**10. Barriers of adherence to medication**

There are barriers of adherence to medication that affect patients with cardiovascular diseases, diabetes mellitus and hypertension thus, leading to non-adherence. These barriers are classified into different categories of factors affecting adherence of patients to their medication. Categories of factors affecting patients' adherence to medication in Africa include sociodemographic, economic, environmental, condition-related factors, therapy-related, health care team and system-related factors, and patient-related factors [73–79]. Sociodemographic, economic and environmental factors are composed of low-income, poverty, minority race-ethnicity, social support, copayments, and health literacy [73, 77]. Health care team and system-related factors include patient-clinician relationship, communication style, lack of team-based care, clinician burn out, lack of knowledge, lack of policies, lack of ad hoc screening and proper referral systems, and poor universal health insurance coverage [73, 74, 76, 77, 80, 81]. Complex regimen, treatment changes, failure and duration, adverse effects, and refill frequency and consolidation are therapy-related factors [73, 78]. Condition-related factors include multiple chronic conditions, depression, psychoses, drug or alcohol abuse, dementia, major disability, severity of symptoms, and quality of life [73]. Patient-related factors include perception of illness and treatment efficacy, denial of diagnosis, fear of dependence or adverse effects, lack of knowledge, forgetfulness, and low selfefficacy [73, 80, 81].

Several interventions can be put in place to curb factors affecting patients' adherence to medication. Therapy-related and condition-related factors could be minimized by prescribing few medications which can be implemented using once daily single-pill combinations [71]. Use of once daily single-pill combinations is associated with better adherence and hypertension control [71, 82]. Also, clinicians can prescribe a larger number of medications with each prescription to reduce refill frequency [69, 71]. Patients with NCDs frequently have co-morbidities requiring additional medication to their medicines for NCDs thus, refill consolidation so that multiple medications are obtained at the same time can improve adherence [69, 71].

To curb some of the health care team and system-related factors, patients should trust and be confident that the clinician is competent and has their best interest when making management decisions [73]. Patients, especially racial-ethnic minorities, should actively participate in decisions about the management of their NCDs and what medication to take [69, 73]. Policies addressing procurement process of medication and control of NCDs should be developed and implemented in health systems [74]. Also, the use of generic medicines for NCDs and improvement of health insurance coverage will reduce the cost of care for patients with NCDs therefore, solving some of the barriers to adherence [74].

Dispensing models can be implemented to assist with monitoring adherence to medicines and the treatment outcome.

### **11. Dispensing models to assist with adherence and treatment outcome**

Poor adherence to medication is a major contributor to uncontrolled cardiovascular diseases, diabetes mellitus and hypertension. Monitoring and detection of adherence of patients to their medication using different dispensing models assist with assessing the treatment outcome. Medication adherence can be measured directly or indirectly using several measurements either separately or together [83, 84]. Indirect measurements include pill count, patient interviews, prescription refills data, electronic monitoring system, directly observed technique, and questionnaire [83, 84]. Direct measurements include measurement of drug levels and digital medicine [83, 84]. Prescription refills data, pill count, directly observed technique, and electronic monitoring system are objective

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*Exploring Cardiovascular Diseases Treatment in Africa DOI: http://dx.doi.org/10.5772/intechopen.95871*

drug levels and digital medicine [83, 84].

adherence [83].

visits) [83].

prescribed [83].

measurement whereas, questionnaires and patient interviews are subjective measurements [83, 84]. Biomedical measurements consist of measurement of

Dispensing models include interviewing patients, questionnaires, pill count, prescription refills data, electronic monitoring system, measurement of drug levels,

Patient's interview is when a physician questions the patient about adherence to medicines. The physician asks the patient questions related to medicine-taking behavior thus, communication skills of the physician and the ability to conduct nonjudgmental discussion is important [73]. The health care professional asks the patient to estimate their own medication-taking behavior, such as which percentage of dose that they may miss within a designated period or the frequency that they are unable to follow the medication regime [83]. On the other hand, questions asked to the patient by the health care professional can be based on the patient's knowledge on the prescribed regime, including drugs' name, schedule, and indications [83]. Health care professionals then evaluate their response to determine the level of

Questionnaires are forms which can be completed by patients, trained nurses or healthcare professionals as a tool to monitor adherence [73]. Types of questionnaires used to measure adherence are the Brief Medication Questionnaire, Hill-Bone Compliance Scale (Hill-Bone), Eight-Item Morisky Medication Adherence Scale (MMAS-8), Medication Adherence Questionnaire (MAQ ), Self-Efficacy for Appropriate Medication Use Scale (SEAMS), and the Medication Adherence Report Scale (MARS) [85, 86]. A well-known and mainly used questionnaire to measure

Pill count is a frequently used dispensing model to monitor adherence where counting returned pills by a patient gives an overview of what has been taken by the patient [73]. The health care provider counts the number of dosage units that have been taken by the patient between two scheduled appointments or clinic visits [83]. This number would then be compared with the total number of units received by the patient to calculate the adherence ratio [83]. The equation for calculating pill count is as follows: (Number of dosage units dispensed − Number of dosage units remained) / (prescribed number of dosage unit per day × number of days between 2

Prescription refill data requires availability of electronic monitoring of drug prescriptions in pharmacies [73]. Prescription refill data assists with obtaining a rough estimate of medicines adherence and persistence by calculating the percentage of days covered by the prescriptions [73]. When measuring adherence using prescription refills, it is assumed that prescription-refilling patterns correspond to the patient medication-taking behavior and that the medication is taken exactly as

Electronic monitoring system consists of a device in which a microcircuit is incorporated into medication packages and any removal of a dose of the medicine is detected in real time, time stamped, analyzed, stored, and communicated [73, 83]. Commonalities of different electronic monitoring devices include (i) recorded dosing events and stored records of adherence, (ii) audiovisual reminders to signal time for the next dose, (iii) digital displays, (iv) real-time monitoring, and (v) feed-back on adherence performance [83]. The commonly used electronic monitoring device is

the Medication Event Monitoring System (MEMS) [73, 83].

**12. Different dispensing models used to measure adherence**

digital medicine, and directly observed technique [73].

adherence is the Morisky questionnaire [69, 83].

*Lifestyle and Epidemiology - The Double Burden of Poverty and Cardiovascular Diseases...*

non-adherence. These barriers are classified into different categories of factors affecting adherence of patients to their medication. Categories of factors affecting patients' adherence to medication in Africa include sociodemographic, economic, environmental, condition-related factors, therapy-related, health care team and system-related factors, and patient-related factors [73–79]. Sociodemographic, economic and environmental factors are composed of low-income, poverty, minority race-ethnicity, social support, copayments, and health literacy [73, 77]. Health care team and system-related factors include patient-clinician relationship, communication style, lack of team-based care, clinician burn out, lack of knowledge, lack of policies, lack of ad hoc screening and proper referral systems, and poor universal health insurance coverage [73, 74, 76, 77, 80, 81]. Complex regimen, treatment changes, failure and duration, adverse effects, and refill frequency and consolidation are therapy-related factors [73, 78]. Condition-related factors include multiple chronic conditions, depression, psychoses, drug or alcohol abuse, dementia, major disability, severity of symptoms, and quality of life [73]. Patient-related factors include perception of illness and treatment efficacy, denial of diagnosis, fear of dependence or adverse effects, lack of knowledge, forgetfulness, and low self-

Several interventions can be put in place to curb factors affecting patients' adherence to medication. Therapy-related and condition-related factors could be minimized by prescribing few medications which can be implemented using once daily single-pill combinations [71]. Use of once daily single-pill combinations is associated with better adherence and hypertension control [71, 82]. Also, clinicians can prescribe a larger number of medications with each prescription to reduce refill frequency [69, 71]. Patients with NCDs frequently have co-morbidities requiring additional medication to their medicines for NCDs thus, refill consolidation so that multiple medications are obtained at the same time can improve

To curb some of the health care team and system-related factors, patients should

Dispensing models can be implemented to assist with monitoring adherence to

**11. Dispensing models to assist with adherence and treatment outcome**

Poor adherence to medication is a major contributor to uncontrolled cardiovascular diseases, diabetes mellitus and hypertension. Monitoring and detection of adherence of patients to their medication using different dispensing models assist with assessing the treatment outcome. Medication adherence can be measured directly or indirectly using several measurements either separately or together [83, 84]. Indirect measurements include pill count, patient interviews, prescription refills data, electronic monitoring system, directly observed technique, and questionnaire [83, 84]. Direct measurements include measurement of drug levels and digital medicine [83, 84]. Prescription refills data, pill count, directly observed technique, and electronic monitoring system are objective

trust and be confident that the clinician is competent and has their best interest when making management decisions [73]. Patients, especially racial-ethnic minorities, should actively participate in decisions about the management of their NCDs and what medication to take [69, 73]. Policies addressing procurement process of medication and control of NCDs should be developed and implemented in health systems [74]. Also, the use of generic medicines for NCDs and improvement of health insurance coverage will reduce the cost of care for patients with NCDs

therefore, solving some of the barriers to adherence [74].

medicines and the treatment outcome.

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efficacy [73, 80, 81].

adherence [69, 71].

measurement whereas, questionnaires and patient interviews are subjective measurements [83, 84]. Biomedical measurements consist of measurement of drug levels and digital medicine [83, 84].
