NCT01566084

Brief Summary

The investigators hypothesize that reducing salt in the diet will improve the function of blood vessels in middle aged and older adults with moderately elevated systolic blood pressure, by increasing the amount of BH4 and nitric oxide in your blood vessels and reducing the amount of oxidative stress.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
17

participants targeted

Target at below P25 for not_applicable hypertension

Timeline
Completed

Started Feb 2009

Typical duration for not_applicable hypertension

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

February 1, 2009

Completed
2.9 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

January 1, 2012

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

January 1, 2012

Completed
3 months until next milestone

First Submitted

Initial submission to the registry

March 23, 2012

Completed
6 days until next milestone

First Posted

Study publicly available on registry

March 29, 2012

Completed
2.2 years until next milestone

Results Posted

Study results publicly available

June 20, 2014

Completed
Last Updated

January 7, 2016

Status Verified

December 1, 2015

Enrollment Period

2.9 years

First QC Date

March 23, 2012

Results QC Date

May 20, 2014

Last Update Submit

December 4, 2015

Conditions

Hypertension

Outcome Measures

Primary Outcomes (1)

  • Improved Flow Mediated Dilation

    FMD is analyzed at weeks 5 and 10 or after each condition in this cross-over study design. Subjects are randomly assigned to a low salt or normal salt condition for the first set of 5 weeks and then crossed over to the other condition for the second set of 5 weeks.

    Week 5 (after first condition of low salt or normal salt), Week 10 (after second condition, opposite to first)

Secondary Outcomes (2)

  • Vascular Oxidative Stress

    Immediately following acute infusion of ascorbic acid on Weeks 5 and 10

  • BH4 Bioavailability

    Immediately following acute administration of BH4 on Weeks 5 and 10

Study Arms (2)

Normal sodium

OTHER

Subjects on a 1200 mg sodium diet are given 2300 mg sodium in the form of slow sodium tablets to bring them back up to a normal salt intake. Subjects then cross-over to the low sodium condition in the second half of the study.

Drug: Slow sodium tablets

Low sodium

OTHER

Subjects on a 1200 mg salt diet are given placebo pills in order to maintain them on a low salt diet. Subjects then cross-over to the normal sodium condition in the second half of the study.

Other: placebo

Interventions

Slow sodium tabletsDRUG

The normal salt condition is maintained with 2300 mg / day in the form of slowly released salt (NaCl) tablets.

Normal sodium
placeboOTHER

Placebo tablets are administered to maintain the low sodium condition.

Low sodium

Eligibility Criteria

Age50 Years - 79 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • years of age
  • SBP 130-159 mmHg

You may not qualify if:

  • Have been sick with an infection in the past two weeks
  • Are currently sick or have ongoing health problems such as kidney or CVD
  • Have lost more than 11 lbs. in the last 3 months
  • Are taking any type of antioxidants
  • Smoke or have alcohol problems
  • Have blood glucose levels higher than 126 mg/dL
  • Have resting SBP below or less than 100 mmHg or greater than 159 mmHg
  • Have a resting diastolic blood pressure greater than 99 mmHg
  • Have a BMI greater than 40 kg/m\^2
  • Are presently consuming less than 9 or greater than 18 grams of salt / day
  • Have a baseline FMD of greater than 6%
  • Are taking any of the following types of drugs: blood thinners, anti-seizure medications, ant-inflammatory drugs
  • Participate in any high endurance athletic training
  • Taking Hormone Replacement Therapy
  • Have not been post-menopausal for at least 1 year

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Clinical Translational Research Center

Boulder, Colorado, 80309, United States

Location

Related Links

MeSH Terms

Conditions

Hypertension

Condition Hierarchy (Ancestors)

Vascular DiseasesCardiovascular Diseases

Limitations and Caveats

Due to the complexity, burden, and, in some cases, invasiveness of the study design and procedures, only a limited number of subjects could be studied.

Results Point of Contact

Title
Dr. Kristen Jablonski
Organization
University of Colorado Denver
KRISTEN.NOWAK@UCDENVER.EDU
303-724-4842

Study Officials

  • Kristen L Jablonski, PhD

    University of Colorado, Boulder

    PRINCIPAL INVESTIGATOR

Publication Agreements

PI is Sponsor Employee
No
Restrictive Agreement
No

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
TRIPLE
Who Masked
PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
Purpose
TREATMENT
Intervention Model
CROSSOVER
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
College Professor of Distinction

Study Record Dates

First Submitted

March 23, 2012

First Posted

March 29, 2012

Study Start

February 1, 2009

Primary Completion

January 1, 2012

Study Completion

January 1, 2012

Last Updated

January 7, 2016

Results First Posted

June 20, 2014

Record last verified: 2015-12

Locations

US(1)