A new taxonomy for describing and defining adherence to medications

Adherence to phosphate binders in hemodialysis patients: prevalence and determinants

BACKGROUND

Phosphate control is a crucial treatment goal in end-stage renal disease, but poor patient adherence to phosphate binder therapy remains a challenge. This study aimed to estimate the extent of phosphate binder adherence in hemodialysis patients and to identify potential determinants.

METHODS

Phosphate binder adherence was measured blindly in 135 hemodialysis patients for 2 months using the medication event monitoring system. Patient data, gathered at inclusion through medical records, ad hoc questionnaires and the short form (SF)-36 health survey, included: (1) demographics, (2) perceived side-effects, belief in benefit, self-reported adherence to the therapy, (3) knowledge about phosphate binder therapy, (4) social support, and (5) quality of life (SF-36). Phosphatemia data was collected from charts. 'Being adherent' was defined as missing <1 total daily dose/week and 'being totally adherent' as missing <1 total daily dose/week, every week.

RESULTS

Mean age of patients was 67 years and 64 % of the sample was male. Over the 2 months, 78 % of the prescribed doses were taken. Every week, about half of patients were adherent. Over the entire 8-week period, 22 % of patients were totally adherent. Mean phosphatemia levels were 0.55 mg/dl lower in adherent than nonadherent patients (4.76 vs. 5.31 mg/dl). Determinants for being totally adherent were living with a partner, higher social support (both were interrelated) and higher physical quality of life. Experiencing intake-related inconvenience negatively affected adherence. The social support and quality of life physical score explained 26 % of the variance in adherence.

CONCLUSIONS

Phosphate binder nonadherence remains a major problem. Interventions should aim, at least, to improve social support. With few associated factors found and yet low adherence, an individualized approach seems indicated.

The non-interventional BonViva Intravenous Versus Alendronate (VIVA) study: real-world adherence and persistence to medication, efficacy, and safety, in patients with postmenopausal osteoporosis

Adherence and persistence to oral bisphosphonates in women with postmenopausal osteoporosis is suboptimal. In this study, patients were treated with either oral or intravenous bisphosphonates. The increased adherence and persistence observed in patients receiving intravenous medication compared with those receiving oral medication may improve health outcomes.

INTRODUCTION

Poor adherence and persistence to oral medication are often observed in women with postmenopausal osteoporosis (PMO). The purpose of the non-interventional BonViva Intravenous Versus Alendronate (VIVA) study was to determine whether, in a real-world setting, (1) increased adherence and persistence to medication would be observed in women with PMO receiving intravenous (i.v.) ibandronate versus oral alendronate, (2) a correlation exists between adherence and persistence to medication and drug efficacy, and (3) any unexpected adverse events/serious adverse events (AEs/SAEs) may occur.

METHODS

The study was conducted in 632 centers in Germany. A total of 6,064 females with PMO were enrolled and recruited into one of two treatment arms: quarterly i.v. administration of 3 mg ibandronate or weekly oral medication of 70 mg alendronate, for 12 months. At the end of the study, adherence and persistence to medication, new osteoporotic fractures, mobility, use of analgesics, and AEs/SAEs were determined.

RESULTS

Greater adherence and persistence to medication were observed in the ibandronate treatment arm compared with the alendronate treatment arm. Although there was no significant difference in the number of patients with new vertebral, hip, or forearm fractures between treatment arms, a significantly greater increase in mobility and decrease in the use of analgesics were reported in the ibandronate treatment arm. No unexpected AEs/SAEs occurred in either arm.

CONCLUSIONS

Adherence and persistence to medication were greater in women with PMO receiving i.v. ibandronate compared with those receiving oral alendronate. This may have led to an increase in mobility and a decrease in pain in these patients.

Pharmacological interventions for ADHD: how do adolescent and adult patient beliefs and attitudes impact treatment adherence?

Adherence to medication can be problematic for patients, especially so for patients with attention deficit hyperactivity disorder (ADHD). Effective medications are available for the treatment of ADHD; however, nonadherence rates for ADHD medication range from 13.2%-64%. The reasons for nonadherence can be complex. This review aims to look at how the beliefs and attitudes of adolescents and adults impact ADHD treatment adherence.

[The importance of adherence to oral therapies in the field of oncology: the example of breast cancer]

Today, over 40 different oral anticancer therapies are available in the French prescription pricing authority dictionary. Adherence to these therapies has become a major issue in the field of oncology. Most of the available research has focused on adherence to hormonal therapy for breast cancer (BC). The objective of this paper is to synthesize current knowledge on adherence and persistence to hormonal therapy for BC. Available studies display significant heterogeneity due to variability in the measurements and data sources used, as well as in the timing of the measurements. Adherence and persistence estimates have recently been summarized in a meta-regression analysis. For tamoxifen, adherence ranges from 79% at one year to 65% at five years, and for Aromatase Inhibitors (AI), from 80% at one year to 72% at five years. Persistence decreases with the increasing duration of treatment: from a high of 86% of patients persistent at 1 year to a low of 53% at five years for tamoxifen, and from 88% to 69% for AI. Some of the modifiable determinants of adherence are directly linked to the patient-physician relation, to information provided during consultations, or to the specialty of the physician involved in the patient follow-up. Non-modifiable determinants, such as age or comorbidities, can be used to identify sub-groups of patients at high risk of non-adherence in order to target interventions. Few trials have been conducted in oncology to evaluate the efficacy of interventions to improve adherence. Adherence directly impacts both the efficacy of treatment and long-term treatment costs. Interventions to improve adherence to oral therapies should be systematically promoted in oncology. Improving adherence should be considered a priority in the field, lest physicians continue writing inefficient prescriptions for highly efficacious treatments.

Daytime sleepiness in renal transplant recipients is associated with immunosuppressive non-adherence: a cross-sectional, multi-center study

BACKGROUND

The aims of this study were to determine the prevalence of immunosuppressive non-adherence (NA) in renal transplant patients and describe whether the degree of daytime sleepiness (DS) and depressive symptomatology are associated with immunosuppressive NA.

METHODS

Using a cross-sectional design, 926 home-dwelling renal transplant recipients who were transplanted at one of three Swiss transplant centers provided data by self-report. The Basel Assessment of Adherence Scale for immunosuppressive was used to measure the following: taking, timing, and overall NA to immunosuppressive medication. DS was assessed with the Epworth Sleepiness Scale (ESS) (cut-off ≥6 for DS) and the Swiss Transplant Cohort Study DS item (cut-off ≥4 for DS), and depressive symptomatology was assessed with the Depression, Anxiety, and Stress Scale (cut-off>10). An ordinal logistical regression model was applied for statistical analysis.

RESULTS

The prevalence of the ESS-DS was 51%. NA for taking, timing, and the median overall NA level assessed by 0-100% visual analog scale (VAS) was 16%, 42%, and 0%, respectively. Based on the multivariate analysis, DS was significantly associated (p < 0.001) with taking (1.08 [1.04-1.13]), timing (1.07 [1.03-1.10]), and overall NA (1.09 [1.05-1.13]). Very similar results were found for the Swiss Transplant Cohort Study DS item.

CONCLUSION

DS is associated with immunosuppressive medication NA in renal transplant recipients. Admittedly, the association's strength is limited.

Interventions to improve osteoporosis medication adherence and persistence: a systematic review and literature appraisal by the ISPOR Medication Adherence & Persistence Special Interest Group

This study aims to systematically review, critically appraise and identify from the published literature, the most effective interventions to improve medication adherence in osteoporosis. A literature search using Medline, EMBASE, Cochrane library, and Cumulative Index to Nursing and Allied Health Literature was undertaken to identify prospective studies published between January 1, 1999 and June 30, 2012. We included studies on adult users of osteoporosis medications that tested a patient adherence intervention (e.g., patient education, intensified patient care, different dosing regimens) and reported quantitative results of adherence. The Delphi list was modified to assess the quality of studies. Of 113 articles identified, 20 studies fulfilled the inclusion criteria. The most frequent intervention was education (n = 11) followed by monitoring/supervision (n = 4), drug regimens (n = 2), drug regimens and patient support (n = 1), pharmacist intervention (n = 1), and electronic prescription (n = 1). Although patient education improved medication adherence in four studies, two large-scale randomized studies reported no benefits. Simplification of dosing regimens (with and without patient support program) was found to have a significant clinical impact on medication adherence and persistence. Monitoring/supervision showed no impact on medication persistence while electronic prescription and pharmacist intervention increased medication adherence or persistence. In conclusion, this review found that simplification of dosing regimens, decision aids, electronic prescription, or patient education may help to improve adherence or persistence to osteoporosis medications. We identified wide variation of quality of studies in the osteoporosis area. The efficacy of patient education was variable across studies, while monitoring/supervision does not seem an effective way to enhance medication adherence or persistence.

Persistence of antihypertensive drug use in German primary care: a follow-up study based on pharmacy claims data

PURPOSE

To study drug persistence for antihypertensive treatment considering typical patient behaviour including extended drug holidays or irregular repeat prescriptions.

METHODS

We used prescription data from a German statutory health insurance to follow up patients for 4 years. Medication persistence was defined as the continued use of a specific drug class, therapy persistence as the continued use of any antihypertensive drug. We applied 2 different interval criteria within which a repeat prescription had to be issued: 180 and 360 days.

RESULTS

A total of 9,513 patients started an antihypertensive therapy between 2006 and 2008. Applying the 180-day (360-day) interval criterion, 28 % (66 %) of the patients starting therapy with a beta-blocker were still medication-persistent after 4 years. The rates were similar for angiotensin-II receptor blockers (ARBs; 30 % and 69 % respectively) or angiotensin-converting enzyme (ACE) inhibitors (28 % and 61 % respectively). Looking at therapy persistence, these rates were 44 % (79 %) when an ACE inhibitor was the initial drug, 46 % (82 %) for ARBs. On average, even of those who were defined as therapeutically persistent with the 360 days criterion, half received a repeat prescription within 96 days, three quarters within 131 days-with a median supply of 1.2 units per day and 1.25 defined daily doses.

CONCLUSION

By applying more patient-orientated criteria, we found that many patients were therapy-persistent and received a prescription at the appropriate time. Therapy persistence was nearly independent of the initial agent; thus, drug persistence may not be an argument in favour of choosing a certain drug as a first-line option.

Missing signposts on the roadmap to quality: a call to improve medication adherence indicators in data collection for population research

PURPOSE

Poor adherence to prescribed medicines is associated with increased rates of poor outcomes, including hospitalization, serious adverse events, and death, and is also associated with increased healthcare costs. However, current approaches to evaluation of medication adherence using real-world electronic health records (EHRs) or claims data may miss critical opportunities for data capture and fall short in modeling and representing the full complexity of the healthcare environment. We sought to explore a framework for understanding and improving data capture for medication adherence in a population-based intervention in four U.S. counties.

APPROACH

We posited that application of a data model and a process matrix when designing data collection for medication adherence would improve identification of variables and data accessibility, and could support future research on medication-taking behaviors. We then constructed a use case in which data related to medication adherence would be leveraged to support improved healthcare quality, clinical outcomes, and efficiency of healthcare delivery in a population-based intervention for persons with diabetes. Because EHRs in use at participating sites were deemed incapable of supplying the needed data, we applied a taxonomic approach to identify and define variables of interest. We then applied a process matrix methodology, in which we identified key research goals and chose optimal data domains and their respective data elements, to instantiate the resulting data model.

CONCLUSIONS

Combining a taxonomic approach with a process matrix methodology may afford significant benefits when designing data collection for clinical and population-based research in the arena of medication adherence. Such an approach can effectively depict complex real-world concepts and domains by "mapping" the relationships between disparate contributors to medication adherence and describing their relative contributions to the shared goals of improved healthcare quality, outcomes, and cost.

Impact of diabetes mellitus on clinical parameters and treatment outcomes of newly diagnosed pulmonary tuberculosis patients in Thailand

BACKGROUND

To assess the clinical and laboratory parameters, response to therapy and development of antituberculosis (TB) drug resistance in pulmonary TB (PTB) patients with diabetes mellitus (DM) and without DM.

METHODS

Using a prospective design, 227 of 310 new cases of culture-positive PTB diagnosed at the Queen Savang Vadhana Memorial Hospital and the Chonburi Hospital between April 2010 and July 2012 that met the study criteria were selected. Data regarding clinical and laboratory parameters, drug susceptibility and treatment outcomes were compared between PTB patients with DM and those without DM. To control for age, the patients were stratified into two age groups (< 50 and ≥ 50 years) and their data were analysed.

RESULTS

Of the 227 patients, 37 (16.3%) had DM, of which 26 (70.3%) had been diagnosed with DM prior to PTB diagnosis and 11 (29.7%) had developed DM at PTB diagnosis. After controlling for age, no significant differences were found between the two groups regarding mycobacterium burden, sputum-culture conversion rate, evidence of multidrug-resistant tuberculosis, frequency of adverse drug events from anti-TB medications, treatment outcomes and relapse rate. The presenting symptoms of anorexia (p = 0.050) and haemoptysis (p = 0.036) were observed significantly more frequently in PTB patients with DM, while the presenting symptom of cough was observed significantly more frequently in PTB patients without DM (p = 0.047).

CONCLUSIONS

Plasma glucose levels should be monitored in all newly diagnosed PTB patients and a similar treatment regimen should be prescribed to PTB patients with DM and those without DM in high TB-burden countries.

Long-term adherence to antimuscarinic therapy in everyday practice: a systematic review

PURPOSE

Antimuscarinic drug treatment is known to have side effects and, consequently, poor adherence in therapeutic regimens. In this systematic review we study the long-term (greater than 6 months) adherence to antimuscarinic drugs in daily clinical practice, and identify factors contributing to poor adherence and persistence.

MATERIALS AND METHODS

This systematic review was conducted according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. A literature search was performed using PubMed® and Embase™ using synonyms for incontinence, overactive bladder and antimuscarinics combined with synonyms for medication adherence. We chose to include only pharmaceutical database studies (using prescription/insurance claim data) and patient self-report studies, using established pharmacoepidemiological parameters such as persistence rate and medication possession rate.

RESULTS

A total of 1,245 titles were screened, of which 102 abstracts were assessed. Fourteen studies were ultimately included, comprising 190,279 unique patients (mean age 69.5 years). Regardless of which specific antimuscarinic drug is studied, persistence rates are usually poor. Considering all drugs together, median persistence rates were 12.0% to 39.4% (with an outlier of 75.5%) at 12 months, 8.0% to 15.0% at 18 months and 6.0% to 12.0% at 24 months. At 36 months persistence rates ranged from 0.0% (darifenacin) to 16.0% (trospium). Mean reported medication possession rates were also low, with a mean of 0.37 at 12 months. Risk factors for discontinuation were identified, with the most important being younger age group, use of oxybutynin and use of immediate release formulations.

CONCLUSIONS

Improvement in adherence and persistence with antimuscarinic medication should be an important goal in the development of new drugs for overactive bladder and urinary incontinence.

What the newspapers say about medication adherence: a content analysis

Background

This study investigates the coverage of adherence to medicine by the UK and US newsprint media. Adherence to medicine is recognised as an important issue facing healthcare professionals and the newsprint media is a key source of health information, however, little is known about newspaper coverage of medication adherence.

Methods

A search of the newspaper database Nexis®UK from 2004–2011 was performed. Content analysis of newspaper articles which referenced medication adherence from the twelve highest circulating UK and US daily newspapers and their Sunday equivalents was carried out. A second researcher coded a 15% sample of newspaper articles to establish the inter-rater reliability of coding.

Results

Searches of newspaper coverage of medication adherence in the UK and US yielded 181 relevant articles for each country. There was a large increase in the number of scientific articles on medication adherence in PubMed® over the study period, however, this was not reflected in the frequency of newspaper articles published on medication adherence. UK newspaper articles were significantly more likely to report the benefits of adherence (p = 0.005), whereas US newspaper articles were significantly more likely to report adherence issues in the elderly population (p = 0.004) and adherence associated with diseases of the central nervous system (p = 0.046). The most commonly reported barriers to adherence were patient factors e.g. poor memory, beliefs and age, whereas, the most commonly reported facilitators to adherence were medication factors including simplified regimens, shorter treatment duration and combination tablets. HIV/AIDS was the single most frequently cited disease (reported in 20% of newspaper articles). Poor quality reporting of medication adherence was identified in 62% of newspaper articles.

Conclusion

Adherence is not well covered in the newspaper media despite a significant presence in the medical literature. The mass media have the potential to help educate and shape the public’s knowledge regarding the importance of medication adherence; this potential is not being realised at present.

Standardizing terminology and definitions of medication adherence and persistence in research employing electronic databases

OBJECTIVE

To propose a unifying set of definitions for prescription adherence research utilizing electronic health record prescribing databases, prescription dispensing databases, and pharmacy claims databases and to provide a conceptual framework to operationalize these definitions consistently across studies.

METHODS

We reviewed recent literature to identify definitions in electronic database studies of prescription-filling patterns for chronic oral medications. We then develop a conceptual model and propose standardized terminology and definitions to describe prescription-filling behavior from electronic databases.

RESULTS

The conceptual model we propose defines 2 separate constructs: medication adherence and persistence. We define primary and secondary adherence as distinct subtypes of adherence. Metrics for estimating secondary adherence are discussed and critiqued, including a newer metric (New Prescription Medication Gap measure) that enables estimation of both primary and secondary adherence.

DISCUSSION

Terminology currently used in prescription adherence research employing electronic databases lacks consistency. We propose a clear, consistent, broadly applicable conceptual model and terminology for such studies. The model and definitions facilitate research utilizing electronic medication prescribing, dispensing, and/or claims databases and encompasses the entire continuum of prescription-filling behavior.

CONCLUSION

Employing conceptually clear and consistent terminology to define medication adherence and persistence will facilitate future comparative effectiveness research and meta-analytic studies that utilize electronic prescription and dispensing records.

Medication nonadherence and psychiatry

PURPOSE OF REVIEW

Nonadherence to appropriately prescribed medication for psychiatric disorders prevents patients from realizing the full benefits of their treatment and negatively impacts on individuals, their families and the healthcare system. Understanding and reducing nonadherence is therefore a key challenge to quality care for patients with psychiatric disorders. This review highlights findings regarding the prevalence and consequence of nonadherence, barriers to adherence and new intervention methods from 2012 onwards.

RECENT FINDINGS

Recent research has highlighted that nonadherence is a global challenge for psychiatry and has linked nonadherence to poorer outcomes, including hospital admissions, suicide and mortality. Optimizing medication regimens can reduce nonadherence; however, often a complex interplay of factors affects individuals' motivation and ability to follow their prescription. Psychiatrists can enable patients to develop an accurate model of their illness and treatment and facilitate adherence. However, nonadherence is often a hidden issue within consultations. Novel interventions using new technologies and tailoring techniques may have the potential to reduce nonadherence.

SUMMARY

Nonadherence remains a significant challenge for patients with psychiatric disorders, physicians and healthcare systems. New developments demonstrate the importance of developing tailored interventions to enable patients to overcome perceptual and practical barriers to adherence.

Association between teriparatide adherence and healthcare utilization and costs in real-world US kyphoplasty/vertebroplasty patients

The objective of this study was to examine the association between teriparatide adherence and healthcare utilization and costs in real-world US kyphoplasty/vertebroplasty (KV) patients. Among KV patients newly initiating teriparatide, significantly increased pharmacy costs associated with high teriparatide adherence were offset by significantly lower inpatient utilization and medical costs.

INTRODUCTION

This study seeks to examine the association between teriparatide adherence and healthcare utilization/costs in real-world US KV patients.

METHODS

Identified patients from a large US administrative claims database were aged 50+ with KV from 1/1/2002-12/31/2010 (first observed KV = index). Included individuals had 6+ months of pre-index continuous enrollment and no pre-index teriparatide, cancer, or Paget's disease. Follow-up period for patients initiating teriparatide was ≤36 months post-index. Three teriparatide adherence cohorts were constructed using the proportion of days covered (PDC) during the follow-up period: low (PDC ≤ 0.5), medium (PDC >0.5-≤ 0.8), and high (PDC >0.8). Repeated KV admissions, any inpatient admission, number of inpatient admissions, and per-patient-per-month (PPPM) inpatient, outpatient, pharmacy, and total costs were compared between cohorts. The associations between teriparatide adherence and healthcare utilization/costs were examined using multivariable regression models, adjusting for patient demographics and clinical characteristics.

RESULTS

Included were 1,568 patients (mean age, 75 years; 82% female): 403 (26%) had low adherence, 382 (24%) medium, and 783 (50%) high. After multivariable adjustment, high adherence was significantly associated with the lowest PPPM inpatient (low = $1,287; medium = $1,005; high = $678) and outpatient (low = $1,464; medium = $1,244; high = $1,077) medical costs, but with increased pharmacy costs (low = $752; medium = $1,159; high = $1,616; all P < 0.05), leading to similar total costs (low = $3,344; medium = $3,376; high = $3,351) between cohorts; high adherence was also significantly associated with the lowest odds of repeated KV admission, any inpatient admission, and number of inpatient admissions (all P < 0.05).

CONCLUSIONS

Among KV patients initiating teriparatide, significantly increased pharmacy costs associated with high teriparatide adherence were offset by significantly lower inpatient utilization and medical costs.

Adherence and discontinuation of oral hormonal therapy in patients with hormone receptor positive breast cancer

BACKGROUND

Oral treatment in women with breast cancer has been increasingly used. However, a potentially negative side of oral medication is poor patient adherence and/or discontinuation, which reduces the treatment effectiveness, accelerating progression of the disease and reducing the patient survival rate.

AIM OF THE REVIEW

To compare the rates of adherence and/or discontinuation and the methodologies used to assess these outcomes. It was conducted an integrative review of original articles published from 2000 to 2012, in which their primary outcome was to quantify medication adherence and/or discontinuation of oral hormonal therapy in patients with hormone receptor positive breast cancer.

METHODS

Original studies were searched in the PubMed/MEDLINE, Scopus, Embase and SciELO databases. The Medical Subject Heading was used to define descriptors. The descriptor "breast neoplasms" was used in all combinations. Each of the descriptors "medication adherence" and "patient compliance" were combined with each of the following descriptors "tamoxifen", "aromatase inhibitors", "selective estrogen receptor modulators", or the terms "letrozole", "anastrozole", and "exemestane".

RESULTS

Twenty-four original articles were included. Our study showed a wide range of adherence and discontinuation rates, ranging from 45-95.7 and 12-73 %, respectively. Regarding the methodological development of the selected articles, a high prevalence (87.5 %) of prospective and/or retrospective longitudinal studies was found. In addition, there was a high prevalence of studies using a database (70.8 %). Among some of the studies, it was shown that patient adherence to hormonal therapy gradually reduces, while discontinuation increases during the treatment.

CONCLUSIONS

It was observed a great diversity among rates of adherence and/or discontinuation of hormonal therapy for breast cancer, which may be due to a lack of methodology standardization. Therefore, adequate and validated methods to ensure reliability of the results and allow comparison in the literature are needed. Furthermore, adherence decreases and discontinuation increases over time, suggesting the need for patient continuous education and a pharmacotherapeutic follow up by health professionals to improve these clinical outcomes.

A randomized controlled trial with a Canadian electronic pill dispenser used to measure and improve medication adherence in patients with schizophrenia

Objective: Medication adherence is extremely important in preventing relapse and lowering symptoms in schizophrenic patients. However, estimates show that nearly half of these patients have poor adherence. The Brief Adherence Rating Scale (BARS) seems to be the most reliable tool assessing adherence in schizophrenia and shows that the antipsychotic adherence ratio (AAR) is about 49.5% in schizophrenia. The aim of the study was to test if an electronic pill dispenser named DoPill^® improved AAR of schizophrenic patients. Furthermore, we compared AAR obtained by the DoPill^® and the BARS, in order to verify whether the DoPill^® provides reliable assessment of medication adherence.

Methods: The DoPill^® is a smart pill dispenser that beeps and flashes at the appropriate time of the day. Each of its 28 compartments is covered by a plastic lamina that, when taken off, sends a signal to the pharmacist. Patients were randomized to the DoPill^® or treatment as usual groups for 6 weeks. The BARS was used as a reference measure.

Results: Forty-six percent of patients were deemed to be non-adherent with antipsychotic medication. The mean AAR was 67% after 6 weeks. DoPill^® recorded better AAR than some of those found in the literature and were lower than the BARS estimate we found.

Conclusion: These results suggest that DoPill^® is a valid tool that provides more reliable and objective data for the clinician about their patient’s adherence, than existing assessment tools like the BARS. Furthermore, the device may help patients successfully manage their medication regimen.

Determinants of patient adherence: a review of systematic reviews

PURPOSE

A number of potential determinants of medication non-adherence have been described so far. However, the heterogenic quality of existing publications poses the need for the use of a rigorous methodology in building a list of such determinants. The purpose of this study was a systematic review of current research on determinants of patient adherence on the basis of a recently agreed European consensus taxonomy and terminology.

METHODS

MEDLINE, EMBASE, CINAHL, Cochrane Library, IPA, and PsycINFO were systematically searched for systematic reviews published between 2000/01/01 and 2009/12/31 that provided determinants on non-adherence to medication. The searches were limited to reviews having adherence to medication prescribed by health professionals for outpatient as a major topic.

RESULTS

Fifty-one reviews were included in this review, covering 19 different disease categories. In these reviews, exclusively assessing non-adherence to chronic therapies, 771 individual factor items were identified, of which most were determinants of implementation, and only 47-determinants of persistence with medication. Factors with an unambiguous effect on adherence were further grouped into 8 clusters of socio-economic-related factors, 6 of healthcare team- and system-related factors, 6 of condition-related factors, 6 of therapy-related factors, and 14 of patient-related factors. The lack of standardized definitions and use of poor measurement methods resulted in many inconsistencies.

CONCLUSIONS

This study provides clear evidence that medication non-adherence is affected by multiple determinants. Therefore, the prediction of non-adherence of individual patients is difficult, and suitable measurement and multifaceted interventions may be the most effective answer toward unsatisfactory adherence. The limited number of publications assessing determinants of persistence with medication, and lack of those providing determinants of adherence to short-term treatment identify areas for future research.

Adherence management for patients with cancer taking capecitabine: a prospective two-arm cohort study

OBJECTIVE

To develop and evaluate a multiprofessional modular medication management to assure adherence to capecitabine.

METHODS

The study was conducted as a prospective, multicentred observational cohort study. All participants received pharmaceutical care consisting of oral and written information. Daily adherence was defined as percentage of days with correctly administered capecitabine doses and assessed using medication event monitoring. According to their daily adherence during the first cycle, patients were identified as initially non-adherent (<90% adherence) or adherent (≥90% adherence). Initially non-adherent patients received additional adherence support.

RESULTS

Seventy-three patients with various tumour entities were enrolled, 58 were initially adherent and 15 non-adherent. Median daily adherence of initially non-adherent patients increased from 85.7% to 97.6% during the observation period of six cycles. Throughout all cycles, median daily adherence of initially adherent patients was 100.0%. Daily adherence was not associated with sociodemographic and disease-related factors. No patient was non-persistent.

CONCLUSIONS

An early adherence screening effectively distinguishes between patients adhering and non-adhering to capecitabine. The provision of specific adherence support is associated with enhanced adherence of initially non-adherent patients, whereas initially adherent patients remain adherent for at least six cycles without specific support. Our needs-based approach helps to use available resources for adherence management efficiently.

What are validated self-report adherence scales really measuring?: a systematic review

AIMS

Medication non-adherence is a significant health problem. There are numerous methods for measuring adherence, but no single method performs well on all criteria. The purpose of this systematic review is to (i) identify self-report medication adherence scales that have been correlated with comparison measures of medication-taking behaviour, (ii) assess how these scales measure adherence and (iii) explore how these adherence scales have been validated.

METHODS

Cinahl and PubMed databases were used to search articles written in English on the development or validation of medication adherence scales dating to August 2012. The search terms used were medication adherence, medication non-adherence, medication compliance and names of each scale. Data such as barriers identified and validation comparison measures were extracted and compared.

RESULTS

Sixty articles were included in the review, which consisted of 43 adherence scales. Adherence scales include items that either elicit information regarding the patient's medication-taking behaviour and/or attempts to identify barriers to good medication-taking behaviour or beliefs associated with adherence. The validation strategies employed depended on whether the focus of the scale was to measure medication-taking behaviour or identify barriers or beliefs.

CONCLUSIONS

Supporting patients to be adherent requires information on their medication-taking behaviour, barriers to adherence and beliefs about medicines. Adherence scales have the potential to explore these aspects of adherence, but currently there has been a greater focus on measuring medication-taking behaviour. Selecting the 'right' adherence scale(s) requires consideration of what needs to be measured and how (and in whom) the scale has been validated.

Does the use of an electronic reminder device with or without counseling improve adherence to lipid-lowering treatment? The results of a randomized controlled trial

BACKGROUND

Lipid-lowering treatment with statins has proven to be effective in reducing cardiovascular events and mortality. In daily practice, however, adherence to medication is often low and this compromises the therapeutic effect. The aim of this study was to assess the effectiveness of an electronic reminder device (ERD) with or without counseling to improve refill adherence and persistence for statin treatment in non-adherent patients.

METHODS

A multicenter, community pharmacy-based, randomized controlled trial was conducted in 24 pharmacies in the Netherlands among patients with pre-baseline refill adherence rates between 50 and 80%. Eligible patients aged 65 years or older were randomly assigned to 1 of 3 groups: (1) counseling with an ERD (n = 134), (2) ERD with a written instruction (n = 131), and a (3) control group that received the usual treatment (n = 134).

MAIN OUTCOME MEASURE

refill adherence to statin treatment for a 360-day period after inclusion (PDC360). Patients with a refill rate ≥80% were considered adherent. The effect among subgroups was also assessed.

RESULTS

There were no relevant differences at baseline. In the counseling with ERD group 54 of 130 eligible patients received the counseling with ERD. In the ERD group, 117 of 123 eligible patients received the ERD. The proportions of adherent patients in the counseling with ERD-group (69.2%) and in the ERD group (72.4%) were not higher than in the control group (64.8%). Among women using statins for secondary prevention, more patients were adherent in the ERD group (86.1%) than in the control group (52.6%) (p < 0.005). In men using statins for secondary prevention the ERD was found to have no effect.

CONCLUSION

In this randomized controlled trial, no statistically significant improvement of refill adherence was found if an ERD was used with or without counseling. However, in a subgroup of women using statins for secondary prevention the ERD did improve adherence significantly.

Interventions for improving adherence to ocular hypotensive therapy

BACKGROUND

Poor adherence to therapy is a significant healthcare issue, particularly in patients with chronic disease such as open-angle glaucoma. Treatment failure may necessitate unwarranted changes of medications, increased healthcare expenditure and risk to the patient if surgical intervention is required. Simplifying eye drop regimes, providing adequate information, teaching drop instillation technique and ongoing support according to the patient need may have a positive effect on improving adherence.

OBJECTIVES

To summarise the effects of interventions for improving adherence to ocular hypotensive therapy in people with ocular hypertension (OHT) or glaucoma.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2012, Issue 6), MEDLINE (June 1946 to June 2012), EMBASE (June 1980 to June 2012), Cumulative Index to Nursing and Allied Health Literature (CINAHL) (June 1937 to June 2012), PsycINFO (1806 to June 2012), PsycEXTRA (1908 to June 2012), Web of Science (1970 to June 2012), ZETOC (1993 to June 2012), OpenGrey (System for Information on Grey Literature in Europe) (www.opengrey.eu/), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. The electronic databases were last searched on 26 June 2012. We did not search the National Research Register (NNR) as this resource has now been now archived. We contacted pharmaceutical manufacturers to request unpublished data and searched conference proceedings for the Association for Research in Vision and Ophthalmology (ARVO), and the Annual Congress for the Royal College of Ophthalmologists (RCO).

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-RCTs that compared interventions to improve adherence to ocular hypotensive therapy for patients with OHT or glaucoma.

DATA COLLECTION AND ANALYSIS

At least two authors independently assessed the search results for eligibility and extracted data for included trials onto specifically designed forms. We did not pool data due to clinical and methodological heterogeneity.

MAIN RESULTS

Sixteen trials (1565 participants) met the inclusion criteria. Seven studies investigated some form of patient education. In six of these studies this education was combined with other behavioural change interventions including tailoring daily routines to promote adherence to eye drops. Eight studies compared different drug regimens (one of these trials also compared open and masked monitoring) and one study investigated a reminder device. The studies were of variable quality and some were at considerable risk of bias; in general, the length of follow-up was short at less than six months with only two studies following up to 12 months. Different interventions and outcomes were reported and so it was not possible to produce an overall estimate of effect. There was some evidence from three studies that education combined with personalised interventions, that is, more complex interventions, improved adherence to ocular hypotensive therapy. There was less information on other outcomes such as persistence and intraocular pressure, and no information on visual field defects, quality of life and cost. There was weak evidence as to whether people on simpler drug regimens were more likely to adhere and persist with their ocular hypotensive therapy. A particular problem was the interpretation of cross-over studies, which in general were not reported correctly. One study investigated a reminder device and monitoring but the study was small and inconclusive.

AUTHORS' CONCLUSIONS

Although complex interventions consisting of patient education combined with personalised behavioural change interventions, including tailoring daily routines to promote adherence to eye drops, may improve adherence to glaucoma medication, overall there is insufficient evidence to recommend a particular intervention. The interventions varied between studies and none of the included studies reported on the cost of the intervention. Simplified drug regimens also could be of benefit but again the current published studies do not provide conclusive evidence. Future studies should follow up for at least one year, and could benefit from standardised outcomes.

Improved adherence to tacrolimus once-daily formulation in renal recipients: a randomized controlled trial using electronic monitoring

BACKGROUND

With effective agents available to prevent posttransplantation acute organ rejection, medication adherence becomes a key factor for successful treatment outcomes after renal transplantation. A once-daily, modified-release oral formulation of tacrolimus has been developed to simplify dosing and improve medication adherence.

METHODS

Adherence Measurement in Stable Renal Transplant Patients Following Conversion From Prograft to Advagraf is a randomized multicenter controlled trial to evaluate adherence between a tacrolimus once-daily regimen and a tacrolimus twice-daily regimen using an electronic monitor to document drug intake. After enrolment, all patients continued the twice-daily regimen for 3 months and then were randomized 2:1 between the two formulations and followed for 6 months. Adherence was decomposed into patients' persistence and implementation of each regimen.

RESULTS

Two hundred nineteen patients (45% male; 3±2 years after transplantation) were analyzed (145 once daily and 74 twice daily). At 6 months after randomization, 81.5% of the once-daily group and 71.9% of the twice-daily group remained persistent with the treatment (P=0.0824). Among patients who remained engaged with the regimen, 88.2% of the once-daily group and 78.8% of the twice-daily group (P=0.0009) took the prescribed number of daily doses. When the patients took the twice-daily regimen, the average percentage of missed doses was 11.7% in the morning and 14.2% in the evening (P=0.0035).

CONCLUSIONS

Regimen implementation of tacrolimus once daily is significantly superior to the twice-daily regimen. There was a residual prevalence of suboptimal adherence that will have to be countered by means other than reformulation and regimen simplification. Electronically compiled dosing histories provide detailed data on patient adherence that can be used for efficient medication management.

Balanced prescribing - principles and challenges

Balanced prescribing is a process that recommends a medicine appropriate to the patient's condition and, within the limits created by the uncertainty that attends therapeutic decisions, a dosage regimen that optimizes the balance of benefit to harm. The essential steps in achieving this are (a) careful attention to the history, examination, and investigation of the patient's condition and drug therapy, (b) accurate diagnosis, (c) detailed attention to prescribing the dosage regimen in the light of the therapeutic goal, (d) careful writing of the prescription and (e) regular monitoring of therapy, including attention to beneficial outcomes, adverse reactions, and patient adherence. The two major requirements in determining the dosage regimen are (1) understanding the pathophysiology of a health problem and matching it to the mechanisms of action of the relevant medicines and (2) assessing the benefit to harm balance of the therapy, although the difficulties in doing this in the individual are great. Major challenges in prescribing include provision of adequate education for all prescribers early in their undergraduate training and maintaining their expertise after graduation, obtaining evidence to inform appropriate monitoring of therapy, reducing the incidence of medication errors, and providing high quality information that will at the same time guide prescribing decisions and be sufficiently flexible to allow prescribers to tailor therapy to the needs of the individual patient. Careful attention to all facets of prescribing can improve the chances of benefit, reduce the risks of adverse reactions and interactions, and enhance adherence to therapy.

Definitions, variants, and causes of nonadherence with medication: a challenge for tailored interventions

BACKGROUND

Nonadherence with medication is a complex and multidimensional health care problem. The causes may be related to the patient, treatment, and/or health care provider. As a consequence, substantial numbers of patients do not benefit optimally from pharmacotherapy, resulting in increased morbidity and mortality as well as increased societal costs. Several interventions may contribute to improved adherence. However, most interventions have only a modest effect. Thus, despite the many efforts made, there has been little progress made as yet in tackling the problem of nonadherence.

METHODS

This paper summarizes the definitions and taxonomy of adherence with medication, as well as types and causes of nonadherence. In addition, interventions aimed at improvement of adherence are discussed.

CONCLUSION

There is not just one solution for the nonadherence problem that fits all patients. Most interventions to improve adherence are aimed at all patients regardless of whether they are adherent or not. Recently, a number of tailored interventions have been described in the literature. Modern techniques are useful. Electronic pill boxes combined with Short Message Service reminders are specifically designed to improve unintentional adherence and have resulted in an increase in refill adherence in diabetic patients with suboptimal adherence. Tailored Internet interventions are a possibility for influencing patient drug-taking behavior and show promising results. Tailored counseling interventions targeted at the underlying causes of nonadherence seem an attractive method for supporting patients with their use of drugs. However, despite the plausible theoretical framework, data on long-term health effects of the various interventions are not available. To improve adherence effectively, there is a need for a tailored approach based on the type and cause of nonadherence and the specific needs of the patient.

Inclusion of compliance and persistence in economic models: past, present and future

Economic models are developed to provide decision makers with information related to the real-world effectiveness of therapeutics, screening and diagnostic regimens. Although compliance with these regimens often has a significant impact on real-world clinical outcomes and costs, compliance and persistence have historically been addressed in a relatively superficial fashion in economic models. In this review, we present a discussion of the current state of economic modelling as it relates to the consideration of compliance and persistence. We discuss the challenges associated with the inclusion of compliance and persistence in economic models and provide an in-depth review of recent modelling literature that considers compliance or persistence, including a brief summary of previous reviews on this topic and a survey of published models from 2005 to 2012. We review the recent literature in detail, providing a therapeutic-area-specific discussion of the approaches and conclusions drawn from the inclusion of compliance or persistence in economic models. In virtually all publications, variation of model parameters related to compliance and persistence was shown to have a significant impact on predictions of economic outcomes. Growing recognition of the importance of compliance and persistence in the context of economic evaluations has led to an increasing number of economic models that consider these factors, as well as the use of more sophisticated modelling techniques such as individual simulations that provide an avenue for more rigorous consideration of compliance and persistence than is possible with more traditional methods. However, we note areas of continuing concern cited by previous reviews, including inconsistent definitions, documentation and tenuous assumptions required to estimate the effect of compliance and persistence. Finally, we discuss potential means to surmount these challenges via more focused efforts to collect compliance and persistence data.

Adherence to escitalopram treatment in depression: a study of electronically compiled dosing histories in the 'Depression: the search for phenotypes' study

Poor adherence to depression treatment is common. Understanding determinants of poor adherence to therapy is crucial to ensure optimal clinical outcomes. The aim of this study was to describe characteristics of dosing history in participants with depression receiving once daily escitalopram. Participants were randomly assigned to interpersonal psychotherapy (IPT) or pharmacotherapy. Participants assigned to IPT who did not evidence a response or remission had escitalopram added to their treatment. Adherence to pharmacotherapy was assessed using an electronically monitored pill cap (MEMS). Fifty-four participants on escitalopram alone and 32 on escitalopram+IPT were monitored. After 200 days, 71.7% of the participants in the escitalopram group and 54.8% of those in the escitalopram+IPT group were still engaged with the dosing regimen. Of those engaged in the dosing regimen, 17.9% (average over 210 days) of the participants did not take their medication (nonexecution). In 69% of the days participants took the correct dosage required. On average, participants had three drug holidays and the mean length of a holiday was 7 days per patient. No difference in adherence patterns was observed between patients receiving escitalopram alone vs. IPT+escitalopram. Early discontinuation of treatment and suboptimal daily execution of the prescribed regimen are the most common facets of poor adherence in this study population.

Investigating factors associated with adherence behaviour in patients with chronic myeloid leukemia: an observational patient-centered outcome study

Background:

Optimal adherence to imatinib therapy is of paramount importance to maximise treatment effectiveness in patients with chronic myeloid leukaemia (CML). The main objective of this study was to investigate patient-reported personal factors associated with adherence behaviour.

Methods:

Analysis was conducted on 413 CML patients receiving long-term therapy with imatinib. Adherence behaviour was measured with the Morisky Medication Adherence Scale and personal factors investigated included: quality of life, perceived social support, fatigue, symptom burden, psychological wellbeing and desire for additional information. Key socio-demographic and treatment-related factors were also taken into account. Univariate and multivariate logistic regression analyses were used to investigate factors associated with optimal adherence to therapy.

Results:

In all, 53% of patients reported an optimal adherence behaviour. The final multivariate model retained the following variables as independent predictors of optimal adherence to therapy: desire for more information (ref. no), odds ratio (OR)=0.43 (95% confidence interval (CI), 0.29–0.66; P<0.001), social support (higher score representing greater support), OR=1.29 (95% CI, 1.11–1.49; P<0.001) and concomitant drug burden (ref. no), OR=1.82 (95% CI, 1.18–2.80; P=0.006).

Conclusion:

This study suggests that a higher level of social support, satisfaction with information received and concomitant drug burden are the main factors associated with greater adherence to long-term imatinib therapy.

Nonadherence to treatment protocol in published randomised controlled trials: a review

This review aimed to ascertain the extent to which nonadherence to treatment protocol is reported and addressed in a cohort of published analyses of randomised controlled trials (RCTs). One hundred publications of RCTs, randomly selected from those published in BMJ, New England Journal of Medicine, the Journal of the American Medical Association and The Lancet during 2008, were reviewed to determine the extent and nature of reported nonadherence to treatment protocol, and whether statistical methods were used to examine the effect of such nonadherence on both benefit and harms analyses. We also assessed the quality of trial reporting of treatment protocol nonadherence and the quality of reporting of the statistical analysis methods used to investigate such nonadherence. Nonadherence to treatment protocol was reported in 98 of the 100 trials, but reporting on such nonadherence was often vague or incomplete. Forty-two publications did not state how many participants started their randomised treatment. Reporting of treatment initiation and completeness was judged to be inadequate in 64% of trials with short-term interventions and 89% of trials with long-term interventions. More than half (51) of the 98 trials with treatment protocol nonadherence implemented some statistical method to address this issue, most commonly based on per protocol analysis (46) but often labelled as intention to treat (ITT) or modified ITT (23 analyses in 22 trials). The composition of analysis sets for their benefit outcomes were not explained in 57% of trials, and 62% of trials that presented harms analyses did not define harms analysis populations. The majority of defined harms analysis populations (18 out of 26 trials, 69%) were based on actual treatment received, while the majority of trials with undefined harms analysis populations (31 out of 43 trials, 72%) appeared to analyse harms using the ITT approach. Adherence to randomised intervention is poorly considered in the reporting and analysis of published RCTs. The majority of trials are subject to various forms of nonadherence to treatment protocol, and though trialists deal with this nonadherence using a variety of statistical methods and analysis populations, they rarely consider the potential for bias introduced. There is a need for increased awareness of more appropriate causal methods to adjust for departures from treatment protocol, as well as guidance on the appropriate analysis population to use for harms outcomes in the presence of such nonadherence.