Adherence and persistence to heart failure guideline-directed medical therapy: A systematic review of studies based on electronic healthcare data.

Background: Heart failure (HF) significantly impacts global morbidity, mortality, and healthcare costs. Effective treatment involves multiple guideline-directed medical therapies, such as beta-blockers, angiotensin-converting enzyme inhibitors, and mineralocorticoid receptor antagonists, angiotensin receptor-neprilysin inhibitor and sodium-glucose cotransporter 2 inhibitors. However, medication adherence and persistence in HF patients are often suboptimal, negatively influencing clinical outcomes. This systematic review assesses medication adherence and persistence among HF patients and their relationship to clinical outcomes.

Methods: A systematic review following PRISMA guidelines was conducted, evaluating observational studies utilizing electronic healthcare databases published between 1990 and 2024. Studies reporting adherence or persistence to HF pharmacological treatments, measured by pharmacy claims or electronic health records, were included. Primary adherence (initial dispensing), secondary adherence (continued refilling), and persistence (duration until medication discontinuation) were analyzed.

Results: Fifty-two studies involving 2,001,178 HF patients were reviewed. No studies adequately assessed primary adherence. Secondary adherence was predominantly evaluated using Proportion of Days Covered or Medication Possession Ratio, with adherence generally below optimal levels (<80 %). Medication adherence declined significantly with increased regimen complexity and over extended periods. Persistence rates were notably lower in long-term follow-ups, especially with mineralocorticoid receptor antagonists. Higher medication adherence and persistence consistently correlated with reduced hospitalizations, emergency department visits, and mortality rates. Methodological heterogeneity across studies precluded the feasibility of a meta-analysis.

Conclusions: Medication adherence and persistence among HF patients remain suboptimal, particularly with complex, multi-drug regimens and prolonged treatments. Improved adherence was correlated with better clinical outcomes, underscoring the need for standardized adherence measures and targeted interventions to enhance patient outcomes.