National Institute of Health

Researchers associate third-generation b-blockers with an inferior protective effect against stroke in patients with high blood pressure

Hypertension or high blood pressure can cause serious physiological consequences such as organ damage if not managed properly. While b-blockers are routinely prescribed as first-line treatment, evidence for their safety and efficacy is lacking. Now, a new study by Korean researchers identifies higher risk of stroke for patients on third-generation b-blockers compared with other recommended medications, providing important insights in the proper treatment and control of hypertension.

Researchers from KNIH reveal in a new study that, contrary to expectations, third-generation b-blockers do not provide enough protection against stroke in patients of hypertension.

Photo credit: Horacio Selva from Shutterstock.

Keeping hypertension or high blood pressure in check often requires not only adopting a series of dietary and lifestyle changes but also opting for standard prescription-based medications. Clinicians routinely prescribe b-blockers as first-line treatment for lowering blood pressure. However, their efficacy and safety has remained unverified so far. This is particularly concerning in light of the fact that b-blockers have been shown to be inferior compared with other medications recommended for hypertension, such as angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), calcium-channel blockers (CCBs), and thiazide-like diuretics (TDs).

One explanation for the reported inferiority has been that the previous studies have only considered second-generation b-blockers, which do not produce vasodilating effects (the dilatation of blood vessels to reduce blood pressure). It is postulated that third-generation b-blockers, which produce vasodilation, could fare better in treating hypertension compared to their second-generation counterparts.

To verify this claim, a group of international researchers, led by Professor Sungha Park and Assistant Professor Seng Chan You from Korea, recently conducted a study to determine the safety and effectiveness of third-generation b-blockers compared with atenolol, as part of a Large-Scale Evidence Generation and Evaluation Across a Network of Databases for Hypertension (LEGEND-HTN) project. This study was supported by the Korean Centers for Disease Control and Prevention (2018-ER6302-01 to S. Park) and was published in the journal Hypertension.

In their study, the research team accessed three U.S. databases containing administrative claims and electronic health records of eligible patients on third-generation b-blockers between 2001 and 2018. Using specialized quantitative techniques, the team estimated the risk for acute myocardial infarction, stroke, hospitalization due to heart failure, and other metabolic complications among these patients and combined the estimates across databases using a random-effects meta-analysis model.

Interestingly, the findings, based on the analyses of 118,133 patients on carvedilol and nebivolol and 267,891 patients on atenolol, revealed that the estimated risks for acute myocardial infarction, stroke, hospitalization due to heart failure, and most other metabolic complications were similar to atenolol for all the third-generation β-blockers. However, contrary to the expectation, the third-generation β-blockers were associated with an inferior protective effect against stroke. “Patients on third-generation β-blockers showed, in fact, a greater risk of stroke compared to those administered ACE inhibitors and TDs,” explains Prof. Park.

Although not without limitations, the study undoubtedly raises a red flag regarding the recommendation of third-generation β-blockers as first-line therapy, providing an important cue to clinicians, biomedical researchers, and medical associations. However, we should keep in mind that beta blockers are still important first-line treatment for ischemic heart disease, heart failure and tachyarrhythmia. “Given the prevalence of β-blockers as a first-line anti-hypertensive medication, we hope that our findings would lead to a better control of hypertension, and facilitate a decrease in the prevalence of stroke worldwide,” concludes Dr. Chan You.

That, certainly, is a consequence to look forward to!

Reference

About National Institute of Health in Korea

The Korea National Institute of Health (KNIH), one of the major operating components of the Korea Disease Control and Prevention Agency, leads the nation’s medical research. Over the past seven decades, the KNIH has made unwavering efforts to enhance the public’s health and innovate biomedical research. The KNIH seeks to eradicate diseases and make people healthier. The KNIH establishes a scientific basis and evidence underlying health policy as well as provides national research infrastructures. We also promote public health research. To this end, we make efforts to enrich a health research environment by granting funds to research projects and keeping our resources, data, and facilities more open and accessible to researchers.

Website: http://www.nih.go.kr/eng/

About Professor Sungha Park and Dr. Seng Chan You

Dr. Sungha Park is a Professor in the Division of Cardiology at Yonsei University College of Medicine, South Korea. One of the most prominent and well-cited Korean researchers working in the field of hypertension, Dr. Park has over 300 publications to his credit.

Dr. Seng Chan You is an Assistant Professor in the Department of Preventive Medicine at Yonsei University College of Medicine. He received his Ph.D. at the Department of Biomedical Informatics, Ajou University, South Korea, and recently received the 2021 Wunsch Young Investigator Award. He has published 109 papers with over 1100 citations to his credit.