A Decade in Review: A Systematic Analysis of Factors Affecting Medication Adherence Among Geriatric Patients with Chronic Diseases Using the Health Belief Model (2014-2024)

Abstract

Background: Medication adherence among older adults is an important determinant of chronic disease management outcomes. Since the publication of Yap et al.’s 2016 review, numerous new studies have emerged, requiring an updated synthesis to reflect transitioning factors in a rapidly aging and medically complex global population. Given the unique challenges that older adults are faced with—including polypharmacy, cognitive decline, cultural influences, and shifting beliefs about illness—an updated synthesis based on the Health Belief Model (HBM) offers a comprehensive lens for understanding behavioral adherence’s barriers and facilitators that can specifically be targeted with evidence-based interventions. Methods: This systematic review is an update of Yap et al.’s 2016 review, incorporating literature published between 2014 and 2024. The aim was to identify factors influencing medication adherence among adults aged 65 and older with at least one of the most common chronic conditions—namely hypertension, diabetes mellitus, and dyslipidemia. Two electronic databases (OVID-MEDLINE and Embase) were searched for peer- reviewed studies reporting adherence-related factors among older adults. From 25,016 records, 42 studies met the inclusion criteria. A thematic synthesis was performed, categorizing factors into five domains used by Yap et al. (2016): patient-related, medication-related, physician-related, system-based, and other contextual factors. These domains were then mapped into the six constructs of the Health Belief Model: perceived susceptibility, perceived severity, perceived benefits, perceived barriers, cues to action, and self-efficacy. Results: Key findings emphasized the central role of perceived barriers such as cost, complexity of regimens, and forgetfulness. Perceived facilitators included belief in medication efficacy, supportive cues (e.g., reminders or health worker interventions), and trust in healthcare providers. The updated literature confirmed the persistence of previously identified barriers while highlighting newer insights into the importance of self-efficacy and individualized health beliefs in adherence behavior. Conclusion: The updated evidence reveals important opportunities for intervention through personalized care, education, and tailored strategies to enhance self-efficacy and reduce perceived barriers among older adults. Simultaneously, strengthening perceived facilitators—such as trust in providers and belief in treatment efficacy—can further improve medication adherence. These findings underscore the utility of the Health Belief Model in guiding adherence-focused interventions for aging populations with chronic conditions.