A critical evaluation of the methodology of the literature on medication compliance

Interventions to improve medication adherence in inflammatory bowel disease: A systematic review

OBJECTIVE

To summarize existing literature examining interventions to enhance medication adherence and their effectiveness in enhancing care for inflammatory bowel disease (IBD) patients.

METHODS

This review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. PubMed and Embase were searched for studies from June 2014 to Dec 2020. Only the studies published in English were included.

RESULTS

Our systematic literature search identified 488 published articles. Seventeen studies with a total of 7073 patients were included. Out of seventeen different interventions, five were classified as educational, eight as multicomponent, three as behavioral and one as cognitive behavioral. Adherence was measured using patient self-report, administrative/pharmacy claims data, and electronic monitoring devices/pill dispensing systems. Twelve out of seventeen interventions showed a statistically significant improvement in medication adherence including three educational, seven multicomponent, one behavioral and one cognitive behavioral intervention.

CONCLUSIONS

Multicomponent interventions demonstrated the greatest success in IBD patients in promoting medication adherence. Future research should focus on a multidisciplinary approach to design multicomponent interventions to optimize treatment adherence and enhance long-term clinical outcomes.

PRACTICE IMPLICATIONS

While stand-alone strategies have demonstrated effectiveness in improving adherence, better outcomes may be achieved by combining multiple strategies.

Use of digital technology tools to characterize adherence to prescription-grade omega-3 polyunsaturated fatty acid therapy in post-myocardial or hypertriglyceridemic patients: Primary results of the DIAPAsOn prospective observational study (Preprint)

Background

Maintaining sustained adherence to medication for optimal management of chronic noninfectious diseases, such as atherosclerotic vascular disease, is a well-documented therapeutic challenge.

Objective

The DIAPAsOn study was a 6-month, multicenter prospective observational study in the Russian Federation that examined adherence to a preparation of highly purified omega-3 polyunsaturated fatty acids (Omacor) in 2167 adult patients with a history of recent myocardial infarction or endogenous hypertriglyceridemia.

Methods

A feature of DIAPAsOn was the use of a bespoke electronic patient engagement and data collection system to monitor adherence. Adherence was also monitored by enquiry at clinic visits. A full description of the study’s aims and methods has appeared in JMIR Research Protocols.

Results

The net average reduction from baseline in both total and low-density lipoprotein cholesterol was approximately 1 mmol/L and the net average increase in high-density lipoprotein cholesterol was 0.2 (SD 0.53) mmol/L (P<.001 for all outcomes vs baseline). The mean triglyceride level was 3.0 (SD 1.3) mmol/L at visit 1, 2.0 (SD 0.9) mmol/L at visit 2, and 1.7 (SD 0.7) mmol/L at visit 3 (P<.001 for later visits vs visit 1). The percentage of patients with a triglyceride level <1.7 mmol/L rose from 13.1% (282/2151) at baseline to 54% (1028/1905) at the end of the study. Digital reporting of adherence was registered by 8.3% (180/2167) of patients; average scores indicted poor adherence. However, a clinic-based enquiry suggested high levels of adherence. Data on health-related quality of life accrued from digitally engaged patients identified improvements among patients reporting high adherence to study treatment, but patient numbers were small.

Conclusions

The lipid and lipoprotein findings indicate that Omacor had nominally favorable effects on the blood lipid profile. Less than 10% of patients enrolled in DIAPAsOn used the bespoke digital platform piloted in the study, and the level of self-reported adherence to medication by these patients was also low. Reasons for this low uptake and adherence are unclear. Better adherence was recorded in clinical reports.

Trial Registration

ClinicalTrials.gov NCT03415152; https://clinicaltrials.gov/ct2/show/NCT03415152

Digital Technology Tools to Examine Patient Adherence to a Prescription-Only Omega-3 Polyunsaturated Fatty Acid Therapy To Mitigate Cardiovascular Risk: Protocol for a Prospective Observational Study and Preliminary Demographic Analysis

Background

Sustained adherence and persistence with prescription medications is considered essential to achieve maximal treatment benefit for patients with major chronic, noncommunicable diseases such as hyperlipidemia and lipid-associated cardiovascular disease. It is widely documented, however, that many patients with these conditions have poor long-term adherence to their treatments. The population of Russia is affected by poor adherence in the same ways as populations elsewhere and continues to have high rates of cardiovascular disease.

Objective

The purpose of this study was to examine patient adherence to a prescription-only preparation of highly purified omega-3 polyunsaturated fatty acids (1.2 to 1 eicosapentaenoic acid to docosahexaenoic ratio, 90% purity) in a large sample of patients at risk for cardiovascular diseases using digital technology to monitor patient behavior and as an outreach facility for patient education and engagement.

Methods

We conducted a 6-month prospective observational study (DIAPAsOn) at >100 centers in the Russian Federation. A bespoke electronic data capture and patient engagement system were developed with a well-established Russian technology supplier that enables information obtained during clinic visits to be supplemented by remote patient self-reporting. Other aspects of the program included raising patients' awareness about their condition via educational materials available in personal patient accounts in the electronic system.

Results

From an initial cohort of 3000 patients, a safety population of 2572 patients (age: mean 60 years) with an equal proportion of men and women has been characterized. There was widespread concomitant cardiovascular pathology and commensurate use of multiple classes of cardiovascular medication, notably lipid-modifying and antihypertensive drugs. The program was completed by 1975 patients, of whom 780 were prescribed highly purified omega-3 polyunsaturated fatty acid supplements for secondary prevention after myocardial infarction and 1195 were prescribed highly purified omega-3 polyunsaturated fatty acid supplements for hypertriglyceridemia. Data collection and analysis have been completed.

Conclusions

DIAPAsOn will provide insights into patient adherence with prescription-grade omega-3 polyunsaturated fatty acid therapy and perspectives on the role of mobile technology in monitoring and encouraging adherence to therapy.

Strategies for improving adherence to antiepileptic drug treatment in people with epilepsy

BACKGROUND

Poor adherence to antiepileptic medication is associated with increased mortality, morbidity and healthcare costs. In this review, we focus on interventions designed and tested in randomised controlled trials (RCTs) and quasi-RCTs to assist people with adherence to antiepileptic medication. This is an update of a Cochrane review first published in 2011, and last updated in 2017.

OBJECTIVES

To determine the effectiveness of interventions aimed at improving adherence to antiepileptic medication in adults and children with epilepsy.

SEARCH METHODS

For the latest update, we searched the following databases on 18 February 2020: Cochrane Register of Studies (CRS Web), MEDLINE, CINAHL Plus and PsycINFO. CRS Web includes RCTs or quasi-RCTs from PubMed, Embase, ClinicalTrials.gov, the World Health Organization International Clinical Trials Registry Platform (ICTRP), CENTRAL, and the Specialized Registers of Cochrane Review Groups including Epilepsy. We also searched the reference lists of relevant articles.

SELECTION CRITERIA

RCTs and quasi-RCTs of adherence-enhancing interventions aimed at people with a clinical diagnosis of epilepsy (as defined in individual studies), of any age and treated with antiepileptic drugs in a primary care, outpatient or other community setting.

DATA COLLECTION AND ANALYSIS

All review authors independently assessed lists of potentially relevant citations and abstracts. At least two review authors independently extracted data and performed a quality assessment of each study according to the Cochrane tool for assessing risk of bias. We graded the level of evidence for each outcome according to GRADE. The studies differed widely according to the type of intervention and measures of adherence; therefore combining data was not appropriate.

MAIN RESULTS

We included 20 studies reporting data on 2832 participants. Thirteen studies targeted adults with epilepsy, one study included participants of all ages, one study included participants older than two years, one recruited pediatric patients aged between 1 month to 15 years, one study targeted caregivers of children with epilepsy, one targeted adolescents and caregivers, and two studies targeted families of children with epilepsy. We identified three ongoing studies. Follow-up time was generally short in most studies, ranging from 1 to 12 months. The studies examined three main types of interventions: educational interventions, behavioural interventions and mixed interventions. All but three studies compared treatment with usual care or 'no intervention'. Due to heterogeneity between studies in terms of interventions, methods used to measure adherence and the way the studies were reported, we did not pool the results and these findings were inappropriate to be included in a meta-analysis. Education and counselling of participants with epilepsy had mixed success (moderate-certainty evidence). Behavioural interventions such as the use of intensive reminders provided more favourable effects on adherence (moderate-certainty evidence). The effect on adherence to antiepileptic drugs described by studies of mixed interventions showed improved adherence in the intervention groups compared to the control groups (high-certainty evidence). Eleven studies described seizure frequency or seizure severity or both, with four of them, reporting improved adherence and decreased seizure frequency in the intervention groups (moderate-certainty evidence). Findings related to self-efficacy and quality of life were mixed, with no clear pattern across types of intervention.

AUTHORS' CONCLUSIONS

Behavioural interventions such as intensive reminders and the use of mixed interventions demonstrate some positive results, however, we need more reliable evidence on their efficacy, derived from carefully-designed RCTs before we can draw a firm conclusion. None of the newly included studies have provided additional information that would lead to significant changes in our conclusions.

Real-world adherence to oral anticoagulants in atrial fibrillation patients: a study protocol for a systematic review and meta-analysis

INTRODUCTION

Atrial fibrillation (AF) is one of the leading causes of cerebrovascular mortality and morbidity. Oral anticoagulants (OACs) have been shown to reduce the incidence of cardioembolic stroke in patients with AF, adherence to treatment being an essential element for their effectiveness. Since the release of the first non-vitamin K antagonist oral anticoagulant, several observational studies have been carried out to estimate OAC adherence in the real world using pharmacy claim databases or AF registers. This systematic review aims to describe secondary adherence to OACs, to compare adherence between OACs and to analyse potential biases in OAC secondary adherence studies using databases.

METHODS AND ANALYSIS

We searched on PubMed, SCOPUS and Web of Science databases (completed in 26 September 2018) to identify longitudinal observational studies reporting days' supply adherence measures with OAC in patients with AF from refill databases or AF registers. The main study endpoint will be the percentage of patients exceeding the 80% threshold in proportion of days covered or the medication possession ratio. Two reviewers will independently screen potential studies and will extract data in a structured format. A random-effects meta-analysis will be carried out to pool study estimates. The risk of bias will be assessed using the Newcastle-Ottawa Scale for observational studies and we will also assess some study characteristics that could affect days' supply adherence estimates.

ETHICS AND DISSEMINATION

This systematic review using published aggregated data does not require ethics approval according to Spanish law and international regulations. The final results will be published in a peer-review journal and different social stakeholders, non-academic audiences and patients will be incorporated into the diffusion activities.

PROSPERO REGISTRATION NUMBER

CRD42018095646.

Explaining the decline in coronary heart disease mortality rates in the Slovak Republic between 1993-2008

Objective

Between the years 1993 and 2008, mortality rates from coronary heart disease (CHD) in the Slovak Republic have decreased by almost one quarter. However, this was a smaller decline than in neighbouring countries. The aim of this modelling study was therefore to quantify the contributions of risk factor changes and the use of evidence-based medical therapies to the CHD mortality decline between 1993 and 2008.

Methods

We identified, obtained and scrutinised the data required for the model. These data detailed trends in the major population cardiovascular risk factors (smoking, blood pressure, total cholesterol, diabetes prevalence, body mass index (BMI) and physical activity levels), and also the uptake of all standard CHD treatments. The main data sources were official statistics (National Health Information Centre and Statistical Office of the Slovak Republic) and national representative studies (AUDIT, SLOVAKS, SLOVASeZ, CINDI, EHES, EHIS). The previously validated IMPACT policy model was then used to combine and integrate these data with effect sizes from published meta-analyses quantifying the effectiveness of specific evidence-based treatments, and population-wide changes in cardiovascular risk factors. Results were expressed as deaths prevented or postponed (DPPs) attributable to risk factor changes or treatments. Uncertainties were explored using sensitivity analyses.

Results

Between 1993 and 2008 age-adjusted CHD mortality rates in the Slovak Republic (SR) decreased by 23% in men and 26% in women aged 25–74 years. This represented some 1820 fewer CHD deaths in 2008 than expected if mortality rates had not fallen. The IMPACT model explained 91% of this mortality decline. Approximately 50% of the decline was attributable to changes in acute phase and secondary prevention treatments, particularly acute and chronic treatments for heart failure (≈12%), acute coronary syndrome treatments (≈9%) and secondary prevention following AMI and revascularisation (≈8%). Changes in CHD risk factors explained approximately 41% of the total mortality decrease, mainly reflecting reductions in total serum cholesterol. However, other risk factors demonstrated adverse trends and thus generated approximately 740 additional deaths.

Conclusion

Our analysis suggests that approximately half the CHD mortality fall recently observed in the SR may be attributable to the increased use of evidence-based treatments. However, the adverse trends observed in all the major cardiovascular risk factors (apart from total cholesterol) are deeply worrying. They highlight the need for more energetic population-wide prevention policies such as tobacco control, reducing salt and industrial trans fats content in processed food, clearer food labelling and regulated marketing of processed foods and sugary drinks.

Strategies for improving adherence to antiepileptic drug treatment in people with epilepsy

BACKGROUND

Poor adherence to antiepileptic medication is associated with increased mortality, morbidity and healthcare costs. In this review, we focus on interventions designed and tested in randomised controlled trials and quasi-randomised controlled trials to assist people with adherence to antiepileptic medication. This is an updated version of the original Cochrane review published in the Cochrane Library, Issue 1, 2010.

OBJECTIVES

To determine the effectiveness of interventions aimed at improving adherence to antiepileptic medication in adults and children with epilepsy.

SEARCH METHODS

For the latest update, on 4 February 2016 we searched the Cochrane Epilepsy Group Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL) via the Cochrane Register of Studies Online (CRSO), MEDLINE (Ovid 1946 to 4 February 2016), CINAHL Plus (EBSCOhost 1937 to 4 February 2016), PsycINFO (EBSCOhost 1887 to 4 February 2016), ClinicalTrials.gov, and the WHO International Clinical Trials Registry Platform. We also searched the reference lists of relevant articles.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials of adherence-enhancing interventions aimed at people with a clinical diagnosis of epilepsy (as defined in individual studies), of any age and treated with antiepileptic drugs in a primary care, outpatient or other community setting.

DATA COLLECTION AND ANALYSIS

All review authors independently assessed lists of potentially relevant citations and abstracts. At least two review authors independently extracted data and performed quality assessment of each study according to the Cochrane tool for assessing risk of bias. We graded the level of evidence for each outcome according to the GRADE working group scale.The studies differed widely according to the type of intervention and measures of adherence; therefore combining data was not appropriate.

MAIN RESULTS

We included 12 studies reporting data on 1642 participants (intervention = 833, control = 809). Eight studies targeted adults with epilepsy, one study included participants of all ages, one study included participants older than two years, one study targeted caregivers of children with epilepsy, and one study targeted families of children with epilepsy. We identified six ongoing trials. Follow-up time was generally short in most trials, ranging from one to 12 months. The trials examined three main types of interventions: educational interventions, behavioural interventions and mixed interventions. All studies compared treatment versus usual care or 'no intervention', except for two studies. Due to heterogeneity between studies in terms of interventions, methods used to measure adherence and the way the studies were reported, we did not pool the results and these findings were inappropriate to be included in a meta-analysis. Education and counselling of participants with epilepsy resulted in mixed success (moderate-quality evidence). Behavioural interventions such as use of intensive reminders provided more favourable effects on adherence (moderate-quality evidence). The effect on adherence to antiepileptic drugs described by studies of mixed interventions showed improved adherence in the intervention groups compared to the control groups (high-quality evidence).

AUTHORS' CONCLUSIONS

Behavioural interventions such as intensive reminders and the use of mixed interventions demonstrate some positive results; however, we need more reliable evidence on their efficacy, derived from carefully-designed randomised controlled trials before we can draw a firm conclusion. Since the last version of this review, none of the new relevant studies have provided additional information that would lead to significant changes in our conclusions. This current update includes 12 studies, of which six came from the latest searches.

Patients' beliefs and attitudes about their treatment for inflammatory bowel disease in Korea

BACKGROUND AND AIMS

Adherence to medication during the treatment of inflammatory bowel disease (IBD) is important in terms of maintaining remission. According to studies on adherence to medication in other chronic diseases, non-adherence is associated with negative attitudes to treatment. The aims of this study were to assess adherence rates and IBD patients' beliefs and attitudes regarding medication using a questionnaire based approach.

METHODS

Two hundred and eighty seven patients from three tertiary hospitals were enrolled and completed a questionnaire that addressed adherence (Medication Adherence Report Scale, MARS), beliefs, and attitudes to medication (Beliefs about Medications Questionnaire, BMQ).

RESULTS

Using a cutoff score of 16/20 for MARS, 64 (22.3%) patients did not adhere to medication. According to attitude analysis conducted using the BMQ, 41.8% of the 287 study subjects felt high necessity but low concern for the medication ("accepting") and 34.8% felt high necessity and concern ("ambivalent"). Multivariate analysis showed significantly lower adherence to medication among younger patients, patients with experience of adverse effects to medication, patients with demanding jobs, and for those with an "indifferent" or "skeptical" attitude regarding the benefits of medication. On the other hand, IBD patients with "accepting" attitude adhered to medication.

CONCLUSION

Twenty-two percent of IBD patients were non-adherent to medical treatment, and belief of the need for medication was found to significantly enhance adherence. Interventions, such as education about the efficacy and safety of medications, should be considered to facilitate adherence to medical treatment among IBD patients.

Decline in Coronary Mortality in Sweden between 1986 and 2002: Comparing Contributions from Primary and Secondary Prevention

Background

The relative importance of risk factor reduction in healthy people (primary prevention) versus that in patients with coronary heart disease (secondary prevention) has been debated. We aimed to quantify the contribution of the two.

Methodology

We used the previously validated IMPACT model to estimate contributions from primary prevention (reducing risk factors in the population, particularly smoking, cholesterol and systolic blood pressure) and from secondary prevention (reducing risk factors in coronary heart disease patients) in the Swedish population.

Principal Findings

Between 1986 and 2002, about 8,690 fewer deaths were related to changes in the three major risk factors. Population cholesterol fell by 0.64 mmol/L, with approximately 5,210 fewer deaths attributable to diet changes (4,470 in healthy people740 in patients.) plus 810 to statin treatment (200 in healthy people, 610 in patients). Overall smoking prevalence decreased by 10.3%, resulting in 1,195 fewer deaths, attributable to smoking cessation (595 in healthy people, 600 in patients). Mean population systolic blood pressure fell by 2.6 mmHg, resulting in 900 fewer deaths (865 in healthy people, 35 in patients), plus 575 fewer deaths attributable to antihypertensive medication in healthy people. The majority of falls in deaths attributable to risk factors occurred in people without known heart disease: 6,705 fewer deaths compared with 1,985 fewer deaths in patients (secondary prevention), emphasizing the importance of promoting health interventions in the general population.

Conclusions

The largest effects on mortality came from primary prevention, giving markedly larger mortality reductions than secondary prevention.

Adherence to oral migraine-preventive medications among patients with chronic migraine

BACKGROUND

Chronic migraine (CM) is a disabling disorder characterized by ≥15 headache days per month that has been shown to significantly reduce quality of life. Migraine-prevention guidelines recommend preventive medications as the standard of care for patients with frequent migraine. The aim of this study was to assess adherence to 14 commonly prescribed oral migraine-preventive medications (OMPMs) among patients with CM.

METHODS

Retrospective claims analysis of a US claim database (Truven MarketScan® Databases) was queried to identify patients who were at least 18 years old, diagnosed with CM, and initiated an OMPM (antidepressants, beta blockers, or anticonvulsants) between January 1, 2008 and September 30, 2012. Medication possession ratios (MPR) and proportion of days covered (PDC) were calculated for each patient. A cutoff of ≥80% was used to classify adherence. The odds of adherence between OMPMs were compared using logistic regression models.

RESULTS

Of the 75,870 patients identified with CM, 8688 met the inclusion/exclusion criteria. Adherence ranged between 26% to 29% at six months and 17% to 20% at 12 months depending on the calculation used to classify adherence (PDC and MPR, respectively). Adherence among the 14 OMPMs was similar except for amitriptyline, nortriptyline, gabapentin, and divalproex, which had significantly lower odds of adherence when compared to topiramate.

CONCLUSION

Adherence to OMPMs is low among the US CM population at six months and worsens by 12 months.

Explaining the decline in coronary heart disease mortality in Turkey between 1995 and 2008

Background

Coronary heart disease (CHD) mortality rates have been decreasing in Turkey since the early 1990s. Our study aimed to determine how much of the CHD mortality decrease in Turkey between 1995 and 2008 could be attributed to temporal trends in major risk factors and how much to advances in medical and surgical treatments.

Methods

The validated IMPACT CHD mortality model was used to combine and analyse data on uptake and effectiveness of CHD treatments and risk factor trends in Turkey in adults aged 35–84 years between 1995 and 2008.

Data sources were identified, searched and appraised on population, mortality and major CHD risk factors for adults those aged 35–84 years. Official statistics, electronic databases, national registers, surveys and published trials were screened from 1995 onwards.

Results

Between 1995 and 2008, coronary heart disease mortality rates in Turkey decreased by 34% in men and 28% in women 35 years and over. This resulted in 35,720 fewer deaths in 2008.

Approximately 47% of this mortality decrease was attributed to treatments in individuals (including approximately 16% to secondary prevention, 3% angina treatments, 9% to heart failure treatments, 5% to initial treatments of acute myocardial infarction, and 5% to hypertension treatments) and approximately 42% was attributable to population risk factor reductions (notably blood pressure 29%; smoking 27%; and cholesterol 1%). Adverse trends were seen for obesity and diabetes (potentially increasing mortality by approximately 11% and 14% respectively). The model explained almost 90% of the mortality fall.

Conclusion

Reduction in major cardiovascular risk factors explained approximately 42% and improvements in medical and surgical treatments explained some 47% of the CHD mortality fall. These findings emphasize the complimentary value of primary prevention and evidence-based medical treatments in controlling coronary heart disease.

A systematic literature review of psychosocial and behavioral factors associated with initial medication adherence: a report of the ISPOR medication adherence & persistence special interest group

OBJECTIVES

Numerous factors influencing medication adherence in chronically ill patients are well documented, but the paucity of studies concerning initial treatment course experiences represents a significant knowledge gap. As interventions targeting this crucial first phase can affect long-term adherence and outcomes, an international panel conducted a systematic literature review targeting behavioral or psychosocial risk factors.

METHODS

Eligible published articles presenting primary data from 1966 to 2011 were abstracted by independent reviewers through a validated quality instrument, documenting terminology, methodological approaches, and factors associated with initial adherence problems.

RESULTS

We identified 865 potentially relevant publications; on full review, 24 met eligibility criteria. The mean Nichol quality score was 47.2 (range 19-74), with excellent reviewer concordance (0.966, P < 0.01). The most prevalent pharmacotherapy terminology was initial, primary, or first-fill adherence. Articles described the following factors commonly associated with initial nonadherence: patient characteristics (n = 16), medication class (n = 12), physical comorbidities (n = 12), pharmacy co-payments or medication costs (n = 12), health beliefs and provider communication (n = 5), and other issues. Few studies reported health system factors, such as pharmacy information, prescribing provider licensure, or nonpatient dynamics.

CONCLUSIONS

Several methodological challenges synthesizing the findings were observed. Despite implications for continued medication adherence and clinical outcomes, relatively few articles directly examined issues associated with initial adherence. Notwithstanding this lack of information, many observed factors associated with nonadherence are amenable to potential interventions, establishing a solid foundation for appropriate ongoing behaviors. Besides clarifying definitions and methodology, future research should continue investigating initial prescriptions, treatment barriers, and organizational efforts to promote better long-term adherence.

Feasibility and reliability of interactive voice response assessment of HIV medication adherence: research and clinical implications

BACKGROUND

There are well-documented negative consequences of nonadherence to HIV medications. Telephone-based interactive voice response (IVR) technologies may hold promise for assessing nonadherence in both research and clinical contexts; however, little psychometric research has been conducted on this topic.

OBJECTIVE

In the present pilot study, we test the feasibility and reliability of a simplified patient-initiated, daily IVR system with a convenience sample of HIV patients attending a university-affiliated infectious disease clinic.

METHODS

Participants were asked to call in to an IVR system to report adherence daily during 2 weeks of a larger prospective study. Response rates and patterns were analyzed for feasibility and compared to retrospective, self-report timeline follow-back (TLFB) adherence reporting.

RESULTS

The IVR protocol showed moderate feasibility, with participants reporting adherence behavior on 63.4% of days. However, agreement with TLFB data was low, particularly for days in which participants reported incomplete adherence.

CONCLUSIONS

The IVR protocol tested in the current trial shows some promise. Completion rates were higher than in previous trials. Future research is needed to further enhance the feasibility of IVR for HIV medication adherence and to compare responses to more objective measures on HIV adherence.

Explaining the decline in coronary heart disease mortality in the Czech Republic between 1985 and 2007

BACKGROUND

Coronary heart disease (CHD) mortality has declined substantially in the Czech Republic over the last two decades.

DESIGN

The purpose of this study was to determine what proportion of this CHD mortality decline could be associated with temporal trends in major CHD risk factors and what proportion with advances in medical and surgical treatments.

METHODS

The validated IMPACT mortality model was used to combine and analyse data on uptake and effectiveness of CHD management and risk factor trends in the Czech Republic in adults aged 25-74 years between 1985 and 2007. The main sources were official statistics, national quality of care registries, published trials and meta-analyses, and the Czech MONICA and Czech post-MONICA studies.

RESULTS

Between 1985 and 2007, age-adjusted CHD mortality rates in the Czech Republic decreased by 66.2% in men and 65.4% in women in the age group 25-74 years, representing 12,080 fewer CHD deaths in 2007. Changes in CHD risk factors explained approximately 52% of the total mortality decrease, and improvements in medical treatments approximately 43%. Increases in body mass index and in diabetes prevalence had a negative impact, increasing CHD mortality by approximately 1% and 5%, respectively.

CONCLUSIONS

More than half of the very substantial fall in CHD mortality in the Czech Republic between 1985 and 2007 was attributable to reduction in major cardiovascular risk factors. Improvement in treatments accounted for approximately 43% of the total mortality decrease. These findings emphasize the value of primary prevention and evidence-based medical treatment.

Modelling coronary heart disease mortality in Northern Ireland between 1987 and 2007: broader lessons for prevention

AIMS

To quantify how much of the coronary heart disease (CHD) mortality decline in Northern Ireland between 1987 and 2007 could be attributed to medical and surgical treatments and how much to changes in population cardiovascular risk factors.

METHODS AND RESULTS

The IMPACT mortality model was used to integrate data on uptake and effectiveness of cardiological treatments and risk factor trends in the Northern Ireland population between 1987 and 2007. The main data sources were official population and mortality statistics, hospital administration systems, primary care datasets, published trials and meta-analyses, clinical audits, and national surveys. Between 1987 and 2007, CHD mortality rates in Northern Ireland decreased by 52% in men and 60% in women aged 25-84 years. This resulted in 3180 fewer deaths in 2007 than expected if 1987 mortality rates had persisted. Approximately 35% of this decrease was attributed to increased uptake of treatments in individuals and 60% to population risk factor reductions (principally blood pressure, total cholesterol, and smoking); however, these reductions were partially offset by adverse trends in diabetes, physical inactivity, and obesity.

CONCLUSION

Approximately 60% of the substantial CHD mortality decline in Northern Ireland between 1987 and 2007 was attributable to major cardiovascular risk factor changes and approximately 35% was attributable to treatments. However, adverse trends in diabetes, obesity, and physical inactivity are of major concern.

Comparing Medication Adherence Methods in Lipid-Modifying Therapy

Background:

Investigators have employed a number of different methods to calculate adherence estimates for patients taking lipid-modifying therapy (LMT), including measures with different numerator and denominator options. Although at least one method is known to correlate well with cardiovascular outcomes, most have not been evaluated in outcomes studies.

Objectives:

To evaluate different methods for measuring adherence, using LMT as a case example, and to determine whether estimates for adherence differ statistically and/or whether different methods can lead to different conclusions about patient adherence.

Methods:

Adherence ratios were calculated using 8 different methods for 12,448 patients who were in a managed-care system and were considered new starts with statin therapy. The calculated measures were compared and tested for differences. Patients were categorized as adherent by each method, using a threshold of 0.8, and the proportions of patients categorized as adherent were compared for differences between adherence calculation methods.

Results:

Adherence ratios calculated with like observation intervals did not vary substantially, regardless of which method for measuring medication availability was used. Those calculated with different observation intervals had substantial variability. Mean adherence ratios ranged between 0.777 and 0.798 for difference in days' observation intervals; they ranged between 0.618 and 0.630 for the predefined interval. Differences between ratios calculated using these different denominators were statistically significant (p < 0.008). Correlations between ratios were statistically significant for all comparisons (p < 0.001). Correlation coefficients ( r) were 0.64 for comparisons between ratios with different denominators versus 1.0 for comparisons with like denominators. Categorization as adherent or nonadherent differed between the methods for about 20% of patients.

Conclusions:

Significant differences were found to be based on observation period but not on medication availability. Studies of adherence should be interpreted with caution depending on which method is used, and particular interest should be paid to whether the choice of methods is consistent with study objectives and to the observation interval, as different methods may lead to different conclusions about patient adherence. Further research in LMT and other therapeutic areas is needed to determine which methods correlate best with positive patient outcomes, such as reductions in low-density lipoprotein cholesterol and cardiovascular events.

Decline in mortality from coronary heart disease in Poland after socioeconomic transformation: modelling study

OBJECTIVES

To examine how much of the observed rapid decrease in mortality from coronary heart disease in Poland after the political, social, and economic transformation in the early 1990s could be explained by the use of medical and surgical treatments and how much by changes in cardiovascular risk factors.

DESIGN

A modelling study.

SETTING

Sources of data included controlled trials and meta-analyses, national surveys, and official statistics.

PARTICIPANTS

Population of adults aged 25-74 in Poland in 1991-2005.

MAIN OUTCOME MEASURES

Number of deaths prevented or postponed in 2005 attributable to specific treatments for coronary heart disease and changes in risk factors. A previously validated epidemiological model for coronary heart disease was used to combine and analyse data on the uptake and effectiveness of specific cardiac treatments and changes in risk factors. The observed fall in deaths from coronary heart disease from 1991 to 2005 was then partitioned among specific treatments and risk factor changes.

RESULTS

From 1991 to 2005, the death rate from coronary heart disease in Poland halved, resulting in 26,200 fewer coronary deaths in 2005 in people aged 25-74. About 37% (minimum estimate 13%, maximum estimate 77%) of this decrease was attributable to treatments, including treatments for heart failure (12%), initial treatments for acute coronary syndrome (9%), secondary prevention treatments after myocardial infarction or revascularisation (7%), chronic angina treatments (3%), and other treatments (6%). About 54% of the fall was attributed to changes in risk factors (minimum estimate 41%, maximum estimate 65%), mainly reductions in total cholesterol concentration (39%) and an increase in leisuretime physical activity (10%); however, these were partially offset by increases in body mass index (-4%) and prevalence of diabetes (-2%). Blood pressure fell in women, explaining about 29% of their decrease in mortality, but rose in men generating a negative influence (-8%). About 15% of the observed decrease in mortality was attributable to reduced smoking in men but was negligible in women.

CONCLUSIONS

Over half of the recent fall in mortality from coronary heart disease in Poland can be attributed to reductions in major risk factors and about one third to evidence based medical treatments.

Methodological issues in the assessment of diabetes treatment adherence

Improving treatment adherence in patients with diabetes remains an important objective of behavioral science research. However, progress is often limited by the heterogeneity in methods used to measure treatment adherence and difficulties in generalizing across methodologies. Various measurement methods are often used with little attention paid to questions regarding validity. Doubts about validity of adherence measurement often lead investigators to measure distal clinical outcomes instead, such as glycemic control, resulting in a loss of information. This article provides an overview of the literature on diabetes medication adherence, with a focus on measurement issues. We also consider work conducted in other chronic illnesses, particularly HIV/AIDS, that may have value in guiding future directions of diabetes medication adherence research. We highlight the need for focused investigation on how characteristics of self-report methodologies affect the validity of patient responses and conclude with practical recommendations based on the current state of the science.

Interventions to promote adherence with oral agents

OBJECTIVES

The advent of oral therapies has dramatically changed the landscape of cancer therapy. Yet the degree to which patients actually take the prescribed agents as ordered remains unknown. This article outlines the challenges that oral chemotherapy agents present to both patients and providers and suggests interventions for promoting adherence.

DATA SOURCES

Published articles and web resources.

CONCLUSION

Barriers and facilitators to medication adherence are reviewed and interventions to promote medication adherence are presented. Strategies that include patient education and symptom management can promote adherence.

IMPLICATIONS FOR NURSING PRACTICE

Maximizing adherence to oral chemotherapy agents can have many positive outcomes, but most important is improvement in overall survival and life expectancy. Other outcomes include improved safety and quality of life. Patients risk improper dosing and an increase in disease recurrence when there is nonadherence with medications. Correct dosing, education, and symptom management are all critical to ensuring adherence. Nursing interventions that incorporate education, early symptom identification, and reminder prompts can improve outcomes.

Medication adherence assessment in a clinical trial with centralized follow-up and direct-to-patient drug shipments

BACKGROUND

Assessment of adherence to study medications is a common challenge in clinical research. Counting unused study medication is the predominant method by which adherence is assessed in outpatient clinical trials but it has limitations that include questionable validity and burdens on research personnel.

PURPOSE

To compare capsule counts, patient questionnaire responses, and plasma drug levels as methods of determining adherence in a clinical trial that had 2056 participants and used centralized drug distribution and patient follow-up.

METHODS

Capsule counts from study medication bottles returned by participants and responses to questions regarding adherence during quarterly telephone interviews were averaged and compared. Both measures were compared to plasma drug levels obtained at the 3-month study visit of patients in the treatment group. Counts and questionnaire responses were converted to adherence rates (doses taken divided by days elapsed) and were categorized by stringent (≥85.7%) and liberal (≥71.4%) definitions. We calculated the prevalence-adjusted bias-adjusted kappa to assess agreement between the two measures.

RESULTS

Using a pre-paid mailer, participants returned 76.0% of study medication bottles to the central pharmacy. Both capsule counts and questionnaire responses were available for 65.8% of participants and were used to assess adherence. Capsule counts identified more patients who were under-adherent (18.8% by the stringent definition and 7.5% by the liberal definition) than self-reports did (10.4% by the stringent definition and 2.1% by the liberal definition). The prevalence-adjusted bias-adjusted kappa was 0.58 (stringent) and 0.83 (liberal), indicating fair and very good agreement, respectively. Both measures were also in agreement with plasma drug levels determined at the 3-month visit (capsule counts: p = 0.005 for the stringent and p = 0.003 for the liberal definition; questionnaire: p = 0.002 for both adherence definitions).

LIMITATIONS

Inconsistent bottle returns and incomplete notations of medication start and stop dates resulted in missing data but exploratory missing data analyses showed no reason to believe that the missing data resulted in systematic bias.

CONCLUSIONS

Depending upon the definition of adherence, there was fair to very good agreement between questionnaire results and capsule counts among returned study bottles, confirmed by plasma drug levels. We conclude that a self-report of medication adherence is potentially comparable to capsule counts as a method of assessing adherence in a clinical trial, if a relatively low adherence threshold is acceptable, but adherence should be confirmed by other measures if a high adherence threshold is required.

The predictive validity of subjective adherence measures in patients with schizophrenia

Despite frequent use of subjective adherence measures in patients with schizophrenia as well as other chronic conditions, there are several reports that question the validity of these instruments. Three well known, representative subjective measures are the Medication Adherence Questionnaire (MAQ), the Drug Attitude Inventory (DAI), and the Compliance Rating Scale (CRS). In this study we explored the predictive validity of these instruments in a European sample of 119 stabilized outpatients with schizophrenia. Clinical outcome variables were relapse and admission to a psychiatric hospital during a follow-up period of 12 months. Results indicate that the predictive validity of all three measures was poor. The MAQ was the least problematic predictor for relapse (Nagelkerke R(2)  = 0.09), and time to relapse (R(2)  = 0.07) and had the best sensitivity for relapse (63.6%) as well as admission (87.5%). The MAQ and CRS were both moderate predictive for admission (Nagelkerke R(2)  = 0.21, and R(2)  = 0.29). We conclude that the validity of the instruments studied here is questionable and have limited clinical relevance. Given the feasibility and ease of most subjective instruments, researchers may be tempted to use them but should be aware of the serious drawbacks of these instruments.

Increasing evidence-based treatments to reduce coronary heart disease mortality in Sweden: quantifying the potential gains

OBJECTIVES

Between 1986 and 2002, coronary heart disease (CHD) mortality in Sweden fell by more than 50%. Approximately one-third (4800 fewer deaths) of this decline in age-adjusted CHD mortality could be attributed to treatments in patients with CHD and primary prevention medications. High treatment levels were achieved in some cases, but in others, only 50-80% of eligible patients received appropriate therapy. We therefore examined to what extent increasing the use of specific treatments in eligible patients might have reduced CHD mortality rates in Sweden.

DESIGN AND METHODS

We used the previously validated IMPACT CHD model to combine data on CHD patient numbers, medical and surgical uptake levels and treatment effectiveness. We estimated the number of deaths prevented or postponed for 2002 (baseline scenario) and for an alternative scenario (if at least 60% of eligible patients were treated).

RESULTS

If treatments were increased to consistently cover at least 60% of eligible patients, approximately 8900 deaths could have been postponed or prevented, representing a potential gain of approximately 4100 fewer deaths than actually occurred in 2002. Approximately 45% of the 4100 gain would have come from primary prevention with statins, 23% from acute coronary syndrome treatments, 15% from secondary prevention therapies and 15% from treatments for heart failure.

CONCLUSION

Increasing the proportion of eligible patients with CHD who receive evidence-based treatment could have resulted in approximately 4100 fewer deaths in 2002, almost doubling the actual mortality reduction. These findings further emphasize the importance of aggressively identifying and treating patients with CHD and high-risk individuals.

Strategies for improving adherence to antiepileptic drug treatment in patients with epilepsy

BACKGROUND

Poor adherence to antiepileptic medications is associated with increased mortality and morbidity. In this review we focus on interventions designed to assist patients with adherence to antiepileptic medications.

OBJECTIVES

To determine the effectiveness of interventions aimed at improving adherence to antiepileptic medications in adults and children with epilepsy.

SEARCH STRATEGY

We searched the Epilepsy Group's Specialised Register (24 June 2010), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2010, Issue 2) and electronic databases: MEDLINE (OVID) (1950 to June 2010); EMBASE (OVID) (1980 to 2010 Week 24); CINAHL (1982 to June 2010) and PsycINFO (22 June 2010), and the reference lists of relevant articles. 

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials of adherence-enhancing interventions aimed at patients with clinical diagnosis of epilepsy (as defined in individual studies), of any age and of either gender, treated with antiepileptic drugs in a primary care, outpatient or other community setting.

DATA COLLECTION AND ANALYSIS

We screened titles and abstracts for eligibility. Two review authors independently extracted data and assessed each study according to the Cochrane criteria. The studies differed widely according to intervention and measures of adherence, therefore combining data was not appropriate.

MAIN RESULTS

Six trials met our inclusion criteria: five targeted adult epileptic patients with a combined patient number of 222 and one targeted parents of children with epilepsy (n = 51). Follow-up time was generally short: from one to six months. Two main types of intervention were examined: educational and behavioural modification. Each study compared treatment with no intervention 'usual care'. None compared one intervention with another. Due to heterogeneity between studies in terms of interventions and the methods used to measure adherence, we did not pool the results. Education and counselling of patients with epilepsy have shown mixed success. Behavioural interventions such as the use of intensive reminders and 'implementation intention' interventions provided more positive effects on adherence.

AUTHORS' CONCLUSIONS

Intensive reminders and 'implementation intention' interventions appear promising in enhancing adherence to antiepileptic mediations, however we need more reliable evidence on their efficacy from carefully designed randomised controlled trials before a firm conclusion can be reached.

Estimating the effect of medication adherence on health outcomes among patients with type 2 diabetes--an application of marginal structural models

OBJECTIVE

We applied marginal structural models (MSMs) to estimate the effects of medication adherence with hypoglycemics on reducing the risk of microvascular complications in type 2 diabetic patients.

METHODS

A retrospective longitudinal cohort study for type 2 diabetes patients was conducted using the California Medicaid claims database (1995-2002). Medication adherence and multiple time-varying confounders were measured quarterly over a maximum of 7.5 years follow-up. Cox regression models and MSMs results on the effect of compliance were compared.

RESULTS

Of 4708 eligible patients, 2644 (56.2%) experienced microvascular complications during the follow-up period. After controlling for baseline covariates, standard Cox models estimated that adherence was associated with increased risk of complication with hazard ratio (HR) of 1.09 (95% confidence interval (CI): 1.00, 1.18). With adjustment of time-varying confounders as exogenous variables, the HR was 0.96 (0.88, 1.04). Using the MSM technique, the HR was 0.76 (95% bootstrap CI: 0.60, 0.92), indicating a significant benefit of medication adherence with hypoglycemics on the reduction of microvascular complications. This result contrasts with the negative results obtained in the hazard model, and is more consistent with prior clinical trial results

CONCLUSION

Unlike conventional models, MSMs estimated that higher medication adherence may result in reduced risk of microvascular complications among patients with type 2 diabetes.

Coronary mortality declines in the U.S. between 1980 and 2000 quantifying the contributions from primary and secondary prevention

BACKGROUND

Coronary heart disease (CHD) mortality rates in the U.S. have halved since 1980. However, CHD remains a leading cause of death. The relative importance of secondary and primary prevention in explaining falls in coronary heart disease mortality is debated.

PURPOSE

The aim of this study was to quantify the primary and secondary preventive contributions to the U.S. CHD mortality fall between 1980 and 2000.

METHODS

The IMPACT model was used to estimate contributions to the U.S. CHD mortality fall from risk factor declines in asymptomatic individuals (primary prevention) and in CHD patients (secondary prevention). Analyses were carried out in 2008.

RESULTS

Approximately 316,100 fewer deaths were attributable to risk factor declines: 64,930 in CHD patients (21%) and 251,170 in asymptomatic individuals (79%). Smoking declines accounted for approximately 8390 fewer deaths in CHD patients and for 46,315 fewer deaths in asymptomatic people. Cholesterol falls gave approximately 22,210 fewer deaths in CHD patients and 107,300 fewer deaths in asymptomatic people. Statins accounted for approximately 16,580 fewer deaths, that is, one sixth of this mortality fall. Systolic blood pressure declines accounted for approximately 34,330 fewer deaths among CHD patients and 97,555 fewer deaths in asymptomatic individuals. Antihypertensive medications accounted for approximately 23,845 fewer deaths.

CONCLUSIONS

Half of the U.S. mortality fall in coronary heart disease between 1980 and 2000 was attributable to risk factor declines, with primary prevention producing substantially larger mortality reductions than secondary.

Medication adherence in people of culturally and linguistically diverse backgrounds: a meta-analysis

BACKGROUND

Medication adherence is of particular importance for people of culturally and linguistically diverse (CALD) backgrounds due to language difficulties, lack of social and organizational supports, lack of access to healthcare resources, and disengagement with the health-care system.

OBJECTIVE

To evaluate the impact of interventions to improve medication adherence in people of CALD backgrounds through a systematic review and meta-analysis.

METHODS

A search was performed using the following databases: Cochrane Database of Systematic Reviews, Cumulative Index to Nursing & Allied Health Literature, EMBASE, Journals@Ovid, PsychInfo, PubMed, Science Direct, Scopus, and Web of Science. Databases were searched from January 1978 to October 2009.

RESULTS

Forty-six articles reviewed were assessed as being relevant, which included 36 randomized controlled trials, 2 observational cohort studies, and 8 quasi-experimental studies. The most common method for assessing medication adherence was self-reporting measures, such as the Morisky Scale and its modifications. Few studies used combinations of adherence measures, and adherence involving a medication event monitoring system (MEMS) was used in only 6 studies. Individuals of CALD backgrounds were recruited with people of non-CALD backgrounds and subsequent analyses tended to be undertaken of the whole sample. Twenty studies showed statistically significant improvements in medication adherence, 15 of which were randomized controlled trials. Six of the successful interventions involved delivery by a bilingual person or the use of translated materials and 4 involved the use of a conceptual model. Meta-analyses demonstrated modest improvements in medication adherence.

CONCLUSIONS

Relatively little high-quality work has been conducted on adherence-enhancing interventions for people of CALD backgrounds. Greater attention needs to be given to examining the needs of specific CALD population groups. Future researchers should consider rigorously testing interventions that take into account the enormous diversity and differences that exist within any particular CALD group.

Explaining the decrease in coronary heart disease mortality in Italy between 1980 and 2000

OBJECTIVES

We examined the extent to which the decrease in coronary heart disease (CHD) mortality rates in Italy could be explained by changes in cardiovascular risk factors versus the use of medical and surgical treatments.

METHODS

We used a validated model to combine data on changes in risk factors and uptake and effectiveness of cardiac treatments among adult men and women in Italy between 1980 and 2000. Data sources included results of published trials, meta-analyses, official statistics, longitudinal studies, and national surveys. The difference between observed and expected CHD deaths in 2000 was partitioned among treatments and risk factors.

RESULTS

From 1980 to 2000, the age-adjusted CHD mortality rate in Italy fell among persons aged 25 to 84 years, resulting in 42 930 fewer CHD deaths in 2000. Approximately 40% of this decrease was attributed to treatments and 55% to changes in risk factors.

CONCLUSIONS

Over half of the CHD mortality fall in Italy between 1980 and 2000 was attributable to reductions in major risk factors, mainly cholesterol and blood pressure, and less than half to evidence-based medical therapies. These results are becoming increasingly important, both for understanding past trends and for planning future prevention and treatment strategies.

Treatment adherence impact: the systematic assessment and quantification of the impact of treatment adherence on pediatric medical and psychological outcomes

OBJECTIVE

Treatment adherence impact (TAI) is the quantification of the effects of adherence behaviors on medical or psychological outcomes using systematic assessment and analytic methods. The purpose of this review is to provide a framework for the measurement and analysis of TAI.

METHODS

Specific studies were selected from the treatment adherence literature to illustrate methods to assess TAI.

RESULTS

There are many methods available to investigators to evaluate TAI and, when possible, multiple impact outcomes should be included in adherence studies. The methods available to assess TAI and barriers to assessing TAI vary across illness group requiring illness-specific applications of the concepts presented.

CONCLUSIONS

Systematically examining TAI in adherence studies could advance the state of the art of treatment adherence science.

Potential reductions in United States coronary heart disease mortality by treating more patients

Approximately one half of the recent decline observed in age-adjusted coronary heart disease (CHD) mortality rates can be attributed to the use of modern medical and surgical interventions. In 2000, however, only about 30% to 60% of eligible patients actually received the appropriate treatment. To examine the reduction in CHD mortality potentially achievable by increasing the provision of specific medical and surgical treatment to eligible patients with CHD in the United States, we integrated the data on CHD patient numbers, medical and surgical treatment uptake levels, and treatment effectiveness using a previously validated CHD policy model. We estimated the number of deaths prevented or postponed for 2000 (baseline) and for an alternative scenario (60% of eligible patients). In 2000, the treatment levels in the United States were generally poor; only 30% to 60% of eligible patients received the appropriate therapy. These treatments resulted in approximately 159,330 fewer deaths. By treating 60% of eligible patients, 297,470 fewer deaths would have been obtained (minimum 118,360; maximum 628,120), representing 134,635 less than in 2000, with approximately 32% from heart failure therapy, 30% from secondary prevention therapy, 19% from acute coronary syndrome treatment, 15% from primary prevention with statins, 0.5% from hypertension treatment, and 1% from coronary bypass surgery for chronic angina. These findings remained stable in the sensitivity analysis. In conclusion, increasing the proportion of eligible patients with CHD who received the appropriate treatment could have achieved approximately 135,000 fewer deaths in 2000, almost doubling the benefit actually achieved. Future strategies should maximize the delivery of appropriate therapies to all eligible patients with CHD and prioritize medical therapies for secondary prevention and heart failure.

'Consumers are patients!' shared decision-making and treatment non-compliance as business opportunity

This article describes an aspect of the progressive insertion of commercial interests into the relationship between patients and their clinicians, with particular reference to psychiatry. Treatment noncompliance, a long-standing problem for healthcare professionals, has lately drawn the attention of the pharmaceutical and allied industries as a site at which to improve return on investment (ROI). Newly founded corporate ;compliance departments' and specialized consultancies that regard noncompliance as a form of marketing failure are seeking to rectify it with reinvigorated models and strategies. This intervention stands to impact patients' experience of illness as well as the participation of those formally (physicians, case managers, etc.) and informally (family, friends, etc.) involved in treatment. My analysis draws upon observation at compliance conferences to demonstrate the contrasting models of patient empowerment underlying the marketing vs. medical approaches. I propose a research agenda for measuring the effects of industry compliance programs.

Cost-effectiveness of treatments reducing coronary heart disease mortality in Ireland, 2000 to 2010

OBJECTIVE

Coronary heart disease (CHD) is associated with a large burden of disease in Ireland and is responsible for more than 6000 deaths annually. This study examined the cost-effectiveness of specific CHD treatments in Ireland.

METHODS

Irish epidemiological data on patient numbers and median survival in specific groups, plus the uptake, effectiveness, and costs of specific interventions, all stratified by age and sex, were incorporated into a previously validated CHD mortality model, the IMPACT model. This model calculates the number of life-years gained (LYGs) by specific cardiology interventions to generate incremental cost-effectiveness ratios (ICERs) per LYG for each intervention.

RESULTS

In 2000, medical and surgical treatments together prevented or postponed approximately 1885 CHD deaths in patients aged 25 to 84 years, and thus generated approximately 14,505 extra life-years (minimum 7270, maximum 22,475). In general, all the cardiac interventions investigated were highly cost-effective in the Irish setting. Aspirin, beta-blockers, ACE inhibitors, spironolactone, and warfarin for specific conditions were the most cost-effective interventions (< euro 3000/LYG), followed by the statins for secondary prevention (< euro 6500/LYG). Revascularization for chronic angina and primary angioplasty for myocardial infarction, although still cost-effective, had the highest ICER (between euro 12,000 and euro 20,000/LYG).

CONCLUSIONS

Using a comprehensive standardized methodology, cost-effectiveness ratios in this study clearly favored simple medical treatments for myocardial infarction, secondary prevention, angina, and heart failure.

Influence of disease features on adherence to prophylactic migraine medication

OBJECTIVES

Randomized controlled trials of prophylactic treatments for migraine focus on the effects in an ideal situation and underestimate the impact of non-adherence, which in this study was examined in a natural setting.

MATERIALS AND METHODS

A sample of 174 adult migraineurs with a current prescription of pharmacological prophylaxis were consecutively recruited at a specialist clinic. Logistic regression analysis was performed to analyse the association between adherence (self-reported with the Medication Adherence Report Scale) and number of years with migraine, frequency of attacks, number of days with migraine per month, attack duration, presence of cardinal features, mean intensity of pain, and recovery between attacks.

RESULTS

One third (35%) were non-adherent. Neither demographic characteristics nor any of the disease specific variables were significantly associated with adherence.

CONCLUSION

Characteristics of the disease per se did not predict non-adherence which was also observed among patients with severe migraine. The full benefit of drugs cannot be realized at currently achieved levels of adherence.

Delay in filling the initial prescription for a statin: a potential early indicator of medication nonpersistence

BACKGROUND

Identification of early predictors of medication nonpersistence may allow timely adherence-promoting interventions and potentially reduce the risk of negative health outcomes.

OBJECTIVE

This study was conducted to determine whether delay in filling an initial statin prescription predicts subsequent nonpersistence with medication.

METHODS

This observational study of a cohort of adult patients (>18 years) who newly initiated statin therapy between December 1997 and June 2000 employed data from the administrative claims database of a large US managed care organization. Patients initiating statin therapy had to have at least 18 months of continuous eligibility and no statin use in the 6-month period before the index prescription. A new measure, dispensation delay, was measured as the gap between the most recent physician or hospital visit and the fill date of the index prescription. Five categories of dispensation delay were created--no delay, 1 to 7 days, 8 to 30 days, 31 to 183 days, and >183 days. Nonpersistence was defined as a gap of >or=30 days in the statin prescription supply during the follow-up period. Cox proportional hazards regression was used to model the risk of the initial dispensation delay on the time to discontinuation, controlling for such variables as demographic characteristics, comorbidities, physician specialty, and previous health care utilization.

RESULTS

The final sample included 19,038 patients. Among all variables studied, the dispensation-delay variables were the most significant predictors of non-persistence, with a longer delay predicting a higher risk of early discontinuation. Patients with delays in filling the initial prescription of >30 days but <183 days were 30% more likely to discontinue therapy than those without delays (hazard ratio=1.30; 95% CI=1.20-1.40).

CONCLUSIONS

The delay in filling the first statin prescription significantly predicted future non-persistence. Use of this measure may allow early identification of patients at high risk for early discontinuation.

Understanding medication compliance and persistence from an economics perspective

OBJECTIVES

An increased understanding of the reasons for noncompliance and lack of persistence with prescribed medication is an important step to improve treatment effectiveness, and thus patient health. Explanations have been attempted from epidemiological, sociological, and psychological perspectives. Economic models (utility maximization, time preferences, health capital, bilateral bargaining, stated preference, and prospect theory) may contribute to the understanding of medication-taking behavior.

METHODS

Economic models are applied to medication noncompliance. Traditional consumer choice models under a budget constraint do apply to medication-taking behavior in that increased prices cause decreased utilization. Nevertheless, empiric evidence suggests that budget constraints are not the only factor affecting consumer choice around medicines. Examination of time preference models suggests that the intuitive association between time preference and medication compliance has not been investigated extensively, and has not been proven empirically. The health capital model has theoretical relevance, but has not been applied to compliance. Bilateral bargaining may present an alternative model to concordance of the patient-prescriber relationship, taking account of game-playing by either party. Nevertheless, there is limited empiric evidence to test its usefulness. Stated preference methods have been applied most extensively to medicines use.

RESULTS

Evidence suggests that patients' preferences are consistently affected by side effects, and that preferences change over time, with age and experience. Prospect theory attempts to explain how new information changes risk perceptions and associated behavior but has not been applied empirically to medication use.

CONCLUSIONS

Economic models of behavior may contribute to the understanding of medication use, but more empiric work is needed to assess their applicability.

A systematic review of interventions to improve medication taking in elderly patients prescribed multiple medications

A range of behavioural, educational and provider-focused strategies have been tested, individually or in combination, for improving medication adherence. The results of various interventions in different patient groups, including the elderly, have been subjected to systematic reviews and meta-analyses, but because most studies have focused on improving adherence to one drug or drug group, they may have limited applicability to the general elderly population who more commonly use multiple medications for multiple co-morbidities.A systematic review of controlled studies aimed at improving adherence in community-living elderly patients prescribed at least three, or a mean/median of four or more, long-term medications was undertaken. Only studies which included a minimum of 60 patients in each group, followed patients for >or=4 weeks after intervention, and measured adherence to all medications at baseline and at the conclusion of the study were considered for inclusion in the review. Eight studies met the inclusion criteria. All eight studies used verbal and/or written medication information in combination with behavioural strategies with or without provider-focused strategies. Pharmaceutical care was the theoretical framework of the interventions used in the majority of the studies. Only four studies demonstrated a significant improvement in adherence as a result of the interventions. The relative change in adherence in the intervention groups was highly variable, ranging from -13% to +55.5% (mean +11.4%). Regular scheduled patient follow-up along with a multi-compartment dose administration aid was an effective strategy for maintaining adherence in one study, while group education combined with individualized medication cards was successful in another study. Medication review by pharmacists with a focus on regimen simplification was found to be effective in two studies.Overall, as a result of inconsistent methodology and findings across the eight studies, we were unable to draw firm conclusions in favour of any particular intervention. Innovative strategies for enhancing medication adherence in the elderly and reliable measures of adherence are needed. Until further evidence from single-intervention strategies becomes available, combinations of educational and behavioural strategies should be used to improve medication adherence in the elderly.

Assessment of medication adherence in patients with schizophrenia: the Achilles heel of adherence research

Measuring medication adherence in patients with schizophrenia is difficult and lacks a gold standard. Consequently, a great number of different methods and instruments have been proposed. Although it has been assumed that they all measure medication adherence, this study demonstrates that instruments differ significantly. Using data from an international multisite study (N = 329), we found that 3 questionnaires, designed to measure medication adherence and typical for instruments used in studies in patients with schizophrenia, do not agree in labeling patients as nonadherent. Further, they seem not to measure the same trait, are related to different established risk factors of nonadherence, and are only weakly related to these established risk factors of nonadherence. If these results are representative of the validity of other measures used in adherence research, this may have serious consequences for the interpretation of, and explanations for discrepancies found in the literature. Researchers should be aware of this problem and continue to combine objective and subjective methods in the hope of increasing the reliability and validity of measures of adherence.

Reporting of adherence to medication in recent randomized controlled trials of 6 chronic diseases: a systematic literature review

BACKGROUND

International recommendations such as the CONSORT and International Conference on Harmonisation statements recognize patient adherence to prescribed treatment as an important aspect of a treatment's evaluation, but this issue is little assessed.

OBJECTIVES

To evaluate how medication adherence was assessed and reported in recently published randomized controlled trials (RCTs).

MATERIAL AND METHODS

All publications of RCTs assessing pharmacological treatments in 6 major chronic diseases published in high-impact-factor journals in 2003 and 2004 were selected from the Medline database. Two investigators analyzed how medication adherence was assessed and reported.

RESULTS

A total of 192 publications were analyzed: 71 in HIV infection, 48 diabetes mellitus, 24 rheumatoid arthritis, 23 asthma, 15 hypertension, 7 osteoporosis, and 4 about 2 of these diseases. The assessment of medication adherence was documented in 69 (35.9%) publications, by counting pill intake in half of these. Results of adherence were reported in 64 (33.3%) publications. Adherence was reported as a quantitative measure: Proportion of the treatment prescribed in 27 articles and as a qualitative measure (adherent patient, yes/no) in 41 (in 4 reports both techniques were used). When reported, the median intake of prescribed medication was 93%, and the median proportion of "nonadherent" patients was 6.2%.

CONCLUSIONS

There is important variability in the assessment and reporting of medication adherence in published RCTs of pharmacological treatments of selected chronic diseases, for a given disease and across diseases. Standardization is advisable to allow for comparisons among studies.

Predictors of medication adherence in inflammatory bowel disease

BACKGROUND AND AIMS

This study reports cross-sectional medication adherence data from year 1 of the Manitoba Inflammatory Bowel Disease (IBD) Cohort Study, a longitudinal, population-based study of multiple determinants of health outcomes in IBD in those diagnosed within 7 yr.

METHODS

A total of 326 participants completed a validated multi-item self-report measure of adherence, which assesses a range of adherence behaviors. Demographic, clinical, and psycho-social characteristics were also assessed by survey. Adherence was initially considered as a continuous variable and then categorized as high or low adherence for logistic regression analysis to determine predictors of adherence behavior.

RESULTS

Using the cutoff score of 20/25 on the Medication Adherence Report Scale, high adherence was reported by 73% of men and 63% of women. For men, predictors of low adherence included diagnosis (UC: OR 4.42, 95% CI 1.66-11.75) and employment status (employed: OR 11.27, 95% CI 2.05-62.08). For women, predictors of low adherence included younger age (under 30 versus over 50 OR 3.64, 95% CI 1.41-9.43; under 30 vs. 40-49 yr: OR 2.62, 95% CI 1.07-6.42). High scores on the Obstacles to Medication Use Scale strongly related to low adherence for both men (OR 4.05, 95% CI 1.40-11.70) and women (OR 3.89, 95% CI 1.90-7.99). 5-ASA use (oral or rectal) was not related to adherence. For women, immunosuppressant use versus no use was associated with high adherence (OR 4.49, 95% CI 1.58-12.76). Low trait agreeableness was associated with low adherence (OR 2.03, 95% CI 1.12-3.66).

CONCLUSIONS

Approximately one-third of IBD patients were low adherers. Predictors of adherence differed markedly between genders, although obstacles such as medication cost were relevant for both men and women.

The cost effectiveness of a telephone-based pharmacy advisory service to improve adherence to newly prescribed medicines

OBJECTIVE

This "proof of concept" study aimed to assess the cost effectiveness of pharmacists giving advice via telephone, to patients receiving a new medicine for a chronic condition, in England.

METHODS

The self-regulatory model (SRM) theory was used to guide development of our intervention and used in training pharmacists to adopt a patient-centred approach. Non-adherence to new medicines for chronic conditions develops rapidly so we developed a study intervention in which a pharmacist telephoned patients two weeks after they had started a new medicine for a chronic condition. Patients were included if they were 75 or older, or were suffering from stroke, cardiovascular disease, asthma, diabetes or rheumatoid arthritis, and were randomized into treatment or control arms. Main outcome measures were non-adherence and cost to the UK NHS, obtained via a questionnaire sent two months after starting therapy. Cost of the intervention was also included. Incremental cost effectiveness ratios (ICERs) were generated.

RESULTS

Five hundred patients were recruited. At 4-week follow-up, non-adherence was significantly lower in the intervention group (9% vs 16%, p=0.032). The number of patients reporting medicine-related problems was significantly lower in the intervention group compared to the control, (23% vs 34% p=0.021). Mean total patient costs at 2-month follow-up (median, range) were intervention: pound sterling 187.7 (40.6, 4.2-2484.3); control: pound sterling 282.8 (42, 0-3804) (p<0.0001). The intervention was dominant (less costly and more effective). If the decision maker is not willing to pay anything for one extra adherent patient, there is still a 90% probability that the intervention is cost effective.

CONCLUSIONS

These findings suggest that pharmacists can meet patients' needs for information and advice on medicines, soon after starting treatment. While a larger trial is needed to confirm that the effect is real and sustained, these initial findings suggest the study intervention may be effective, at least in the short term, with a reduced overall cost to the health provider.

Refill adherence for patients with asthma and COPD: comparison of a pharmacy record database with manually collected repeat prescriptions

PURPOSE

To compare refill adherence data based on two different methods of data capturing, that is, manually collected repeat prescriptions and a pharmacy record database.

METHODS

The study comprised a comparison of adherence data from manually collected repeat prescriptions of asthma and chronic obstructive pulmonary disease (COPD) drugs with fixed dosages dispensed in 2002 and the corresponding data from a pharmacy record database. Data were collected in the county of Jämtland in Sweden. Refill adherence was calculated for the different collection methods.

RESULTS

Data from 285 manually collected repeat prescriptions for asthma/COPD drugs for 2002 showed that 35% of the prescribings had been satisfactory refilled, while 42% showed an undersupply and 23% an oversupply. The pharmacy record database had 490 prescribings for asthma/COPD drugs registered in 2002, 28% of these had a satisfactory refill adherence, while 43% showed an undersupply, and 29% an oversupply. Based on the database it could be shown that 11% of the individuals had used more than one repeat prescription of the same medicine during 2002. Based on the pharmacy record database for 1999-2002, it was shown that 29% of the prescribings had been satisfactory refilled whereas undersupply increased (53%) and oversupply decreased (18%) as compared to the 1-year data.

CONCLUSIONS

Refill adherence determined from manually collected repeat prescriptions and from a pharmacy record database did not differ for a 1-year period. Four-year data might give a better overview of patients' refill adherence than 1-year data.

Explaining the decrease in U.S. deaths from coronary disease, 1980-2000

BACKGROUND

Mortality from coronary heart disease in the United States has decreased substantially in recent decades. We conducted a study to determine how much of this decrease could be explained by the use of medical and surgical treatments as opposed to changes in cardiovascular risk factors.

METHODS

We applied a previously validated statistical model, IMPACT, to data on the use and effectiveness of specific cardiac treatments and on changes in risk factors between 1980 and 2000 among U.S. adults 25 to 84 years old. The difference between the observed and expected number of deaths from coronary heart disease in 2000 was distributed among the treatments and risk factors included in the analyses.

RESULTS

From 1980 through 2000, the age-adjusted death rate for coronary heart disease fell from 542.9 to 266.8 deaths per 100,000 population among men and from 263.3 to 134.4 deaths per 100,000 population among women, resulting in 341,745 fewer deaths from coronary heart disease in 2000. Approximately 47% of this decrease was attributed to treatments, including secondary preventive therapies after myocardial infarction or revascularization (11%), initial treatments for acute myocardial infarction or unstable angina (10%), treatments for heart failure (9%), revascularization for chronic angina (5%), and other therapies (12%). Approximately 44% was attributed to changes in risk factors, including reductions in total cholesterol (24%), systolic blood pressure (20%), smoking prevalence (12%), and physical inactivity (5%), although these reductions were partially offset by increases in the body-mass index and the prevalence of diabetes, which accounted for an increased number of deaths (8% and 10%, respectively).

CONCLUSIONS

Approximately half the decline in U.S. deaths from coronary heart disease from 1980 through 2000 may be attributable to reductions in major risk factors and approximately half to evidence-based medical therapies.

What role does measuring medication compliance play in evaluating the efficacy of naltrexone?

BACKGROUND

Compliance with medication in pharmacotherapy trials of alcoholism has been shown to be equal to, or more, important than in other areas of medicine. Research has suggested that naltrexone's effectiveness can be greatly influenced by the compliance of participants in clinical trials. Presently, we compare 2 compliance measurement methods [urine riboflavin and medication event monitoring system (MEMS)] used simultaneously to evaluate naltrexone's efficacy and the impact of compliance on the size of observable treatment effects.

METHODS

One hundred and thirty-seven of 160 randomized alcoholic patients completed 12-weeks (84 days) of naltrexone or placebo and cognitive behavioral therapy (CBT) or motivational enhancement therapy (MET). Urine riboflavin was determined during study weeks 2, 6, and 12. The MEMS provided a detailed computerized record of when a participant opened their medication bottle throughout the trial. Baseline predictors of MEMS (80% openings) and urine riboflavin (>or=1,500 ng/mL by fluorimetry) compliance were examined. The effects of the treatments in the compliant participants defined by one, the other, or both methods were compared and contrasted with a previously reported intent-to-treat analysis where compliance was not taken into account.

RESULTS

Age was predictive of compliance. 105 participants were deemed compliant via urine riboflavin criteria, 87 via MEMS, and 77 when both criteria were met, with no significant differences between treatment groups. The most compliant participants showed a significant medication by therapy interaction. Those treated with naltrexone/CBT showed more abstinence days (p<0.03), less heavy drinking days (p<0.03) and less total drinks (p<0.03) than the other groups. The effect size of this interaction increased from about 0.2 in the intent-to-treat analysis, to about 0.4 to 0.5 in the compliant group analyses, with little difference between compliance measurement methods.

CONCLUSIONS

Compliance measurement does appear to influence the evaluation of the efficacy of naltrexone within the context of CBT. Treatment effect sizes approximately doubled in the most compliant individuals. Measuring compliance by either of 2 distinct methods provides approximately similar results. As compliance with naltrexone within the context of CBT has such a large impact of treatment outcome, methods of enhancing compliance during treatment should be given the utmost attention.

Feasibility of measuring compliance to annual ivermectin treatment in the African Programme for Onchocerciasis Control

The African Programme for Onchocerciasis Control (APOC) sponsors annual distribution of ivermectin to control onchocerciasis. Ivermectin should be taken annually by 65% of community members for a number of years to eliminate the disease as a public health problem. While many community coverage surveys have been undertaken during project monitoring, individual compliance could not be studied until several annual rounds of distribution had occurred. This paper reports on the efforts to determine whether adequate records could be found to enable a compliance study. A step-down process from project to district to community level was used to identify project sites where continuous ivermectin distribution up through 2004 had occurred. The first step consisted of selecting 17 of 25 projects by APOC. The second step determined adequacy of districts where distribution had occurred on a regular annual basis. Among 121 districts 58.6% undertook distribution in all 7 years. A total 852 villages were visited and community level records were found in all but three. Records showed that distribution had occurred for a minimum of five consecutive times in 429 villages, and ultimately 10 projects. While the feasibility study found an adequate number of villages to study compliance, the large number of projects, districts and villages that did not qualify for the follow-on compliance study should lead National Onchocerciasis Control Programme managers to strengthen the overall coverage and consistency of their efforts.