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Comparative effectiveness of 2 β-blockers in hypertensive patients

Emily D Parker1, Karen L Margolis, Nicole K Trower

  • 1HealthPartners Institute for Education and Research, Minneapolis, Minnesota 55440-1524, USA. Emily.D.Parker@Healthpartners.com

Archives of Internal Medicine
|August 29, 2012
PubMed

Insights

For patients with hypertension, atenolol and metoprolol tartrate showed no significant difference in preventing cardiovascular events. This study highlights the utility of large registries for comparative effectiveness research in hypertension management.

Area of Science:

  • Cardiology
  • Pharmacology
  • Hypertension Management

Background:

  • Established efficacy of certain beta-blockers post-myocardial infarction (MI) and for heart failure (HF).
  • Recent questions regarding beta-blocker effectiveness for cardiovascular (CV) event prevention in hypertension.
  • Uncertainty whether observed effects are a class-wide phenomenon for beta-blockers.

Purpose of the Study:

  • To compare the effectiveness of atenolol versus metoprolol tartrate in preventing incident cardiovascular events.
  • To evaluate these outcomes in a large cohort of patients with newly initiated beta-blocker therapy for hypertension.
  • To determine if observed differences are a class effect or specific to individual beta-blockers.

Main Methods:

  • Utilized electronic medical record and health plan data from the Cardiovascular Research Network Hypertension Registry (2000-2009).
  • Compared incident MI, HF, and stroke in new beta-blocker users without prior CV disease.
  • Employed Cox proportional hazards regression with standard covariate adjustment and propensity score-matching.

Main Results:

  • No statistically significant differences in hazard ratios for MI, HF, or stroke between metoprolol tartrate and atenolol users.
  • Hazard ratios for metoprolol tartrate users were 0.99 (MI), 0.99 (HF), and 0.99 (stroke) compared to atenolol.
  • Propensity score matching analysis of 22,352 patients yielded similar non-significant findings.

Conclusions:

  • Atenolol and metoprolol tartrate demonstrated comparable effectiveness in preventing incident CV events in hypertensive patients.
  • Findings suggest no significant difference between these two beta-blockers for the studied outcomes.
  • Large patient registries are valuable for comparative effectiveness research in hypertension when randomized trials are limited.
Abstract

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