Abstract
The effect of patient education on steroid inhaler compliance and rescue medication utilization in patients with asthma or chronic obstructive pulmonary disease (COPD) has not been previously investigated in a single study. We randomized 78 asthmatics and 62 patients with COPD after ordinary outpatient management. Intervention consisted of two 2-h group sessions and 1 to 2 individual sessions by a trained nurse and physiotherapist. A self-management plan was developed. We registered for 12 mo medication dispensed from pharmacies according to the Anatomical Therapeutic Chemical (ATC) classification index. Steroid inhaler compliance (SIC) was defined as (dispensed/prescribed) × 100 and being compliant as SIC > 75%. Among asthmatics 32% and 57% were compliant (p = 0.04) with a median (25th/75th percentiles) SIC of 55% (27/96) and 82% (44/127) (p = 0.08) in the control and intervention groups, respectively. Patient education did not seem to change SIC in the COPD group. Uneducated patients with COPD were dispensed double the amount of short-acting inhaled β2-agonists compared with the educated group (p = 0.03). We conclude that patient education can change medication habits by reducing the amount of short-acting inhaled β2-agonists being dispensed among patients with COPD. Educated asthmatics showed improved steroid inhaler compliance compared with the uneducated patients, whereas this seemed unaffected by education in the COPD group. Gallefoss F, Bakke PS. How does patient education and self-management among asthmatics and patients with chronic obstructive pulmonary disease affect medication?
Medication regimens for patients with asthma or chronic obstructive pulmonary disease (COPD) are particularly vulnerable to adherence problems because of the chronic nature of the diseases, the use of multiple medications, and the periods of symptom remission. Rates of noncompliance in the treatment of asthma may vary from 20 to 80% (1). Factors leading to poor compliance are not fully understood, but lack of education may be one cause (1).
Previous surveys in asthmatics examining the effect of education programs on compliance have shown conflicting results. Windsor and coworkers (2) reported from a study in 267 adult asthmatics that patient education consisting of one individual and one group session gave significantly improved medication adherence compared with the control group after a 1-yr follow-up. In a controlled intervention study of 116 asthmatics Allen and coworkers (3) observed an increased compliance 12 mo after a 2.5 × 4 h group session. The Grampian Asthma Study of Integrated Care (GRASSIC) did not show any change in the use of bronchodilators or inhaled steroids after an enhanced education program (4). In two of the studies cited (2, 3) the compliance was self-reported, whereas the third study (4) based the compliance data on medication prescribed by the patients' doctors. Only one of the studies presented data on inhaled steroid compliance (4). No data are available regarding the effect of patient education on medication adherence in the Nordic countries. To our knowledge data are lacking on the effect of patient education on compliance in patients with COPD as well as comparable studies on asthma and COPD.
We performed a randomized, controlled intervention study in patients with mild to moderate asthma or COPD using a standardized education program and a self-management plan. The objectives of the present report are to assess the effect of patient education on antiobstructive medication dispensed from pharmacies.
Between May 1, 1994 and December 1, 1995, 140 consecutive patients were included in the study after having received ordinary consultation care at our outpatient chest clinic at Central Hospital of Vest-Agder, Kristiansand, Norway. At inclusion they signed a written consent and were then randomized to an intervention group or a control group. The control group were followed by their general practitioners, and the intervention group received an education program and were then also transferred to a 1-yr follow-up by their general practitioners (Figure 1).
Eligible subjects were patients with bronchial asthma or COPD between 18 and 70 yr of age, not suffering from any serious disease, such as unstable coronary heart disease, heart failure, serious hypertension, diabetes mellitus, kidney or liver failure.
Subjects with stable asthma were to have a prebronchodilator FEV1 equal to or higher than 80% of predicted value (5). Furthermore we required either a positive reversibility test (5), a documented 20% spontaneous variability (peak expiratory flow [PEF] or FEV1), or a positive methacholine test (provocative dose causing a 20% decrease in FEV1 [PD20]) (6). A positive reversibility test required at least a 20% increase (FEV1 or PEF) after inhalation of 400 μg salbutamol. Because we wanted to include those with mild COPD, subjects with COPD were to have a prebronchodilator FEV1 equal to or higher than 40% and lower than 80% of predicted (7). Among patients with COPD 32% were reversible to ipratropium bromide 80 μg and/or salbutamol (8, 9). These measures were obtained from the participants' charts.
Of the eligible patients, the inclusion rate was 92% (78 of 85) and 91% (62 of 68) for the asthma and COPD group, respectively.
The educational intervention has been thoroughly described (10). Briefly, it consisted of a specially constructed patient brochure, two 2-h group sessions (separate groups for asthmatics and patients with COPD) concentrating on pathophysiology, antiobstructive medication, symptom awareness, treatment plans, and physiotherapy. One or two 40-min individual sessions were supplied by both a nurse and a physiotherapist (Figure 1). With regard to antiobstructive medication the following was emphasized: The components of obstruction were explained together with the site of action of the actual medication. The patient's pulmonary symptoms were registered and discussed with emphasis on the early symptoms experienced at exacerbations. The individual factors causing attacks/exacerbations and concerns regarding adverse effects of medication were discussed and inhalation technique was checked. At the final teaching the patients received an individual treatment plan on the basis of the acquired personal information and 2 wk of peak flow monitoring (10). The personal understanding of the treatment plan with regard to changes in PEF and symptoms was discussed and tested (Table 1).
| Color Code | PEF* | Symptoms | Treatment | |||
|---|---|---|---|---|---|---|
| Green | > 80% | No symptoms; occasional use of inhaled | Maintenance treatment | |||
| β2-agonist | ||||||
| Yellow | 80–60% | Start of a cold; night symptoms; cough; | Double or triple dosage of inhalation steroids until | |||
| or increased use of inhaled β2-agonists | back in green zone, then continue double or triple | |||||
| dosage for as long a time as outside green zone | ||||||
| Orange | 60–40% or | The effect of inhaled β2-agonists lasts | Prednisolone 30–40 mg/d until back in green | |||
| > 150 L/min | < 2 h; shortness of breath on exertion | zone, then 10–20 mg/d for as long a time as | ||||
| outside green zone | ||||||
| Red | < 40% or | Inhaled β2-agonists of little help or | Take prednisolone 40 mg and high-dose inhaled | |||
| < 150 L/min | effect lasts < 30 min; shortness of | β2-agonist and contact doctor immediately | ||||
| breath when talking |
All patients received treatment plans aimed at making early changes in medication at exacerbations. Among the educated asthmatics, 94% received standard treatment plans incorporating peak flow monitoring (Table 1). In the COPD group 12 of 26 (46%) received standard treatment plans. Nonstandard treatment plans incorporated the use of oral steroids as the first line of action in the yellow zone if, for example, the patient already used high dosages of inhalation steroids as maintenance therapy or could tell that a double or triple increase in inhalation steroids previously had marginal effect on the course of attacks/exacerbations. Among those 14 patients with COPD receiving nonstandard treatment plans, eight patients did not want to or were not able to use peak flow monitoring as a basis for change in medication. For those patients, only symptom-based treatment plans were issued (Table 1).
All medication was coded to Defined Daily Dosages (DDD) according to the Anatomical Therapeutic Chemical (ATC) classification index (11, 12) for comparison of medication within the same chemical–therapeutic groups, thus allowing us to compare those using, for instance, beclomethasone and budesonide. Prescribed Defined Daily Dosage (PDDD) of regular medication (11, 12) is expressed as the regular dosage recommended by the lung clinic at baseline. Short-acting β2-agonist inhalations were in this study categorized as rescue medication because it was not recommended as regular medication. Dispensed medication was reported from all local pharmacies through monthly print-outs from the pharmacy data registers. At the 1-yr follow-up all patients were asked whether they had received medication elsewhere. Only one individual reported this and the data were included.
Compliance of regular medication was calculated as a percentage: (dispensed DDD/PDDD) × 100 during the 1-yr follow-up. Standard definition of compliance differs in the literature and is variably defined to values from 70% (13, 14) to 90% (3). We defined a priori the patient as compliant when dispensed regular medication was greater than 75% of prescribed regular medication during the study period (15).
Number of prednisolone courses was retrospectively self-reported at 12 mo follow-up. Prebronchodilator spirometry was performed before randomization and at 12 mo follow-up by standard methods (5) using a Jaeger MasterLab Body Box (Würzburg, Germany). The technical staff did not know whether the patients belonged to the control or intervention groups.
A number of the outcome variables showed skewed distribution as judged by normality plots, and Lilliefors' test for normality with p < 0.05 and then median (the value that separates the highest 50% of the scores from the lowest 50%) values are shown as a measure of central tendency with the 25th and 75 percentiles (the interquartile range) as a measure of dispersion. For normally distributed data the measures of central tendency and dispersion are mean and standard deviation (SD), respectively. The nonparametric Mann-Whitney U test was applied when comparing continuous, skewed variables between groups. Chi-square test was applied for categorized dependent variables also giving the odds ratio. All tests were done two-sided. An alpha < 0.05 was considered statistically significant.
When testing the correlation between the change in FEV1 over the study period and steroid inhaler compliance (SIC) and between dispensed β2-agonist inhalation DDD and SIC, bivariate nonparametric correlation analysis (Spearman's correlation coefficient rho [ρ]) was applied.
All analyses were performed on Compaq computers applying SPSS version 7.5 (SPSS Inc., Chicago, IL). Permission to establish a person register was given from the National Data Supervision Center. The methodological procedures were in accordance with the ethical standards of the Helsinki Declaration as approved by the regional ethical committee.
The study population consisted of 140 patients, with 39 patients randomized to each asthma treatment group and 31 to each COPD treatment group. The baseline parameters are shown in Table 2.
| Asthma | COPD | |||||||
|---|---|---|---|---|---|---|---|---|
| Control Group | Intervention Group | Control Group | Intervention Group | |||||
| (n = 39) | (n = 39) | (n = 31) | (n = 31) | |||||
| Sex, women, n (%) | 31 (79) | 24 (62) | 15 (48) | 16 (52) | ||||
| Age, yr, mean ± SD | 44 ± 12 | 41 ± 12 | 58 ± 10 | 57 ± 9 | ||||
| Smoking habits | ||||||||
| Current smokers, n (%) | 13 (33) | 9 (23) | 12 (39) | 12 (39) | ||||
| Pack-years, median* | 11 | 6 | 17 | 17 | ||||
| Ex-smokers, n (%) | 11 (28) | 14 (36) | 19 (61) | 15 (48) | ||||
| Never-smokers, n (%) | 15 (39) | 16 (41) | 0 | 4 (13) | ||||
| Current use of peak flow meter, n (%) | 12 (31) | 16 (41) | 4 (13) | 9 (29) | ||||
| FVC% pred, mean ± SD | 105 ± 15 | 104 ± 12 | 90 ± 12 | 88 ± 14 | ||||
| FEV1% pred, mean ± SD | 95 ± 17 | 93 ± 13 | 56 ± 11 | 59 ± 9 | ||||
| PEF% pred, mean ± SD | 107 ± 25 | 106 ± 19 | 70 ± 19 | 69 ± 20 | ||||
Table 3 shows the mean PDDD per year at randomization in the control and intervention groups. In the asthma group 96% used inhalation steroids at randomization amounting to a mean (± SD) steroid inhaler PDDD of 313 ± 164. The corresponding numbers in the COPD group were 92% and 439 ± 216, respectively. Eighty-one percent and 14% of the asthmatics used one and two regular medications, respectively compared with 60% and 23% in the COPD group.
| Asthma | COPD | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Control (n = 39) | Intervention (n = 39) | Control (n = 31) | Intervention (n = 31) | |||||||||||||
| n (%) | PDDD* | n (%) | PDDD* | n (%) | PDDD* | n (%) | PDDD* | |||||||||
| Inhalation steroids | 38 (97) | 335 ± 161 | 37 (95) | 294 ± 164 | 27 (87) | 476 ± 216 | 30 (97) | 406 ± 200 | ||||||||
| Long-acting β2-agonist inhalations | 3 (8) | 425 ± 105 | 10 (26) | 383 ± 134 | 8 (26) | 387 ± 152 | 11 (36) | 373 ± 193 | ||||||||
| Ipratropium bromide inhalations | 2 (5) | 364 ± 171 | 2 (5) | 486 ± 0 | 12 (39) | 455 ± 75 | 12 (39) | 455 ± 105 | ||||||||
| Xanthine derivative tablets | 1 (3) | 638 | 0 | 3 (10) | 577 ± 105 | 3 (10) | 638 | |||||||||
| β2-Agonist tablets | 0 | 1 (3) | 365 | 0 | 1 (3) | 486 | ||||||||||
| Steroid tablets | 2 (5) | 182 ± 128 | 1 (3) | 97 | 2 (7) | 227 ± 64 | 3 (10) | 151 ± 52 | ||||||||
Among the asthmatics the proportion of patients with SIC above 75% in a 1-yr follow-up (Figure 2) was almost twice (57/ 32 = 1.8) as large in the educated group as in the control group (p = 0.04). The odds ratio for having a SIC > 75% were 2.8 (95% confidence interval: 1.1 to 7.7) in the educated group compared with the control group. No significant difference was observed between the COPD treatment groups. Table 4 shows the median compliances for the regular medication. In the asthmatics the median SIC was higher in the intervention than in the control group, the difference being of borderline statistical significance (p = 0.08). For the compliances of the other regular medications no overt differences were observed between the intervention and control groups, but the small numbers did not allow sound statistical analyses and should be interpreted with caution.
Fig. 2. Proportion of patients with steroid inhaler compliance > 75% during a 1-yr follow-up.
[More] [Minimize]| Asthma | COPD | |||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Control Group (n = 39) | Intervention Group (n = 32) | Control Group (n = 27) | Intervention Group (n = 26) | |||||||||||||||||||||||||
| n | Median | 25th/75th Percentiles | n | Median | 25th/75th Percentiles | p Value | n | Median | 25th/75th Percentiles | n | Median | 25th/75th Percentiles | p Value | |||||||||||||||
| Steroid inhaler | 38 | 55 | 27/96 | 30 | 82 | 44/127 | 0.08 | 24 | 82 | 31/134 | 24 | 85 | 51/110 | 0.94 | ||||||||||||||
| Long-acting β2 inhaler | 3 | 90 | 44/90 | 9 | 74 | 37/97 | 0.93 | 6 | 82 | 47/115 | 7 | 99 | 74/99 | 0.94 | ||||||||||||||
| Ipratropium bromide inhaler | 2 | 134 | 103/165 | 1 | 134 | 1.00 | 10 | 62 | 50/100 | 12 | 81 | 57/109 | 0.37 | |||||||||||||||
Among the asthmatics 26 of 71 (37%) did not collect short-acting β2-agonist inhalations (rescue medication) at the pharmacies; in the COPD group the corresponding ratio was six of 53 (11%) (p = 0.001, chi-square test). Figure 3 shows the amount of short-acting β2-agonist inhalations being dispensed during a 1-yr follow-up. The educated patients with COPD received less than half the amount of rescue medication compared with the control group. In the asthmatics a similar tendency was observed, but the difference was not statistically significant. Nine subjects in both asthma treatment groups (p = 0.63, chi-square test) reported a median (25th/75th percentiles) number of two (1/2) steroid courses (p = 0.86, Mann-Whitney U test) during the 1-yr follow-up. Eighteen of 26 (69%) educated COPD patients reported steroid courses compared with 12 of 27 (44%) in the control group (p = 0.07, chi-square test) among which a median (25th/75th percentiles) of three (1/4) and four (1/7) steroid courses were recorded, respectively (p = 0.42, Mann-Whitney U test). The COPD control patients who needed steroid tablets were dispensed a median (25th/75th percentiles) of 100 (58/181) DDD compared with 200 (100/288) DDD in the educated group (p = 0.02), but then steroid tablets as a rescue medication (being dispensed in advance as a “just in case” medication) was included for the educated group. If rescue medication was subtracted, the median (25th/75th percentiles) number of reported steroid courses for the COPD intervention group was 125 (100/425) DDD, and the difference was no longer statistically significant (p = 0.21).
Fig. 3. Dispensed short-acting β2-agonist inhalations as DDD during a 12-mo follow-up stratified by treatment group.
[More] [Minimize]Bivariate nonparametric correlation analysis between SIC and dispensed β2-agonist inhalation DDD showed a weak association for the asthma group (Spearman's ρ = 0.36, p = 0.03), the higher the DDD of steroid inhalers received, the higher the received DDD of short-acting β2-agonist inhalations (rescue medication). This correlation tended to be stronger in the educated asthma group (Spearman's ρ = 0.49, p = 0.006) than in the control group (Spearman's ρ = 0.27, p = 0.11). No such correlation was found for the COPD group (Spearman's ρ = 0.16, p = 0.29).
Bivariate nonparametric correlation analysis between change in FEV1 as dependent variable and SIC showed no correlation (Spearman's ρ = 0.04 and 0.22, p = 0.75 and 0.13) for the asthma group and patients with COPD, respectively.
Our study showed that patient education emphasizing self-management and control of exacerbations in asthmatics gave a better SIC when compared with traditional treatment at our outpatient clinic with general practitioner (GP) follow-up. SIC seemed unaffected by patient education in the COPD group, while the need for short-acting β2-agonist inhalations as rescue medication was doubled in the uneducated group. Use of oral steroids did not differ significantly between the intervention and control group, neither among the asthmatics nor in the patients with COPD.
Evaluation of compliance in the present study was based on the dispensed DDD from pharmacies. The method is regarded as useful for measuring compliance with long-term medication regimens (16). It is unobtrusive, not reminding the patients of the registration going on, thereby reducing the bias of the study itself. However, the method provides no information about daily patterns of medication use (medication adherence) and gives a coarse and probably overestimated measure of compliance, since return of issued medication was not measured.
There are several alternative methods available for measuring compliance. First, self-reported medication/asthma diaries could have been used giving more exact knowledge, especially about change in medication, but this method has highly variable validity (16). Patient adherence to asthma diaries over time is frequently poor. Asthma diary data are also vulnerable to patient deceit (16). Second, medication monitors (electronic monitors recording date and time of medication use) could be an applicable alternative, but this is an expensive method. In addition, we would have had to adjust this type of equipment to many different devices. Patients could also react on the presence of a monitoring device, altering natural patterns of medication use (16). In our setting the retrospective interpretation of such data for 12 mo would be difficult and would necessitate more frequent controls for safe interpretation of data, which again would increase the bias on compliance in the study.
Regarding inhaled steroids, we found a higher degree of complying (compliance > 75%) subjects among educated compared with uneducated asthmatics. The educated asthmatics were almost two times as likely to be steroid inhaler compliant compared with the uneducated. This finding is in alignment with previous self-management studies (2, 3). However, the present study is the first to show such a finding when compliance is not self-reported. There might be several reasons for this observation. It could reflect a basically better adherence to recommended regular medication, but could also have been influenced by compliance to the self-management plan which recommended higher doses during exacerbations, as found by others after patient education (17, 18). It is likely that both factors influenced our result. The degree of noncompliance in the educated asthma group was, however, still unsatisfactory.
As many as 90% of the patients with COPD used inhaled steroids. These high figures reflect the liberal use of such medication for the patients with COPD in Norway when the study was conducted (19). Patient education did not alter SIC in the COPD group. However, the results should be interpreted with caution owing to limited ability to detect these differences in the COPD groups. There may be several reasons for the presumed lack of difference in SIC between groups: The educational method, the rationale for regular use of medication, and a stepwise self-management plan may all be more easily adjusted, incorporated, and justified for asthmatics than for patients with COPD. SIC was equivalent in both the COPD control and intervention group to the compliance attained in the educated asthma group; this finding could be explained by the fact that patients with COPD might have experienced more daily symptoms than asthmatics, which may have reinforced the use of regular medication. To our knowledge, the effect of an education program on SIC in patients with COPD has not been previously investigated. Prescription charges are not likely to have influenced our results because the maximum amount a Norwegian citizen must pay from his or her own pocket per year for medication and total medical treatment (hospital included) is approximately $US 150.
The short-acting β2-agonist inhalations dispensed to the uneducated groups were approximately twice as high as in the educated groups, but the difference was only statistically significant for the COPD group. These figures imply that the uneducated COPD patient took approximately two extra inhalations of either salbutamol 0.2 mg/d or terbutaline 0.5 mg compared with the educated. There could be several reasons for this finding: Educated patients with COPD might have had less daily symptoms than uneducated patients or might have treated their exacerbations more effectively. A greater tolerance to symptoms without the use of rescue medication could also partly explain the figures for the educated COPD group.
The short-acting β2-agonist results dispensed to the asthma group should be interpreted with caution because seven more persons in the educated group were on long-acting β2-agonists at randomization compared with the uneducated group. The reduced use of β2-agonists in the educated asthma group could theoretically be explained by the higher SIC, but an opposite correlation was found. Among asthmatics increased SIC was correlated to increased use of β2-agonists. Interpretation of this finding should be cautious, but could support a theory that those who needed more inhalation steroids presumably were sicker and so might also have used more β2-agonists. Patient education seemed to strengthen this correlation.
We cannot explain what part of the education influenced compliance, but we emphasized the regular use of steroid inhalations to avoid the daily use of β2-agonists. An overall impression was that the educated group had been more aware of their symptoms and the effect of their change in medication according to their self-management plan.
We conclude that patient education can change medication habits toward more desirable goals by reducing the collection of short-acting inhaled β2-agonists among patients with COPD. Educated asthmatics showed improved SIC while this seemed unaffected by education in the COPD group.
The authors thank the following pharmacies for their smooth cooperation in this study regarding the registration of dispensed medication: Sykehusapoteket i Kristiansand, Elefantapoteket, Lveapoteket, Randesund apotek, Vågsbygd apotek, and Vennesla apotek. They also acknowledge Ole Høie, M.D., for his neat and robust adaptation of DataEase for registration of the study parameters, the consistent and precise registration work done by Signe Valebrokk (project nurse), the educational support from Aud Salveson (pharmacist), and support with the study PC from Astri Thorsen on behalf of our Hospital Pharmacy.
Supported by the Norwegian Medical Association's Fund for Quality Improvement.
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