Guideline-directed medical therapy (GDMT) remains central to heart failure management, yet real-world uptake of complete multidrug regimens remains uncertain. A retrospective observational cohort study published in BMJ Open evaluated prescription patterns and optimization of GDMT in patients with heart failure with reduced ejection fraction (HFrEF) in Singapore. The study included 3,999 adults hospitalized between 2020 and 2022 with a first heart failure-related admission and left ventricular ejection fraction (LVEF) ≤40% across seven public hospitals. Patients with absolute contraindications to specific GDMT classes were excluded from eligibility calculations.

Among eligible patients, 80%–99% met criteria for individual GDMT drug classes, yet only 29% received quadruple therapy at discharge in 2022. However, only 29% received quadruple therapy at discharge in 2022, defined as an ACE inhibitor (ACEi), angiotensin receptor blocker (ARB) or angiotensin receptor–neprilysin inhibitor (ARNI), together with a β-blocker, mineralocorticoid receptor antagonist (MRA), and sodium-glucose cotransporter-2 (SGLT2) inhibitor. Prescription rates at discharge were 67% for ACEi/ARB/ARNI, 89% for β-blockers, 40% for MRAs, and 46% for SGLT2 inhibitors. More than 90% of patients receiving ACEi/ARB/ARNI and β-blockers were prescribed ≤50% of target doses. 

At 6 months, prescriptions declined for ACEi/ARB/ARNI (−16%), β-blockers (−26%), and MRAs (−7%), while SGLT2 inhibitor use increased. Older age and CKD stage 3a–4 were associated with lower quadruple therapy use. Significant institutional variation in quadruple therapy prescribing was also observed across participating hospitals.

Overall, GDMT uptake, dose optimization, and persistence remained limited despite high eligibility. The findings highlight persistent gaps in GDMT initiation, dose optimization, and treatment persistence among patients with HFrEF in Singapore.