Predictors for Attaining Maximal-Range Recommended Doses of Beta-Blockers and Angiotensin-Renin Inhibitors in Patients with Reduced Left Ventricular Ejection Fraction Treated in a Community-Based, Heart-Failure Clinic

Aims: Despite prior studies which have clearly demonstrated the efficacy of pharmacological therapies titrated to target doses in improving the poor outcomes of heart failure (HF) patients with reduced ejection fraction (HFrEF), patients are frequently treated with sub-optimal doses. We aim to determine predictors for attaining maximal-range (≥75% of maximal dose) recommended doses of angiotensin converting enzyme-inhibitors (ACE-Is), angiotensin receptor blockers (ARBs) and beta blockers (BBs) in patients with HFrEF.

Methods: We examined treatment in patients with left ventricular ejection fraction (LVEF) ≤40% who attended ≥3 visits in the up-titration treatment program of a community-based, dedicated heart-failure clinic.

Results: The majority of the 215 patients were males with a median age at presentation of 73 years (25^th, 75^th interquartile range 65, 78) and LVEF of 30% (25%, 35%). The up-titration program increased the doses of ACE-Is/ARBs from 25% (25%, 50%) of the maximally-recommended dose to 58% (25%, 100%) and from 25% (25%, 50%) to 50% (25%, 100%) for BBs. Higher body mass index (BMI) was found as the sole, independent predictor for achieving maximal-range doses of ACE-I/ARBs (odds ratio (OR) 1.13 (1.05, 1.22), p=0.001). More patients achieved maximal-range doses of ACEIs/ARBs as BMI increased, with a sharp decline in the highest obesity category (BMI ≥40 m²/kg). Diabetes mellitus (OR 2.6 (1.34, 5.19), p=0.005) was an independent predictor for attaining maximal-range doses of BBs, whereas women were less likely to do so (OR 0.34 (0.13, 0.90), p=0.031).

Conclusion: The sole predictor for achieving maximal-range doses of ACE-Is/ARBs in HFrEF outpatients in an up-titration treatment program was higher BMI. These findings are in concordance with the “obesity paradox”. Diabetes mellitus independently predicted attaining maximal-range doses of BBs, whereas women were significantly less likely to do so. These findings may serve as benchmarks for up-titration programs.