Sulfonylureas and beta-blockers, when used together may raise risk of severe hypoglycemia

"Patients with type 2 diabetes and heart failure or hypertension could consider using an alternative cardiovascular or antidiabetes drug, especially in cases where the baseline hypoglycemia risk is elevated," the researchers wrote in their study.

Sulfonylureas are the drugs that strongly increase the risk of this potentially fatal adverse effect (hypoglycemia). Their hypoglycemic potential among sulfonylureas users needs to be better understood. Previous studies have linked the use of β-blockers with an increased hypoglycemia risk. Cardioselectivity of β-blockers is suggested to affect the risk. Jenny Dimakos from the Department of Medicine at McGill University in Montreal, Quebec, Canada, and colleagues aimed to evaluate the potential association between concomitant use of sulfonylureas and β-blockers versus the use of sulfonylureas alone and the risk of severe hypoglycemia in a population-based cohort study.

For this purpose, the researchers included patients initiating sulfonylureas between 1998 and 2020 using the U.K. Clinical Practice Research Datalink Aurum, those with β-blocker use in the past six months were excluded. Time-dependent Cox models estimated hazard ratios (HRs) of severe hypoglycemia (hospitalization with or death from hypoglycemia) associated with current concomitant sulfonylureas and β-blockers use compared with current sulfonylurea use alone, adjusted for baseline confounders. They also compared the current concomitant use of sulfonylureas and non-cardioselective versus cardioselective β-blockers.

The researchers reported the following findings:

• The cohort included 252,869 initiators of sulfonylureas (mean age 61.3 years; 43% female) who were followed for a median of 7.9 years. The crude incidence rate of severe hypoglycemia was 7.8 per 1,000 per year.
• Concomitant use of sulfonylureas and β-blockers was associated with an increased risk of severe hypoglycemia compared with sulfonylurea use alone (HR 1.53).
• There was no difference in the risk between the concomitant use of sulfonylureas and non-cardioselective β-blockers and concurrent use of sulfonylureas and cardioselective β-blockers (HR 0.95).

"β-blockers, when used concurrently with sulfonylureas, could further raise the risk of severe hypoglycemia," the researchers concluded. "In this regard, β-blocker cardioselectivity did not play a major role."

Reference:

Jenny Dimakos, Ying Cui, Robert W. Platt, Christel Renoux, Kristian B. Filion, Antonios Douros; Concomitant Use of Sulfonylureas and β-Blockers and the Risk of Severe Hypoglycemia Among Patients With Type 2 Diabetes: A Population-Based Cohort Study. Diabetes Care 2022; dc221584. https://doi.org/10.2337/dc22-1584