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Do losartan and atenolol have differential effects on BNP and central haemodynamic parameters?

Justine Davies1, Elaine Carr, Margaret Band

  • 1Division of Medicine and Therapeutics, Ninewells Hospital and Medical School, Dundee, DD1 9SY, UK. j.i.davies@dundee.ac.uk

Journal of the Renin-Angiotensin-Aldosterone System : JRAAS
|March 10, 2006
PubMed

Insights

Losartan reduced brain natriuretic peptide (BNP) more than atenolol, suggesting a potential benefit beyond blood pressure lowering. However, no significant differences in central or peripheral hemodynamics were observed between the two drugs.

Area of Science:

  • Cardiovascular Pharmacology
  • Hypertension Management
  • Clinical Trials

Background:

  • Angiotensin-converting enzyme inhibitors (ACE-Is) and angiotensin II receptor blockers (ARBs) may offer hemodynamic benefits beyond brachial blood pressure reduction.
  • Investigating differential effects of losartan (ARB) versus atenolol (beta-blocker) on hemodynamics and brain natriuretic peptide (BNP) is crucial for understanding treatment benefits.
  • The Losartan Intervention For Endpoint reduction in hypertension (LIFE) study provides a context for comparing these antihypertensive agents.

Purpose of the Study:

  • To compare the effects of losartan and atenolol on central and brachial hemodynamics.
  • To assess the differential impact of losartan and atenolol on brain natriuretic peptide (BNP) levels.
  • To determine if hemodynamic differences contribute to the observed benefits of losartan over atenolol.

Main Methods:

  • A crossover study involving 17 patients, randomized to receive four months of losartan and atenolol.
  • Primary outcome measures included BNP levels and Augmentation Index (AIx) for central hemodynamics.
  • Secondary measures included brachial pulse wave velocity (PWV) and time to reflected wave (Tr) to assess vascular stiffness.

Main Results:

  • BNP levels were significantly lower with losartan compared to atenolol (p=0.007).
  • Augmentation Index (AIx) was lower with losartan (p=0.03), but this did not remain significant after adjusting for heart rate (p=0.09).
  • Heart rate was significantly lower with atenolol (p=0.03); no significant differences were found in brachial PWV or Tr between treatments.

Conclusions:

  • The observed benefits of losartan compared to atenolol in the LIFE trial may be attributed to its effect on reducing BNP.
  • No differential effect on central or peripheral hemodynamics was detected between losartan and atenolol in this study.
  • Further research is needed to fully elucidate the mechanisms behind the differential effects of ARBs and beta-blockers on cardiovascular outcomes.
Abstract

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