Blood pressure and plasma renin activity responses to different strategies to inhibit the renin-angiotensin-aldosterone system during exercise

• Main Authors: Bryan Williams, Fabio Baschiera, Peter S Lacy, Jaco Botha, Margaret F Prescott, Patrick Brunel
• Format: Article
• Language: English
• Published: Hindawi - SAGE Publishing 2013-03-01
• Series: Journal of the Renin-Angiotensin-Aldosterone System
• Online Access: https://doi.org/10.1177/1470320312454766

Objective: The effect of two different strategies for renin–angiotensin–aldosterone system (RAAS) blockade; direct renin inhibition (DRI) versus angiotensin receptor blockade (ARB) on blood pressure (BP) and plasma renin activity (PRA) was compared during exercise. Methods: Hypertensive adults were randomised to aliskiren (300 mg once daily, n =33) or valsartan (320 mg once daily, n =35). BP and PRA were measured during treadmill exercise (Bruce protocol), at baseline, end of treatment (eight weeks), and after treatment withdrawal (48 hours after last dose). Results: After eight weeks treatment, Aliskiren inhibited PRA (>80%) at rest and during exercise, with inhibition remaining undiminished 48 hours after treatment withdrawal. In contrast, valsartan increased PRA at rest, and more-so during exercise (>400%). Angiotensin receptor blockade, as indicated by PRA increase, was reduced, 48 hours after valsartan treatment withdrawal, suggesting more sustained RAAS blockade with aliskiren. Despite divergent effects on PRA, similar exercise-induced changes in BP were seen. The primary outcome, the rise in systolic BP from rest to peak exercise (baseline to after treatment withdrawal) did not differ between treatments ( p =0.25). Conclusion: Measurement of PRA is a more sensitive index of RAAS blockade than the BP response during exercise. Furthermore, after treatment withdrawal, aliskiren provides more sustained RAAS inhibition than valsartan at rest and during exercise.