Launching a Salt Substitute to Reduce Blood Pressure at the Population Level in Peru

Sponsor

Universidad Peruana Cayetano Heredia (Other)

Overall Status

Completed

CT.gov ID

NCT01960972

Collaborator

Johns Hopkins University (Other)

2,376

Enrollment

Location

Arm

Actual Duration (Months)

64.2

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

This protocol aims to implement, using a stepped wedge trial design, a population-level intervention to replace high-sodium salt for a salt substitute (low-sodium, high-potassium salt) to reduce blood pressure levels among adults aged 18 years and over of the semi-urban area of Tumbes.

We hypothesize that participants aged 18 years and over from villages receiving a salt substitute will have lower blood pressure compared to control villages.

Condition or Disease	Intervention/Treatment	Phase
Blood Pressure Hypertension	Other: Salt substitute	N/A

Detailed Description

Several randomized clinical trials and meta-analysis have reported that reduction of sodium intake decreases blood pressure. Also, the increase of potassium ingestion in minimal doses has been found in systematic reviews to produce a small reduction in blood pressure levels.

The proposed intervention is a community-wide mass-strategy in which direct delivery of a salt substitute to households is accompanied by wide social marketing campaigns, both before and during the intervention period. With this experimental stepped wedge trial design, we will estimate the impact of a reduced-sodium salt substitution program on blood pressure at the population level.

We propose the following specific aims:

Specific Aim 1: To implement and assess the impact of an intervention using a salt substitute on blood pressure at the population level using a stepped wedge trial design.

Specific Aim 2: To determine costs and efficacy of this implementation strategy using cost-effectiveness analysis.

Study Design

Study Type:

Interventional

Actual Enrollment :

2376 participants

Allocation:

N/A

Intervention Model:

Single Group Assignment

Masking:

None (Open Label)

Primary Purpose:

Prevention

Official Title:

Launching a Salt Substitute to Reduce Blood Pressure at the Population Level - Peru

Actual Study Start Date :

Mar 1, 2014

Actual Primary Completion Date :

Mar 1, 2017

Actual Study Completion Date :

Apr 1, 2017

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Salt substitute As described by Brown, in a stepped wedge design, an intervention is rolled-out sequentially to the trial participants (either as individuals or clusters of individuals) over a number of time periods. The order in which the different individuals or clusters receive the intervention is determined at random and, by the end of the random allocation, all individuals or groups will have received the intervention. Stepped wedge designs incorporate data collection at each point where a new group (step) receives the intervention. Thus, the salt substitute will be implemented in each cluster (village) in a randomized fashion. Not arms are needed since the 6 randomly-selected villages will be implemented in some moment of the protocol.	Other: Salt substitute A salt substitute using 25% of potassium chloride and 75% of sodium chloride will be implemented in each of the villages.

Arm

Intervention/Treatment

Experimental: Salt substitute

As described by Brown, in a stepped wedge design, an intervention is rolled-out sequentially to the trial participants (either as individuals or clusters of individuals) over a number of time periods. The order in which the different individuals or clusters receive the intervention is determined at random and, by the end of the random allocation, all individuals or groups will have received the intervention. Stepped wedge designs incorporate data collection at each point where a new group (step) receives the intervention. Thus, the salt substitute will be implemented in each cluster (village) in a randomized fashion. Not arms are needed since the 6 randomly-selected villages will be implemented in some moment of the protocol.

Other: Salt substitute

A salt substitute using 25% of potassium chloride and 75% of sodium chloride will be implemented in each of the villages.

Outcome Measures

Primary Outcome Measures

Systolic/diastolic blood pressure (mmHg) [Three years]
We will assess changes in systolic and diastolic blood pressure over time. Periodic assessments will be carried out to obtain clinical measurements. Every five months, a new evaluation will be performed in all participant villages (intervention and control). Systolic and diastolic blood pressure will be measured in triplicate using standard procedures and automated and validated devices. These periodic assessments will be taken at each household to guarantee contact with each family member enrolled in this study.

Secondary Outcome Measures

Progression to hypertension [Three years]
Using data of systolic and diastolic blood pressure, we will estimate progression towards hypertension among participants in intervened and control villages.

Other Outcome Measures

Cost-effectiveness analysis [Three years]

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years and Older

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Yes

Inclusion Criteria:

Males or females aged 18 years and over from the randomly selected villages.
Capable of understanding study procedures and providing informed consent.
Full-time resident in the area.

Exclusion Criteria:

Self-reported history of chronic kidney disease or heart disease.
Refusal to participate.

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Center for Global Health (Universidad Peruana Cayetano Heredia)	Tumbes		Peru

Sponsors and Collaborators

Universidad Peruana Cayetano Heredia
Johns Hopkins University

Investigators

Principal Investigator: Jaime Miranda, MD, PhD, Universidad Peruana Cayetano Heredia
Principal Investigator: Robert H Gilman, MD, Johns Hopkins Bloomberg School of Public Health
Study Director: Antonio Bernabe-Ortiz, MD, MPH, Universidad Peruana Cayetano Heredia