A Systematic Review Uncovering Modifiable Influences on Statin Adherence

Patient Prefer Adherence. 2025 Jan 4:19:29-48. doi: 10.2147/PPA.S502645. eCollection 2025.

Abstract

Statins are effective in reducing cardiovascular disease (CVD) risk, but adherence rates remain low globally. Understanding and addressing modifiable influences on adherence is key to improving outcomes. Existing reviews have methodological limitations, often failing to integrate qualitative and quantitative data or consider specific barriers to statin adherence. This systematic review aimed to identify modifiable barriers and facilitators to statin adherence using the Theoretical Domains Framework (TDF). A comprehensive search of Embase, MEDLINE, PsycINFO, and CINAHL was conducted, covering studies from January 1998 to November 2023. Data were coded to TDF domains and synthesized to identify specific influences on adherence. The nature of the evidence (qualitative or quantitative) was recorded for each influence, and variations among patient groups were noted. Seventy studies from 20 countries were included, with only one focused on ethnic minorities. The most commonly identified domains affecting adherence were "Beliefs about Consequences", "Knowledge", 'Environmental Context and Resources', and "Social Influences". Key factors included knowledge of disease, perceived disease threat, perceived benefits of statins, and patient-provider communication and trust. While side effects had inconsistent associations with adherence, forgetfulness was mainly addressed in quantitative studies, and social influences were highlighted in qualitative research. This review identified modifiable factors that could improve statin adherence. Future research should focus on addressing barriers faced by underrepresented groups to create more inclusive and effective interventions that enhance patient support and communication for better health outcomes.

Keywords: dyslipidaemia; medication adherence; psychological determinants; theoretical domains framework.

Plain language summary

People are prescribed statins to prevent strokes and heart attacks. This study combines findings from previous studies to understand why many people do not take statins as prescribed. Common barriers to taking statins included not thinking being at risk of strokes and heart attacks, believing statins are harmful, experiencing side effects and poor communication and trust with healthcare professionals. Common things encouraging statin taking included thinking statins have benefits, having cholesterol levels checked, routines and methods to remember statin intake and having ways of dealing with side effects.

Publication types

  • Review

Grants and funding

This research was funded by the National Institute for Health and Care Research (NIHR) Research for Patient Benefit (RfPB) Programme (Ref. NIHR205407) and infrastructure support for this study was provided by the NIHR North-West London Patient Safety Research Collaboration (NIHR NWL PSRC, Ref. NIHR204292); The views expressed are those of the author(s) and not necessarily those of the NIHR or the Department of Health and Social Care. Additionally, this work was supported by the Economic and Social Research Council (ESRC) through the London Interdisciplinary Social Science Doctoral Training Partnership (LISS DTP). The first author’s role on this work is also funded by the National Agency for Research and Development (ANID) / Scholarship Program / DOCTORADO BECAS CHILE/2022 - 72220048. The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; or decision to submit the manuscript for publication.