Authors
- Roseleur, Jacqueline
ABSTRACT
Objective: The objective of this review is to map the evidence on the use of behavioral economic insights to improve medication adherence in adults with chronic conditions.
Introduction: Medication non-adherence is a barrier to effectively managing chronic conditions, leading to poorer patient outcomes and placing an additional financial burden on healthcare systems. As the population ages and the prevalence of chronic disease increases, new ways to influence patient behavior are needed. Approaches that use insights from behavioral economics may help improve medication adherence, thus reducing morbidity, mortality and financial costs of unmanaged chronic diseases.
Inclusion criteria: Eligible studies will include adults taking medication for a chronic condition. All interventions relevant to high-income settings using insights from behavioral economics to improve medication adherence in adults will be considered. Contexts may include, but are not limited to, primary health care, corporate wellness programs and health insurance schemes. Any study design published in English will be considered. Studies in facilities where medication is administered to patients will be excluded.
Methods: PubMed, Embase, Scopus, PsycINFO, EconLit and CINAHL will be searched from database inception to present. Gray literature will be searched using Google Scholar, OpenGrey and the Grey Literature Report. One reviewer will review titles, and then two reviewers will independently review abstracts to identify eligible studies. One reviewer will extract data on study characteristics, study design and study outcomes. A second reviewer will validate 25% of the extracted information. The results of the data extraction will be presented in a table, and a narrative summary will be presented.
Article Content
Introduction
Medication non-adherence has been identified as a major barrier to effectively managing chronic conditions.1 The consequences of non-adherence include poorer outcomes for patients,2 higher rates of hospitalization3,4 and increased mortality,5 even for patients taking only placebo.6 This increase in morbidity and mortality due to non-adherence places an additional financial burden on healthcare systems.7
Non-adherence may exist at different stages of the treatment continuum. Patients may not initiate treatment by failing to fill their prescription; they may fail to implement the correct dosage by either missing doses or taking more or less than the prescribed dose; or they may discontinue treatment early.8 Non-adherent behavior can be intentional or unintentional.9,10 Intentional non-adherence involves an active decision by the patient to either alter doses or not take the medication at all, whereas unintentional non-adherence includes more passive actions, such as forgetting to take medication or being unable to follow instructions due to cognitive or physical limitations.9,10 Patients can exhibit both intentional and unintentional behaviors simultaneously.11
Rates of primary non-adherence, which is defined as the failure to initiate treatment, are estimated between 6% and 35%.12-19 This means that up to one-third of patients do not fill their first prescription. The main reasons for lack of initiation include perceptions around need, affordability and concerns about the risks and benefits of medication.20 Even if patients fill their first prescription, a Canadian study found that between 6% and 14% of patients taking statins failed to fill their second prescription.21 Within one year, approximately 50% of patients prescribed antihypertensive therapy were non-adherent,22 and by 24 months, 43% of patients with cardiovascular disease were non-adherent.23
Several reviews have investigated barriers to medication adherence at the patient, provider and health system levels.24-29 In addition, there are extensive literature reviews on interventions to improve medication adherence in general30-32; for specific diseases or risk factors, such as hypertension,33-37 diabetes38-41 and cardiovascular disease42-46; and for specific target groups, such as older adults,47-49 patients with adherence problems50 and underrepresented adults.51,52 A systematic review from 2013 on the cost-effectiveness of medication adherence interventions was able to identify only 14 eligible studies.53 The findings from these studies were mixed, with only four studies showing incremental cost-effectiveness ratios below stated willingness-to-pay thresholds. The authors also found that the reason many of the studies were unable to show cost-effectiveness was that the interventions were ineffective at improving medication adherence.
A potentially cost-effective addition to medication adherence interventions could come from behavioral economic insights. Whereas neoclassical economics assumes that individuals are rational and make decisions based on consistent preferences and sufficient information, behavioral economics identifies a number of systematic cognitive biases that influence individual decision making and behaviors.54 One such bias, present bias, disproportionately weights present costs and benefits relative to future costs and benefits.55 This can be illustrated in patients with asymptomatic disorders, such as hypertension, requiring long-term adherence to medication. The financial costs and the inconvenience of taking medication is in the present and is weighted more than the potential benefits of the medication, which are often far in the future.54 Interventions using financial incentives to offset the immediate costs of inconvenient or onerous behaviors have been used to increase physical activity56-60 and improve medication adherence.61,62 One study aimed to increase physical activity by offering financial incentives through a lottery system.60 The financial incentives offset the immediate costs of exercising, and the lottery system took advantage of another behavioral economic concept, prospect theory, to improve the impact of the financial incentives. Prospect theory states that people tend to overweigh small probabilities when deciding between alternative options that involve uncertainty and risk.63 Another bias associated with prospect theory, loss aversion, describes the concept where individuals experience greater pain when losing something than pleasure from gaining the same thing.64 Recognition of this bias has been used in interventions to increase weight loss, at least in the short term.59,65 One study included a deposit contract as one of the three weight loss plans being tested.65 The deposit contract required participants to invest their own money, which was forfeited if they failed to meet their weight loss goals.
Many of the therapies for managing chronic diseases are highly effective. For these therapies to achieve their potential impact, especially as the population ages and the prevalence of chronic disease increases, exploring new ways to influence patient behavior is needed.66,67 Approaches using insights from behavioral economics may provide new opportunities to improve medication adherence, thereby reducing the burden, both in terms of morbidity and mortality, and additional healthcare costs of unmanaged chronic diseases. A scoping review on the use of behavioral economic interventions for the prevention and treatment of type 2 diabetes found 15 studies that used one of three types of behavioral economic interventions: financial incentives, choice architecture adjustments and commitments devices.68 The authors concluded that these studies showed potential for improving patient behaviors in relation to diabetes. A broader perspective will be taken in this study, including additional behavioral economic concepts and a wider range of chronic conditions requiring long-term medication adherence. The objective of this review is to map the available evidence to provide an overview of the use of behavioral economic insights to improve medication adherence in adults with chronic conditions in a high-income setting.
A preliminary search was conducted in August 2018 for scoping and systematic reviews on this topic in the following databases: JBI Database of Systematic Reviews and Implementation Reports, Cochrane Database of Systematic Reviews, PubMed, Epistemonikos and the Cumulative Index to Nursing and Allied Health Literature (CINAHL). No similar studies were found.
Review questions
The four research questions, which will be used to inform the development of an intervention in a high-income setting, are as follows:
i. Which behavioral economic insights have been investigated to improve medication adherence for adult patients with chronic conditions?
ii. Which patient populations, outcomes and diseases have been studied?
iii. Which research methods have been used in the studies on this subject?
iv. How effective are interventions that draw on behavioral economic insights at improving medication adherence for adult patients with chronic conditions?
Inclusion criteria
As a scoping review takes a broader view of an issue, the population, concept and context framework has been used.69
Population
Studies that include adults taking medication for the treatment of a chronic condition will be considered for this scoping review. Studies in hospitals, prisons, aged-care homes and other facilities where medication is administered to patients will be excluded. Chronic conditions will include both diseases and risk factors requiring long-term medication adherence, including cardiovascular diseases, hypertension, type 2 diabetes mellitus, human immunodeficiency virus and chronic kidney disease. Mental health conditions will also be included.
Concept
All interventions relevant to high-income settings using insights from behavioral economics to improve medication adherence in adults will be considered, such as interventions to address decision errors relating to present bias, prospect theory (poor understanding of probabilities), loss aversion and social influences/norms.
Context
All relevant high-income contexts will be considered for inclusion. These may include, but are not limited to, primary health care (e.g. general practice facilities, community clinics, pharmacies), companies with corporate wellness programs and health insurance schemes.
Types of studies
Any study designs published in English, including experimental, quasi-experimental and non-experimental studies will be considered for inclusion. No limits will be placed on the source of evidence, as this approach will lead to greater sensitivity in the search, which is preferred for scoping reviews.70 Because this is a scoping review, all study types including observational studies, pilot studies and randomized trials will be included. Opinion papers and letters will be excluded.
Methods
Search strategy
The purpose of scoping reviews is to provide a broad overview of a particular area of interest, identifying the key concepts and research gaps, and summarizing and disseminating research findings.71 Because this study aims to describe a broad range of patients, diseases, research methodologies and behavioral economic interventions to improve medication adherence for chronic conditions, a scoping review is an appropriate methodology.69 The JBI Reviewer's Manual will be used to conduct this study.70 As the development of the PRISMA statement for scoping reviews (PRISMA-ScR) is still underway, the PRISMA statement for reporting healthcare interventions will be used.72,73
Information sources
The research team includes a general practice expert (NS) who provided advice on the chronic conditions to be included. Following this, a three-step search strategy was undertaken.74 After an initial search of two databases, the text words and index terms of relevant articles were identified and included in the final search strategy. This search strategy was peer reviewed by an information specialist using the Peer Review of Electronic Search Strategies (PRESS) checklist.75 The following databases will be searched for citations published in English: PubMed, Embase, Scopus, PsycINFO, EconLit and CINAHL from database inception to present. Gray literature will be searched using Google Scholar, OpenGrey and the Grey Literature Report. Forward and backward citation searching of relevant articles will be done. No time limit will be placed on the search strategy. The final search strategy for PubMed is presented in Appendix I. Search strategies for the other databases are available from the corresponding author.
Study selection
The citations will be imported into EndNote V8.2 (Clarivate Analytics, PA, USA), and duplicates will be removed. Duplicates not detected by EndNote will be removed manually. The remaining citations will be imported into Rayyan (Qatar Computing Research Institute, Doha, Qatar). Because many of the behavioral economic terms have multiple uses in other research areas and a large number of results is expected, one reviewer will review titles only. Thereafter, two reviewers will independently review abstracts using a questionnaire with inclusion criteria to identify eligible studies. The full-text articles will be reviewed by two reviewers for articles where the title and abstract contain insufficient information to determine eligibility. If the full-text article is still unclear on the study eligibility criteria, study authors will be contacted for further information. Where disagreements exist among reviewers, the article will be discussed between the two reviewers to reach consensus. If there is continued disagreement, a third reviewer will be requested to make a final decision. The reasons for excluding studies at the full-text level will be recorded and reported in the review.
Data extraction
One reviewer will extract data on study characteristics, study design and study outcomes using Microsoft Excel (Redmond, Washington, USA). The extraction form will be trialed on a sample of five studies to ensure all relevant details are captured. Study characteristics will include authorship, the year the study was conducted, year and journal of publication, funding source, geographical region and type of article. Study design will include type of study, aim of the study, type of behavioral economic insight used, intervention, comparator, study population, sample size, patient care setting, patient characteristics, disease, type of medication, duration of the intervention, follow-up period and statistical methods used. Study outcomes will include how medication adherence was measured and the key findings of the study. A second reviewer will validate 25% of the extracted information. Any disagreements will be resolved through discussion until consensus is reached.
Data presentation
The results of the data extraction will be presented in a table that outlines the first author, geographical location, year of publication, study population, study design, type(s) of interventions, comparator(s), participant characteristics (average age, race, ethnicity and sex) and characteristics of the intervention (strategy, details of the intervention, duration and primary outcomes). Descriptive statistics will be used to provide a summary of the characteristics of the studies, including the year of publication, geographical locations, funding sources, duration of the study, disease and setting of the study. These categorical data will be summarized using percentages and frequencies. A narrative summary of the studies will be prepared considering the nature of the intervention, the population, study design features and the study results. In addition, the narrative summary will also consider the nature of the disease area targeted (i.e. physical or mental condition, symptomatic or asymptomatic, and the proximity or risk of adverse consequences).
Acknowledgments
The authors thank Vikki Langton from the University of Adelaide Library for peer reviewing the literature search strategy.
Appendix I: Search strategy for PubMed
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