Beliefs about medicines predict refill adherence to inhaled corticosteroids

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Abstract

Objective

Despite the importance of the chronic use of inhaled corticosteroids (ICS) in maintaining asthma control, reported adherence varies between 40% and 60%. The Beliefs about Medicines Questionnaire (BMQ) has been shown to correlate with self-reported adherence. The aim of this study is to investigate whether beliefs about ICS (necessity and concerns), as measured by the BMQ, relate to adherence objectively measured by prescription-refill records.

Methods

In a cross-sectional study of patients aged 18–45 years who filled at least two ICS prescriptions in 11 community pharmacies in The Netherlands, perceptions of ICS were assessed using the BMQ. Additionally, self-reported adherence was assessed using the Medication Adherence Report Scale.

ICS prescription-refill adherence rates for a 12-month period prior to the survey were obtained from automated pharmacy dispensing records.

Four attitudinal groups were defined using the necessity and concerns constructs. Statistical tests were used to examine associations between ICS adherence (assessed by subjective self-report and objective pharmacy records), specific beliefs about and attitudes towards ICS, and more general beliefs about pharmaceuticals.

Results

Questionnaires were returned by 238 patients (51.1%). Both self-reported adherence (r=.38) and adherence by pharmacy records (ρ=0.32) correlated with ICS necessity beliefs and concerns. Patients defined as skeptical, indifferent, ambivalent, or accepting, on the basis of these constructs, differed with respect to both their attitudes towards medicines in general and their adherence to medication.

Conclusions

Patients' beliefs about ICS correlate not only with adherence by self-report but also with a more objective measure of medication adherence calculated by pharmacy dispensing records. The necessity–concerns constructs offer a potentially useful framework to help clinicians elicit key treatment beliefs influencing adherence to ICS.

Introduction

Appropriate use of inhaled corticosteroids (ICS) has been shown to be beneficial for maintaining disease control in patients with mild to moderate asthma [1], [2]. For over a decade, the core pharmacological management of asthma has focused on preventer therapy with ICS [3]. Despite the importance of the regular use of ICS, low adherence rates have repeatedly been reported across studies, with ICS adherence ranging from 40% to 60% [4], [5], [6], [7].

The degree of benefit of an appropriate prescription to patients will, to a large extent, depend on how closely patients follow the instructions for use.

Several theoretical models have been developed to explain illness-related behavior, including adherence to treatment. These emphasize the importance of “commonsensical” beliefs about the illness and perceptions of personal capacity to follow treatment recommendations [8], [9]. When applied to treatment adherence, the explanatory power of theoretical models is likely to be enhanced by considering patients' representations of treatment and adherence [10], [11]. To operationalize these treatment representations in relation to medication, specific and general beliefs about medicines are considered [12]. To describe the salient beliefs influencing patients' decisions about taking medicines, Horne and Weinman [11] developed the Necessity–Concerns Framework. This suggests that patients' motivation to start and persist with medication is influenced by the way in which they judge their personal need for the treatment relative to their concerns about potential adverse effects [11]. Deciding that a treatment is necessary is a process of balancing the pros and the cons, influenced by the patients' perceptions of their illness and symptoms experienced relative to expectations [15]. Specific concerns about prescribed medicines are related to more general beliefs (or social representations) about pharmaceuticals as a class of treatment, as well as to the experience or fear of side effects [12]. Adherence behavior is more closely related to specific beliefs than to general beliefs [12].

Both specific and general medication beliefs can be assessed using the Beliefs about Medicines Questionnaire (BMQ) [12]. The BMQ has been validated in patients with various chronic diseases, including asthma [12], [13]. Necessity beliefs and concerns, as assessed by the BMQ (the Necessity–Concerns Framework), have been shown to explain nonadherence across a range of illnesses, including rheumatoid arthritis [13], heart failure [14], and asthma [15], and associations have been found uninfluenced by the number of medications used [16].

Patients' self-report is the most common method of assessment used in psychological research, but it is subject to self-presentational and recall biases [11]. It has been applied mostly as a convenient “spot-check” estimate of adherence behavior to grade patients according to their “relative standing on the adherence dimension” [11].

A method that is widely applied in epidemiology to assess adherence is the use of pharmacy records, which have shown to be a reliable source of current drug exposure as estimated in a home inventory [17], [18].

Pharmacy records assist in evaluating patients' medication-taking behavior [19], [20] and are informative on the proportion of patients who are most likely to be nonadherent as a consequence of insufficient filling of prescriptions [21].

There is, in addition to self-reported measures, a need for the investigation of objective indicators of medication use in relation to patients' beliefs about medicines in order to identify and, in the future, effectively address barriers to effective self-management. Therefore, the aim of this study is to determine whether patients' beliefs correlate with objective indicators of ICS use retrieved from pharmacy dispensing records in a community population.

Section snippets

Patients

A cross-sectional study, in which patients aged 18–45 years who were filling ICS prescriptions in 11 pharmacies in The Netherlands were selected, was performed. These patients' automated prescription records from 1 January 2001 until 28 February 2005 were available. Patients who filled at least two ICS prescriptions, of which at least one was filled in the 6 months before 1 March 2005, were eligible for inclusion in the study. Since the majority of patients in The Netherlands are registered at

Participants

Eight hundred three patients aged 18–45 years who filled at least two prescriptions for ICS during the past 5 years were eligible to participate in the study. Of these patients, a random sample was taken per pharmacy. From 458 patients who were sent a questionnaire, 238 patients (51.1%) responded. After the exclusion of 1.1% of questionnaires with >10% missing responses, the questionnaires of 233 patients (50.9%) were analyzed (Fig. 1).

Medication beliefs

Almost half of the sample (46.4%) had doubts about the

Discussion

In addition to previous studies, we have shown that not only self-reported adherence but also adherence by prescription-refill records correlated with patients' beliefs about ICS (necessity and concerns). Our findings show that the Necessity–Concerns Framework provides an insight into not only patients' intentions to take medication but also their actual medication-taking behavior. Nonadherence to ICS, as assessed using pharmacy records, was associated with patients' evaluation of their

Acknowledgments

The authors wish to acknowledge the pharmacies, their patients who participated, and M. Koppelaar, BSc, for their time and effort in contributing to data collection.

The SIR Institute for Pharmacy Practice and Policy received unrestricted support from GlaxoSmithKline (Zeist, The Netherlands) for the conduct of this study.

References (38)

  • EA Halm et al.

    No symptoms, no asthma: the acute episodic disease belief is associated with poor self-management among inner-city adults with persistent asthma

    Chest

    (2006)
  • S Suissa et al.

    Regular use of inhaled corticosteroids and the long term prevention of hospitalisation for asthma

    Thorax

    (2002)
  • GINA

    Workshop report, Global strategy for asthma management and prevention

    (October 2006)
  • CS Rand et al.

    Long-term metered-dose inhaler adherence in a clinical trial. The Lung Health Study Research Group

    Am J Respir Crit Care Med

    (1995)
  • H Leventhal et al.

    Self regulation, health and behaviour: a perceptual–cognitive approach

    Psychol Health

    (1998)
  • A Bandura

    Social foundations of thought and action: a social cognitive theory

    (1986)
  • R Horne

    Treatment perceptions and self regulation

  • R Horne et al.

    Self-regulation and self-management in asthma: exploring the role of illness perceptions and treatments beliefs in explaining non-adherence to preventer medication

    Psychol Health

    (2002)
  • R Horne et al.

    The Beliefs about Medicines Questionnaire: the development and evaluation of a new method for assessing the cognitive representation of medication

    Psychol Health

    (1999)
  • Cited by (0)

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