STRATEGIES TO IMPROVE MEDICATION ADHERENCE IN ADULT
PATIENTS WITH HYPERTENSION IN PRIMARY CARE
by
Manreet Cheema
B.Sc.N., Manipal Academy of Higher Education, 2011

PROJECT SUBMITTED IN PARTIAL FULFILLMENT OF
REQUIREMENT FOR THE DEGREE OF MASTERS OF SCIENCE
IN
NURSING: FAMILY NURSE PRACTITIONER

UNIVERSITY OF NORTHERN BRITISH COLUMBIA
April 2025
© Manreet Cheema, 2025

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Abstract
Background: Hypertension affects 1.28 billion individuals globally and is one of the key
public health issues in Canada impacting nearly one in four adults. Non-adherence to
antihypertensive medications is a major contributor to uncontrolled hypertension and
related complications.
Objective: To examine the strategies that can be used by primary care providers to
improve medication adherence in adult patients with hypertension.
Methods: An integrative literature review approach (Toronto & Remington, 2020) was
used along with the PRISMA guidelines (2021). A systematic search of CINAHL and
Ovid MEDLINE was undertaken. A critical appraisal was conducted using two tools.
Results: Six studies met the inclusion criteria. Study designs included randomized
controlled trials, observational cohorts, and mixed-methods studies from developed
countries. Three key strategies were identified to improve medication adherence in adults
with hypertension within primary care settings: patient-centered interventions (e.g.,
education tools, reminders, self-monitoring); collaborative care strategies involving
pharmacists and nurses; and fixed-dose combination therapies.
Conclusion: Findings indicate that while several single strategies can support medication
adherence in adults with hypertension, primary care providers should use a combination of
strategies to achieve the most effective improvements in medication adherence and clinical
outcomes.

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Table of Contents

Abstract ................................................................................................................................. ii
Table of Contents ................................................................................................................. iii
List of Tables ......................................................................................................................... v
List of Figures ...................................................................................................................... vi
Glossary of Terms ............................................................................................................... vii
Introduction ......................................................................................................................... 8
Background .......................................................................................................................... 9
Overview of Hypertension................................................................................................. 9
Uncontrolled Hypertension ............................................................................................ 9
Definition and Diagnosis ............................................................................................... 9
Management ................................................................................................................. 10
Medication Adherence ..................................................................................................... 10
Definition ..................................................................................................................... 10
Causes of Medication Non-Adherence......................................................................... 11
Consequences of Medication Non-Adherence ............................................................. 12
Hypertension Management in the Context of Primary Care ........................................... 12
Definitions of Primary Care and Primary Care Providers ......................................... 12
Role of Primary Care Providers in Hypertension Management.................................. 13
Methods .............................................................................................................................. 14
Research Question and Objective .................................................................................... 14
Literature Sources: Search Strategy and Databases ........................................................ 14
Literature Selection.......................................................................................................... 15
Inclusion Criteria ......................................................................................................... 15
Exclusion Criteria ........................................................................................................ 15
Charting the Data and Critical Appraisal ........................................................................ 16
Ethics ............................................................................................................................... 16
Findings .............................................................................................................................. 16
Patient-centered Interventions ......................................................................................... 18
Collaborative Care Strategies .......................................................................................... 21
Fixed Dose Combination Therapies ................................................................................ 22

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Discussion ........................................................................................................................... 23
Collaborative Care Strategies .......................................................................................... 25
Fixed Dose Combination Therapies ................................................................................ 26
Implications for Nurse Practitioner Practice ................................................................... 27
Limitations ....................................................................................................................... 27
Conclusion .......................................................................................................................... 28
References ........................................................................................................................... 30
Appendices .......................................................................................................................... 41
Appendix A: Database Rationale and Systematic Search Strategy ................................. 41
Appendix B: Literature Matrix ........................................................................................ 46

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List of Tables
Table 1: Data Extraction Table ........................................................................................... 46
Table 2: Critical Appraisal Table ....................................................................................... 52

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List of Figures
Figure 1: PRISMA Flow Diagram ....................................................................................... 17
Figure 2: Features of Research Studies............................................................................... 18
Figure 3: CINAHL Search Strategy ..................................................................................... 43
Figure 4: Ovid MEDLINE Search Strategy ......................................................................... 45

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Glossary of Terms
Collaborative Care: A care strategy involving inter-professional collaboration, such as
within nurse practitioners, physicians, pharmacists and nurses.
Hypertension: Defined as elevated blood pressure, with an average systolic blood
pressure (SBP) above 135 mm Hg or diastolic blood pressure (DBP) above 85 mm Hg
measured using Automated Office Blood Pressure.
Fixed-Dose Combination (FDC): Medications that include a combination of two or more
antihypertensive agents into a single pill.
Medication Adherence: The patient’s voluntary cooperation in taking medication as
prescribed, including adherence to the timing, dose, and frequency of administration.
Nurse Practitioners (NPs): Health care professionals with graduate level of nursing
education and advanced nursing practice competencies. NPs provide evidence-based
healthcare, including diagnosing conditions, ordering diagnostic services, and prescribing
and dispensing medications.
Patient-centered Interventions: Strategies that involve shared decision-making with
patient and provide support responding to patient feedback about medication use, treatment
goals, and medication-taking behavior.
Primary Care: A comprehensive approach to healthcare across all ages and stages of life,
including prevention, health promotion, treatment, rehabilitation, and palliation.
Primary Care Providers (PCPs): Refers to family physicians or nurse practitioners in
British Columbia (BC). PCPs deliver longitudinal care, routinely assess blood pressure,
initiate pharmacological treatments, and coordinate referrals when necessary.

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Strategies to Improve Medication Adherence in Adult Patients with Hypertension in
Primary Care
Introduction and Background
Globally, hypertension is recognized as an epidemic that affects 1.28 billion people
(World Health Organization, 2021). Hypertension is also a significant public health
concern in Canada impacting nearly one in four adults (Bushnik et al., 2023). In British
Columbia (BC), the age-standardized prevalence rate for hypertension was 22.5 per 100
people, and the age-standardized annual incidence rate was 20.2 per 1000 people over the
age of 20 (Government of BC, 2024).
Hypertension is a significant risk factor for other conditions (e.g., cardiovascular
disease, stroke, renal disease) and premature mortality (Bushnik et al., 2023; Choudhry et
al., 2022). Hypertension contributes to nearly 50% of deaths related to cardiovascular
disease and stroke, which are two leading causes of mortality in Canada (Bushnik et al.,
2023). An urgent need for effective hypertension management remains to mitigate these
consequences (Waked et al., 2019).
Effective hypertension management includes several essential components like
lifestyle modifications (e.g., adopting the DASH diet, engaging in regular physical activity,
managing weight, moderating alcohol consumption, stress reduction, and smoking
cessation) and pharmacological treatment and medication adherence (Rabi et al; 2020).
Medication adherence is one component of management in achieving optimal outcomes
(Burnier & Egan, 2019). A high level of adherence to antihypertensive medications is
difficult for various reasons (Zhou et al., 2024). Consequently, non-adherence to these
medications is the primary cause of poor blood pressure (BP) control, leading to increased
risk of complications including stroke, myocardial infarction, heart failure, chronic kidney

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disease, and hypertensive retinopathy (Lee et al., 2022). I witness the devastating results
caused by medication non-adherence among people with hypertension in my acute care
nursing practice.
Hypertension is one common reason for people to visit primary care providers
(PCP) like family physicians and nurse practitioners (NP) yet, unlike many conditions,
hypertension is predominantly managed within these primary care settings rather than
referral to specialists (Waked et al., 2019). Medication non-adherence in the context of
hypertension contributes to poor clinical outcomes (Hamrahian, 2020), making it a
significant concern for NP practice. The aim of this integrative literature review is to
examine the strategies that can be used by PCPs to improve medication adherence in adult
patients with hypertension.
Background
Overview of Hypertension
Uncontrolled Hypertension
Hypertension Canada (2024) reports that BP control rates in Canada remain
suboptimal, with only two-thirds of Canadians having their BP controlled, and a renewed
effort is required to optimize this control. A suboptimal control rate has profound health
implications; uncontrolled hypertension affects nearly all organs in the body by causing
damage at microvascular and macro vascular levels (Nadar & Lip, 2021).
Definition and Diagnosis
The Hypertension Canada Guidelines (Rabi et al., 2020) define hypertension as
elevated BP measured using Automated Office Blood Pressure (AOBP), with an average
systolic blood pressure (SBP) above 135 mm Hg or diastolic blood pressure (DBP) above

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85 mm Hg, assessed using the most accurate technique. For patients with diabetes, the
diagnostic threshold is lower, with hypertension confirmed if SBP is >130 mm Hg or DBP
is >80 mm Hg (Rabi et al., 2020). For all patients, hypertension is diagnosed during the
initial visit if AOBP SBP is >180 mm Hg or DBP is >110 mm Hg (Rabi et al., 2020).
Moderate elevations during the initial visit, such as AOBP SBP 135-179 mm Hg or DBP
85-109 mm Hg, require out-of-office confirmation, including 24-hour ambulatory or home
BP monitoring, to verify elevated readings and rule out white coat hypertension (Rabi et
al., 2020).
Management
The Hypertension Canada Guidelines (Rabi et al., 2020) report that comprehensive
management of hypertension includes lifestyle modifications such as regular moderateintensity exercise, weight loss, DASH diet, reduced sodium intake, and limited alcohol
consumption (Rabi et al., 2020). Pharmacological therapy is central for adults with average
DBP >100 mm Hg or SBP > 160 mm Hg and strongly advised for those with DBP >90
mm Hg or SBP > 140 mm Hg with cardiovascular risks or target organ damage (Rabi et
al., 2020). However, management recommendations vary internationally regarding optimal
BP thresholds (Filippone et al., 2022).
Medication Adherence
Definition
Medication compliance is defined as the extent to which the patient’s behavior
matches the prescriber’s recommendations (Mir, 2023). The term was later replaced with
adherence, as compliance implies conformity to treatment recommendations, placing the
blame for noncompliance solely on the patient and suggesting they are uncooperative or

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untrustworthy (Ghosh et al., 2017). In contrast, medication adherence refers to the
patient’s voluntary cooperation in taking medication as prescribed, including adherence to
the timing, dose, and frequency of administration (Zhou et al., 2024).
Patient adherence to medication is divided into three major phases: (1) initiation
(starting the prescribed treatment), (2) implementation (consistently following the
prescribed dosing regimen), and (3) persistence (continuing the treatment over the
prescribed duration) (Choudhry et al., 2022). Failure at these phases constitutes nonadherence (Choudhry et al., 2022). Furthermore, medication adherence is a shared
agreement between patients and clinicians (Chang et al., 2021). Adherence to long-term
corrective medication in patients with hypertension is a crucial measure for reducing health
consequences (Zhou et al., 2022)
Causes of Medication Non-Adherence
Causes of medication non-adherence are complex and multifaceted, influenced by
unintentional and intentional factors (Jayasree et al., 2024). Unintentional non-adherence
occurs when patients are committed to taking their medications but face barriers that are
beyond their control (Jayasree et al., 2024). Unintentional barriers include individual
capacity related to dexterity, memory, difficulty understanding instructions, difficulty
managing complex regimens, or high costs (Lee et al., 2018; Singer et al., 2022). Provider
and system-related barriers include communication gaps, healthcare access, and
prescription issues (Lee et al., 2018).
In contrast, intentional non-adherence occurs when patients decide not to follow the
prescribed treatment due to personal beliefs and experiences (Jayasree et al., 2024).
Personal beliefs and experiences may include questioning the necessity of the medication,

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feeling asymptomatic, and fearing side effects or concerns about dependency and
depression (American Medical Association, 2023; Kleinsinger, 2018). These personal
beliefs and experiences about illness and treatment are important, so what may seem
puzzling from the provider's perspective is a rational response within the context of the
patient’s life (While, 2020).
Consequences of Medication Non-Adherence
Vrijens et al. (2017) reported that adherence issues are common in patients with
hypertension, resulting in increased health risks (e.g., coronary and cerebrovascular
events). Medication non-adherence is the primary cause of poor BP control, leading to
increased risk of complications like stroke, myocardial infarction, heart failure, chronic
kidney disease, and hypertensive retinopathy (Lee et al., 2022). Singer et al. (2022) argued
that such adherence challenges are especially prevalent within primary care settings.
Ultimately, medication non-adherence results in substantial health consequences,
underscoring the need for targeted interventions in primary care (Vrijens et al., 2017).
Hypertension Management in the Context of Primary Care
Definitions of Primary Care and Primary Care Providers
Primary care is a comprehensive approach to healthcare across all ages and stages
of life including prevention, health promotion, treatment, rehabilitation, and palliation
(World Health Organization, 2022). Thousands of Canadians receive daily primary care
services from NPs, family physicians, and other providers (e.g., nurses, dietitians,
physiotherapists, and social workers) (Canadian Institute for Health Information, 2024). In
BC, PCP refers to family physicians or NPs (Government of BC, 2024). The distinction is
based on their responsibility for delivering longitudinal care, which involves the ongoing,

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comprehensive management of a patient's health over time (Government of BC, 2025a).
Other healthcare professionals listed above play critical roles in primary care teams but are
not formally designated as PCPs within the provincial healthcare framework as their
contributions often focus on specific aspects of patient care and are typically task-specific
(Government of BC, 2025a).
Role of Primary Care Providers in Hypertension Management
Primary care providers manage hypertension by routinely assessing patients’ BP,
identifying risk factors, and implementing guideline-based protocols such as those
recommended by Hypertension Canada and BC provincial guidelines (Government of
British Columbia, 2024). Specifically, PCPs diagnose hypertension, initiate
pharmacological treatments, and provide individualized counselling on lifestyle
modifications (e.g., dietary changes, exercise, sodium reduction) to help patients achieve
BP targets (Government of British Columbia, 2024; Rabi et al., 2020). Primary care
providers also coordinate referrals to specialized care when complications or complex
cases arise (Teh et al., 2020). Their longitudinal care helps provide continuous
management along with fostering trust and improving communication, which strengthens
the overall approach to hypertension management (Strumann et al., 2024).
However, PCPs face multiple challenges in hypertension management. Davis et al.
(2024) reported that achieving recommended BP targets is complicated by the complexity
of medication regimens, variability in patient adherence, and individual patient differences
(e.g., medical comorbidities like metabolic syndrome). Parati et al. (2021) further
emphasized that BP control may be suboptimal when its assessment is only based on
AOBP values, and there is limited access to home monitoring; this hinders the ability to

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obtain more accurate readings, which are critical for guiding treatment decisions. Primary
care providers still remain well suited to potentially optimize hypertension management
including medication adherence.
Methods
The approach for conducting and reporting this integrative review was informed by
Toronto and Remington (2020) and PRISMA guidelines (2021). Critical appraisal was
undertaken using two tools: (Mixed Methods Appraisal Tool [MMAT], 2018) and (Critical
Appraisal Skills Programme [CASP], 2024).
Research Question and Objective
Research question: For adult patients with hypertension, what strategies can be used by
primary care providers to improve patient medication adherence?
Research objective: To examine the strategies that can be used by PCPs to improve
medication adherence in adult patients with hypertension.
Literature Sources: Search Strategy and Databases
The search strategy was developed using four key concepts to identify relevant
literature (Appendix A): hypertension, adult population, medication adherence, and
primary care. The final search strategy combined these four concepts using the Boolean
operator AND: (“Hypertension” OR “high blood pressure” OR “essential hypertension”)
AND (“adult patient” OR “middle-aged” OR “elderly” OR “18 years and older”) AND
(“medication adherence” OR “medication compliance”) AND (“primary care” OR “family
practice” OR “primary care physician” OR “Primary care Nurse Practitioners”.
Two databases were selected to search for this literature: CINAHL and Ovid
MEDLINE. The search strategy was then executed in these two databases on October 29,

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2024. Time limits were applied (January 1, 2016, through October 29, 2024) to ensure that
the search captured the most current developments.
Literature Selection
Inclusion and exclusion criteria were developed to screen literature found in the
two databases.
Inclusion Criteria
•

Studies involving adult patients (>18 years) with essential or primary hypertension.

•

Research conducted in primary care.

•

Studies providing strategies to improve medication adherence or compliance.

•

Studies published between January 1, 2016, and October 29, 2024.

•

English-language publications, and

•

Studies from developed countries.

Exclusion Criteria
•

Studies involving pediatric populations.

•

Research was conducted exclusively in non-primary care settings (e.g., hospitals).

•

Studies that did not address medication adherence as a primary or secondary
outcome.

•

Studies published outside the defined date range.

•

Non-English language publications.

•

Studies from developing or underdeveloped countries.
Next, these inclusion and exclusion criteria were applied during the two-stage

screening process to identify literature relevant to the research question and objective.
There were no restrictions on study design, quality, and sex or gender differences. In the

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first stage, titles and abstracts were screened against the inclusion and exclusion criteria for
relevance, and duplicates were removed. Any title/abstract that was deemed relevant was
advanced to the second stage. During the second stage, full text documents selected from
stage one were reviewed using the inclusion and exclusion criteria.
Charting the Data and Critical Appraisal
Data were charted using an extraction table (Appendix B [Table 1]). The
development and completion of this table facilitated critical appraisal of this literature
which was charted in a table (Appendix B [Table 2]). The studies were rated on a scale of
low, moderate, and high-quality evidence. Two tools were used to undertake this appraisal
MMAT (2018) and CASP (2024).
Ethics
Ethics approval was not needed to conduct this integrative review because it is
based on existing literature in the public domain.
Findings
A total of six research studies met the final inclusion criteria and were included in
this review (Figures 1-2, Appendix B [Table 1], Appendix B [Table 2]). Of the six
documents, three originated from the United States, while others were from the United
Kingdom, Australia, and Italy. All these countries are developed, high-income nations. The
earliest publication identified is by Levi et al. (2016) and the most recent is by Sarkar et al.
(2024). All studies were peer-reviewed.
Five authors used quantitative methods whereas, one study was mixed-methods.
Authors of these studies utilized various designs (e.g. randomized controlled trials (Chow
et al., 2017; Kassavou et al., 2021; Sarkar et al., 2024), cohort [observational (Coe et al.,

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2020), retrospective observational (Levi et al., 2016)], and mixed-methods (Yamane et al.,
2020). Participants in the studies had hypertension including other medical comorbidities
(e.g., diabetes, high cholesterol). There were a greater number of females/ women versus
male/men participants in four of the studies. One study had more male participants than
female, and another reported an approximately equal distribution between genders. None
of the studies in this review specifically focused on NPs as primary care PCPs. None of the
authors specifically reported on the inclusion of people with non-binary or diverse gender
identities. Most participants were Caucasian.

Figure 1
PRISMA Flow Diagram

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Figure 2
Features of Research Studies

The studies were critically appraised using the CASP (2024) and MMAT (2018)
checklists. Critical analysis details like study strengths and limitations are presented in
Appendix B (Table 2). Overall, the study recommendations offered various strategies that
can enhance medication adherence in adult patients with hypertension. These strategies
include patient-centered interventions, collaborative care strategies, and fixed dose
combination (FDC) therapies.
Patient-centered Interventions
Tailored, patient-centered interventions emerged as effective strategies in three
studies (Kassavou et al., 2021; Sarkar et al., 2024; Yamane et al., 2020). All three studies
demonstrated that patient-centered strategies, such as educational tools, reminders, and
self-monitoring, can improve medication adherence.

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Yamane et al. (2020) explored the effectiveness of provider education combined
with a personalized decision aid (PDA) in a mixed-methods study involving 24 nonadherent hypertensive patients. The paper-based PDA consolidated vital signs, laboratory
results, lifestyle factors, and an atherosclerotic cardiovascular disease risk score into one
document. By having all this information in one document, providers could quickly access
data that would otherwise be spread across different areas of a paper chart. The patients
could also easily visualize their progress on one document. The PDA also served as a
prompt to discuss lifestyle modifications, smoking cessation, medication adherence, and
regular follow-up visits. After three months, prescription refill rates were used to measure
study outcomes and were found to increase from 79% to 96%. However, the small sample
size and lack of a control group may limit the intervention’s generalizability to the larger
population.
Similarly, Kassavou et al. (2021) studied another tailored, patient-centered strategy
using a randomized controlled trial (RCT) with 101 non-adherent, hypertensive patients. A
nurse conducted a brief counselling session about medication adherence followed by an
84-day text messaging program customized using patient-reported information and practice
records to address intentional and unintentional non-adherence. For intentional nonadherence, messages reinforced positive beliefs about taking antihypertensive medication
(e.g., "Even if you do not feel different after taking your pills, you are keeping your blood
pressure under control by taking them regularly" p.3), and negative beliefs were countered
in a non-confrontational manner (e.g., "Your tablets support you in maintaining blood
pressure control" p.3). For unintentional non-adherence, reminders were sent at scheduled
times (e.g., "Do not forget to take your medication today: Ramipril, 2 tablets, 1.25 mg, at

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16:00" p.3). Biochemically validated medication adherence was measured through urine
samples after three months, and this showed a 20% improvement in the intervention group
compared to the control group. A practice nurse who was blinded to group allocation
recorded decreases of 9.16 mmHg systolic and 4.85 mmHg diastolic in the intervention
group. Self-reported medication adherence was also assessed at baseline and followed up
using a weekly adherence question ("How many days in the past week have you taken all
your prescribed tablets?" p. 3). By the end of the trial, self-reported adherence improved by
an average of one additional day per week in the intervention group compared to the
control group (Kassavou et al., 2021).
Likewise, Sarkar et al. (2024) investigated a tailored, patient-centered approach
through a RCT involving 200 low-income patients, each completing four primary care
visits over six months. The intervention group received free home BP monitors, enabling
them to measure and report four weekly readings at follow-up visits. Outcomes were
measured by reductions in BP and scores on the 14-item Therapy Adherence Scale (TAS),
developed by Kim et al. (2000), which covered three domains: sodium reduction,
appointment keeping, and medication taking. Items were rated on a 4-point scale, with
total scores ranging from 14 to 56. By the end of the study, the intervention group showed
greater BP control (82% vs. 54%) and improved TAS scores, increasing from a mean of
38.7 to 42.6. The authors reported that among the three domains assessed by the TAS,
medication adherence showed the greatest improvement in the intervention group and
proposed that regular BP monitoring helps patients to remember and consistently take their
antihypertensive medications.

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Collaborative Care Strategies
In two studies (Coe et al., 2020; Kassavou et al., 2021), the collaborative care
strategy was shown to improve medication adherence. In the RCT by Kassavou et al.
(2021), the collaborative component involved nurses delivering brief counselling sessions.
These sessions included advice on the importance of taking BP medication and help with
signing up for digital support (either text messages or a phone app). This session was then
followed by an 84-day text messaging program, which was found to improve
biochemically validated medication adherence compared to the control group, and the
results were statistically significant.
Coe et al. (2020), in their observational cohort study, examined the Michigan
Pharmacists Transforming Care and Quality (MPTCQ) program (Choe et al., 2018),
integrating primary care pharmacists into physician organizations (POs) to care for adults
with chronic conditions, including hypertension. The MPTCQ program included two
pharmacist cohorts across 17 participating POs. A total of 27 pharmacists took part, 17 in
Cohort 1 and 10 in Cohort 2, and data was collected from pharmacist encounters over 27
months.
For hypertension management, pharmacists provided disease state management
visits for 2,224 hypertensive patients in Cohort 1 (average of 1.9 visits per patient, 66% by
phone) and 1,715 patients in Cohort 2 (average of 2.3 visits per patient, 57% by phone).
The disease state management visits included medication therapy optimization,
prescription adjustments, patient education, laboratory monitoring, motivational
interviewing, and counselling on lifestyle modifications (Coe et al., 2020). Pharmacists
identified medication adherence issues in 27% of Cohort 1 encounters and 21% in Cohort

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2 and intervened with counselling, adherence aids, and medication adjustments. Blood
pressure was measured at baseline and during follow-up visits (Coe et al., 2020). Authors
reported that pharmacist interventions significantly reduced BP, with severe cases
dropping to 30 mmHg (Coe et al., 2020). All surveyed patients agreed that pharmacists
explained things clearly and helped them best use their medications (Coe et al., 2020).
Fixed Dose Combination Therapies
Two studies identified FDC therapies as effective for improving medication
adherence, primarily by simplifying regimens and reducing pill burden (Levi et al., 2016;
Chow et al., 2017). In a nationwide, population-based retrospective observational study
conducted in Italy, Levi et al. (2016) analyzed over 1.2 million patient records of patients
using a national medical database to compare adherence between patients prescribed a
FDC (olmesartan/amlodipine in a single pill) versus the same components given as
separate pills. Adult hypertensive patients with at least two years of medical history in the
health database and a minimum of six months of follow-up were included in the study. The
study used prescription records from general practitioners to measure adherence using the
Proportion of Days Covered (PDC) method, which calculates how many days a patient had
medication available during the follow-up period. Patients were grouped as having high
(PDC ≥ 80%), intermediate (PDC = 40%–79%), or low (PDC < 40%) adherence. The
results showed that 55.1% of patients who took the single-pill combination had high
adherence, as compared to only 15.9% of those taking two separate pills. Even after
adjusting for patient differences, those on the FDC pill were over six times more likely to
be highly adherent. Given the large sample size and the use of valid, objective adherence
measures, the study provided strong evidence that simplifying antihypertensive treatment

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into a single-pill regimen can improve medication adherence and enhance health outcomes
in adult patients with hypertension.
Similarly, Chow et al. (2017) studied combination therapy in a randomized,
placebo-controlled, double-blind, crossover trial testing a “quad pill.” The “quad pill”
combined four common antihypertensive agents: irbesartan (37.5 mg), amlodipine (1.25
mg), hydrochlorothiazide (6.25 mg), and atenolol (12.5 mg), all at quarter doses in a single
daily capsule. Although the sample size was small (21 participants) and the trial duration
was short (4 weeks per treatment phase), 100% of participants achieved target office BP
(<140/90 mm Hg) while on the “quad pill”, as compared to just 33% on placebo.
Participants also rated the “quad pill” as easy or straightforward to take, and all expressed
willingness to continue using it, suggesting high acceptability.
Discussion
Six studies examined in this integrative review directly address the research
question: For adult patients with hypertension, what strategies can be used by primary
care providers to improve patient medication adherence? The studies highlight three
strategies: (1) patient‑centered strategies, including educational tools, reminder systems,
and self-monitoring; (2) collaborative care strategies that involve nurses or pharmacists in
ongoing management; and (3) FDC therapies that reduce pill burden. Each strategy in the
studies showed measurable improvements and enhanced adherence, yet, the broader
literature suggests that the most long-lasting improvements in adherence occur when these
strategies are combined and tailored to individual patient needs. The subsequent passages
in this findings section evaluates how each of these strategies aligns with and differs from
findings in the broader literature.

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Patient-Centered Interventions
Regarding the strategy of patient-centered interventions, authors of three studies in
this review found that educational tools, reminders (e.g., via text messaging), and selfmonitoring of BP can improve medication adherence (Kassavou et al., 2021; Sarkar et al.,
2024; Yamane et al., 2020). Likewise, authors of two RCTs in broader evidence reported
that educational tools in patient-centered interventions like personalized decision aids
improved medication adherence (Wehkamp et al., 2021) and patients engaging in home BP
monitoring displayed a lower incidence of non-adherence than controls (Zhang et al.,
2021). The results of these studies align with previous research conducted by Thakkar et
al. (2016), which found that patient-centered interventions such as text messaging nearly
doubled adherence rates, especially when messages were personalized and interactive, and
by Sarabi et al. (2016), which found that daily or weekly reminders significantly enhanced
adherence.
Additional evidence available in literature outside this review suggests that the
effectiveness of patient-centered interventions may be context-dependent and limited when
implemented in isolation. For example, authors of a pragmatic RCT found that the impact
of text message reminders diminished over 12 months (Ho et al., 2024). Gualtieri and
Rosenbluth (2024) further suggested that this diminished impact on long-term adherence
may be due to notification or alert fatigue that can occur because of the high volume of
smartphone alerts. Additionally, a large RCT by Li et al. (2024) found that home BP
monitoring was not associated with improved control instead, it was linked to poorer
adherence among patients who held incorrect beliefs about antihypertensive treatment.

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There is also a need for more research on patient-centered interventions, such as for those
with limited health literacy (Richter et al., 2024; Stacey et al., 2025).
Collaborative Care Strategies
Regarding the strategy of collaborative care, authors of two studies in this review
demonstrated that pharmacist and nurse-led interventions can improve medication
adherence by recognizing related issues and implementing targeted supports like
counselling and medication adjustments (Coe et al.,2020; Kassavou et al., 2021). Similarly,
broader evidence, such as Santschi et al. (2021) found that a team-based model including
pharmacists, nurses, and physicians improved medication adherence and reduced systolic
BP after 12 months by 7 mmHg. Likewise, Kwakye et al. (2025) undertook a scoping
review to find that 85% of the included studies reported improved medication adherence,
with pharmacists involved in collaborative care models in most of those studies delivering
the interventions.
However, some contrary studies do exist. For example, Bandiera et al. (2025)
undertook a systematic review that assessed the impact of inter-professional collaboration
between pharmacists and community health workers on medication adherence; they found
limited evidence of effect on medication adherence. It is important to note that most of the
methods used by studies in the Bandiera et al. (2025) review to evaluate medication
adherence were subjective, relying on patient self-report. High-quality studies are needed
better to assess the impact of such collaboration on medication adherence (Bandiera et al.,
2025).

26

Fixed Dose Combination Therapies
Regarding the strategy of FDC therapies, authors of two studies in this review
concluded that the use of medication combination helped simplify treatment regimens
resulting in better medication adherence (Chow et al., 2017; Levi et al., 2016). A
substantial amount of evidence in broader literature also supports FDC therapies. A large
meta-analysis by Wei et al. (2023) including 61 studies found that patients on FDC
therapies were 1.29 times more likely to adhere to treatment than those on free-equivalent
combinations, underscoring the benefit of lowering pill burden. An et al. (2020) found in
their systematic, narrative review that the use of FDC therapies reduce clinical inertia and
are generally safe. The American Heart Association Clinical Guidelines (2018) by Whelton
et al. also recommend initiating antihypertensive therapy with FDC therapies due to their
association with improved adherence and treatment outcomes (Derington et al., 2023).
In contrast, DiPette et al. (2018) reported that limited use of FDC therapies remains
due to cost and other barriers like the small number of preferred combinations listed on
formularies, limited availability of combinations, difficulties adjusting doses, and the lack
of scored tablets for dose flexibility. In BC, Pharma Care (BC’s provincial drug coverage
program) does not automatically cover all combinations (Government of British Columbia,
2025b). Newer or less commonly prescribed medications require Special
Authority Approval before they are eligible for coverage (Government of British
Columbia, 2025b).
Overall, the results highlight that the effectiveness of these strategies can vary
depending on patient context and implementation. For example, single-strategy approaches
can fail to produce meaningful or lasting improvements in medication adherence (Pinho et

27

al., 2021) whereas, a combination of these strategies has shown to significantly improve
adherence (Maniki et al., 2024). A broad range of strategies could help address diverse
barriers to medication adherence (Pinho et al., 2021). Hypertension Canada (2025) also
recommends a coordinated, multi-pronged approach individualized to patient needs when
optimizing adherence to antihypertensive therapy.
Implications for Nurse Practitioner Practice
Although none of the studies in this review specifically focused on NPs as primary
care PCPs, the findings support a multi-pronged approach to improving medication
adherence, which aligns with the BCCNM (2024) Entry-Level Competencies for Nurse
Practitioners. As clinicians, NPs can implement evidence-based strategies like patientcentered tools, FDC strategies, and engage in collaborative care (Competencies 1.6b; 1.6d;
1.9a). In the leadership role, NPs can support the prioritization of medication adherence
strategies into health system planning through policy development and resource
stewardship (Competencies 2.1g; 2.3a). As advocates, NPs can address system-level
barriers to adherence and promote equitable access to relevant strategies based on diverse
patient populations (Competencies 3.4a; 3.5b). In the educator role, NPs may promote
health literacy initiatives that help patients with medication adherence (Competencies 4.1b;
4.2a). Lastly, as scholars, NPs can contribute to research by developing and evaluating the
effectiveness of NP-led medication adherence strategies with the goals of informing future
policy and clinical practice (Competencies 5.1a; 5.2e).
Limitations
This integrative review has some limitations. Two tools CASP (2024) and MMAT
(2018) were used to critically appraise the six studies, it is possible that other reviewers

28

may interpret the quality of these studies differently. A comprehensive, systematic search
strategy was used to summarize and synthesize six studies; however, not all relevant
literature may be identified due to the small scope of this student project. For example, the
search was limited between 2016 and 2024. As a result, there is potential for missed
evidence such as earlier high-quality studies which may have contributed to a better
understanding of adherence strategies. In addition, studies from underdeveloped or
developing countries were not included. This exclusion limits the generalizability of the
findings, as strategies effective in high-income countries may not translate to settings with
different healthcare infrastructures.
Conclusion
Hypertension is a leading global health concern, associated with increased risks of
cardiovascular disease, stroke, and renal disease (Lee et al., 2022). In Canada, there is
suboptimal BP control among adults with hypertension (Hypertension Canada, 2024).
Medication non-adherence is the primary cause of poor BP control (Lee et al., 2022).
Hypertension is primarily managed in primary care settings in Canada by PCPs (Waked et
al., 2019). Therefore, an integrative review was conducted to identify targeted strategies
that PCPs can use to enhance medication adherence in adult patients with hypertension.
Systematic searches of CINAHL and Ovid MEDLINE, guided by PRISMA and Toronto
and Remington’s (2020) framework were conducted, six peer-reviewed studies from
developed countries were identified and critically appraised using CASP (2024) and
MMAT (2018).
This integrative review identified three key strategies for improving medication
adherence in adult patients with hypertension: patient-centered interventions (such as

29

education tools, reminders, and self-monitoring), collaborative care strategies (involving
multidisciplinary teams), and FDC therapies. While each strategy demonstrated
effectiveness, comparing the strategies with the literature outside this review showed that
single-strategy approaches may have a limited long-term impact. The results of this review,
when interpreted within the broader evidence, support a multi-pronged, individualized
approach to address intentional and unintentional medication non-adherence in adult
patients with hypertension in primary care.

30

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Appendices
Appendix A: Database Rationale and Systematic Search Strategy
CINAHL was chosen because of its extensive coverage of nursing and allied health
literature (Dhippayom et al., 2023). CINAHL is also an essential database for reviews of
qualitative studies of health service intervention (Dhippayom et al., 2023). This database
has been found to provide many unique studies related to health service intervention that
may not be indexed in other primary databases (Dhippayom et al., 2023). Ovid MEDLINE
was included to capture a broader range of biomedical and clinical literature addressing
hypertension and its management (Wolters Kluwer, n.d.).
For the concept of hypertension, both controlled vocabulary and free-text keywords
were used to identify studies. For example, in Ovid MEDLINE, the exploded Mesh
Heading (MH) “Hypertension” was combined with free-text terms such as “high blood
pressure,” “essential hypertension,” and “arterial hypertension”. In CINAHL, similar
strategies were used with subject headings (e.g., SH “Hypertension+”) and keywords.
Combining these terms with the Boolean operator OR ensured that studies using varying
terms for hypertension were captured.
Mesh Headings such as MH “Adult+” and free-text terms such as “adult patient,”
“middle-aged,” “elderly,” “older adults,” and “18 years and older” were used to ensure that
studies focused on adult patients. In both databases, these terms were combined with
Boolean operator OR to maximize sensitivity to the adult population.
Medication adherence was identified using a controlled vocabulary (e.g., MH
“Medication Compliance” in CINAHL and the corresponding MH in Ovid MEDLINE) as
well as free-text terms such as “medication adherence” and “medication compliance.” The

42

term “medication compliance” was also included in the search strategy as historically it
was the word used for medication adherence (Ghosh et al., 2017). Using both terms
increased the likelihood of retrieving studies that discussed adherence, whether the exact
term was indexed or not.
To capture studies set in primary care, terms related to this area were used. In
CINAHL, subject headings such as MH “Primary Health Care,” MH “Primary Care Nurse
Practitioners,” and MH “Physicians, Family” were combined with free-text terms like
“primary care,” “family practice,” and “primary care physician.” In Ovid MEDLINE, a
similar approach was taken using the appropriate MH terms. The Boolean operator OR
was used to combine these terms.

43

Figure 3
CINAHL Search strategy

44

45

Figure 4
Ovid MEDLINE Search Strategy

46

Appendix B: Literature Matrix
Table 1
Data Extraction Table
Study
Author:
Chow et al.,
2017
Country:
Australia
Journal:
The Lancet.
Title:
“Quarter-dose
quadruple
combination
therapy for
initial
treatment of
hypertension:
placebocontrolled,
crossover,
randomized
trial and
systematic
review”.

Objective

Study

To assess the
efficacy,
tolerability,
and potential
clinical
benefits of
ultra-low-dose
combination
therapy (Quad
pill) in
improving
blood pressure
control.

Type:
Quantitative
study
Design:
Randomized,
double-blind,
placebocontrolled,
crossover trial

Population
Sample size:
22
Type of
Sampling:
Convenience
Based
(adults with
untreated
hypertension
recruited from
four community
centers in western
Sydney, NSW in
general practices).
Gender
Considerations:
Males 48%
and females 52%

Intervention
Quad pill: single capsule
containing four blood
pressure-lowering
medications at quarter
doses (irbesartan,
amlodipine,
hydrochlorothiazide, and
atenolol) was the
intervention. Participants
received both the quad
pill and placebo for 4
weeks each, with a 2week washout in between.
Participants completed
assessments at baseline,
weeks 4, 6, and 10 weeks.

Key Findings
Type of Results
• Clinical outcomes and
Patient-reported
outcomes
Findings
• Significant reduction in
24-hour systolic BP by
18.7 mmHg in the
intervention group
compared to control
group.
• 24-hour diastolic BP
reduction by 14.2
mmHg in intervention
group compared to
control group.
• All participants
achieved office BP
<140/90 mmHg on the
Quad pill compared to
33% on placebo.
• High medication
adherence and patient
acceptability were
reported.

47
Study

Objective

Study

Population

Author:
Coe et al.,
2020

To evaluate
the Michigan
Pharmacists
Transforming
Care and
Quality
(MPTCQ)
program's
process
outcomes,
clinical
impact, patient
satisfaction,
and
sustainability
of pharmacists
in primary
care.

Type:
Quantitative

Sample size:
9,000 patients
across two
cohorts.

Country:
United States
Journal:
Journal of
Managed Care
& Specialty
Pharmacy
Title:
“Pharmacists
providing care
in statewide
physician
organizations:
findings from
the Michigan
Pharmacists
Transforming
Care and
Quality
Collaborative”
.
Funding:
Blue Cross
Blue Shield of
Michigan
Collaborative
Process
Initiative

Design:
Observational
cohort study.

Type of
Sampling:
Purposive
sampling
(adults with
chronic conditions
such as diabetes,
hypertension, and
hyperlipidemia
were referred by
physicians or
identified through
registry reviews
within 17
participating
physician
organizations in
the MPTCQ
program in
Michigan).
Gender
Considerations:
56% Females in
cohort 1 and 47%
Females in cohort
2.

Intervention
•

•

•

Pharmacists allowed
to initiate, adjust, and
discontinue
medications.
Pharmacists used a
structured
intervention
workflow that
included motivational
interviewing,
adherence aids, and
patient education.
The intervention
emphasized
optimizing
medication therapy.

Key Findings
Type of result:
• Clinical outcome and
Adherence outcome
Findings:
• Significant reductions
in systolic blood
pressure (up to 30
mmHg in severe cases)
• Medication adherence
problems identified and
addressed in 27% in
cohort 1 and 21% of
cohort 2 encounters.

48
Study
Author:
Kassavou et
al., 2021
Country:
United
Kingdom
Journal:
Scientific
Reports
Title:
The feasibility
of PAM
intervention to
support
treatmentadherence in
people with
hypertension
in primary
care: a
randomized
clinical
controlled trial
Funding:
National
Institute for
Health
Research

Objective

Study

Population

To evaluate
the feasibility
and potential
effectiveness
of the
Programme on
Adherence to
Medication (P
AM)
intervention in
improving
medication
adherence and
reducing blood
pressure in
hypertensive
patients.

Type:
Quantitative

Sample size:
101 participants

•

Design:
Randomized
Clinical
Controlled
Trial

Type of
Sampling:
Purposive
sampling (adults
with hypertension
and medication
non-adherence
identified from
electronic medical
records by general
practitioners).

•

Gender
Considerations:
54% Males and
46% females.

Intervention

•

Intervention
consisted of two
components.
First component
included a Very Brief
Intervention (VBI)
delivered by a
practice nurse who
did a short face-toface session with the
patient, explained the
importance of taking
blood pressure
medication, and
helped them sign up
for digital support
(either text messages
or a phone app).
The second
component included
digital intervention
that included 3
months of tailored
digital support
through text
messages or a
smartphone app,
providing reminders,
reinforcing positive
beliefs, and
countering negative
beliefs.

Key Findings
Type of Result:
Clinical outcome and
Adherence outcome.
Key Findings
• Biochemically
validated medication
adherence improved by
20% compared to
control.
• Reduced systolic blood
pressure by 9.16 mmHg
and diastolic by 4.85
mmHg.
• Improved lipid profiles
(cholesterol, LDL,
triglycerides) and
glycated hemoglobin
(HbA1c) in patients
with comorbidities.
• Demonstrated high
feasibility with 100%
uptake and 72%
sustained engagement.

49
Study

Objective

Study

Population

Author:
Levi et al.,
2016

To evaluate
and compare
the adherence
levels between
the fixed-dose
combination
(FDC) of
olmesartan/am
lodipine and
the
extemporaneo
us (two-pill)
combination of
the same drugs
in adult
hypertensive
patients in a
real-world
primary care
setting in Italy.
The goal was
to assess
whether the
FDC improved
adherence to
antihypertensi
ve therapy.

Type:
Quantitative

Sample size:
6,612 patients

Design:
Observational,
Retrospective
cohort design

Type of
Sampling:
Population Based
(adults diagnosed
with hypertension
were identified
through a
population-based
general practice
database in Italy.
Patient exposure
to the drugs was
obtained from the
prescription
records of GPs
and included
patients treated
with either the
fixed-dose
combination of
olmesartan/amlodi
pine or an
extemporaneous
combination of
the same drug
components, with
at least 2 years of
medical history
and 6 months of
follow-up data).

Country:
Italy
Journal:
Journal of
Managed Care
& Specialty
Pharmacy
Title:
“Patient
Adherence to
Olmesartan/A
mlodipine
Combinations:
Fixed Versus
Extemporaneo
us
Combinations”
.
Funding:
Menarini
Farmaceutici
Riuniti

Gender
Considerations:
• FDC Group:
52.2% female
• Extemporane
ous
Combination
Group: 50.8%
female

Intervention
Intervention:
• Fixed-Dose
Combination (FDC):
a single-pill
combination of
olmesartan and
amlodipine at varying
dosages (20/5 mg,
40/5 mg, or 40/10
mg) with a 6 month
follow up period.
Comparator:
• Extemporaneous
Combination:
olmesartan and
amlodipine as
separate pills,
requiring the
concurrent use of
both medications
with a 6 month
follow up period.
• Medication
adherence using the
Proportion of Days
Covered (PDC) over
a 6-month follow-up
period.

Key Findings
Type of Results:
Adherence only outcome
(prescription data).
Key Findings:
• The study found that
55.1% of patients in the
fixed-dose combination
(FDC) group achieved
high adherence 80%
compared to 15.9% in
the extemporaneous
combination group.
• Patients in the FDC
group were 6.65 times
more likely to be highly
adherent (odds ratio =
6.65).

50
Study
Author:
Sarkar et al.
2024
Country:
United States
Journal:
The Journal of
the American
Board of
Family
Medicine
Title:
“Empowering
Low-Income
Patients with
Home Blood
Pressure
Monitors to
Improve
Hypertension
Control”.
Funding:
Texas
Academy of
Family
Physicians
Foundation,
Texas Medical
Association
Foundation,
and Harris
County
Hospital
District
Foundation.

Objective

Study

Population

To evaluate
whether
providing free
home blood
pressure
monitors
improves
hypertension
control and
therapy
adherence, as
measured by
the Therapy
Adherence
Scale (TAS),
focusing on
three domains:
medication
adherence,
dietary
adherence
(reducing
sodium
intake), and
appointment
keeping,
among lowincome,
underserved
patients.

Type:
Quantitative

Sample Size:
200 participants

Design:
Prospective
Randomized
Controlled
Trial

Type of
Sampling:
Convenience
Based (
low-income,
uninsured, and
underserved
adults with
uncontrolled
hypertension in a
community health
center in Texas).
Gender
Considerations:
60% female and
40% males.

Intervention
•

•

Participants in the
intervention group
used the monitors to
record and report
their BP readings
(four times weekly)
during four primary
care visits (two inperson and two
virtual) over six
months. Physicians
used these readings to
guide hypertension
management.
Both groups received
standard care,
including
pharmacologic and
non-pharmacologic
counseling, but the
comparison group did
not have access to
home BP monitors
during the study
period

Key Findings
Type of Results:
Clinical Outcome and
Adherence outcome.
Key Findings:
• 82% of the participants
in the intervention
group achieved BP
control compared to
54% in the control
group.
• Therapy Adherence
Scale scores were
higher in the
intervention group.
• The exact measurement
of medication
adherence improvement
was not reported in the
study. However, it was
noted that among the
three domains assessed
by the Therapy
Adherence Scale,
medication adherence
showed the greatest
improvement in the
intervention group.

51
Study
Author:
Yamane et al.,
2020
Country:
United States
Journal:
Nursing
Forum
Title:
"Assessment
of a patient‐
centered
initiative to
improve
hypertension
management
for adults with
comorbid type
2 diabetes at a
free clinic in
the rural
south".
Funding:
No funding
information
was provided
in the article.

Objective
To evaluate
the impact of a
patientprovider
education
program and
decision aid on
improving
patient
knowledge,
medication
adherence,
provider
guideline
adherence, and
communicatio
n in managing
hypertension
and type 2
diabetes.

Study
Type:
Mixedmethods
Design:
Prospective
mixedmethods

Population

Intervention

Key Findings

Total
Participants: 24

Multifaceted intervention
including:

Type of Results:
Adherence only outcome.

Type of
Sampling:
convenience
Based (adults
aged 18 and older
with diagnosed
with comorbid
hypertension and
type 2 diabetes
mellitus that are
receiving care at
the chronic care
clinic in a free
clinic setting).

•

Sex Distribution:
Female: 79%
Male: 21%

•
•

Patient education
(quiz-based and
focused).
Provider education
Use of a decision aid
(DA) to facilitate.
communication and
guideline-based care.

Key Findings:
• The study found
significant
improvements in
patient knowledge, with
quiz scores increasing
from 60% to 93%.
• Medication adherence
also improved, with
prescription refill rates
rising from 79% to
96%.
• Communication
between providers and
patients was enhanced,
with 72% of patients
reporting active
engagement in shared
decision-making and
76% expressing
confidence in the
treatment's
effectiveness.

52

Table 2
Critical Appraisal Table
Study

Chow et
al., 2017

Strengths

•

•

Coe et
al., 2020

•

•

•

•

Kassavo
u et al.,
2021

•
•
•

Limitations

Novel quad pill strategy
achieved significant blood
pressure reduction with
high adherence and
minimal side effects.
Crossover design
minimized variability,
increasing statistical
power.

•

large-scale study including
over 24,000 pharmacistpatient encounters across
17 physician organizations.
Used real-world data
collected from routine
primary care settings,
which increases the
relevance to everyday
practice.
improved outcomes in
medication adherence and
blood pressure.
Sustainability of the
intervention, shown by the
fact that most
organizations chose to
retain their pharmacists
even after the external
funding ended.

•

Clearly defined research
question.
Appropriate randomization
and low attrition.
Robust outcome measures,
including biochemical
validation.

•

•

•

•

Relevance to Research Question

Quality
of
Evidence

Small sample size
and short follow-up
(10 weeks) limit
generalizability and
long-term safety
assessment.
Conducted in a
single region with
untreated
individuals,
reducing
population
diversity.

Demonstrates the efficacy of a
simplified treatment regimen using a
quad pill, which combines four
antihypertensive agents at low doses.
High adherence rates, minimal side
effects, and significant blood pressure
reductions highlight the potential of
this approach to improve patient
adherence and outcomes.

CASP:
Moderate
Quality

No control group
which makes it
harder to isolate the
pharmacists' effect.
Data self-reported
by pharmacists,
which could
introduce bias.

Evaluates pharmacist interventions
within primary care settings, focusing
on medication management and patient
outcomes, including adherence and
clinical measures like blood pressure
control. Highlights on the collaborative
care model, demonstrating how
integrating pharmacists into primary
care can enhance medication
adherence.

CASP:
High
Quality

Lack of blinding
for participants and
investigators.
Short trial duration
(3 months).

Findings highlight that digital health
interventions can improve medication
adherence in adults with hypertension.

CASP:
High
Quality

53
Study

Strengths

•

Feasible and cost-effective
intervention.

Levi et
al., 2016

•

Large sample size and
robust database.
Valid and objective
adherence measurement.

•

Sarkar et
al., 2024

•

Clear research question
with defined PICO
elements.
Randomized allocation and
comprehensive outcome
reporting.
Significant results showing
intervention effectiveness.

•

Mixed-methods approach
provides comprehensive
insights.
Cost-effective for resourcelimited settings.

•

•

•
•
Yamane
et al.,
2020

•

•

•

•

•

Limitations

Relevance to Research Question

Quality
of
Evidence

Short follow-up
period.
Lack of direct
clinical outcome
measures.

These findings highlight that simplified
regimens, like FDCs, can enhance
patient adherence in antihypertensive
therapy and suggest their early use in
treatment when monotherapy fails, so
as to improve adherence.
The study evaluates the use of free
home blood pressure monitors to
improve medication adherence in
adults with hypertension.

CASP:
High
Quality

The intervention in the study addresses
key barriers to adherence, such as poor
knowledge, communication gaps, and
guideline adherence by integrating
patient-centered education, provider
training, and decision aids.

MMAT:
Moderate
Quality

Lack of blinding
for participants,
investigators, and
outcome assessors.
Small sample size
due to funding
limitations.
Limited by small
sample size.
Short duration
prevented longterm assessment of
outcomes.

CASP:
High
Quality