HeartPhone Cancer Survivors Trial 2019

Study Overview
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Brief Summary
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This is a behavioral study that will examine changes in physical activity and vascular health in response to a digital tool (app) that will appear on participant's lock screen of their Android phone. Participants will be asked to use this app for 3 months and to wear a Fitbit device continuously throughout the study. Participants will be asked to complete questionnaires, participate in fitness testing and measures of cardiovascular health at 3 months and 6 months after baseline assessments. The hypothesis is that exposure to the app will lead to increased physical activity volume and improved microvessel function.

Official Title
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Digital Intervention to Promote Physical Activity and Improve Cardiovascular Health Among Cancer Survivors

Conditions
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Breast Cancer, Leukemia, Lymphoma

Intervention / Treatment
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* Behavioral: HeartPhone app
* Drug: Acetylcholine
* Drug: Sodium Nitroprusside
* Drug: L-Arginine, N2-((4-Methylphenyl)Sulfonyl)-, Methyl Ester


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18-65 years Diagnosis of breast cancer, leukemia, or lymphoma <15 yrs Completed chemotherapy with cardiotoxic anthracycline-based agents 1+ year ago English-proficiency Own & use smartphone with Android operating system Main Study and Ancillary Study Exclusion Criteria: Currently receiving curative treatment for cancer 90+ min/week moderate (or greater) intensity PA Any medical contraindications on the Physical Activity Readiness Questionnaire Require an assistive device for mobility or has any other condition that may limit or prevent participation in moderate-intensity physical activity Current smoker Pregnant or planning to become pregnant in the next 6 mos/breastfeeding Allergy to test substances Allergy to latex Ancillary Study: Taking metformin Current medications that could conceivably alter the cardiovascular or thermoregulatory control or responses (e.g. beta blockers, calcium channel blockers, angiotensin receptor blockers)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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
Intervention Model: Single Group Assignment
Interventional Model Description: Single-group pre-post change
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: HeartPhone Intervention<br>Participants install the HeartPhone app on their smartphone. This app presents an image on a splash screen every time they activate their device. The image is randomly drawn from an image bank in the app. Repeated exposure to the image is designed to condition a more favorable automatic affective evaluation of physical activity and lead to increased physical activity. | Behavioral: HeartPhone app<br>* Evaluative conditioning (temporally distributed micro-doses presented upon activation of smartphone screen)<br>Drug: Acetylcholine<br>* Endothelium-dependent vasodilation is tested with the localized delivery of the neurotransmitter<br>Drug: Sodium Nitroprusside<br>* Endothelium-independent vasodilation is tested with the localized delivery of the nitric oxide donor<br>Drug: L-Arginine, N2-((4-Methylphenyl)Sulfonyl)-, Methyl Ester<br>* This nitric oxide inhibitor is continuously given during the localized delivery of the endothelium-dependent agonist acetycholine.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Physical activity volume | Daily step counts over 1-week from Fitbit device | 3 month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Microvessel function | Skin blood flow during perfusion of endothelium-dependent and independent agonists | 3 month |