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

Adherence to Newly Prescribed Diabetes Medications Among Insured Latino and White Patients With Diabetes

Importance

Medication adherence is essential to diabetes care. Patient-physician language barriers may affect medication adherence among Latino individuals.

Objective

To determine the association of patient race/ethnicity, preferred language, and physician language concordance with patient adherence to newly prescribed diabetes medications.

Design, Setting, and Participants

This observational study was conducted from January 1, 2006, to December 31, 2012, at a large integrated health care delivery system with professional interpreter services. Insured patients with type 2 diabetes, including English-speaking white, English-speaking Latino, or limited English proficiency (LEP) Latino patients with newly prescribed diabetes medication.

Exposures

Patient race/ethnicity, preferred language, and physician self-reported Spanish-language fluency.

Main Outcomes and Measures

Primary nonadherence (never dispensed), early-stage nonpersistence (dispensed only once), late-stage nonpersistence (received ≥2 dispensings, but discontinued within 24 months), and inadequate overall medication adherence (>20% time without sufficient medication supply during 24 months after initial prescription).

Results

Participants included 21 878 white patients, 5755 English-speaking Latino patients, and 3205 LEP Latino patients with a total of 46 131 prescriptions for new diabetes medications. Among LEP Latino patients, 50.2% (n = 1610) had a primary care physician reporting high Spanish fluency. For oral medications, early adherence varied substantially: 1032 LEP Latino patients (32.2%), 1565 English-speaking Latino patients (27.2%), and 4004 white patients (18.3%) were either primary nonadherent or early nonpersistent. Inadequate overall adherence was observed in 1929 LEP Latino patients (60.2%), 2975 English-speaking Latino patients (51.7%), and 8204 white patients (37.5%). For insulin, early-stage nonpersistence was 42.8% among LEP Latino patients (n = 1372), 34.4% among English-speaking Latino patients (n = 1980), and 28.5% among white patients (n = 6235). After adjustment for patient and physician characteristics, LEP Latino patients were more likely to be nonadherent to oral medications and insulin than English-speaking Latino patients (relative risks from 1.11 [95% CI, 1.06-1.15] to 1.17 [95% CI, 1.02-1.34]; P < .05) or white patients (relative risks from 1.36 [95% CI, 1.31-1.41] to 1.49 [95% CI, 1.32-1.69]; P < .05). English-speaking Latino patients were more likely to be nonadherent compared with white patients (relative risks from 1.23 [95% CI, 1.19-1.27] to 1.30 [95% CI, 1.23-1.39]; P < .05). Patient-physician language concordance was not associated with rates of nonadherence among LEP Latinos (relative risks from 0.92 [95% CI, 0.71-1.19] to 1.04 [95% CI, 0.97-1.1]; P > .28).

Conclusions and Relevance

Nonadherence to newly prescribed diabetes medications is substantially greater among Latino than white patients, even among English-speaking Latino patients. Limited English proficiency Latino patients are more likely to be nonadherent than English-speaking Latino patients independent of the Spanish-language fluency of their physicians. Interventions beyond access to interpreters or patient-physician language concordance will be required to improve medication adherence among Latino patients with diabetes.

Non-steroidal anti-inflammatory drugs and blood pressure control in patients treated for hypertension: results from the Swedish primary care cardiovascular database

PURPOSE

The aim of this observational cohort study was to investigate blood pressure level and the possibility to reach target blood pressure during concomitant use of NSAID in hypertensive patients.

MATERIALS AND METHODS

From the Swedish primary care cardiovascular database (SPCCD) a cohort of 5463 patients (2007 to 2008) with at least one prescription of NSAID dispensed 6 months prior to the last blood pressure measurement were included. Clinical data were extracted from computerized medical records and linked to the Prescribed Drug Register. Multivariable logistic regression models were used for analysis.

RESULTS

Patients with NSAID usage were younger, more often female, with lower creatinine concentrations, more musculoskeletal diagnosis and less cardiovascular comorbidity compared to patients without dispensed NSAID (p < .0001 for all). Regular dose of NSAID was not associated with a decreased possibility to reach target blood pressure. A correlation between the dose of naproxen and an increase in SBP of 7 mm Hg was found. Impairment in renal function did not influence the association between blood pressure control and NSAID (p = .27).

CONCLUSION

In hypertensive patients with concomitant use of NSAID the chance to reach target blood pressure was not impaired. In intermediate and frequent users of NSAID there was a dose response relation with naproxen and SBP which was not found in diclofenac and ibuprofen.

Coming full circle in the measurement of medication adherence: opportunities and implications for health care

There is little debate that medication nonadherence is a major public health issue and that measuring nonadherence is a crucial step toward improving it. Moreover, while measuring adherence is becoming both more feasible and more common in the era of electronic information, the reliability and usefulness of various measurements of adherence have not been well established. This paper outlines the most commonly used measures of adherence and discusses the advantages and disadvantages of each that depend on the purpose for which the measure will be used. International consensus statements on definitions and guidelines for selection and use of medication adherence measures were reviewed. The quality of recommended measures was evaluated in selected publications from 2009 to 2014. The most robust medication adherence measures are often ill suited for large-scale use. Less robust measures were found to be commonly misapplied and subsequently misinterpreted in population-level analyses. Adherence assessment and measurement were rarely integrated into standard patient care practice patterns. Successful scalable and impactful strategies to improve medication adherence will depend on understanding how to efficiently and effectively measure adherence.

Depressive symptoms and adherence to cardiometabolic therapies across phases of treatment among adults with diabetes: the Diabetes Study of Northern California (DISTANCE)

OBJECTIVE

Among adults with diabetes, depression is associated with poorer adherence to cardiometabolic medications in ongoing users; however, it is unknown whether this extends to early adherence among patients newly prescribed these medications. This study examined whether depressive symptoms among adults with diabetes newly prescribed cardiometabolic medications are associated with early and long-term nonadherence.

PATIENTS AND METHODS

An observational follow-up of 4,018 adults with type 2 diabetes who completed a survey in 2006 and were newly prescribed oral antihyperglycemic, antihypertensive, or lipid-lowering agents within the following year at Kaiser Permanente Northern California was conducted. Depressive symptoms were examined based on Patient Health Questionnaire-8 scores. Pharmacy utilization data were used to identify nonadherence by using validated methods: early nonadherence (medication never dispensed or dispensed once and never refilled) and long-term nonadherence (new prescription medication gap [NPMG]: percentage of time without medication supply). These analyses were conducted in 2016.

RESULTS

Patients with moderate-to-severe depressive symptoms had poorer adherence than nondepressed patients (8.3% more patients with early nonadherence, P=0.01; 4.9% patients with longer NPMG, P=0.002; 7.8% more patients with overall nonadherence [medication gap >20%], P=0.03). After adjustment for confounders, the models remained statistically significant for new NPMG (3.7% difference, P=0.02). There was a graded association between greater depression severity and nonadherence for all the models (test of trend, P<0.05).

CONCLUSION

Depressive symptoms were associated with modest differences in early and long-term adherence to newly prescribed cardiometabolic medications in diabetes patients. Interventions targeting adherence among adults with diabetes and depression need to address both initiation and maintenance of medication use.

Comparative persistence and adherence with newer anti-hyperglycemic agents to treat patients with type 2 diabetes in the United States

OBJECTIVES

Non-adherence and non-persistence to anti-hyperglycemic agents are associated with worse clinical and economic outcomes in patients with type 2 diabetes. This study evaluated treatment persistence and adherence across newer anti-hyperglycemic agents (canagliflozin, dapagliflozin, sitagliptin, saxagliptin, linagliptin, liraglutide, or exenatide).

METHODS

This retrospective cohort study of Truven Health Analytics Marketscan databases included adult patients with type 2 diabetes whose first pharmacy claim for a newer anti-hyperglycemic agent was between February 1, 2014 and July 31, 2014. Treatment persistence and adherence were assessed for 12 months after the first claim (post-index). Persistence was defined as no gap ≥90 days between the end of one pharmacy claim and the start of the next pharmacy claim post-index. Adherence used two definitions: proportion of days covered (PDC) and medication possession ratio (MPR). Multivariable analyses of non-persistence (hazard ratios) and adherence (odds ratios) were adjusted for baseline demographics, drug cost, clinical characteristics, and other anti-hyperglycemic agents.

RESULTS

A total of 11,961 patients met all study selection criteria. Persistence rates at 12 months were significantly greater (p < 0.05 for each comparison) for canagliflozin 100 mg (61%) compared with dapagliflozin 5 mg (40%), dapagliflozin 10 mg (41%), sitagliptin (48%), saxagliptin (42%), linagliptin (52%), liraglutide (47%), exenatide (23%), and long-acting exenatide (39%). The persistence rate was greater (p < 0.05) for canagliflozin 300 mg (64%) vs canagliflozin 100 mg. Median adherence rates for canagliflozin 100 mg (MPR = 0.83; PDC = 0.79) and canagliflozin 300 mg (MPR = 0.92; PDC = 0.81) were greater than for the other index anti-hyperglycemic agents (MPR = 0.33-0.75; PDC = 0.33-0.72). Consistent results for treatment persistence and adherence were observed in multivariable analyses that were adjusted baseline characteristics.

CONCLUSIONS

Canagliflozin was associated with better treatment persistence and treatment adherence compared with other anti-hyperglycemic agents in real-world settings.

Comparison of therapy persistence for fixed versus free combination antihypertensives: a retrospective cohort study

OBJECTIVES

The aim of the study was to compare therapy persistence among patients who started with one of three drug regimens: a monotherapy, or combination therapy either as a fixed combination (ie, 'single pill') or as a free combination (ie, two separate antihypertensive agents).

DESIGN

In a secondary data analysis, we used descriptive statistics and multivariate logistic regression to measure the effect of the three therapy regimens on therapy persistence over 4 years.

SETTING

Prescription data from a large German statutory health insurance provider.

PARTICIPANTS

All patients who started with a new antihypertensive therapy in 2007 or 2008 (n=8032) were included and followed for 4 years.

PRIMARY OUTCOME MEASURE

Therapy persistence, defined as receiving a refill prescription no later than within 180 days.

RESULTS

The persistence rates after 4 years were nearly identical among patients who started with a monotherapy (40.3%) or a fixed combination of two drugs (39.8%). However, significantly more patients who started with free-drug combinations remained therapy persistent (56.4%), resulting in an OR of 2.00 (95% CI 1.6 to 2.5; p<0.0001) for free combinations versus fixed combinations. This trend was observed in all age groups and for men and women. At the end of the study period, the number of different antihypertensive agents was still similar between patients who started with a fixed combination (2.41) and patients who started with a free combination (2.28).

CONCLUSIONS

While single-pill combinations make it easier to take different drugs at once, the risk is high that these several substances are stopped at once. Therapy persistence was significantly better for patients who started with a free-drug combination without taking much fewer different antihypertensive drugs as those with a fixed combination.

Long-term use of secondary prevention medications for heart failure in Western Australia: a protocol for a population-based cohort study

INTRODUCTION

Heart failure (HF) is a chronic, debilitating and progressive disease associated with high morbidity and mortality. Evidence-based medications (EBMs) are the cornerstone of management of patients with HF. In Australia, these EBMs are subsidised by the Commonwealth Government under the Pharmaceutical Benefits Scheme. Suboptimal dispensing and non-adherence to these EBMs have been observed in patients with HF. Our study will investigate trends in dispensing patterns, as well as adherence and persistence of EBMs for HF. We will also identify factors influencing these patterns and their impact on long-term clinical outcomes.

METHODS AND ANALYSIS

This whole population-based cohort study will use longitudinal data for people aged 65-84 years who were hospitalised for HF in Western Australia between 2003 and 2008. Linked state-wide and national data will provide patient-level information on medication dispensing, medical visits, hospitalisations and death. Drug dispensing trends will be described, drug adherence and persistence estimated and the association with all-cause/cardiovascular death and hospitalisations reported.

ETHICS AND DISSEMINATION

This project has received approvals from the Western Australian Department of Health Human Research Ethics Committee and the Western Australian Aboriginal Health Ethics Committee. Results will be published in relevant cardiology journals and presented at national and international conferences.

Use of pharmacy dispensing data to measure adherence and identify nonadherence with oral hypoglycemic agents

Purpose

A framework for calculation of adherence for oral hypoglycemic agents (OHAs) based on data from health-insurance claims is available. Pharmacy dispensing data aid identification of nonadherent patients in pharmacy practices. However, use of these data for calculation of OHA adherence requires additional methodological categories. We examined the impact of different methodological choices on estimation of OHA adherence using pharmacy dispensing data.

Methods

Four methodological categories were added to the framework available to be used for adherence calculation with pharmacy dispensing data. Three adherence measures were defined to supply pharmacists with significant information on OHA use of their patients: (i) percentage of days covered by use periods of dispensed medication (PDC), (ii) mean rate of adherent patients with a PDC ≥80 % (MRAP80), and (iii) mean number of nonadherent patients (MNNP80) per pharmacy with a PDC <80 %. A basic scenario was developed from 16 methodological categories. Consequences of choices for different parameters within these categories on the scores of the three adherence measures were calculated from dispensing data between July 2013 and July 2014.

Results

Data were available for 604,500 OHA users in 1737 community pharmacies in the Netherlands. For the basic scenario, mean PDC for OHA was 88.3 %. MRAP80 was 80.3 %, which corresponded to an average of 69 nonadherent patients per pharmacy. Different choices for parameter values resulted in score variations for PDC of 85.0–91.8 %, for MRAP80 of 75.3–86.1 %, and between 49 and 92 MNNP80 per pharmacy.

Conclusion

Sixteen methodological categories specified calculation of OHA adherence based on pharmacy dispensing data. Adherence scores expressed as percentages were relatively robust to variation in parameter values, but differed substantially for the absolute numbers of nonadherent patients per pharmacy.

Electronic supplementary material

The online version of this article (doi:10.1007/s00228-016-2149-3) contains supplementary material, which is available to authorized users.

Assessing adherence to inhaled corticosteroids in asthma patients using an integrated measure based on primary and secondary adherence

PURPOSE

There are very few studies on primary adherence (i.e., first filling of a prescription) to inhaled corticosteroids (ICS) in asthma patients; two have involved children. Moreover, adherence can be overestimated when considering only secondary adherence (i.e., following the medication recommendations for a defined period) and ignoring primary adherence. We aimed thus to evaluate the real-world primary and secondary adherence to ICS and to develop an integrated primary and secondary adherence (IPSA) measure.

METHODS

From two clinical databases of pediatric and adult asthma patients, we included 198 children and 206 adults with one ICS prescription recorded in their medical chart between 2010 and 2012 and follow-up data for ≥12 months. Adherence was estimated from written prescriptions and prescription claims data. Primary adherence was defined as filling the ICS prescription at a pharmacy within 12 months. Secondary adherence was defined as the proportion of days covered (PDC) in subjects who filled their prescription at least once. The IPSA was based on the PDC with a correction factor for primary adherence.

RESULTS

Primary adherence to ICS at 12 months was 89.4 % in children and 69.4 % in adults. Secondary adherence at 12 months in children was 33.9 %, and the IPSA was 30.3 %. These values were 52.8 and 36.6 %, respectively, in adults.

CONCLUSIONS

Primary adherence to ICS is low in adults and secondary adherence is poor in children and adults. Using the PDC as a unique measure of adherence led to significant overestimation in adults; IPSA leads to more valid estimates of adherence to ICS.

Does tablet formulation alone improve adherence and persistence: a comparison of ezetimibe fixed dose combination versus ezetimibe separate pill combination?

AIMS

The aim of this study was to compare adherence and persistence in patients who add ezetimibe to statin therapy as a separate pill combination (SPC) or fixed dose combination (FDC).

METHOD

This is a retrospective cohort study of prescription data conducted in an Australian health dataset. Two cohorts were identified: those dispensed statins and subsequently ezetimibe as either SPC or FDC. We compared adherence to combination therapy using the medication possession ratio (MPR), multivariate linear and logistic regression. Persistence to initial combination medicines and any lipid-lowering therapies were analysed using Kaplan Meyer survival and Cox proportional hazards models.

RESULTS

A total of 3651 people initiated ezetimibe SPC and 5740 ezetimibe FDC. There was no significant difference in adherence with mean MPRs: ezetimibe SPC = 0.99 (95% confidence interval 0.98-1.01) and FDC = 0.97 (95% CI 0.95-0.99). One year persistence rates to initial combination medicines were ezetimibe SPC 49.1% vs. FDC 62.4%; hazard ratio (HR) = 1.81 (95% CI 1.76-1.90). However, persistence to any lipid-lowering therapy was higher in those initiating ezetimibe SPC = 84.9% vs. FDC = 76%; HR = 0.62 (95% CI 0.55-0.72). One year persistence rates to any two lipid-lowering medicines were similar: ezetimibe SPC 65.2% and FDC 65%.

CONCLUSION

In this study FDCs have little impact on either adherence or persistence to combination lipid-lowering therapy in people who have been taking statins. The benefit of higher persistence to FDCs in first episode of treatment with initial medicines is debatable as persistence to dual therapy was similar in both cohorts.

Improving risk-stratification of Diabetes complications using temporal data mining

To understand which factor trigger worsened disease control is a crucial step in Type 2 Diabetes (T2D) patient management. The MOSAIC project, funded by the European Commission under the FP7 program, has been designed to integrate heterogeneous data sources and provide decision support in chronic T2D management through patients' continuous stratification. In this work we show how temporal data mining can be fruitfully exploited to improve risk stratification. In particular, we exploit administrative data on drug purchases to divide patients in meaningful groups. The detection of drug consumption patterns allows stratifying the population on the basis of subjects' purchasing attitude. Merging these findings with clinical values indicates the relevance of the applied methods while showing significant differences in the identified groups. This extensive approach emphasized the exploitation of administrative data to identify patterns able to explain clinical conditions.

Trends in Antihypertensive Medication Discontinuation and Low Adherence Among Medicare Beneficiaries Initiating Treatment From 2007 to 2012

Low antihypertensive medication adherence is common. During recent years, the impact of low medication adherence on increased morbidity and healthcare costs has become more recognized, leading to interventions aimed at improving adherence. We analyzed a 5% sample of Medicare beneficiaries initiating antihypertensive medication between 2007 and 2012 to assess whether reductions occurred in discontinuation and low adherence. Discontinuation was defined as having no days of antihypertensive medication supply for the final 90 days of the 365 days after initiation. Low adherence was defined as having a proportion of days covered <80% during the 365 days after initiation among beneficiaries who did not discontinue treatment. Between 2007 and 2012, 41 135 Medicare beneficiaries in the 5% sample initiated antihypertensive medication. Discontinuation was stable during the study period (21.0% in 2007 and 21.3% in 2012; P-trend=0.451). Low adherence decreased from 37.4% in 2007 to 31.7% in 2012 (P-trend<0.001). After multivariable adjustment, the relative risk of low adherence for beneficiaries initiating treatment in 2012 versus in 2007 was 0.88 (95% confidence interval, 0.83-0.92). Low adherence was more common among racial/ethnic minorities, beneficiaries with Medicaid buy-in (an indicator of low income), and those with polypharmacy, and was less common among females, beneficiaries initiating antihypertensive medication with multiple classes or a 90-day prescription fill, with dementia, a history of stroke, and those who reached the Medicare Part D coverage gap in the previous year. In conclusion, low adherence to antihypertensive medication has decreased among Medicare beneficiaries; however, rates of discontinuation and low adherence remain high.

The Change in HbA1c Associated with Initial Adherence and Subsequent Change in Adherence among Diabetes Patients Newly Initiating Metformin Therapy

Introduction. Whether changes in adherence are associated with changes in HbA1c is assumed but not known. Methods. We conducted a observational study of 2,844 type 2 diabetes patients who initiated metformin as their first antihyperglycemic drug. Using HbA1c measures before, 6-12 months after, and up to 3 years after metformin initiation, we analyzed HbA1c change as a function of initial adherence and change in adherence. Results. Compared with no adherence, initial adherence of 50-79% was associated with an adjusted reduction in HbA1c of 0.45% while adherence ≥80% was associated with HbA1c reduction of 0.73%. Change from some initial adherence (1-79%) to total nonadherence was associated with 0.25% increase in HbA1c. Change from some to full adherence was associated with an HbA1c decrease of 0.15%. Those associations were accentuated among patients not in glycemic control: change from some to no adherence was associated with an HbA1c increase of 0.63% and change from some to full adherence was associated with an HbA1c decrease of 0.40%. Conclusions. Initial adherence to newly prescribed metformin therapy produces substantial HbA1c reduction. Among those with modest adherence but suboptimal glycemic control, the difference between moving to full adherence versus nonadherence results in lower HbA1c of one percentage point.

Medication Adherence Affects Risk of New Diabetes Complications

Background: Previous outcomes-based studies of adherence to diabetes medications have focused on glycemic control and are limited by questions of temporality and uncontrolled confounding. Objective: This retrospective cohort study of new oral antidiabetic medication users examined the effect of adherence on risk of incident macrovascular and microvascular complications. Methods: A nationwide integrated insurance claims and laboratory database was used to identify new oral antidiabetic medication users between January 2004 and December 2009. People with preexisting complications were excluded and the remaining cohort was followed until development of a new diabetes complication or December 2010. Medication adherence was calculated at 3-month intervals and entered as a time-dependent variable in a Cox proportional hazards model. Covariables entered in the model included patient demographics, clinical laboratory data, a medical frailty indicator and a mortality risk score from the Johns Hopkins adjusted clinical groups system, and medication use at baseline. Results: Among the 54 505 included patients, the median age was 60 years, 28 125 (52%) were men, 1447 (3%) were considered frail, the mean mortality risk score was 33.7 (±11.1), and 9793 (18%) developed a new diabetes complication. Good adherence (medication possession ratio ≥0.8) was associated with a lower risk of a new microvascular or macrovascular diabetes complication (adjusted hazard ratio = 0.96; 95% CI = 0.92-1.00; P = 0.05). Conclusions: This study design addresses limitations of previous studies and found a small but significantly lower risk of new diabetes complications associated with good adherence to oral antidiabetic medications.

Compliance with adjuvant capecitabine in patients with stage II and III colon cancer: comparison of administrative versus medical record data

We aimed to examine the frequency of treatment delays as well as the reasons and appropriateness of such delays in early stage colon cancer patients receiving adjuvant capecitabine by comparing data from pharmacy dispensing versus medical records. Patients diagnosed with stage II or III colon cancer from 2008 to 2012 and who received at least two cycle of adjuvant capecitabine were reviewed for treatment delays. Data from pharmacy dispensing and patient medical records were compared. Multivariate regression models were constructed to identify predictors of treatment delays. A total of 697 patients were analyzed: median age was 70 years (IQR 30–89), 394 (57%) were men, 598 (86%) reported Eastern Cooperative Oncology Group 0/1, and 191 (27%) had stage II disease. In this study cohort, 396 (57%) patients experienced at least 1 treatment delay during their adjuvant treatment. Upon medical record review, half of treatment delays identified using pharmacy administrative data were actually attributable to side effects, of which over 90% were considered clinically appropriate for patients to withhold rather than to continue the drug. The most prevalent side effects were hand‐foot syndrome and diarrhea which occurred in 176 (44%) and 67 (17%) patients, respectively. Multivariate analysis revealed a statistically significant association between stage and inappropriate treatment delays whereby patients with stage II disease were more likely to experience drug noncompliance (OR 1.79, 95% CI: 1.27–2.53, P < 0.001) than those with stage III disease. Compliance with adjuvant capecitabine was reasonable. Adherence ascertained from pharmacy administrative data differs significantly from that obtained from medical records.

Defining and Measuring Primary Medication Nonadherence: Development of a Quality Measure

Poor medication adherence has been increasingly recognized as a major public health issue and a priority for health care reform. Primary medication nonadherence (PMN) is a subset of this broader subject and occurs when a new medication is prescribed for a patient, but the patient does not obtain the medication, or an appropriate alternative, within an acceptable period of time after it was prescribed. It is increasingly evident that the public health problem of PMN is widespread. However, the lack of standardized definitions and measures inhibits the ability to establish the true incidence of this problem or to track changes in PMN rates over time. Given the limitations of current measures, the Pharmacy Quality Alliance (PQA) convened an expert working group to set parameters for a new industry measure. That new measure, which links electronic prescribing and pharmacy dispensing databases and was developed and approved by the PQA, is described here. PMN literature from 1990 to June 2015 is also reviewed, and existing PMN measures are summarized.

DISCLOSURES

No funding was received for this article, and the authors declare no conflicts of interest. The views expressed in this article are those of the authors alone and do not necessarily reflect those of their respective employers. Adams has received grant support from Pfizer for adherence research. Adams and Stolpe were equally involved in all aspects of study design, data collection and interpretation, and manuscript preparation.

Non-adherence with bisphosphonates among patients with osteoporosis: impact on fracture risk and healthcare cost‏

Osteoporosis-related fractures at the spine and hip have a substantial impact on mortality, morbidity, and quality of life in older adults worldwide. Adherence to bisphosphonates is essential for effective treatment and fracture prevention. Nevertheless, numerous studies from various populations and study designs clearly indicated that adherence and persistence are poor with more than 50% of patients discontinuing therapy within one year. This is primarily explained by mild adverse effects, dosing regimens, and costs. Studies have also shown that good adherence is associated with reduced osteoporosis-related and non-related healthcare costs as soon as 2 years from therapy initiation. Nonetheless, we found only little improvement in adherence rates over the years. In light of the importance of medication adherence and the limited success of previous programs, other than reducing dosing frequency, new directions should be explored to engage patients and care givers in order to improve adherence and prevent fractures.

Health Information Technology: Meaningful Use and Next Steps to Improving Electronic Facilitation of Medication Adherence

BACKGROUND

The use of health information technology (HIT) may improve medication adherence, but challenges for implementation remain.

OBJECTIVE

The aim of this paper is to review the current state of HIT as it relates to medication adherence programs, acknowledge the potential barriers in light of current legislation, and provide recommendations to improve ongoing medication adherence strategies through the use of HIT.

METHODS

We describe four potential HIT barriers that may impact interoperability and subsequent medication adherence. Legislation in the United States has incentivized the use of HIT to facilitate and enhance medication adherence. The Health Information Technology for Economic and Clinical Health (HITECH) was recently adopted and establishes federal standards for the so-called "meaningful use" of certified electronic health record (EHR) technology that can directly impact medication adherence.

RESULTS

The four persistent HIT barriers to medication adherence include (1) underdevelopment of data reciprocity across clinical, community, and home settings, limiting the capture of data necessary for clinical care; (2) inconsistent data definitions and lack of harmonization of patient-focused data standards, making existing data difficult to use for patient-centered outcomes research; (3) inability to effectively use the national drug code information from the various electronic health record and claims datasets for adherence purposes; and (4) lack of data capture for medication management interventions, such as medication management therapy (MTM) in the EHR. Potential recommendations to address these issues are discussed.

CONCLUSION

To make meaningful, high quality data accessible, and subsequently improve medication adherence, these challenges will need to be addressed to fully reach the potential of HIT in impacting one of our largest public health issues.

Systematic review of adherence rates by medication class in type 2 diabetes: a study protocol

INTRODUCTION

Treatment options for type 2 diabetes are becoming increasingly complex with people often prescribed multiple medications, and may include both oral and injectable therapies. There is ongoing debate about which drug classes provide the optimum second-line and third-line treatment options. In the real world, patient adherence and persistence determines medication effectiveness. A better understanding of adherence may help inform the choice of second-line and third-line drug classes.

METHODS AND ANALYSIS

This systematic review will compare adherence and persistence rates across the different classes of medication available to people with type 2 diabetes. It will include all identified studies comparing medication adherence or persistence between two or more glucose-lowering medications in people with type 2 diabetes. Research databases (MEDLINE, EMBASE, The Cochrane Library, The Register of Controlled Trials, PsychINFO and CINAHL) will be searched for relevant articles, using a comprehensive search strategy. All identified medication trials and observational studies will be included which compare adherence or persistence across classes of diabetes medication. The characteristics and outcomes of all the included studies will be reported along with a study quality grade, assessed using the Cochrane Risk Assessment Tool. The quality of adjustment for confounders of adherence or persistence will be reported for each study. Where multiple (n ≥ 3) studies provide compare adherence or persistence across the same 2 medication classes, a meta-analysis will be performed.

ETHICS AND DISSEMINATION

No ethics approval is required. This review and meta-analysis (where possible) will provide important information on the relative patient adherence and persistence, with the different classes of diabetes therapies. Once complete, the results will be made available by peer-reviewed publication.

TRIAL REGISTRATION NUMBER

CRD42015027865.

Adherence to alendronic or risedronic acid treatment, combined or not to calcium and vitamin D, and related determinants in Italian patients with osteoporosis

PURPOSE

Osteoporosis is a chronic disease and an important health and social burden due to its worldwide prevalence. Literature and clinical experience report incomplete adherence to the therapy. This retrospective observational study aimed at assessing the adherence to first-line antiosteoporosis drugs (AODs; reimbursed by the National Health System, according to the Italian Medicine Agency recommendation number 79), alendronate or risedronate, with or without calcium and/or vitamin D supplements, in a real, Italian clinical setting.

PATIENTS AND METHODS

Analyses were carried out on data present in the ARNO Observatory, a population-based patient-centric Italian database. From a population of 5,808,832 inhabitants with available data, a cohort of 3.3 million of patients aged ≥40 years was selected. New users of first-line AODs as monotherapy (accrual period, 2007-2009) were followed up over 3 years to assess adherence at 6, 12, and 36 months to AODs and to supplements and related determinants.

RESULTS

Approximately 40,000 new users were identified: mostly women, aged on average (standard deviation) 71±10 years. Alendronate was the most prescribed (38.2% of patients), followed by risedronate (34.9%) and alendronate with colecalciferol as a fixed-dose combination (25.8%). Adherence at the 6-month follow-up was 54%, and this constantly and significantly decreased after 1 year to 46%, and after 3 years to 33% (P<0.01). Adherence to the fixed-dose combination was higher than to plain alendronate throughout the follow-up period. Similarly, adherence to supplements constantly decreased with the duration of treatment. Women and patients aged >50 years were more likely to adhere to treatment regimen (P<0.001). The use of drugs for peptic ulcer and gastroesophageal reflux disease and of corticosteroids for systemic use were significantly associated with high adherence at different times. Polytherapy (>5 drugs), cardiovascular, and neurological therapies were significantly associated with low adherence throughout the follow-up period.

CONCLUSION

In a huge clinical practice sample, this study highlights suboptimal adherence to first-line AODs and to supplements and important determinants, such as concomitant therapies.

Understanding adherence to medications in type 2 diabetes care and clinical trials to overcome barriers: a narrative review

AIM

To identify factors affecting adherence to medications in type 2 diabetes (T2D) care and clinical trials.

BACKGROUND

Adherence to medication is associated with better patient outcomes, lower healthcare costs, and improved quality and robustness of trial data. In T2D, non-adherence to regimens may compromise glycemic, blood pressure and lipid control, which can, in turn, increase morbidity and mortality rates.

DESIGN

A literature search was performed to identify studies reporting adherence to medications and highlighting specific adherence challenges/approaches in T2D. The search was limited to clinical trials, comparative studies or meta-analyses, reported in English with a freely available abstract.

DATA SOURCE

MEDLINE (31 December 2008 to 31 December 2013).

REVIEW METHODS

Studies not reporting adherence to medications or highlighting adherence challenges/approaches in T2D, presenting only self-reported adherence or including fewer than 100 patients were excluded. Eligible reports are discussed narratively.

RESULTS

Factors identified as having a detrimental impact on adherence were smoking, depression and polypharmacy. Conversely, increased convenience (e.g. pen compared with vial and syringe; medication supplied by mail order vs. retail pharmacy) was associated with better patient adherence, as were interventions that increased patient motivation (e.g. individualized, nurse-led consultation) and education.

CONCLUSIONS

Medication adherence is influenced by complex and multifactorial issues, which can include smoking, depression, polypharmacy, convenience of obtaining and administering the medication, patient motivation and education. We recommend simplifying treatment regimens, where possible, improving provider-patient communication, and providing support and education to increase medication adherence, with a view to improving patient outcomes and clinical trial data quality.

Development and initial evaluation of the psychometric properties of self-efficacy and adherence scales for patients with a left ventricular assist device

CONTEXT

No tools exist to measure patients' self-efficacy for and adherence to the complex home-care regimen after having a left ventricular device (LVAD) implanted.

OBJECTIVE

To develop 2 new instruments, the LVAD Patient Self-Efficacy Scale (LPSES) and the LVAD Patient Home Management Adherence Scale (LPHMAS), and evaluate their psychometric properties.

METHODS

This multistage instrumentation study recruited 102 patients (77.5% men and 22.5% women) aged 20 to 82 years, predominantly from the Midwest (34.3%) and the Northeast (26.5%) regions of the United States. Main indications for LVAD were bridge-to-transplant (69.6%) and destination therapy (21.6%), with mean implant duration of 19.9 (SD, 15.5) months. Study participants completed the following instruments: LPSES, LPHMAS, General Self-Efficacy Scale (GSES), Medical Outcomes Study General Adherence (MOSGA), and Self-Care Heart Failure Index (SCHFI) confidence and maintenance subscales. Item analyses, psychometric properties including factorial and convergent validities, and internal consistency reliability were tested.

RESULTS

Factor analyses showed that the variances for the 20-item LPSES and 9-item LPHMAS were 60.2% and 53.6%, respectively. Convergent validity of the newly developed instruments was supported by the following correlations: LPSES and GSES (r = 0.34); LPSES and SCHFI-confidence (r = 0.60); LPHMAS and MOSGA (r = 0.33); LPHMAS and SCHFI-maintenance (r = 0.40). Internal consistency reliability coefficients were 0.94 (LPSES) and 0.84 (LPHMAS). Based on these data, the LPSES and LPHMAS are valid and reliable measures of self-efficacy and adherence specific for LVAD patients. Confirmatory testing is needed to further support the validity of these instruments for use in research and clinical practice.

Adherence to Antihypertensive Therapy and Elevated Blood Pressure: Should We Consider the Use of Multiple Medications?

Background

Although a majority of patients with hypertension require a multidrug therapy, this is rarely considered when measuring adherence from refill data. Moreover, investigating the association between refill non-adherence to antihypertensive therapy (AHT) and elevated blood pressure (BP) has been advocated.

Objective

Identify factors associated with non-adherence to AHT, considering the multidrug therapy, and investigate the association between non-adherence to AHT and elevated BP.

Methods

A retrospective cohort study including patients with hypertension, identified from a random sample of 5025 Swedish adults. Two measures of adherence were estimated by the proportion of days covered method (PDC≥80%): (1) Adherence to any antihypertensive medication and, (2) adherence to the full AHT regimen. Multiple logistic regressions were performed to investigate the association between sociodemographic factors (age, sex, education, income), clinical factors (user profile, number of antihypertensive medications, healthcare use, cardiovascular comorbidities) and non-adherence. Moreover, the association between non-adherence (long-term and a month prior to BP measurement) and elevated BP was investigated.

Results

Non-adherence to any antihypertensive medication was higher among persons < 65 years (Odds Ratio, OR 2.75 [95% CI, 1.18–6.43]) and with the lowest income (OR 2.05 [95% CI, 1.01–4.16]). Non-adherence to the full AHT regimen was higher among new users (OR 2.04 [95% CI, 1.32–3.15]), persons using specialized healthcare (OR 1.63, [95% CI, 1.14–2.32]), and having multiple antihypertensive medications (OR 1.85 [95% CI, 1.25–2.75] and OR 5.22 [95% CI, 3.48–7.83], for 2 and ≥3 antihypertensive medications, respectively). Non-adherence to any antihypertensive medication a month prior to healthcare visit was associated with elevated BP.

Conclusion

Sociodemographic factors were associated with non-adherence to any antihypertensive medication while clinical factors with non-adherence to the full AHT regimen. These differing findings support considering the use of multiple antihypertensive medications when measuring refill adherence. Monitoring patients' refill adherence prior to healthcare visit may facilitate interpreting elevated BP.

Impact on glycated haemoglobin of a biological response-based measure of medication adherence

AIMS

The aim of this study was to examine the relationship between a specific glycated haemoglobin (HbA1c) measurement and a pharmaceutical dispensings-based measure of adherence calculated over the 90 days before each HbA1c measure among patients who have newly initiated metformin therapy.

METHODS

We identified 3109 people with type 2 diabetes who initiated metformin as their first-ever antihyperglycaemic drug, analysing all 9918 HbA1c measurements that were taken over the next 2 years. We used an adaptation of the 'proportion of days covered' method for assessing medication adherence that corresponded to an ∼90-day interval preceding an HbA1c measurement, terming the adaptation the 'biological response-based proportion of days covered' (BRB-PDC). To account for multiple observations per patient, we analysed the association between HbA1c and BRB-PDC within the generalized estimating equation framework. Analyses were stratified by HbA1c level before metformin initiation using a threshold of 8% (64 mmol/mol).

RESULTS

After multivariable adjustment using 0% adherence as the reference category, BRB-PDC in the range 50-79% was associated with HbA1c values lower by -0.113 [95% confidence interval (CI) -0.202, -0.025] among patients with pre-metformin HbA1c <8%, and by -0.247 (95% CI -0.390, -0.104) among those with HbA1c ≥8% at metformin initiation. Full adherence (≥80%) was associated with HbA1c values lower by -0.175% (95% CI -0.257, -0.093) and by -0.453% (95% CI -0.586, -0.320).

CONCLUSIONS

Using this novel short-interval approach that more closely associates adherence with the expected biological response, the association between better adherence and HbA1c levels was considerably stronger than has been previously reported; however, the strength of the impact was dependent upon the HbA1c level before initiating metformin.

Building electronic data infrastructure for comparative effectiveness research: accomplishments, lessons learned and future steps

There are large gaps in our knowledge on the potential impact of diagnostics and therapeutics on outcomes of patients treated in the real world. Comparative effectiveness research aims to fill these gaps to maximize effectiveness of these interventions. Health information technology has the potential to dramatically improve the practice of medicine and of research. This is an overview of about US$100 million of American Recovery and Reinvestment Act investment in 12 projects managed by the Agency for Healthcare Research and Quality to build an electronic clinical data infrastructure that connects research with healthcare delivery. The achievements and lessons learned from these projects provided a foundation for the National Patient-Centered Clinical Research Network (PCORnet)and will help to guide future infrastructure development needed to build an efficient, scalable and sustainable learning health system.

An algorithm to identify medication nonpersistence using electronic pharmacy databases

OBJECTIVE

Identifying patients who are medication nonpersistent (fail to refill in a timely manner) is important for healthcare operations and research. However, consistent methods to detect nonpersistence using electronic pharmacy records are presently lacking. We developed and validated a nonpersistence algorithm for chronically used medications.

MATERIALS AND METHODS

Refill patterns of adult diabetes patients (n = 14,349) prescribed cardiometabolic therapies were studied. We evaluated various grace periods (30-300 days) to identify medication nonpersistence, which is defined as a gap between refills that exceeds a threshold equal to the last days' supply dispensed plus a grace period plus days of stockpiled medication. Since data on medication stockpiles are typically unavailable for ongoing users, we compared nonpersistence to rates calculated using algorithms that ignored stockpiles.

RESULTS

When using grace periods equal to or greater than the number of days' supply dispensed (i.e., at least 100 days), this novel algorithm for medication nonpersistence gave consistent results whether or not it accounted for days of stockpiled medication. The agreement (Kappa coefficients) between nonpersistence rates using algorithms with versus without stockpiling improved with longer grace periods and ranged from 0.63 (for 30 days) to 0.98 (for a 300-day grace period).

CONCLUSIONS

Our method has utility for health care operations and research in prevalent (ongoing) and new user cohorts. The algorithm detects a subset of patients with inadequate medication-taking behavior not identified as primary nonadherent or secondary nonadherent. Healthcare systems can most comprehensively identify patients with short- or long-term medication underutilization by identifying primary nonadherence, secondary nonadherence, and nonpersistence.

Methods for engaging stakeholders in comparative effectiveness research: a patient-centered approach to improving diabetes care

Engaging stakeholders in the research process has the potential to improve quality of care and the patient care experience. Online patient community surveys can elicit important topic areas for comparative effectiveness research. Stakeholder meetings with substantial patient representation, as well as representation from health care delivery systems and research funding agencies, are a valuable tool for selecting and refining pilot research and quality improvement projects. Giving patient stakeholders a deciding vote in selecting pilot research topics helps ensure their 'voice' is heard. Researchers and health care leaders should continue to develop best-practices and strategies for increasing patient involvement in comparative effectiveness and delivery science research.

Prevalence and Access of Secondary Source Medication Data: Evaluation of the Southeastern Diabetes Initiative (SEDI)

Medication non-adherence is a major public health issue, and measuring non-adherence is a crucial step toward improving it. A paucity of retrievable data prevents researchers from effectively measuring, tracking and sharing outcomes on medication management. High quality data derived from prescribing patterns, including behavioral and technology-based interventions, is necessary to support meaningful use, improve publicly reported quality metrics, and develop strategies to improve medication management. Electronic health records make medication data more numerous and accessible, yet the reliability and utility of electronically available data elements that reflect adherence has not been well established. We sought to explore the types of medication-related data captured over time in a series of patient encounters (n=5500) in a population-based intervention in four U.S. counties in the SouthEastern Diabetes Initiative (SEDI). The purpose was to evaluate data generated through routine healthcare delivery that are repurposed (ie, "secondary use") for research/QI/population health.

Meta-analysis of studies examining medication adherence, persistence, and discontinuation of oral antihyperglycemic agents in type 2 diabetes

OBJECTIVE

To estimate overall rates of adherence, persistence, and discontinuation for patients with type 2 diabetes mellitus (T2DM) prescribed oral antihyperglycemic agents (OAHAs) by combining results of published studies.

RESEARCH DESIGN AND METHODS

A systematic literature review was conducted to identify articles published in English over the last 10 years evaluating the use of OAHAs for the treatment of T2DM. Databases searched included PubMed/MEDLINE, EMBASE, and the Cochrane Library. Seventy studies reporting adherence, persistence or discontinuation were identified by two independent reviewers and 40 reported relevant endpoints for the analysis. Outcomes included: (1) mean adherence defined as the average medication possession ratio (MPR); (2) proportion of adherent patients (MPR ≥ 80%); (3) discontinuation; and (4) persistence. Adherence and persistence were reported in observational studies only. Discontinuation was examined separately in randomized controlled trials (RCTs) and observational studies. Meta-analyses were conducted using both fixed and random effects models. When meta-analysis was not appropriate for a given outcome, descriptive statistics were provided.

RESULTS

The pooled mean MPR (95% confidence interval [CI]) was 75.3% (68.8%-81.7%; n = 13) and the proportion of adherent patients (95% CI) was 67.9% (59.6%-76.3%; n = 12). The discontinuation rate (95% CI) in RCTs was 31.8% (17.0%-46.7%; n = 7). Persistence and discontinuation were not assessed via meta-analysis for observational studies due to the limited number of available studies and differences in outcome definitions. In these studies, persistence estimates ranged from 41.0% to 81.1%, with a mean (95% CI) of 56.2% (46.1%-66.3%; n = 6), while discontinuation estimates ranged from 9.9% to 60.1%, with a mean (95% CI) of 31.4% (17.6%-45.3%; n = 6).

LIMITATIONS

Limitations include (1) the use of MPR as a proxy for adherence, (2) limited number of studies available, and (3) observed heterogeneity.

CONCLUSION

The results of the analysis demonstrate that medication adherence, persistence, and discontinuation rates are suboptimal in patients with T2DM prescribed OAHAs.

Interventions aimed at improving performance on medication adherence metrics

BACKGROUND

medication adherence is one determining factor of treatment success. Poor medication adherence mitigates optimum clinical benefits and increases total health care costs. Current evidence suggests that for population-based adherence interventions to be effective, a multidisciplinary, multifactorial approach that can be tailored for each individual should be adopted. In the United States, national organizations such as the National Committee for Quality Assurance and the Centers for Medicare and Medicaid Services include medication adherence as a metric of health care system performance Aim of the

COMMENTARY

This article provides an overview of efforts at Kaiser Permanente Colorado to impact medication adherence-related metrics. Described interventions are supported by electronic data gathering processes with an emphasis on the role of pharmacists.

Development of an electronic medical record based alert for risk of HIV treatment failure in a low-resource setting

Background

The adoption of electronic medical record systems in resource-limited settings can help clinicians monitor patients' adherence to HIV antiretroviral therapy (ART) and identify patients at risk of future ART failure, allowing resources to be targeted to those most at risk.

Methods

Among adult patients enrolled on ART from 2005–2013 at two large, public-sector hospitals in Haiti, ART failure was assessed after 6–12 months on treatment, based on the World Health Organization's immunologic and clinical criteria. We identified models for predicting ART failure based on ART adherence measures and other patient characteristics. We assessed performance of candidate models using area under the receiver operating curve, and validated results using a randomly-split data sample. The selected prediction model was used to generate a risk score, and its ability to differentiate ART failure risk over a 42-month follow-up period was tested using stratified Kaplan Meier survival curves.

Results

Among 923 patients with CD4 results available during the period 6–12 months after ART initiation, 196 (21.2%) met ART failure criteria. The pharmacy-based proportion of days covered (PDC) measure performed best among five possible ART adherence measures at predicting ART failure. Average PDC during the first 6 months on ART was 79.0% among cases of ART failure and 88.6% among cases of non-failure (p<0.01). When additional information including sex, baseline CD4, and duration of enrollment in HIV care prior to ART initiation were added to PDC, the risk score differentiated between those who did and did not meet failure criteria over 42 months following ART initiation.

Conclusions

Pharmacy data are most useful for new ART adherence alerts within iSanté. Such alerts offer potential to help clinicians identify patients at high risk of ART failure so that they can be targeted with adherence support interventions, before ART failure occurs.

A 2014 medical informatics perspective on clinical decision support systems: do we hit the ceiling of effectiveness?

OBJECTIVE

To summarize recent research and propose a selection of best papers published in 2013 in the field of computer-based decision support in health care.

METHOD

Two literature reviews were performed by the two section editors from bibliographic databases with a focus on clinical decision support systems (CDSSs) and computer provider order entry in order to select a list of candidate best papers to be peer-reviewed by external reviewers.

RESULTS

The full review process highlighted three papers, illustrating current trends in the domain of clinical decision support. The first trend is the development of theoretical approaches for CDSSs, and is exemplified by a paper proposing the integration of family histories and pedigrees in a CDSS. The second trend is illustrated by well-designed CDSSs, showing good theoretical performances and acceptance, while failing to show a clinical impact. An example is given with a paper reporting on scorecards aiming to reduce adverse drug events. The third trend is represented by research works that try to understand the limits of CDSS use, for instance by analyzing interactions between general practitioners, patients, and a CDSS.

CONCLUSIONS

CDSSs can achieve good theoretical results in terms of sensibility and specificity, as well as a good acceptance, but evaluations often fail to demonstrate a clinical impact. Future research is needed to better understand the causes of this observation and imagine new effective solutions for CDSS implementation.

Associations between antidepressant adherence and shared decision-making, patient-provider trust, and communication among adults with diabetes: diabetes study of Northern California (DISTANCE)

BACKGROUND

Depression and adherence to antidepressant treatment are important clinical concerns in diabetes care. While patient-provider communication patterns have been associated with adherence for cardiometabolic medications, it is unknown whether interpersonal aspects of care impact antidepressant medication adherence.

OBJECTIVE

To determine whether shared decision-making, patient-provider trust, or communication are associated with early stage and ongoing antidepressant adherence.

DESIGN

Observational new prescription cohort study.

SETTING

Kaiser Permanente Northern California.

PATIENTS

One thousand five hundred twenty-three adults with type 2 diabetes who completed a survey in 2006 and received a new antidepressant prescription during 2006-2010.

MEASUREMENTS

Exposures included items based on the Trust in Physicians and Interpersonal Processes of Care instruments and the Consumer Assessment of Healthcare Providers and Systems (CAHPS) communication scale. Measures of adherence were estimated using validated methods with physician prescribing and pharmacy dispensing data: primary non-adherence (medication never dispensed), early non-persistence (dispensed once, never refilled), and new prescription medication gap (NPMG; proportion of time without medication during 12 months after initial prescription).

RESULTS

After adjusting for potential confounders, patients' perceived lack of shared decision-making was significantly associated with primary non-adherence (RR = 2.42, p < 0.05), early non-persistence (RR = 1.34, p < 0.01) and NPMG (estimated 5% greater gap in medication supply, p < 0.01). Less trust in provider was significantly associated with early non-persistence (RRs 1.22-1.25, ps < 0.05) and NPMG (estimated NPMG differences 5-8%, ps < 0.01).

LIMITATIONS

All patients were insured and had consistent access to and quality of care.

CONCLUSIONS

Patients' perceptions of their relationships with providers, including lack of shared decision-making or trust, demonstrated strong associations with antidepressant non-adherence. Further research should explore whether interventions for healthcare providers and systems that foster shared decision-making and trust might also improve medication adherence.

Initial persistence with antihypertensive therapies is associated with depression treatment persistence, but not depression

The purpose of this study was to examine the relationship between the presence of clinical depression and persistence to drug therapy treatment for depression with early nonpersistence to antihypertensive therapies in a large, diverse cohort of newly treated hypertension patients. Using a hypertension registry at Kaiser Permanente Northern California, the authors conducted a retrospective cohort study of 44,167 adults (18 years and older) with hypertension who were new users of antihypertensive therapy in 2008. We used multivariate logistic regression analysis to model the relationships between the presence of clinical depression and early nonpersistence (defined as failing to refill the first prescription within 90 days after the end of the first fill days' supply) to antihypertensive therapies, controlling for sociodemographic and clinical risk factors. Within the group of 1484 patients who had evidence of clinical depression in the 12 months prior to the initiation of antihypertensive therapy, the authors examined the relationship between drug therapy treatment for depression and 6-month persistence with antidepressant therapy with early nonpersistence with antihypertensive therapies. No association was found between the presence of clinical depression and early nonpersistence to antihypertensive therapies after adjustment for individual demographic and clinical characteristics and neighborhood-level socioeconomic status. However, among the subset of 1484 patients with documented evidence of clinical depression in the 12 months prior to the initiation of antihypertensive therapy, being prescribed and persistence with antidepressant therapy was strongly associated with lower odds of early nonpersistence to antihypertensive medications (odds ratio, 0.64; confidence interval, 0.42-0.96). In an integrated delivery system, the authors found that treatment for depression was associated with higher levels of antihypertensive persistence. Improving quality of depression care in patients with comorbid hypertension may be an important strategy in decreasing cardiovascular disease risk in these patients.

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

PURPOSE

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

APPROACH

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

CONCLUSIONS

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