NCT01429246

Brief Summary

The study was a single-blind randomized controlled trial conducted between February and August 2009 in two townships (Yangbajing and Gongtang) of Dangxiong County, an area at 4300 meters altitude in Tibet. A brief baseline survey and assessment for eligibility was performed before randomization. A total of 282 residents with known hypertension (systolic blood pressure ≥ 140mmHg) were recruited and randomly assigned to intervention or control with stratification by gender and baseline blood pressure. The intervention group received 6-month's supply of salt substitute (68% sodium chloride, 22% potassium chloride and 10% magnesium sulfate heptahydrate) and the control group 6-month's supply of regular salt (100% sodium chloride). After 3-month's intervention, the ones with a blood pressure above 140 mmHg / 90 mmHg will be given low-dose diuretic for further anti-hypertensive therapy. The study hypothesis is that salt-substitute will greatly reduce blood pressure in treated patients when compared to controls. Blood pressure levels were measured at baseline and followed up by trained observers using an automated sphygmomanometer and brief survey on level of compliance, amount of salt consumed, and reasons for non-compliance.

Trial Health

87
On Track

Trial Health Score

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

Enrollment
282

participants targeted

Target at P50-P75 for not_applicable hypertension

Timeline
Completed

Started Feb 2009

Shorter than P25 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
6 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

August 1, 2009

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

August 1, 2009

Completed
2.1 years until next milestone

First Submitted

Initial submission to the registry

August 31, 2011

Completed
7 days until next milestone

First Posted

Study publicly available on registry

September 7, 2011

Completed
Last Updated

July 29, 2016

Status Verified

September 1, 2011

Enrollment Period

6 months

First QC Date

August 31, 2011

Last Update Submit

July 27, 2016

Conditions

Hypertension

Keywords

HypertensionDiet TherapySodium Chloride, DietaryTibetAged

Outcome Measures

Primary Outcomes (1)

  • Change in Baseline Mean Systolic Blood Pressure (mmHg) at 6 months

    3 Serial in Right Arm with Seated Patients with at least 1 minute between measurements using Omron 751 Automated Cuff.

    (Baseline compared to 6 months after start of intervention)

Secondary Outcomes (2)

  • Percent of patients having blood pressure under control (<140/90 mmHg)

    Baseline, and post start of intervention at 3 months and 6 months

  • Change in Baseline Mean Systolic Blood Pressure (mmHg) at 3 months.

    (Baseline compared to 3 months after start of intervention)

Study Arms (2)

Normal Salt

ACTIVE COMPARATOR

100% Sodium Chloride

Dietary Supplement: Regular Salt

Salt Substitute

EXPERIMENTAL

65% Sodium Chloride, 25% Potassium Chloride, 10% Magnesium Sulphate)

Dietary Supplement: Salt Substitute

Interventions

Regular SaltDIETARY_SUPPLEMENT

Estimated Household Individual Consumption of 30 grams per day

Normal Salt
Salt SubstituteDIETARY_SUPPLEMENT

Estimated 30 grams per day per household member

Salt Substitute

Eligibility Criteria

Age40 Years+
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Age 40 years or older
  • Resident of Yangbajing Township and Gongtang Village in Tibetan Autonomous Region, People's Republic of China
  • Mean Systolic Hypertension (≥ 140 mmHg)

You may not qualify if:

  • Currently taking any potassium supplements (or lives in household where someone does)
  • Previously diagnosed kidney disease or gout (or lives in a household where someone does) and physician considered he/she cannot take salt substitute.
  • Any person who intended to use salt outside the assigned treatment salt provide in the study

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Dangxiong People's Hospital

Lhasa, Tibet, 850000, China

Location

Related Publications (9)

  • Tian HG, Guo ZY, Hu G, Yu SJ, Sun W, Pietinen P, Nissinen A. Changes in sodium intake and blood pressure in a community-based intervention project in China. J Hum Hypertens. 1995 Dec;9(12):959-68.

    PMID: 8746640BACKGROUND

  • Hooper L, Bartlett C, Davey SG, Ebrahim S. Advice to reduce dietary salt for prevention of cardiovascular disease. Cochrane Database Syst Rev. 2004;2004(1):CD003656. doi: 10.1002/14651858.CD003656.pub2.

    PMID: 14974027BACKGROUND

  • He FJ, MacGregor GA. Effect of longer-term modest salt reduction on blood pressure. Cochrane Database Syst Rev. 2004;(3):CD004937. doi: 10.1002/14651858.CD004937.

    PMID: 15266549BACKGROUND

  • China Salt Substitute Study Collaborative Group. Salt substitution: a low-cost strategy for blood pressure control among rural Chinese. A randomized, controlled trial. J Hypertens. 2007 Oct;25(10):2011-8. doi: 10.1097/HJH.0b013e3282b9714b.

    PMID: 17885542BACKGROUND

  • Zhou X, Liu JX, Shi R, Yang N, Song DL, Pang W, Li YM. Compound ion salt, a novel low-sodium salt substitute: from animal study to community-based population trial. Am J Hypertens. 2009 Sep;22(9):934-42. doi: 10.1038/ajh.2009.135. Epub 2009 Aug 6.

    PMID: 19661926BACKGROUND

  • He FJ, MacGregor GA. Can a low-sodium, high-potassium salt substitute reduce blood pressure in rural Chinese people? Nat Clin Pract Cardiovasc Med. 2008 Apr;5(4):186-7. doi: 10.1038/ncpcardio1122. Epub 2008 Jan 29. No abstract available.

    PMID: 18227813BACKGROUND

  • Hu J, Jiang X, Li N, Yu X, Perkovic V, Chen B, Zhao L, Neal B, Wu Y. Effects of salt substitute on pulse wave analysis among individuals at high cardiovascular risk in rural China: a randomized controlled trial. Hypertens Res. 2009 Apr;32(4):282-8. doi: 10.1038/hr.2009.7. Epub 2009 Feb 27.

    PMID: 19262499BACKGROUND

  • Li N, Prescott J, Wu Y, Barzi F, Yu X, Zhao L, Neal B; China Salt Substitute Study Collaborative Group. The effects of a reduced-sodium, high-potassium salt substitute on food taste and acceptability in rural northern China. Br J Nutr. 2009 Apr;101(7):1088-93. doi: 10.1017/S0007114508042360. Epub 2008 Aug 19.

    PMID: 18710605BACKGROUND

  • Zhao X, Yin X, Li X, Yan LL, Lam CT, Li S, He F, Xie W, Sang B, Luobu G, Ke L, Wu Y. Using a low-sodium, high-potassium salt substitute to reduce blood pressure among Tibetans with high blood pressure: a patient-blinded randomized controlled trial. PLoS One. 2014 Oct 22;9(10):e110131. doi: 10.1371/journal.pone.0110131. eCollection 2014.

    PMID: 25338053DERIVED

MeSH Terms

Conditions

Hypertension

Condition Hierarchy (Ancestors)

Vascular DiseasesCardiovascular Diseases

Study Officials

  • Yangfeng Wu, PhD

    The George Institute, China (Beijing, CN)

    STUDY DIRECTOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
SINGLE
Who Masked
PARTICIPANT
Purpose
TREATMENT
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

August 31, 2011

First Posted

September 7, 2011

Study Start

February 1, 2009

Primary Completion

August 1, 2009

Study Completion

August 1, 2009

Last Updated

July 29, 2016

Record last verified: 2011-09

Locations

CN(1)