Approach to enhance medication adherence

development and validation of a survey tool (OMAS-37) and subsequent use towards a mobile application targeting users of antidepressants (ADA

Sammendrag

Background: Adhering to prescribed medication regimens significantly influences patient outcomes. Despite this, rates of patients’ medication adherence vary widely, underscoring the importance for clinical health professionals and others to focus on adherence-enhancing approaches. To ensure the applicability and relevance of such approaches, it is crucial to understand the individual patient/patient groups’ reasons for non-adherence. Self-reporting is a commonly used method for assessing adherence. A challenge has been to identify a tool that encompasses not only commonly measured medication-taking behaviour but also barriers to adherence, in addition to beliefs about disease and medication. These are all important aspects to be aware of when designing interventions to improve adherence. Considering that 95% of the Norwegian population owns a smartphone and given that the literature generally demonstrates a positive correlation between the use of mobile-based interventions and adherence, the potential for such interventions to enhance adherence in a Norwegian patient group could be considerable. Aims: The overall aim of the thesis was to devise an approach to enhance patients’ medication adherence. First, we aimed to develop and validate a self-reporting adherence survey tool that assesses adherence and quantifies causes of non-adherence arising from medication-taking behaviour, barriers to adherence, and beliefs about disease and medication. Second, we aimed to utilise the validated survey tool to assess adherence in a general population to identify a patient group that could potentially benefit from an adherence intervention, as well as identifying the main causes of non-adherence in this patient group. Third, we aimed to develop a mobile adherence application (app) for the identified patient group, with content based on their identified main causes of non-adherence. The validated survey tool was then utilised to assess the effects of the app on adherence within this patient group. Methods: Development and validation of the survey tool were conducted by literature search and assessment of psychometric properties of content, construct, reliability, and feasibility. The survey tool comprised various causes of non-adherence. Respondents assigned scores to each cause of non-adherence using a Likert scale. Increasing non-adherence scores indicate reduced adherence. Descriptive statistics were used to quantify non-adherence scores for the total sample, and for 24 medical-condition patient groups. The main causes of non-adherence were also quantified for the total sample and three of the medical-condition patient groups: the Cardiovascular Diseases (CVD) group, the Mental Health Disorders (MHD) group and the Pain group. Descriptive statistics and the non-parametric Wilcoxon Signed Rank Test were used to assess the effect of the intervention on adherence in a single group pre-post app access design. Data collections were gathered using online surveys. For the initial data collection (validate survey tool and identify patient group for app), respondents were primarily recruited through SM-platforms. For the secondary collection (pre-app access), recruitment was conducted via both SM-platforms and online newspapers. Main findings: The survey tool, named OMAS-37 (OsloMet Adherence-to-Medication Survey tool), ultimately encompassed 37 causes of non-adherence, and proved to be a valid and reliable instrument, with a Cronbach's alpha of 0.91. Following an evaluation of respondent figures, nonadherence scores and potential advantages for different patient cohorts, the MHD group was chosen as the target for the adherence app, and the main causes of non-adherence for this patient demographic were identified. To provide precise guidance in the app, a selection was made to narrow down the diverse medication usage within the MHD group to specifically target users of Selective Serotonin Reuptake Inhibitors (SSRIs) and Serotonin and Norepinephrine Reuptake Inhibitors (SNRIs). The app was named ADA (AntiDepressants App) and the main content was built on the five primary causes of non-adherence identified within the MHD-group. One hundred and three SSRI/SNRI users responded to the Pre-access survey and were given access to ADA. Forty-two of the 103 SSRI/SNRI users, with a median age of 26 (IQR 20-37) and 93% identifying as women, responded to the Post-access survey after having accessed ADA for a two-month period, during which they used the same SSRI/SNRI. Access to ADA led to a statistically significant (p<0.01) enhanced adherence for the SSRI/SNRI users with a medium effect size (r=0.39). Conclusion: In this thesis we present a validated survey tool, OMAS-37, to assess adherence and quantify the causes of non-adherence across a variety of patient groups. It is also demonstrated that customising an app, based on the main causes of non-adherence for SSRI/SNRI users, had a statistically significant positive impact on the adherence of these users. This underscores the potential adherence-enhancing approach for clinical health professionals and others to initially use OMAS-37 to pinpoint the causes of non-adherence within a patient group and subsequently utilise these causes to customise adherence-improving interventions for the same group.