DASH Cloud: Using Digital Health to Improve Adherence to the DASH Diet Among Women at Risk for Cardiovascular Disease
Phase: NA
Conditions: Diet Modification, Hypertension, Women's Health, Cardiovascular Diseases, Digital Health
Sponsor: Duke University

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Protocol Full Title: DASH Cloud: Using digital health to improve adherence to the DASH diet among women 
at risk for cardiovascular disease 
 
Short Title: DASH Cloud 
 
Purpose of the Study 
One-third of women have hypertension (HTN), and the risk of cardiovascular disease (CVD) because of HTN 
is more serious among women than men. Until recently, however, efforts to reduce CVD mortality focused 
primarily on men. The DASH diet is a proven behavioral strategy to reduce blood pressure, however, national 
adherence rates are poor. Using digital health tools may help to improve adoption of the DASH diet. 
Digital health approaches capitalize on the ubiquitous utilization of mobile technologies and have broad 
dissemination potential. There have been few efforts to test a DASH intervention via digital health and none 
directed to women. This proposal will leverage a commercial diet tracking application and our existing 
intervention technology platform to test the feasibility of DASH Cloud, a digital health intervention for women 
with pre-hypertension and hypertension. The primary outcome is DASH diet adherence. 
 
Background and Significance 
Women need better interventions for hypertension self-management. One-third of and pre and 
postmenopausal women have hypertension1 and only half of those women have their blood pressure under 
control. Uncontrolled blood pressure is the strongest predictors of heart disease – the leading cause of death 
among women. This is because heart disease is more serious among women than men. After a heart attack, 
women have lower survival rates and a poorer quality of life. Despite these gender-based differences in 
outcomes, our understanding is limited about how to address the unique issues that women face in managing 
hypertension behaviorally. Developing behavioral interventions specifically for women in the pre- and 
postmenopausal period is critical to alleviating the burden of hypertension and heart disease among women. 
 
Improving diet is vital to managing hypertension. Along with medical management, behavioral 
interventions can play a pivotal role in the management of hypertension. The DASH (Dietary Approaches to 
Stop Hypertension) diet is a nationally recognized dietary treatment for hypertension. DASH emphasizes 
nutrient-rich foods such as fruits and vegetables, whole grains, and low-fat dairy products, and limits sweets 
and sugar-sweetened beverages, as well as foods high in sodium, saturated fat and cholesterol. Two seminal 
randomized controlled feeding trials established the blood pressure-lowering effect of the DASH diet. Many 
subsequent studies and effectiveness trials have validated its effect.8,9.10 The initial DASH trial was a four-site, 
randomized, controlled feeding study led by co-investigator, Dr. Laura Svetkey. Compared to a control diet 
typical of U.S. consumption, DASH produced reductions in systolic and diastolic blood pressure of 5.5 and 3.0 
mmHg respectively (each p<0.001). Blood pressure changes were evident in subgroups of men, women, 
racial/ethnic minorities, whites, and in both hypertensive and normotensive participants.7 DASH was 
particularly effective for those with hypertension (systolic (SBP) and diastolic (DBP) change: -10.7 mmHg and - 
4.7 mmHg, respectively), and among blacks (SBP and DBP change: -6.8mmHg and -3.7 mmHg).11 The follow-
up DASH–Sodium trial, also led by Dr. Svetkey, demonstrated that reducing sodium intake while consuming 
the DASH diet produces larger blood pressure reductions and greater increases in blood pressure control than 
either DASH or sodium reduction alone. 
 
Digital health approaches are promising intervention channels for improving DASH diet adherence. 
Almost all Americans own a mobile phone and 97% of mobile phone owners use text messaging. Digital 
health approaches can capitalize on the ubiquity of mobile technologies and allow us to reach affected 
populations with highly personalized content at low cost. Despite this ubiquity, interventions using text 
messaging for hypertension self-management primarily rely on reminders for tracking and medication 
adherence without diet and physical activity behaviors or feedback. As such, they are less effective. Our work 
has shown that we can provide obesity treatment to a variety of populations, including women, through 

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mobile technologies. Our work is unique because we go beyond simply sending tips or reminders. Rather, our 
interventions prescribe tailored behavior change goals, prompt tracking of these goals via mobile 
technologies and then send immediate tailored feedback. As a result, we have been successful in achieving 
high rates of tracking adherence17,20 I aim to leverage my experience working on digital health intervention 
trials to improve adherence to the DASH diet among women with hypertension. 
 
This study will have several areas of impact. We will establish the feasibility of a novel digital health-based 
approach for disseminating the DASH diet for women, using Nutritionix, a commercially available diet tracking 
app that thousands of Americans are already using. The data from this pilot feasibility trial will set the 
foundation for a larger, fully-powered R01 grant to examine whether DASH Cloud can improve blood pressure 
outcomes among women with hypertension. This proposal will focus on the following specific aims. 
 
Aim 1: To modify existing technology platforms and develop content for the DASH Cloud intervention for 
women with hypertension or pre-hypertension. 
 
Aim 2: To test the feasibility of the DASH Cloud intervention compared to education control among women with 
hypertension or pre-hypertension (n=up to 65) via a 3-month randomized controlled trial. 
• Utilization of intervention components – daily diet tracking rates, and clicks to skills training materials. 
• Change in dietary patterns– 3-month change in DASH diet adherence score (as measured from 24-
hour recalls) 
• Acceptability - patient satisfaction and intention for continued use as measured by surveys. 
 
Aim 3: To evaluate the preliminary efficacy of the DASH Cloud intervention relative to education control on 
blood pressure, weight, and medication adherence at 3 months. 
 
Design and Procedures 
 
Study Design 
We will enroll up to 200 adult women aged 21-70 with pre-hypertension or hypertension in order to qualify up to 
65 to be randomized in a 3-month randomized controlled trial to test the initial feasibility of DASH Cloud, a 
digital health intervention for women with HTN. More details are described below. 
 
Selection of Subjects 
Setting:  We will recruit community participants from the Durham, NC area. Using designated space at the 
Sarah W. Stedman Center for Nutrition and Metabolism at Duke and Duke Digital Health, participants will 
complete baseline and follow-up visits where they will complete physiological and survey-based data 
collection.  
 
Sample: We will randomize participants to either the DASH Cloud intervention or to DASH Light education 
control and follow up at 3 months.  
 
Inclusion/Exclusion: 
Inclusion: ages 21-70 years; BMI >18.5 kg/m2; on self-reported use antihypertensive medication or self-
reported systolic blood pressure 120-159 mmHg and/or diastolic blood pressure of 80-99; current use of a 
smartphone with an updated operating system, data plan, willingness to be texted daily or weekly; an active 
email account; spoken and written English fluency. 
 
Exclusion: CVD event in prior 6 months; active malignancy; active psychosis or recent psychiatric 
institutionalization; current pregnancy or lactation; current participation in a similar trial. 
 
Subject Recruitment and Compensation 

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We will recruit participants using a multi-pronged strategy: 1) we will distribute flyers at local gyms, community 
centers, grocery stores, and health and wellness stores; 2) we will collaborate with Duke Early Phase Clinical 
Research (formerly DCRU) and the Duke Primary Care Research Consortium (PCRC) to request that they 
query their database for subjects who fit the inclusion/exclusion criteria and email them information about the 
study, including a link to the study websites (dashcloud.org or dashcloudstudy.com). These URLs do not 
contain study information, rather they just redirect participants to the REDCap screening survey; 3) we will use 
social media (Twitter and Facebook) to advertise the study and direct interested subjects to the study web site, 
and; 4) we will email community organizations, including local health departments and churches, information 
about the study, including a link to the study web site. 5) We will use the contact list for participants who were 
ineligible for Study D0822 Comparing Self-Monitoring Strategies for Weight Loss (Campus IRB) that 
acknowledged they were interested in being contacted for other studies. 6) We will use ResearchMatch.org to 
connect with potentially eligible subjects. We have used these methods successfully in many of our team’s 
previous studies.  
 
Those who respond to study marketing will undergo preliminary eligibility screening via a REDCap eligibility 
survey linked from our study website. Those who are deemed potentially eligible will be given a link to a video 
outlining study participation (https://www.youtube.com/watch?v=4UW23zTuaZQ). Interested participant will 
then be asked to complete an online consent form. After the consent form is signed, participants will be sent a 
REDCap link to fill out questionnaires asking about sociodemographic and behavioral characteristics. 
Participants will be asked to complete 2 dietary recalls on the ASA-24 website. Study staff will send 
instructions to the participant to download and setup the Nutritionix app before their initial baseline visit. If 
needed, participants will be provided assistance from study staff to download and setup the app at the initial 
baseline visit. They will then be asked to take part in an initial baseline study visit at the Sarah W. Stedman 
Center for Nutrition and Metabolism at Duke or Duke Digital Health. At the first visit, the study staff will 
complete physiological data collection to confirm final eligibility. Participants with a blood pressure outside the 
upper range of eligibility will be told they can no longer participate. At this visit, study staff will provide 
instructions for how to use the app. We will ask women to track their diet for one week. After one week, if they 
successfully tracked at least 4 of 7 days, they will be asked to attend a 2nd baseline visit where they will be 
randomized and enrolled in the study. At this visit, participants will also receive a 30-minute in-person, 
individual orientation to the DASH diet to learn what is required in each study group. Participants who do not 
qualify based on non-inclusion, exclusion, or non-consent will be tabulated, noting the reason for non-
participation.  All subjects who attend the two baseline visits will receive a Duke ClinCard with a value of $25. 
Enrolled subjects will receive another $25 via their ClinCard after attending the 3-month follow up visit. 
 
Consent Process 
 
INFORMED CONSENT 
The informed consent process for this study involves several components.   
-       First, participants will hear about the study from one of the previously-described recruitment 
methods.   
-       Next, participants will complete an online screening questionnaire. If preliminarily eligible, 
participants will then be shown a video that provides an overview of study participation and risks. 
Once they watch the video (script and link uploaded into full protocol section), participants will 
review the online consent form via REDCap. If they have any questions about consent before 
signing, participants can ask for a followup in the REDCap survey.  The study team will receive a 
prompt via REDCap and follow-up via phone with the participant. If there are no questions and/or 

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after the participant has had their questions answered by research staff, participants will provide a 
signature in the online consent. 
-       Once they sign the online consent, a pdf version of the consent is sent to the participant via secure 
email. Each participant’s signed informed consent form will also be kept on file by the investigators for 
possible inspection by regulatory authorities. 
The mobile health intervention involves a potential risk of loss of confidentiality of the subject’s mobile device 
number and the self-reported lifestyle habits regarding nutrition only.  The data collection stored on REDCap 
involves a minimal risk of loss of protected health information.  We will use the language in the consent form to 
inform patients of these risks.   
 
 
Subject’s Capacity to give legally effective consent:  see above, “consent” 
 
Study interventions:  
Participants will download and install the Nutritionix application (“app”) onto their smartphone and study staff 
will setup the study-specific account to send data to Duke’s software system called Prompt. Participants will be 
instructed to input their dietary intake daily for three months using the Nutritionix app. DASH Cloud will access 
participant’s dietary intake data through the Nutritionix application programing interface (API) for three months. 
Participants’ data will automatically be uploaded from the Nutritionix app via the API that links the device with 
DASH Cloud. This secure system will store participant ID, email and password credentials for logging into 
Nutritionix, phone number, and all tracking data. DASH Cloud will run an algorithm and send a daily or weekly 
feedback text message with a score reflecting DASH adherence for the prior days or week’s food consumption 
using a previously validated scoring system.  
 
Each week, we will also deliver a link via text to a video that displays content about a topic related to the DASH 
diet (e.g., how to get more potassium and less sodium - 
https://www.youtube.com/watch?v=gUbKisHsC6k&feature=youtu.be).  
 
Control participants will be asked to use the Nutritionix app daily and receive publicly available written 
materials on the DASH diet at the baseline visit. After baseline, they will receive no other feedback via text 
message. Each intervention component is described in more detail 
below. 
 
Tailored feedback texts. With DASH Cloud, as in several of our 
center’s previous studies, we will provide tailored feedback about a 
participant’s DASH adherence via fully automated daily or weekly text 
messages (see separate document with sample text messages). These 
feedback messages will describe both an individual’s absolute 
performance and change over time (see Figure 2 for example). As 
shown, we also include theory-driven tailored content that reinforces 
successes, offers motivational strategies, and offers short behavior 
change tips. We will take this content from the extensive feedback library 
(insert link to box here) used in our other studies (PI Bennett: Shape - 
2628 (Campus IRB); Track - B0033 (Campus (IRB)). The library contains 
verbiage options with major categories (e.g., user is improving, stable, 
declining) and subcategories (e.g., motivational messages, validation, 
reinforcement, challenges). We will recommend that individuals self-
monitor their dietary intake daily and we will prompt users with 
engagement messages when they don’t track. In our past several trials, 
we have become adept at developing messages that are appropriate for 
the constraints of text messaging.  

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Behavioral skills training. We will include behavioral skills training content in video format created by our 
study staff, drawn from materials about DASH available from the National Institute of Health, National Institute 
of Lung, Blood and Health (https://catalog.nhlbi.nih.gov/pubstatic//06-
5834/YourGuideLowBloodPressureBrief.pdf).  The skills training lessons cover a wide range of topics (food 
labels, recipe modification, reducing fat, sodium, etc.). We will send links to this content in weekly texts. A 
sample video can be found here: http://bit.ly/2q0Hvxd. 
 
 
Measures 
Engagement: The primary feasibility outcome is utilization of intervention components at 3 months. 
1) Diet tracking: proportion of participants completing daily dietary self-monitoring 
2) Review of skills training: number of clicks to skills training via video tracking software. 
 
DASH adherence: Dietary intake data will be collected using NCI’s Automated Self-Administered 24-hour 
Recall tool (https://asa24.nci.nih.gov/). Participants will be prompted via email by study staff to complete the 
ASA-24. We will collect 2 dietary recalls at baseline and 3 months. To determine DASH adherence, we will use 
a previously determined index based on 11 food groups (e.g., fruits) and nutrients (e.g., sodium). We have 
experience using the ASA-24 in a previous trial with much success. 
 
Patient satisfaction: We will use measures that we have delivered successfully in prior studies. 
 
Blood pressure: Blood pressure will be measured at baseline and 3 months in the upper arm in triplicate at 1-
minute intervals. Measurements will be obtained by trained study staff using the validated Omron HEM-907XL 
blood pressure monitor. 
 
Sociodemographics: We will collect self-reported age, race/ethnicity, health insurance, income, employment 
status, education, current health status, household size, and marital status at baseline only. 
 
Risk/Benefit Analysis 
The primary risk to the subject is loss of confidentiality.  The mobile technology carries a higher risk of this than 
the other stored data due to the nature of mobile technology and the servers used to deliver the intervention.  
We will follow data security plans used in our previous and current studies, which were developed with the 
guidance of Duke Office of Information Security.  The details are explained below in the data and safety 
monitoring section.   
 
Potential benefits for study participants include improved blood pressure and consequent reduction in 
cardiovascular risk. An additional benefit for some participants may be personal satisfaction in being part of a 
study that may have major public health implications for the community. No benefit from participation can be 
guaranteed. Potential benefits to others include the possibility that this research will help researchers evaluate 
the feasibility and efficacy of the DASH Cloud system in promoting DASH diet adherence. The minimal health 
risks to participants listed above are offset by the potential benefits to them and to society. 
 
Cost to the Subject 
No costs are incurred by the subject, unless the subject is charged for receiving text messages or data usage 
for watching videos.  This is very uncommon, and if it occurs, the cost is typically less than 3 cents per text 
received. 
 
Data Analyses and Statistical Considerations 
We will perform descriptive analyses to determine engagement and feasibility. Linear mixed modeling will be 
used to test for across group differences in DASH adherence and other secondary outcomes. Our model will 

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include group, time, and a group by time interaction, and will be fitted with a full maximum likelihood method 
using all data. As this is a feasibility study, we have estimated sample size from our previous text messaging 
trial where we saw strong engagement; 50% texted daily and 85% texted at least 2 days/week.  
 
Data and Safety Monitoring 
Study records that identify patients will be kept confidential as required by law. All data will be marked with a 
unique code number for storage at Duke University Health System in accordance with Duke’s Institutional 
Review Board's guidelines and policies. All data collection will occur in private settings where patient survey 
responses cannot be seen or heard by others. Patients can refuse to answer any of the questions or stop 
participation in this study at any time.  
 
Mobile technology: Information collected by Nutritionix mobile app is subject to the terms of use.  Many apps 
make claims that they are secure, compliant with federal privacy regulations, and used and tested by other 
academic centers. However, any mobile app that is downloaded carries potential security risks, and Duke 
cannot guarantee that these mobile apps are free of risk.  Some apps may be able to perform hidden functions 
or may have security flaws that allow unauthorized access to information. We are unable to fully tell 
participants what information these mobile apps can access or change on their phone or what information from 
their phone may be stored outside of Duke. Participants will be encouraged to limit personal identifiers entered 
into mobile applications only to those that they wish to voluntarily share with others. 
 
The DASH Cloud environment is processed and stored on Heroku, an application server platform. This 
platform will support the following DASH Cloud services: the DASH Cloud database, text message (SMS) 
communications via Twilio, software logging, and file serving. The DASH Cloud environment sends and 
receives data to/from Twilio and stores data on Amazon S3. We will collect names, phone number, study ID, 
and nutrition information from Nutritionix in this database. DASH Cloud will receive nutrition information via the 
Nutritionix API on ten different nutrients (calories, potassium, magnesium, calcium, total fat, saturated fat, 
protein, cholesterol, fiber, and sodium). The data will be automatically analyzed weekly according to algorithms 
we embed. Study staff use a password-protected database to view study ID, name, phone number, and 
nutrition information for each day for each participant. Staff use multifactor authentication to log into the 
database. We will use Twilio to send text messages to participants each week. We will use Heroku to process 
data analysis for the engine. We will use Amazon S3 to store data; data will be encrypted when it is stored. 
These are companies outside of Duke that will have access to participants’ personal information, including 
name, phone number, and self-monitoring data. If these data are further disclosed by them or their business 
partners, it may no longer be covered under the privacy protections. Text messaging does not provide a 
completely secure and confidential means of communication. Participants are made aware of the risks that are 
inherent in using text messaging.  
 
Participants will complete the ASA-24 measure on https://asa24.nci.nih.gov/. Study staff will create an account 
and password credentials for participants. The account information will not include any personal identifiers. NCI 
will not have access to participant information. Study staff will keep a log of ASA-24 accounts matched to study 
information. This will be stored within a secure Duke box and have access restricted to key study personnel. 
Information from the ASA-24 will be downloaded from the NCI website and stored in a secure Duke box folder. 
 
Participants’ safety will be monitored by maintaining ongoing contact with field staff and convening monthly 
meetings between the investigators and project team. The study field staff will be trained and provided with a 
written protocol that instructs them to contact the study coordinator if any reportable AE occurs. The study 
coordinator will follow-up with participants within 48 hours to ensure that the event has been resolved and 
document actions taken.  
 
 
Privacy, Data Storage and Confidentiality 

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Heroku’s configuration obviates the need for physical server protections such as: protections against port 
scans, firewalls, VPN, vulnerability patches, log rotation, and automated database backups and off-site 
database backup storage.  
 
In its place, the protections now in place are: 
  
• 
Multi-factor authentication and strong passwords protect Web, shell, and console access to the 
Heroku dashboard. 
• 
Application servers are inaccessible. These resources are virtualized and cannot be accessed via 
SSH or SFTP. The application itself is accessible only via SSL. 
• 
No database configuration parameters (including host address, database name, password, and 
login) are stored in the application code or in the code repository. This follows the 12-Factor 
Security Protocol. 
• 
All Amazon services are protected via the provider’s IAM and 2FA tools. No identifiable information 
is stored on Amazon. 
• 
Log files are available only through the Heroku dashboard. Log files do not reveal passwords, IP 
addresses, or PII. Identifying information is limited to the participant’s masking study ID. 
• 
SMS activity is protected by strong passwords and 2FA. 
  
Further, logins to Heroku are severely restricted. Currently, only two people have access to all resources: one 
is the developer and the other is program manager. Research staff does not have access to any computing 
resources. The information generated by this study will be kept for seven years after the date of last 
publication. Then it will be destroyed by shredding the paper copies and by securely deleting the computer 
files.  Data management will take place under the supervision of Dr. Steinberg. Our group has developed 
extensive quality assurance procedures, including on-going quality control checks. After data analysis, we plan 
to disseminate the results of the study via journal publications and presentations. We will not collect 
information about illegal activities. Further, we do not expect that participants will reveal information subject to 
reporting because the Research Assistant will be instructed to maintain close adherence to a protocol that 
involves discussing only behavior change efforts related to diet.   
 
Electronic study data storage: A REDCap database will be created and shared with key personnel on this 
study, and used to store information collected at screening and in the “Measures” section above.  Using 
encrypted study computers, a trained research assistant will send links to REDCap surveys to consented 
subjects via email. At the time of analysis and after data cleaning, we will export the data from REDCap into 
secured statistical software as above.  All output analyses will be stored on a secure Duke Box folder created 
for this study and with access restricted to key personnel. 
 
Physical data storage: All hard copies of participant data will be stored in office or lab space at the Duke Global 
Digital Health Science Center at 310 Trent Dr. in a locked office in a locked file cabinet or in the CRC’s office 
space accessed by badge in a locked filing cabinet on the 10th floor of Erwin Square Plaza 2200 W. Main St.