Utilisation and optimisation of beta-adrenergic receptor blockers over a 6-month period among chronic heart failure patients with reduced ejection fraction

Background. Beta-adrenergic receptor blocker (BARB) drugs are a wide range of medicines that are used in various conditions, including chronic heart failure (HF). Several studies have reported a wide-ranging inappropriate use of evidence-based beta-blockers (EBBBs) in chronic HF in both inpatients and outpatients. Objectives. To assess the utilisation and optimisation of EBBBs among patients with HF who presented with a reduced ejection fraction (HFrEF). Methods. A hospital-based retrospective cross-sectional study was carried out at the Adult University Teaching Hospital (AUTH), in Lusaka, Zambia, where patient medical files for the period of 1 July 2018 to 31 July 2021 were reviewed. Patient information, including file number, age, sex, type of BARB and the dose used, was recorded on the developed and validated checklist. Multivariable regression analysis was performed to identify factors associated with utilisation of BARBs. Results. Of the 173 medical records reviewed, BARBs were utilised in 101 (58.4%) patients. Among the patients who utilised BARBs, 96 (95.0%) were taking EBBBs, while the rest (n=5, 5.0 %) were taking atenolol, which is a non-EBBB. Among the patients who were on EBBBs, none of them received the optimal dose. Age =65 years (adjusted odds ratio (aOR) 0.3, 95% confidence interval (CI) 0.17 - 0.64), previous hospitalisation (aOR 0.3, 95% CI 0.13 - 0.51) and furosemide dose =40 mg ( aOR 0.4, 95% CI 0.21 - 0.64) were significantly associated with lower likelihood of BARB utilisation. New York Heart Association (NYHA) class II (aOR 3.4, 95% CI 1.08 - 10.7), NYHA class III (aOR 4.8, 95% CI 1.65 - 13.7) and patients using at least 5 medications (aOR 5.0, 95% CI 2.91 - 8.77) were independent predictors of BARB utilisation. Conclusion. This study showed that 95.0% of chronic HF patients were utilising EBBBs, and none received the optimal dose as recommended in the guidelines. Pharmacotherapy with EBBBs should be optimised among patients with chronic HfrEF, as these drugs reduce both morbidity and mortality.