Salt restriction vs. angiotensin receptor blockade in hypertension

January 01, 0001

Salt restriction vs. angiotensin receptor blockade in hypertension

These Dutch researchers examined the effects of dietary sodium restriction or angiotensin receptor blockers in patients already taking angiotensin converting enzyme (ACE) inhibitors. Specifically they looked at the effects on proteinuria and blood pressure control. They performed a multicentre crossover randomized controlled trial, recruiting 52 patients with non-diabetic nephropathy. Enrollees received lisinopril 40mg/day plus, in random order, valsartan 320 mg/day or placebo coupled with low sodium diet or regular sodium diet. The medication interventions were double blind but the dietaryinterventions were open label.

The researchers found: "The reduction of proteinuria by the addition of a low sodium diet to ACE inhibition (51%) was significantly larger than the reduction of proteinuria by the addition of angiotensin receptor blockade to ACE inhibition (21%) and was comparable (not significant after Bonferroni correction) to the reduction of proteinuria by the addition of both angiotensin receptor blockade and a low sodium diet to ACE inhibition (62%). Mean systolic blood pressure was 134 mm Hg during ACE inhibition plus a regular sodium diet. Mean systolic blood pressure was not significantly altered by the addition of angiotensin receptor blockade (131mm Hg) but was reduced by the addition of a low sodium diet (123 mm Hg) and angiotensin receptor blockade plus a low sodium diet (121 mm Hg) to ACE inhibition. The reduction of systolic blood pressure by the addition of a low sodium diet (7%) was significantly larger than the reduction of systolic blood pressure by the addition of angiotensin receptor blockade (2%) and was similar to the reduction of systolic blood pressure by the addition of both angiotensin receptor blockade and low sodium diet (9%), to ACE inhibition."

The researchers concluded: "Dietary sodium restriction to a level recommended in guidelines was more effective than dual blockade for reduction of proteinuria and blood pressure in non-diabetic nephropathy. The findings support the combined endeavours of patients and health professionals to reduce sodium intake."

This small study stresses the importance of sodium restriction for treating hypertension and non-diabetic nephropathy

For the full abstract, click here.

BMJ 343:d4366, 26 July 2011 © 2011 BMJ Publishing Group Ltd.
Moderate dietary sodium restriction added to angiotensin converting enzyme inhibition compared with dual blockade in lowering proteinuria and blood pressure: randomised controlled trial. Maartje C J Slagman, Femke Waanders, Marc H Hemmelder, et al. Correspondence to G D Laverman?: [email protected]

Category: K. Circulatory, U. Urinary System. Keywords: sodium, salt, angiotensin receptor blockers, hypertension, proteinuria, crossover randomized controlled trial, journal watch.
Synopsis edited by Dr Paul Schaefer, Toledo, Ohio. Posted on Global Family Doctor 16 August 2011

Pearls are an independent product of the Cochrane primary care group and are meant for educational use and not to guide clinical care.