Assessment of Adherence to Controller Inhalation Medication in Asthma- and COPD Patients.
Assessment of Adherence to Controller Inhalation Medication in Asthma- and COPD Patients.
The main aim of the study is to evaluate the adherence to controller inhalation medication in
 asthma and Chronic Obstructive Pulmonary Disease (COPD) in Universitair Ziekenhuis Brussel.
 Adherence will be assessed using the 12-question Test for the Adherence to Inhalers (TAI)
 yielding a score indicating level of adherence (high, intermediate or poor). The TAI also
 provides some indication about the possible mechanisms of non-adherence (sporadic, deliberate
 or unconscious). The aim of the study is also to compare the adherence between the 2 study
 subgroups (asthma and COPD patients). Several other factors which could influence the
 compliance of the patients will also be evaluated: age, sex, pack years, FEV1 (Forced
 Expiratory Volume 1), exacerbation history, symptom control, type of inhaler and number of
 inhalers. By identifying different patient and treatment characteristics that lead to
 non-adherence, future education efforts could be better targeted to these patients presenting
 the most important unmet need in terms of adherence.
Adherence to the controller inhalation medication is an important component of asthma and
 COPD care. Good adherence to the prescribed medication is asthma patients is associated with
 better symptom control and improved lung function. Also, lower exacerbation rate and
 mortality risk, less healthcare utilisation, lower healthcare-associated costs and a better
 quality of life are linked with better adherence in asthma and COPD patients.

 However, studies have shown that the adherence to therapy in chronically ill patients
 averages around 50%. In asthma patients the level of adherence varies between 30-70%, while
 compliance rate in COPD patients is around 20-60% (though the numbers vary). Adherence in
 asthma and COPD patients is thus generally low.

 Adherence in these patients is measured in studies in different ways: electronic device
 monitoring, dispensing data, drug levels or several self-administered questionnaires, among
 others. Each technique has its own benefits and drawbacks. However, the easiest to use are
 the self-administered questionnaires. Although many of these exist, a particularly
 interesting questionnaire is the TAI (Test for the Adherence to Inhalers). It exists in 2
 versions: a 10-question and a longer 12-question test. The 12 question TAI has 2 added
 questions, in which a healthcare professional evaluates the use of the inhaler by the
 patient. All 12 questions can then be used to identify different non-compliance behavioural
 patterns. The advantages of this questionnaire are therefore that it can be used for both
 asthma and COPD patients, that it is designed specifically for inhalation medication and that
 it not only measures adherence but also the type of non-compliance .

 The main aim of the study is thus to evaluate the adherence to controller inhalation
 medication in asthma and COPD in Universitair Ziekenhuis Brussel. Adherence will be assessed
 using the 12-question TAI (Test for the Adherence to Inhalers). The aim of the study is also
 to compare the adherence between the 2 study subgroups (asthma and COPD patients). Several
 other factors which could influence the compliance of the patients will also be evaluated:
 age, sex, pack years, FEV1, exacerbation history, symptom control, type of inhaler and number
 of inhalers. By identifying different patient and treatment characteristics that lead to
 non-adherence, future education efforts could be better targeted to these patients presenting
 the most important unmet need in terms of adherence.

 Patient recruitment will take place at the Universitair Ziekenhuis Brussel respiratory
 outpatient clinic. Before their scheduled appointment, patients they will be screened to
 participate in the study. Recruitment will start January 2019 until March 2019, or until the
 target number of patients is reached. On the day of their appointment, the participants will
 receive all necessary information about the study and the informed consent process from the
 principal investigator.

 Patients will have sufficient time to reflect on their participation in this study and to ask
 questions. After obtaining the written informed consent from the patients, the necessary
 interventions (filling in questionnaires and gathering information from the patients files)
 will take place.

 It will be allowed for the patients to provide informed consent and to participate in the
 study on a later date.

 Statistical analysis:

 The statistical analysis will be conducted in 3 steps :

 1. Preliminary one-way ANOVA to evaluate the dependent variable (TAI level of adherence)
 for each independent variable.

 2. A multi-way ANOVA model will be constructed to include the relevant independent
 variables and potential two-way interactions, by maximization of adjusted R2 obtained
 through a backward elimination in order to correct for multicollinearity.

 3. In a final step, the model residuals will be checked to satisfy the normality condition
 through application of the Kolmogorov-Smirnov and Shapiro-Wilk tests, also exploring the
 influence of potential heteroscedasticity.
Inclusion Criteria:

 -  Asthmatics with treatment ≥ GINA step 2.

 -  COPD-patients , GOLD stage II-IV.

 Exclusion Criteria:

 -  No spirometry results available.

 -  COPD patients not on long-acting bronchodilators.