LowSalt4Life: A Mobile Application to Reduce Sodium Intake And Blood Pressure

Study Overview
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Brief Summary
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This research is being done to learn if a smartphone app with and without a just in time adaptive intervention (JITAI) can help patients with hypertension manage their sodium intake and improve their blood pressure.

Detailed Description
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The primary and secondary outcomes will be determined in months 1 & 2. Participants will continue for another 4 months and during that time data for exploratory measures will be collected. During the first 2 months of the study, a micro-randomized trial (MRT) will be performed within the App+JITAI group (N=200). This MRT is designed to learn which push notification messages effectively prompt the user to interact with the appropriate content within the mobile application.

Official Title
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A Just-In-Time Adaptive Mobile Application Intervention To Reduce Sodium Intake And Blood Pressure In Hypertensive Patients: LowSalt4Life

Conditions
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Hypertension, Blood Pressure

Intervention / Treatment
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* Behavioral: LowSalt4Life Application
* Behavioral: Just-In-time Adaptive Intervention (JITAI)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosed with essential hypertension (HTN) by a medical provider and are on stable doses of antihypertensive therapy for at least three months prior to enrollment as documented in the electronic health record (EHR) and confirmed by participant self-report. A smartphone with a compatible Apple or Android operating system installed and able to download and use LowSalt4Life app including accepting all permissions and willing to allow the mobile applications to send push notifications A valid email address Fluent in spoken and written English Exclusion Criteria: Unstable symptoms or markedly elevated blood pressure (BP) at enrollment (defined as systolic BP>180 mmHg, diastolic BP>120 mmHg) Contraindication to a sodium restriction diet An estimated sodium intake less than 1,500mg per day Known secondary causes of HTN (e.g., adrenal insufficiency, pheochromocytoma) Estimated glomerular filtration rate (EGFR) <30 or end-stage renal disease on dialysis Heart failure Inability to use Withings devices (blood pressure cuff and scale) due to equipment limitations or contraindications Currently pregnant or intent to become pregnant during the study period

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: LowSalt4Life<br> | Behavioral: LowSalt4Life Application<br>* LowSalt4Life is a dietary sodium intervention mobile application that promotes lower sodium intake.<br>|
| Experimental: LowSalt4Life + just-in-time adaptive intervention (JITAI)<br> | Behavioral: LowSalt4Life Application<br>* LowSalt4Life is a dietary sodium intervention mobile application that promotes lower sodium intake.<br>Behavioral: Just-In-time Adaptive Intervention (JITAI)<br>* LowSalt4Life is a dietary sodium application with a just-in-time adaptive intervention (JITAI) component enabled.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in systolic blood pressure (SBP) | SBP measured by a wireless home blood pressure monitor | Baseline, 2 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in weight over 2 months | Weight measured using wireless scale | Baseline, 2 months | 
| Change in estimated sodium intake | As measured by the Block 2014 Food Frequency Questionnaire | Baseline, 2 months | 
| Change in dietary nutrient intake | As measured by the Block 2014 Food Frequency Questionnaire | Baseline, 2 months | 
| Changes in blood pressure (BP) medications | As measured by the electronic health record | Baseline, 2 months | 
| Percent of participants at a goal blood pressure (BP) | Goal BPs are based on the American Heart Association blood pressure guidelines. | 2 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Dietary sodium