the critical step for the pMDI and 46.1% identified that for the DPI, results that were similar to studies from other countries.^(16,17) Two studies conducted in Spain 15 years ago to evaluate healthcare professionals' skills in the use of inhalation devices asked participants to give a practical demonstration with a placebo inhaler.^(19,20) One of these studies showed that only 28% of 428 physicians managed the pMDI correctly,⁽¹⁹⁾ and the other showed that only 27% of 118 physicians and nurses used the Turbuhaler^™ DPI correctly.⁽¹⁹⁾ Our present results may therefore imply an improvement compared to the above-mentioned studies,^(19,20) but the different methods used must be taken into account when interpreting the findings. The use of multiple choice questions to assess self-referred knowledge, not dexterity, on the inhalation technique has been successfully used by several investigators.^(34,35) However, it is more challenging and exacting to achieve optimum scores when a practical demonstration with a placebo device is requested, as in our former studies,^(19,20) than when participants are only asked to identify the critical maneuver from a multiple choice list. Moreover, this improvement in knowledge about the pMDI inhalation technique could have been favored by the fact that the same phrasing was used in answers to items 7 and 8 (the most important steps for correct pMDIs and DPI's inhalation techniques, respectively). This could have made it easier to identify the right answer for the correct inhalation technique (item 7).

The survey noted two main deficiencies related to inhaler training for patients. The first of these was related to item 9, which asked physicians to identify the most relevant characteristic to take into account when prescribing a device. Only 12.3% chose “patient's preferences.” The second deficiency related to inhaler training concerned item 10 where only 27.7% of physicians responded that they “always” checked patient skill in using the device at the moment of prescription, and 5.4% and 1.1% ticked the “hardly ever” or “never” boxes, respectively. These findings are those of most concern in our study and they are consistent with the responses to item 9. The score for general inhaled therapy knowledge was weighed down by the poor results observed in items 9 and 10, emphasizing the need to specifically address these educational aspects in future educational programs.

As in the studies mentioned earlier,⁽²⁰⁾ when our results were compared between specialty groups, pneumologists and allergists showed significantly better scores than primary care and internal medicine physicians for all items and also, therefore, in the combined variable generated (general inhaled therapy knowledge). In the multivariate analysis, pneumology and allergy specialists, doubled the “odds ratio” (2.33 and 1.98, respectively) for “adequate knowledge” in inhaled therapy in comparison with other groups. This finding is of particular clinical relevance given the large volume of chronic respiratory patients (asthma and COPD) attended to by primary care physicians and internal medicine physicians in routine care and the emergency room when patients present exacerbations. Specific educational policies should be addressed to both these medical groups. Given our failure to improve general inhalation therapy knowledge with traditional educational methods, different strategies should be devised. These should include inhalation therapy topics to be addressed during residency training and in recertification programs.

One of the potential weaknesses of this study could be related to the method used. The data are based solely on the results of a survey on self-perceived knowledge and may not reflect respondents' behavior in actual clinical practice.

To conclude, physicians who manage respiratory patients in Spain continue to have a poor knowledge of inhaler devices and inhalation techniques. Despite the educational activities developed in the past 20 years, information on the use of aerosols does not appear to have improved substantially. Further studies are needed to identify the causes of this continued deficiency. New educational programs should be developed, and general practitioners should be specifically addressed.