Evaluating Patient Adherence to Antihypertensive Therapy in Community Pharmacies

Thesis Abstract

Hypertension remains a leading contributor to cardiovascular morbidity and mortality worldwide, with patient adherence to prescribed antihypertensive therapy significantly influencing treatment outcomes. Despite the availability of effective medications, poor adherence in community pharmacy settings continues to undermine hypertension control, leading to increased healthcare costs and adverse health events. This study aims to evaluate the levels, determinants, and barriers of patient adherence to antihypertensive therapy within community pharmacy contexts, seeking to inform strategies to optimize medication-taking behaviors and improve health outcomes. The specific objectives include identifying demographic, socioeconomic, and clinical factors associated with adherence, assessing patients’ knowledge and perceptions of antihypertensive medications, and exploring the role of community pharmacists in promoting adherence. The research employs a cross-sectional observational design, integrating both quantitative and qualitative data collection methods. The target population comprises hypertensive patients aged 30–70 years accessing community pharmacies in the metropolitan region. A sample size of 400 patients was computed using Cochran’s formula to ensure statistical power, employing stratified random sampling to capture diverse demographic groups. Data collection instruments included structured questionnaires for quantitative measurement of adherence levels, based on the 8-item Morisky Medication Adherence Scale (MMAS-8), as well as in-depth semi-structured interviews with a purposively selected subset of 30 patients and 10 community pharmacists to explore contextual barriers and facilitators. To ensure validity and reliability, questionnaires were pre-tested in a comparable setting, with Cronbach’s alpha exceeding 0.80, and interview protocols were subjected to peer review. Data analysis involved descriptive statistics to determine adherence prevalence, followed by inferential techniques including multiple logistic regression to identify independent predictors of high or low adherence. Thematic analysis was applied to qualitative interview transcripts to extract nuanced insights into patients’ perceptions and pharmacists' roles. Additionally, the study applied the Health Belief Model (HBM) and the Theory of Planned Behavior (TPB) as theoretical frameworks to interpret behavioral determinants influencing medication adherence. Expected findings suggest that approximately 45% of patients exhibit high adherence, while 25% demonstrate poor adherence, with low adherence significantly associated with factors such as medication side effects, forgetfulness, medication costs, and limited patient-pharmacist communication. The qualitative component is anticipated to reveal perceived barriers like lack of understanding of hypertension consequences and insufficient counseling, alongside facilitators such as personalized pharmacist counseling and reminder systems. These insights are expected to elucidate actionable intervention points to enhance adherence. The study contributes to the knowledge base by providing context-specific evidence on adherence behaviors in community pharmacy settings, highlighting the importance of tailored pharmacist interventions and patient education. It underscores the multifaceted nature of medication adherence and the need for integrated approaches encompassing behavioral theories and practical strategies. The findings will inform policymakers, healthcare providers, and community pharmacists to develop targeted adherence support programs, promoting sustainable hypertension management. The main conclusion emphasizes that improving adherence requires a collaborative approach involving pharmacists, patients, and healthcare systems, with practical recommendations including training pharmacists in patient-centered counseling, implementing reminder systems, and intensifying health literacy efforts. The study advocates for future longitudinal research to evaluate the effectiveness of adherence-promoting interventions over time and across different healthcare settings. Overall, this research provides a comprehensive understanding of adherence determinants, fostering evidence-based strategies to optimize antihypertensive therapy outcomes in community pharmacies.