Guideline-directed medical therapy for heart failure: Real-world evidence in one Latin-American center

Background
Despite recommendations from clinical practice guidelines to initiate four drug classes in patients with heart failure (HF) with reduced ejection fraction, information on real-world implementation remains limited. This study evaluated the medications initiated and titrated, the time until the optimal treatment tolerated, pharmacological profiles, patient's adherence, and causes of non-use of guideline directed-medical therapy (GDMT) in a cohort of patients with HF.
Methods
A retrospective cohort study was conducted on patients treated in a heart failure program in Colombia. Optimal treatment tolerated was defined as that achieved within 6 months of follow-up. Medication adherence was assessed using the 4-item Morisky-Green scale.
Results
A total of 471 patients were included, with a median age of 76 years, 56.9 % male, and a median left ventricular ejection fraction of 35 %. Overall, 43.9 % of patients were on GDMT quadruple therapy, with a median time to optimal tolerated treatment of 57 days (IQR: 1–133). More than 90 % reached target doses with mineralocorticoid receptor antagonists and SGLT2 inhibitors, while less than 50 % achieved it with beta-blockers and renin-angiotensin-aldosterone system inhibitors. Adherence, according to the Morisky-Green scale, was 89.9 % and main causes of non-adherence were lack of social-family support (46.8 %) and forgetting to take medication (44.7 %).
Conclusions
In this real-world study of patients with HF, GDMT use rates were higher than those previous national registries. However, the medication doses were lower than those recommended by clinical guidelines. Identifying and quantifying adherence barriers in low- or middle-income countries is essential for implementing recommendations in clinical practice.