Impact of reducing dosing frequency on adherence to oral therapies: a literature review and meta-analysis (original) (raw)
Related papers
Value in Health, 2012
OBJECTIVES: Non-adherence to prescription medication is a serious problem. Accurate assessment of adherence is important for improving patients' health outcomes and informing decisions made by providers and payers. This study examined how adherence was defined, measured, and reported in the scientific literature. METHODS: A systematic review of studies reporting on adherence to prescription medication for chronic diseases was conducted. Embase ® and MED-LINE ® databases were searched. In addition, bibliographies of identified review papers were assessed for inclusion. Mean overall adherence was estimated using a random effects model. RESULTS: The review included 266 studies that met predefined inclusion criteria. The definition of non-adherence varied across studies; 73.6% of all studies defined non-adherence as missed/skipped doses only, while 24.3% defined it as discontinuation of therapy only, and 2.1% defined it as either. Adherence was recorded using different tools including claims data (55.2%), patient self-reports (30.5%), pill counts (12.8%), and laboratory tests (1.5%). Furthermore, included studies used various metrics to assess determinants of adherence, and some studies used more than one measure. The most common metrics were odds ratios (65.6%), regression coefficients (13.0%), hazard ratios (11.2%), and relative risks (5.4%). The meta-analysis showed that the mean overall adherence was highest in studies that defined non-adherence as missed/skipped doses only (51.7% of all participants). Mean adherence in studies defining non-adherence as discontinuation of therapy only and in studies defining it as missed/skipped doses or discontinuation of therapy was 45.4% and 45.0%, respectively. CONCLUSIONS: Inconsistencies in the adherence literature pose a challenge to the interpretation, usefulness, and synthesis of adherence data. There is a clear need for methodological standardisation in adherence research and assessment.
Dosing frequency and medication adherence in chronic disease
2012
BACKGROUND: Prior research has shown a decrease in medication adherence as dosing frequency increases; however, meta-analyses have not been able to demonstrate a significant inverse relationship between dosing frequency and adherence when comparing twice-daily versus once-daily dosing. OBJECTIVE: To determine the effect of scheduled dosing frequency on medication adherence in patients with chronic diseases. METHODS: A systematic literature search of MEDlINE and Embase from January 1986 to December 2011 and a hand search of references were performed to identify eligible studies. Randomized and observational studies were included if they utilized a prospective design, assessed adult patients with chronic diseases, evaluated scheduled oral medications taken 1 to 4 times daily, and measured medication adherence for at least 1 month using an electronic monitoring device. Manual searches of reference sections of identified studies and systematic reviews were also performed to find other potentially relevant articles. Standard definitions for medication taking, regimen, and timing adherence were used and evaluated. Studies were pooled using a multivariate linear mixed-model method to conduct meta-regression accounting for both random and fixed effects, weighted by the inverse of the variance of medication adherence. RESUlTS: Fifty-one studies, comprising 65, 76, and 47 dosing frequency arms for the taking, regimen, and timing adherence endpoints were included. Unadjusted adherence estimates were highest when the least stringent definition, taking adherence, was used (range for dosing frequencies: 80.1%-93.0%) and lowest when the most stringent definition, timing adherence, was used (range for dosing frequencies: 18.8%-76.9%). In multivariate meta-regression analyses, the adjusted weighted mean percentage adherence rates for all regimens dosed more frequently than once per day were significantly lower compared with once-daily regimens (for 2-times, 3-times, and 4-times daily regimens,
Annals of Internal Medicine, 2012
This review concluded that case management, patient education with behavioural support, and reducing out-of-pocket expenses each improved medication adherence for more than one condition. Whether they could be applied to or improve long-term adherence and health outcomes was uncertain. This was a well-conducted review, and the conclusions are likely to be reliable. Authors' objectives To assess the comparative effectiveness of patient, provider, systems, and policy interventions that aim to improve medication adherence for chronic health conditions in the USA. Searching MEDLINE and The Cochrane Library were searched for studies published in English and included from 1994 to June 2012. Reference lists of relevant reviews were searched. Study selection Randomised controlled trials (RCTs) and observational studies conducted in outpatient primary and specialty care, and community-based and home-based settings were eligible for inclusion if they assessed the effectiveness of interventions to improve adherence to self-administered medication for the secondary or tertiary prevention of chronic diseases in adults. Studies conducted in institutional settings or in patients with acute conditions were excluded, as were studies that evaluated interventions to improve adherence to antiretroviral therapy or medications for mental illness or substance abuse. Studies had to be conducted in the USA. Nearly 40% of the interventions evaluated were for patients only, and just over half were for more than one target (patient, provider, systems, or policy). About half of the interventions were delivered by a pharmacist, physician, or nurse and about half involved at least some face-to-face contact. The medical condition varied considerably across studies, but most patients had cardiovascular disease, diabetes, hypertension, depression or hyperlipidaemia. Two reviewers independently selected studies for the review; disagreements were resolved by consensus or consultation with a third reviewer. Assessment of study quality Two reviewers independently assessed the risk of bias, in the included studies, for the randomisation method, adequacy of allocation concealment, strategies to recruit patients, similarity at baseline, blinding, contamination, attrition, prespecification of outcome measures, confounders (where appropriate), justification of medication adherence thresholds, and the validity, consistency and reliability of outcome measures. Studies considered to be at a high risk of bias (serious errors in their design or analysis) were excluded. The strength of the evidence was graded based on the risk of bias, and the consistency, directness, and precision of the results. Disagreements were resolved by consensus or consultation with a third reviewer. Data extraction One reviewer extracted the proportion of patients with improved adherence and/or summary estimates, such as risk ratios, hazard ratios or odds ratios, with a measure of variance, for relevant outcomes; data were checked by a second reviewer. Methods of synthesis Studies were combined in a narrative synthesis, organised by clinical condition and intervention type. Study details were available in the full report (see Other Publications of Related Interest). Differences between studies were discussed in
THE IMPACT OF MEDICATION REGIMEN COMPLEXITY ON ADHERENCE TO LONG-TERM THERAPIES
Asian Journal of Pharmaceutical and Clinical Research, 2021
Objective: Adherence is a multifactorial phenomenon. Medication-related factors have long been the focus of attention. However, the results are inconsistent. Methods: In a cross-sectional questionnaire-based study of outpatients, we assessed 180 patients suffering from chronic conditions. The objective of this study is to determine the impact of medication regimen complexity on adherence to long-term drug therapies. Results: 91.66% of patients receiving more than four drugs had good or high adherence. 80.94% of patients on thrice a day (or more) drug administration had good or high adherence. 91.66% of patients receiving drug therapy for more than 5 years had good or high adherence. In all other groups, the adherence was low. The adherence was significantly (p<0.05) and positively (rs=0.792 and 0.846) correlated to the frequency of drug administration and duration of treatment. Adherence was positively correlated to the number of drugs per day (rs=0.668) but the relationships were not statistically significant (p=0.102). All the correlations were large. Conclusions: We found adherence positively correlated with medication regimen complexity. An improved understanding of the determinants of medication adherence is needed.
The impact of medication regimen factors on adherence to chronic treatment: a review of literature
Journal of Behavioral Medicine, 2008
This article reviews recent literature in chronic illness or long-term health management including asthma, contraception, diabetes, HIV disease, and hypertension/ cardiovascular disease, mental disorders, pain, and other diseases to determine the relationship between regimen factors and adherence to medications. The authors conducted an electronic literature search to detect articles published between 1998 and 2007. Articles were included if they pertained to a chronic illness or to contraception, included a clear definition of how adherence was measured, and included regimen factors as primary or secondary explanatory variables. Methodology of the studies varied greatly, as did methods of measuring adherence and regimen factors. Surprisingly few of these articles concerned (1) chronic treatment, (2) regimen factors such as dosing, pill burden, and regimen complexity, and (3) adherence measured in a clear manner. Most studies failed to use state-of-the-art methods of measuring adherence. Despite these flaws, a suggestive pattern of the importance of regimen factors, specifically dose frequency and regimen complexity, emerged from this review.
AIDS research and treatment, 2014
Administering drugs as fixed-dose combinations (FDCs) versus the same active drugs administered as separate pills is assumed to enhance treatment adherence. We synthesized evidence from randomized controlled trials (RCTs) about the effect of FDCs versus separate pills on adherence. We searched PubMed for RCTs comparing a FDC with the same active drugs administered as separate pills, including a quantitative estimate of treatment adherence, without restriction to medical condition. The odds ratio (OR) of optimal adherence with FDCs versus separate pills was used as common effect size and aggregated into a pooled effect estimate using a random effect model with inverse variance weights. Out of 1258 articles screened, only six studies fulfilled inclusion criteria. Across medical conditions, administering drugs as FDC significantly increased the likelihood of optimal adherence (OR 1.33 (95% CI, 1.03-1.71)). Within subgroups of specific medical conditions, the favourable effect of FDCs o...
Treatment adherence in chronic disease
Journal of Clinical Epidemiology, 2001
Research has addressed the problem of poor adherence for the past 4 decades. Much of the research has focused on the prevalence and predictors of adherence, research methodologies, and the development of measures of adherence. To a much lesser extent, attention has been given to intervention studies designed to evaluate strategies to improve adherence to treatment regimens. This article provides an up-to-date review of the literature on medication adherence in chronic disease.
Patient Preference and Adherence
Background: This study aims to identify interventions used to reduce medication regimen complexity and to assess their impact on medication adherence and clinical outcomes. Methods: A literature search was conducted using pre-defined search terms in three scientific databases, including ScienceDirect, ProQuest and MEDLINE. Original research articles published in English between 2009 and 2020 that assessed the impact of medication regimen simplification on medication adherence in patients with long-term medical conditions were eligible for inclusion. Review articles, meta-analysis studies and conference proceedings were excluded. Data charting was done in an iterative process using a studyspecific extraction form. Results: Of the 684 studies identified through initial searches, 17 studies were included in the review. Nine studies involved simplification of medication regimen related to HIV, while three studies focused on patients with diabetes with or without coronary artery disease. The remaining five studies included medications used among elderly patients or medications related to hypertension, psychiatric disorders, glaucoma and kidney diseases. Three medication regimen simplification strategies were identified; fixed-dose combination (n = 7), oncedaily dosing (n = 4) and the combination of both fixed-dose and once-daily dosing (n = 6). Overall, most of the regimen simplification strategies (14 out of 17) were found to be useful in improving medication adherence. There was no assessment of clinical outcomes in four out of 17 studies. Furthermore, more than half of the studies that assessed clinical outcomes did not show any additional impact on clinical outcomes. Conclusion: The findings suggest that there was an equal utilization of the three main approaches of regimen simplifications; fixed-dose combination, once-daily dosing and a combination of both. Overall, most of the regimen simplification strategies were found to be effective in improving medication adherence. However, the associated improvement in medication adherence did not extend to improvement in the clinical outcomes.
2012
OBJECTIVES To assess the effectiveness of patient, provider, and systems interventions (Key Question [KQ] 1) or policy interventions (KQ 2) in improving medication adherence for an array of chronic health conditions. For interventions that are effective in improving adherence, we then assessed their effectiveness in improving health, health care utilization, and adverse events. DATA SOURCES MEDLINE®, the Cochrane Library. Additional studies were identified from reference lists and technical experts. REVIEW METHODS Two people independently selected, extracted data from, and rated the risk of bias of relevant trials and systematic reviews. We synthesized the evidence for effectiveness separately for each clinical condition, and within each condition, by type of intervention. We also evaluated the prevalence of intervention components across clinical conditions and the effectiveness of interventions for a range of vulnerable populations. Two reviewers graded the strength of evidence us...