Accuracy of indirect measures of medication compliance in hypertension

Nonadherence to antiasthmatic medications and its predictors among asthmatic patients in public hospitals of Bahir Dar City, North West Ethiopia: using ASK-12 tool

BACKGROUND

Globally, adequate asthma control is not yet achieved. The main cause of uncontrollability is nonadherence to prescribed medications.

OBJECTIVES

The objective of this study is to assess asthmatic patients' non-adherence to anti-asthmatic medications and the predictors associated with non-adherence.

METHODS

An institution-based cross-sectional study was conducted in three governmental hospitals in Bahir Dar city from September 5 to December 12, 2021. The data was collected using the Adherence Starts with Knowledge-12 tool (ASK-12). Systematic random sampling was applied to select study participants. Bivariable and multivariable logistic regression analyses were used to identify predictors of non-adherence. All statistical tests were analyzed using STATA version 16. P-values less than 0.05 were considered statistically significant.

RESULTS

A total of 422 asthmatic patients were included in the study. Most of the study participants (55.4%) did not adhere to their prescribed anti-asthmatic medicines. The educational status of the study participants (AOR = 0.03, 95% CI = 0.00-0.05), family history of asthma (AOR = 0.13, 95% CI = 0.04-0.21), and disease duration that the patients were living with (AOR = 0.01, 95% CI = 0.00-0.01) were the predictors of non-adherence to anti-asthmatic medications.

CONCLUSIONS

The level of nonadherence to treatment among patients with asthma was high. Religion, educational status of study participants, family history of asthma, and duration of the disease were the predictors of non-adherence of asthmatic patients to their antiasthmatic medications. Therefore, the Ministry of health, health policy makers, clinicians, and other healthcare providers should pay attention to strengthening the adherence level to antiasthmatic medications, and country-based interventions should be developed to reduce the burden of non-adherence to anti-asthmatic medications.

Impact of Design on Patient Participation in Healthcare in a Rural Health Clinic in Appalachia: A Qualitative Pilot Study

Objectives:

A pilot study exploring how elderly patients of a rural outpatient health clinic in Appalachia perceive design elements of the facility as imposing barriers to healthcare participation.

Background:

Outpatient clinics play a critical role in the delivery of healthcare in rural settings in Appalachia. While the concept of patient participation in healthcare does not enjoy a widely adopted, standardized definition, it is believed that patients who are more actively engaged in their healthcare will potentially realize improved health outcomes. This study examines the role facility design could play in participation.

Methods:

A pilot qualitative study was conducted involving focus groups with a targeted elderly population of a rural outpatient clinic in southern West Virginia. The goal was to assess the perceptions of impacts of clinical design elements on participation.

Results:

Patients identified and characterized 10 design-related elements they felt impacted participation.

Conclusions:

The design of the outpatient clinic has the potential to impact the level of engagement of patients in the healthcare process, thus providing another leverage point for improving population health in rural settings.

Development of the Purposeful Action Medication-Taking Questionnaire

This three-phase study describes the development and psychometric properties of the Medication-Taking Questionnaire (MTQ) to measure the purposeful action domain (reasons individuals decide to accept medication treatment) in the medication adherence model for hypertension. During Phase I, items were evaluated for content validity and clarity. Item analysis, internal consistency, and exploratory factor analysis were preformed during Phase II to finalize the MTQ: Purposeful Action as 12 items and 2 subscales (treatment benefits and medication safety). Phase III evaluated the MTQ: Purposeful Action for temporal stability and construct validity. The final version MTQ: Purposeful Action demonstrated good internal consistency, temporal stability, and construct validity. The MTQ: Purposeful Action appears to have good psychometric characteristics that represent the decision-making process for adherence in medication treatment for hypertension.

The Oxford Implementation Index: a new tool for incorporating implementation data into systematic reviews and meta-analyses

OBJECTIVES

This article presents a new tool that helps systematic reviewers to extract and compare implementation data across primary trials. Currently, systematic review guidance does not provide guidelines for the identification and extraction of data related to the implementation of the underlying interventions.

STUDY DESIGN AND SETTING

A team of systematic reviewers used a multistaged consensus development approach to develop this tool. First, a systematic literature search on the implementation and synthesis of clinical trial evidence was performed. The team then met in a series of subcommittees to develop an initial draft index. Drafts were presented at several research conferences and circulated to methodological experts in various health-related disciplines for feedback. The team systematically recorded, discussed, and incorporated all feedback into further revisions. A penultimate draft was discussed at the 2010 Cochrane-Campbell Collaboration Colloquium to finalize its content.

RESULTS

The Oxford Implementation Index provides a checklist of implementation data to extract from primary trials. Checklist items are organized into four domains: intervention design, actual delivery by trial practitioners, uptake of the intervention by participants, and contextual factors. Systematic reviewers piloting the index at the Cochrane-Campbell Colloquium reported that the index was helpful for the identification of implementation data.

CONCLUSION

The Oxford Implementation Index provides a framework to help reviewers assess implementation data across trials. Reviewers can use this tool to identify implementation data, extract relevant information, and compare features of implementation across primary trials in a systematic review. The index is a work-in-progress, and future efforts will focus on refining the index, improving usability, and integrating the index with other guidance on systematic reviewing.

Resistant hypertension? Assessment of adherence by toxicological urine analysis

OBJECTIVE

Uncontrolled hypertension under antihypertensive multidrug regimen is not necessarily always true resistance. Incomplete adherence is one of several possible causes of uncontrolled hypertension. Nonadherence remains largely unrecognized and is falsely interpreted as treatment resistance, as it is difficult to confirm or exclude objectively. This is the first study assessing adherence in patients with apparent resistant hypertension systematically via toxicological urine screening.

METHODS

All patients referred from primary care physicians because of uncontrolled hypertension between 2004 and 2011 were analysed. Adherence was assessed in all patients with uncontrolled hypertension despite the concurrent use of at least four antihypertensive agents by using liquid chromatography-mass spectrometry analysis for antihypertensive drugs or their corresponding metabolites in urine.

RESULTS

A total of 375 patients with uncontrolled hypertension were referred. After optimization of drug therapy and exclusion of white coat hypertension, 108 patients met criteria for resistant hypertension. Of those, 15 patients had secondary causes of hypertension and 17 achieved goal blood pressure with quadruple antihypertensive therapy. Of the remaining 76 patients, 40 patients (53%) were found to be nonadherent. Among nonadherent patients, 30% had complete and 70% had incomplete adherence; 85% of the latter had taken less than 50% of drugs prescribed. Lack of adherence was almost evenly distributed between different classes of antihypertensive drugs.

CONCLUSION

Low adherence was the most common cause of poor blood pressure control in patients with apparent resistant hypertension, being twice as frequent as secondary causes of hypertension. Incomplete adherence was far more common than complete nonadherence; thus, assessment of adherence in patients on multiple drug regime is only reliable when all drugs are included in assessment. Assessing adherence by toxicological urine screening is a useful tool in detecting low adherence, especially in the setting of multidrug regimen as a cause of apparently resistant hypertension.

Long-run health effects of cost-related non-adherence to prescribed medications among adults in late midlife

Objectives

Sub-optimal adherence to prescribed medications due to cost is known to have adverse health effects over 2–4 years, but little is known about its longer run effects. Here we quantify whether and how cost-related non-adherence (CRN) influences the risk of adverse health events over a 10-year period.

Methods

Nationally representative 1994–2004 data from the Health and Retirement Study, conducted by the US University of Michigan, are analyzed for 2460 adults aged 50–59 years in 1994 who were regularly taking medication(s) and had one or more chronic health conditions at baseline (hypertension, heart disease, diabetes, cancer, lung problems, arthritis or had experienced a heart attack or stroke). Regression models are estimated to quantify CRN's effects on the risk of four different adverse health events, paying careful attention to the potential endogeneity of CRN.

Key findings

Patients who underused medication(s) due to cost are significantly more likely to see new chronic conditions emerge, to be hospitalized, to experience a heart attack or stroke and to see problems develop limiting their ability to work. We also find the more frequent the CRN, the more probable each of these outcomes.

Conclusions

Adults in late midlife with chronic conditions who underuse medications for cost reasons place themselves at much higher risk for serious adverse events over the long run.

Medication adherence among ambulatory patients with type 2 diabetes in a tertiary healthcare setting in southwestern Nigeria

OBJECTIVE

To assess adherence to medication among ambulatory patients with type 2 diabetes, ascertain the level of glycemic control, and evaluate patients' opinions on probable reasons for non-adherence with a view to identify areas of intervention to improve adherence.

METHODS

A prospective cross-sectional study was carried out at a 900-bed tertiary teaching hospital in Ibadan, Southwestern Nigeria between June and August, 2009. Out of 140 consented patients, 114 (81.4%) properly responded to the validated and pre-tested data collection tool and these were subsequently considered for analysis. Descriptive statistics were used to summarize the data. Means and proportions were compared using student t-test and chi-square or Kruskal-Wallis test as appropriate, with p<0.05 considered statistical significant.

RESULTS

Approximately sixty percent of the patients were adjudged adherent with prescribed medication. Out of 58.8% of the cohort who gave their recent fasting plasma glucose (FPG) values, 59.7% had FPG above 110mg/dL. The mean FPG for patients was 139.05 (SD=70.5)mg/dL, males and females significantly differed in their mean FPG, 146.55 (SD=85.0)mg/dL versus 133.33 (SD=57.6)mg/dL respectively (p=0.032). Also, the mean FPG values for adherent patients, 137.09 (SD=59.3)mg/dL was lower than their non-adherent counterparts, 143.92 (SD=87.6) mg/dL, but the difference was not statistically significant (p=0.095). Financial constraint (34.4%) was the major barrier to optimal adherence with medication. A significant association exist between genders and opinions on physician's mode of approach during patient-physician interaction as a contributory factor for non-adherence (p=0.038).

CONCLUSIONS

Medication adherence of ambulatory type 2 diabetes patients is considerable. However, the relatively high level of adherence did not appear to have significantly impacted on patients' glycemic status due to a substantial number who had plasma glucose above the recommended targets. Multiple methods may be required to detect patient who report adherence but who may in fact be non-adherent. Also, adherence to other aspects of diabetes management plan needs to be encouraged in order to accomplish optimal glycemic control. Initiatives targeting patient-specific intervention to improve medication adherence should be considered.

The eight-item Morisky Medication Adherence Scale MMAS: translation and validation of the Malaysian version

AIMS

To translate and examine the psychometric properties of the Malaysian version of the Morisky Medication Adherence Scale (MMAS) among patients with type 2 diabetes.

METHODS

A standard "forward-backward" procedure was used to translate MMAS into Malay language. It was later validated on a convenience sample of 223 type 2 diabetes outpatients between May and September 2009. Reliability was tested for internal consistency. Validity was confirmed using convergent and known group validity.

RESULTS

Employing the recommended scoring method, the mean±SD of MMAS scores was 6.13±1.72. Moderate internal consistency was found (Cronbach's α=0.675), the test-retest reliability value was 0.816 (p<0.001). A positive correlation between the eight- and four-item MMAS was found (r=0.792; p<0.01). A significant relationship between MMAS categories and HbA1c categories (χ(2)=20.261; p≥0.001) was found. The MMAS sensitivity and specificity, with positive and negative predictive values were 77.61%, 45.37%, 46.84% and 76.56%, respectively.

CONCLUSIONS

The findings of this validation study indicate that the Malaysian version of the MMAS is a reliable and valid measure of medication adherence which can now be used.

A comparison of adherence assessment methods utilized in the United States: perspectives of researchers, HIV-infected children, and their caregivers

This study sought to elucidate methodological issues in adherence research by comparing multiple methods of assessing adherence to antiretroviral medication. From 2003 to 2004, 24 youths with vertically infected HIV disease (mean age = 14.0 years; range, 8-18) and their caregivers participated in a 6-month study. These children were all on highly active antiretroviral therapy (HAART) and were relatively healthy (mean CD4 absolute count = 711.8 +/- 604.5). Adherence was assessed with the Medication Event Monitoring System (MEMS), pill counts, and interviews. Patients and caregivers completed the Perceptions of Adherence Study Participation (PASP) questionnaire. MEMS provided the most detailed adherence information, and good reliability was indicated by significant correlations with medical markers. Pill counts provided similar adherence rates, while patients and caregivers reported nearly perfect adherence in interviews. Problems were experienced with each method: MEMS were expensive, had cap malfunctions, and lack a consistent guiding principle for data interpretation. With pill counts, families forgot to bring all medication bottles to clinic, and interviews were compromised by social desirability and difficulty reaching families by telephone. Most patients and caregivers believed study participation improved the child's adherence, although PASP ratings were unrelated to adherence at the study endpoint. While MEMS may be most reliable, pill counts offer comparable data and are less costly, while interviews seemed least accurate in this study. Most participants reported positive perceptions of their research experience. A consensus among researchers is needed for defining and measuring adherence, and specific recommendations are offered for achieving this goal.

Determinants of poor adherence in hypertensive patients: development and validation of the "Maastricht Utrecht Adherence in Hypertension (MUAH)-questionnaire"

OBJECTIVES

(1) To help identify patients with poor adherence and (2) to identify potential reasons that impede or facilitate adherence.

METHODS

Seventeen patients who used antihypertensive drugs participated in semi-standardized interviews. Interviews were recorded and reviewed by two investigators. Forty-four items were selected. An exploratory factor analysis was performed. Convergent validity was assessed by evaluating the association between sum scores on the identified subscales and three other adherence measures: (1) the Brief Medication Questionnaire (BMQ), (2) pharmacy refill records and (3) electronic monitoring. Regression analysis was used to evaluate the magnitude of associations.

RESULTS

Two hundred and fifty-five (90%) patients completed the questionnaire. Factor analysis resulted in a four-factor solution, explaining 30% of cumulative variance among respondents. The factors (scales) were labeled: positive attitude towards health care and medication (I), lack of discipline (II), aversion towards medication (III) and active coping with health problems (IV). Chronbach's alpha coefficient was 0.75, 0.80, 0.63 and 0.76 for scales I, II, III and IV, respectively. Convergent validity was partly supported by statistically significant associations that were found between sum scores of subscales 1 and II and the BMQ and electronic monitoring, respectively.

CONCLUSION

The MUAH-questionnaire has excellent psychometric properties and may be useful to identify factors that impede or facilitate adherence. However, it is not clear to what extent the questionnaire measures actual adherence.

PRACTICE IMPLICATIONS

Validation of the MUAH-questionnaire in other studies is needed.

Measurement, Correlates, and Health Outcomes of Medication Adherence Among Seniors

OBJECTIVE

To provide a comprehensive review of the literature on the measurement, correlates, and health outcomes of medication adherence among community-dwelling older adults.

DATA SOURCES

Searches of MEDLINE, PubMed, and International Pharmaceutical Abstracts databases for English-language literature (1966–December 2002) were conducted using one or more of the following terms: elderly, adherence/nonadherence, compliance/noncompliance, medication/drug, methodology/measurement, and hospitalization.

STUDY SELECTION AND DATA EXTRACTION

From the above search, studies of medication adherence in community-dwelling seniors were selected for review along with relevant publications from the reference lists of articles identified in the initial database search.

DATA SYNTHESIS

Although several methods are available for the assessment of adherence, accurate measurement continues to be difficult. The available evidence suggests that polypharmacy and poor patient–healthcare provider relationships (including the use of multiple providers) may be major determinants of nonadherence among older persons, with the impact of most sociodemographic factors being negligible. There is little consensus regarding other determinants of nonadherence. Relatively few high-quality investigations have examined the associations between nonadherence and subsequent health outcomes. Available data provide some support for increased health risks with nonadherence. However, interventions to improve adherence have seldom demonstrated positive effects on health outcomes.

CONCLUSIONS

There are few empirical data to support a simple systematic descriptor of the nonadherent patient. The inconsistencies across studies may be attributable, in part, to the inherent difficulties involved in the measurement of a behavioral risk factor such as nonadherence. Future research in this area would be strengthened by incorporation of detailed assessments of patient-reported reasons for nonadherence, the appropriateness of drug regimens, and the effect of nonadherence on health outcomes.

Provider assessment of adherence to HIV antiretroviral therapy

BACKGROUND

Adherence assessment is an essential component of monitoring HIV antiretroviral therapy. Prior studies suggest that medical providers frequently estimate individual patient adherence inaccurately.

OBJECTIVE

We compared provider estimates of nonadherence to antiretroviral therapy with unannounced pill counts and structured patient interviews to determine the accuracy of adherence information obtained by providers and patients.

DESIGN, SETTING, AND PARTICIPANTS

Comparison of three adherence measures in homeless or marginally housed persons receiving HIV antiretroviral therapy (n = 45) and their providers (n = 35).

MEASUREMENTS

Provider estimate of percentage of pills taken; three successive patient structured reports of number of doses missed in the last 3 days; and three successive unannounced pill counts.

RESULTS

13% (95% confidence interval [CI], 4%-22%) of patients were not following their regimen as directed. Provider-adherence estimate explained only 26% (95% CI, 6%-47%) of the variation in pill count adherence, whereas patient report explained 72% (95% CI, 52%-96%). The sensitivity and specificity of provider estimates of nonadherence, defined as <80% of pills taken by pill count, were 40% and 85%, respectively. The sensitivity and specificity of patient interview were 72% and 95%, respectively.

CONCLUSIONS

Provider estimate of adherence was inaccurate whereas structured patient report was more closely related to pill count. Structured assessment over several short intervals may improve accuracy of adherence assessment in clinical practice.

Methods for measuring and monitoring medication regimen adherence in clinical trials and clinical practice

Researchers and clinicians have used numerous methods in their attempts to adequately assess patient compliance (adherence) with medication regimens and to identify noncompliant patients. Large variations have been reported in the extent of noncompliance in individual patients and large populations. In addition, nonadherence has often been poorly defined. Direct measures of adherence include drug assays of blood or urine, use of drug markers with the target medication, and direct observation of the patient receiving the medication. Indirect measures of adherence imply that the medication has been used by the patient; these measures include various forms of self-reporting by the patient, medication measurement (pill count), use of electronic monitoring devices, and review of prescription records and claims. Compliance measures should be assessed on the basis of their validity (sensitivity and specificity or statistical correlation) and the reference standard used. Many early studies used pill counts as a reference standard, but electronic monitoring devices such as the Medication Event Monitoring System have replaced pill counts as the reference standard. The choice of a method for measuring adherence to a medication regimen should be based on the usefulness and reliability of the method in light of the researcher's or clinician's goals. Specific methods may be more applicable to certain situations, depending on the type of adherence being assessed, the precision required, and the intended application of the results.

The Brief Medication Questionnaire: a tool for screening patient adherence and barriers to adherence

Self-report tools for monitoring adherence can be useful in identifying patients who need assistance with their medications, assessing patient concerns, and evaluating new programs. The aim of this study is to test the validity of the Brief Medication Questionnaire (BMQ), a new self-report tool for screening adherence and barriers to adherence. The tool includes a 5-item Regimen Screen that asks patients how they took each medication in the past week, a 2-item Belief Screen that asks about drug effects and bothersome features, and a 2-item Recall Screen about potential difficulties remembering. Validity was assessed in 20 patients using the Medication Events Monitoring System (MEMS). Results varied by type of non-adherence, with the Regimen and Belief Screens having 80-100% sensitivity for "repeat" non-adherence and the Recall Screen having 90% sensitivity for "sporadic" non-adherence. The BMQ appears more sensitive than existing tools and may be useful in identifying and diagnosing adherence problems.

Patient self-administration of medication: a review of the literature

The purpose of this review was to critically examine the literature published in the English language (1983-1995) related to the use of self-medication programmes by hospital patients and to determine whether such a scheme could be implemented and evaluated within the acute medical setting. Searches revealed a wealth of information relating to self-medication and it was evident that such schemes have been welcomed with enthusiasm by clinical nurses. However, only 12 empirical studies evaluating the advantages and disadvantages of self-medication programmes could be located. The remainder were all anecdotal or described the process of implementation in such broad terms that they could not be considered to fulfil the rigorous requirements demanded of research studies. Even the 12 empirical studies contained serious methodological flaws. Thus authors' claims that self-medication increased compliance with the drug regime could not be accepted with confidence. Nevertheless, the authors made a number of sensible recommendations which logically would be expected to increase compliance. These included simplification of the drug regime and careful patient assessment with the programme tailored to meet individual need. It was also possible to highlight areas where future research could be conducted (e.g. more detailed examination of the importance nurse-patient interaction to the success of self-medication, longer-term evaluation) and to identify means of improving research designs so that this important field of patient care may in future be examined with greater rigour.

Cognitive impairment and medication adherence

1. The findings of this study are congruent with previous work that found that subjects' knowledge about medication is not necessarily correlated with adherence to medication regimens. 2. The nature and experience of forgetting medications merits further investigation. Asking patients about forgetting medication is easy to do, and many methods of compensating for forgetfulness are available. 3. Cognitive impairment was not associated with medication adherence. Cognitively impaired elders were likely to have caregivers assisting in the administration of their medication in the period immediately after discharge from acute care facilities.

Medication regimen complexity and adherence among older adults

Two studies were conducted to examine the relationship between medication regimen complexity and adherence among older adults recently discharged from hospitals (N = 178) and those not recently hospitalized (N = 98). Medication regimen complexity was measured by the Medication Complexity Index (Kelley, 1988), which measures the number, frequency, and types of actions required to enact a medication regimen. Adherence to the regimen was measured by pill count and verbal self-report. The negative correlations between regimen complexity and adherence were in the predicted direction but did not achieve statistical significance. Medication regimen complexity may have a larger impact on aspects of medication management other than adherence to the prescriptive regimen.

Multiple drug regimens: medication compliance among veterans 65 years and older

In this study we attempted to develop a profile that could be used prospectively to identify veterans over 64 years of age who might be at risk for medication noncompliance. Male veterans (N = 249) having from one to seven oral daily prescribed medications were studied. Instruments administered to determine their relationship to compliance were the Paired-Associate Test, the Mini Mental State, the Multidimensional Health Locus of Control, and the Standard Depression Scale. Compliance was determined by a pill count made at two home visits. Seventy-three percent of the subjects were noncompliant. Variables significantly related to noncompliance by bi-variate analysis were included in the stepwise logistic regression to develop a predictive model of noncompliance. Ethnicity and number of daily prescribed pills were the only significant variables in the final model. The model correctly classified the subjects as compliant/noncompliant in 77% of the cases. Discussions during home interviews revealed a number of common problems.

Compliance measurement with arthritis regimen

Rheumatoid arthritis affects nearly 6.5 million Americans, causing significant disability and suffering. Improvement of treatment efficacy is of considerable importance. Because adherence moderates treatment effects, efficacy studies need to account for the extent to which the patient complied. This paper reviews the methods of assessing adherence. These methods fall into four categories: (1) clinical measures (therapeutic outcome and clinician judgement); (2) self-report (interviews, questionnaires, and daily records); (3) direct measures (direct observation and biologic assays); and (4) indirect measures (pill counts, pharmacy refills, and electronic monitors). The most commonly used measure is some form of self-report. The clinical measures are problematic as compliance indicators and should not be used in this regard. Selections among the other categories should be made based upon the behavior being studied, the cost and resources available, the capabilities of the patient, the questions being asked, and the level of accuracy and detail desired. There are no perfect measures.