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Launching a salt substitute to reduce blood pressure at the population level: a cluster randomized stepped wedge trial in Peru

Antonio Bernabe-Ortiz12, Francisco Diez-Canseco1, Robert H Gilman34, María K Cárdenas1, Katherine A Sacksteder3 and J Jaime Miranda15*

Author Affiliations

1 CRONICAS Center of Excellence in Chronic Diseases, Universidad Peruana Cayetano Heredia, Av. Armendariz 497, Miraflores, Lima 18, Peru

2 School of Public Health and Administration, Universidad Peruana Cayetano Heredia, Av. Honorio Delgado 430, Ingenieria, Lima 31, Peru

3 Department of International Health, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, 615 N Wolfe Street, Baltimore, MD, USA

4 Área de Investigación y Desarrollo, Asociación Benéfica PRISMA, Carlos Gonzales 251, Maranga, Lima 32, Peru

5 Department of Medicine, School of Medicine, Universidad Peruana Cayetano Heredia, Av. Honorio Delgado 430, Ingenieria, Lima 31, Peru

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Trials 2014, 15:93  doi:10.1186/1745-6215-15-93

Published: 25 March 2014



Controlling hypertension rates and maintaining normal blood pressure, particularly in resource-constrained settings, represent ongoing challenges of effective and affordable implementation in health care. One of the strategies being largely advocated to improve high blood pressure calls for salt reduction strategies. This study aims to estimate the impact of a population-level intervention based on sodium reduction and potassium increase – in practice, introducing a low-sodium, high-potassium salt substitute – on adult blood pressure levels.


The proposed implementation research study includes two components: Phase 1, an exploratory component, and Phase 2, an intervention component. The exploratory component involves a triangle taste test and a formative research study designed to gain an understanding of the best implementation methods. Phase 2 involves a pragmatic stepped wedge trial design where the intervention will be progressively implemented in several clusters starting the intervention randomly at different times. In addition, we will evaluate the implementation strategy using a cost-effectiveness analysis.


This is the first project in a Latin-American setting to implement a salt substitution intervention at the population level to tackle high blood pressure. Data generated and lessons learnt from this study will provide a strong platform to address potential interventions applicable to other similar low- and middle-income settings.

Trial registration

This study is registered in NCT01960972.

Blood pressure; Hypertension; Operations research; Peru; Potassium chloride; Sodium-restricted diet; Trial