Beta-blockers used in cardiac failure and blood glucose level impairment - a literature review

Introduction: Blood sugar level impairment, especially diabetes mellitus (DM) is a significant problem. DM leads to many serious complications. Patients suffering from cardiac failure (HF) and diabetes have a risk of hospitalization increased 1.5 times compared to the control group without DM. That is why it is very important to keep appropriate glycemic control. β-blockers, are considered to cause a blood glucose level impairment. The relationship between the use of β-blockers and the development of DM is one of the most interesting and controversial issues in diabetology. Despite many benefits, some doctors are reluctant to prescribe β-blockers because of perceived negative metabolic effects.Aim of study: The purpose of the study was to review the literature describing oral β-blockers, used in HF, influence on glucose metabolism and to discover the best β-blocker treatment for cardiac failured diabetics and prediabetics. Methods: A systemic review was conducted using PubMed, ScienceDirect, Google Scholar databases. The search strategy was based on the following terms: beta-blocker, blood glucose level, metoprolol, nebivolol, carvedilol, bisoprolol. Results: β-blockers differ in terms of their mechanism of action and their effects on glucose metabolism. Metoprolol is associated with a worsening of glucose and lipid control. Bisoprolol have a neutral impact on glucose metabolism. Vasodilating β-blockers may improve glycemic profile.Conclusions: All four β-blockers used in HF have similar blood pressure lowering effect but different metabolic effect. Metoprolol should not be used as a drug of choice in patients with impaired glucose metabolism. Bisoprolol, nebivolol or carvedilol may be recommended as a drug of choice in patients with cardiac failure and impaired carbohydrate metabolism. The choice between bisoprolol and vasodilating β-blockers in patients with glycemic disorders is still an unresolved issue.