Salt Reduction on Blood Pressure and Cardiovascular Organ Damage

June 8, 2015 updated by: St George's, University of London

Effects of Modest Salt Reduction on Blood Pressure and Markers of Target Organ Damage in Patients With Untreated Essential Hypertension or Prehypertension

The purpose of this study is to determine the effect of a modest reduction in salt intake on blood pressure in white, black and Asian individuals with hypertension or prehypertension, and also to determine whether a modest reduction in salt intake has beneficial effects on the surrogate markers of target organ damage in cardiovascular disease.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

The average salt intake for adults in the UK is approximately 10-12 g/day. The current recommendations are to reduce salt intake to 5-6 g/day or less. Many randomised trials have shown that this reduction in salt intake has a significant effect on blood pressure, however, most previous trials were carried out in white individuals, fewer in blacks, and none in Asians.

Increasing evidence from epidemiological studies in humans and experimental studies in animals suggest that that our current high salt intake may have other harmful effects on cardiovascular health e.g. a direct effect on stroke, left ventricular hypertrophy, progression of renal disease and proteinuria independent of and additive to salt's effect on blood pressure. However, no well-controlled trials have studied whether a modest reduction in salt intake has beneficial effects on the surrogate markers of target organ damage in cardiovascular disease.

We propose to carry out a double-blind randomised trial to study the effects of a modest reduction in salt intake, as currently recommended, on blood pressure and target organ damage assessed by the measurements of 24 hour urinary albumin excretion, left ventricular mass, left ventricular diastolic function, pulse wave velocity and capillary density, in white, black and Asian individuals with hypertension or prehypertension.

Comparisons: Usual salt intake compared to reduced salt intake.

Study Type

Interventional

Enrollment (Anticipated)

210

Phase

  • Phase 3

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United Kingdom
      • London, United Kingdom, SW17 0RE
        • St. George's University of London,

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 75 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Patients with untreated essential hypertension or prehypertension (sitting systolic blood pressure between 120 and 170 mmHg and/or sitting diastolic blood pressure between 80 and 105 mmHg)
  • Age 18 - 75 years.

Exclusion Criteria:

  • Individuals younger than 18 or older than 75 years
  • Individuals with severe hypertension i.e. blood pressure > 170/105 mmHg
  • Individuals with any secondary cause of hypertension
  • Individuals with impaired renal function with plasma creatinine greater than 150 umol/L
  • Individuals with diabetes mellitus
  • Individuals with malignancy or liver disease
  • Individuals with ischaemic heart disease or heart failure
  • Females who are pregnant or breast feeding or on the oral contraceptive pill.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: Double

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Blood pressure and markers of target organ damage at 6 weeks of usual salt intake vs those at 6 weeks of reduced salt intake.

Secondary Outcome Measures

Outcome Measure
Comparisons among different ethnic groups in the changes in blood pressure and markers of target organ damage from week 6 of usual salt intake to week 6 of reduced salt intake.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

St George's, University of London

Investigators

  • Principal Investigator: Graham A MacGregor, MD, St George's, University of London

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

April 1, 2004

Study Completion (Actual)

December 1, 2007

Study Registration Dates

First Submitted

September 8, 2005

First Submitted That Met QC Criteria

September 8, 2005

First Posted (Estimate)

September 9, 2005

Study Record Updates

Last Update Posted (Estimate)

June 9, 2015

Last Update Submitted That Met QC Criteria

June 8, 2015

Last Verified

September 1, 2006

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • CH/der/03.0214
  • N02034

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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