Prevalence and determinants of adherence to statin therapy: a systematic review and meta-analysis

Abstract

Adherence to statin therapy remains suboptimal and is significantly influenced by demographic and clinical factors. Targeted strategies are needed to improve adherence, particularly in high-risk groups. Adherence to statin therapy is a key determinant of cardiovascular risk reduction, yet real-world adherence remains uncertain across populations. We conducted a systematic review and meta-analysis to estimate the prevalence of good adherence to statin monotherapy and to identify demographic and clinical factors associated with adherence among adults prescribed lipid-lowering therapy for the prevention of atherosclerotic cardiovascular disease. PubMed and Scopus were searched through May 2025 for randomized controlled trials, cohort, nested case control, and cross-sectional studies assessing statin adherence. Data were extracted on study design, participant characteristics, comorbidities, adherence measurement methods and duration, and statin type. Study quality was assessed using the Newcastle-Ottawa Scale, and risk of bias in randomized trials was evaluated with the Cochrane RoB 2 tool. Random-effect meta-analysis, along with subgroup and sensitivity analyses by follow-up duration, adherence thresholds, and study quality, was performed. Seventy-six studies including 5,898,141 participants with a median follow-up of 24 months were analysed. The pooled prevalence of good adherence (≥80% medication use) was 62.4% (95% CI: 58.3–66.5%), with lower adherence in primary prevention compared with secondary prevention settings. Lower adherence was associated with female sex, Black race, smoking, depression, and heart failure, whereas higher adherence was observed among older adults, those with myocardial infarction or hypertension, individuals with multiple comorbidities, and patients receiving polypharmacy. Primary non-adherence was not reported in any included study, and subgroup and sensitivity analyses showed consistent findings. Overall, statin adherence remains suboptimal and is strongly influenced by demographic and clinical factors, underscoring the need for targeted strategies to improve adherence, particularly among high-risk groups.