A Health Coach-Led Digital Lifestyle Intervention (HEALDI)

A Health Coach-Led Digital Lifestyle Intervention (HEALDI) for the Regression of Diffuse Myocardial Fibrosis: A Randomised Controlled Trial

Aim: To evaluate the effectiveness of an artificial intelligence (AI)-assisted 12-month Health Coach-Led Digital Lifestyle Intervention (HEALDI) versus control on diffuse myocardial fibrosis and ambulatory blood pressure in individuals with hypertensive heart disease (HHD), with secondary outcomes including multi-organ health parameters, health behaviours, social support, psychological health, and health-related quality of life.

Background: The global prevalence of hypertensive heart disease (HHD) has increased approximately 1.5-fold, from 7.82 million cases in 1990 to 12.50 million in 2021, and it is now the second leading cause of heart failure worldwide. In HHD, chronic pressure overload drives fibroblast activation and interstitial collagen deposition, leading to diffuse myocardial fibrosis which is associated with cardiac dysfunction, arrhythmias, impaired coronary flow reserve, and an increased risk of sudden cardiac death and heart failure. Although diffuse myocardial fibrosis is potentially reversible, no approved anti-fibrotic pharmacological therapy currently exists. Furthermore, there is limited evidence evaluating the effectiveness of lifestyle interventions, particularly aerobic exercise, in reversing diffuse myocardial fibrosis.

Design: A parallel, single-blinded two-arm randomised controlled trial.

Method: This study is a randomised controlled trial with repeated measures, recruiting 200 physically inactive individuals with HHD from the community, including participants from Project RESET, a community-based cohort study in Singapore. Participants will be randomly allocated to either the intervention or control group.

Participants in the intervention group will receive the 12-month HEALDI intervention, which includes the HEALDI mobile application, wearable device, and remote health coaching. Participants in the control group will receive a wearable device and a basic mobile application without intervention features, used solely for data collection.

Data will be collected at baseline (upon randomisation) and at 6, 12 and 24 months. A process evaluation will be conducted using intervention engagement data. In addition, semi-structured interviews with participants and health coaches will explore perceptions of the intervention and behaviour change. A within-trial economic evaluation, from both healthcare system and societal perspectives, will be performed to assess cost-effectiveness.

Significance: This study will generate insights into the role of lifestyle modification as a complementary, non-pharmacological strategy alongside pharmacotherapy to halt or slow HHD progression, improving long-term cardiovascular outcomes.

Study Overview

• Status: Not yet recruiting
• Conditions: Myocardial Fibrosis; Hypertension; Hypertensive Disease; Left Ventricle Hypertrophy
• Intervention / Treatment: Other: HEALDI Intervention

Detailed Description

Specific Study Aims

1. To compare the effectiveness of HEALDI on change in diffuse myocardial fibrosis, ambulatory blood pressure, with secondary outcomes including multi-organ clinical parameters (e.g. blood tests, liver and brain imaging) and patient-reported outcomes (e.g. physical activity, dietary practices, perceived stress, sleep quality, medication adherence, social support, psychological health, and health-related quality of life).
2. Examine the cost-effectiveness of HEALDI intervention.
3. Explore the perceptions of the individuals with HHD and health coaches regarding HEALDI.

Hypotheses

It is hypothesised that participants who received the HEALDI intervention, compared to the control group will have:

• Greater regression in diffuse myocardial fibrosis;
• Greater improvement in ambulatory blood pressure;
• Improved multi-organ clinical paramaters;
• Greater adoption and sustained adherence to health behaviours;
• Better quality of life;
• Lower cost to participants and hospitals.

HEALDI Intervention The HEALDI intervention is a 12-month, AI-assisted, health coach-led digital lifestyle intervention comprising a wearable device, HEALDI mobile application, health coach web portal, and administrative web portal. The system functions as an integrated platform to facilitate interaction between participants and health coaches, supporting personalised lifestyle modification.

Participants will access the HEALDI mobile application via their personal smartphones and will be provided with a wearable device that continuously collects activity and physiological data. These data, together with participant-entered health metrics (e.g., blood pressure, medication), will be synchronised to a secure cloud server and made available on the health coach portal to inform coaching sessions, including goal setting and progress review.

Certified health coaches will deliver 30-45-minute remote coaching sessions over 12 months: weekly during the first month, biweekly for the subsequent 5 months, and monthly for the remaining 6 months.

Data Analysis Data will be analysed using IBM SPSS Statistics Version 29.0, with two-tailed p<0.05 indicating statistical significance. Analyses will follow the intention-to-treat principle. Baseline categorical variables will be compared using Chi-squared or Fisher's exact tests, and continuous variables using independent t-tests or Mann-Whitney U tests, depending on normality. Linear mixed models will assess repeated continuous outcomes, and generalized estimating equations (GEE) will be used for ordinal outcomes. Descriptive analyses will summarise utilisation of the mobile app, wearable adherence, and coaching engagement.

Qualitative interviews will be audio-recorded, transcribed, and analysed thematically using Braun and Clarke's six-step framework. Two independent coders will familiarise themselves with the data, generate initial codes and iteratively refine them through discussion.

• Study Type: Interventional
• Enrollment (Estimated): 200
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Wenru Wang, PhD; Phone Number: (65) 66011761; Email: nurww@nus.edu.sg

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Left ventricular hypertrophy on cardiovascular magnetic resonance based on local age and sex specific criteria
• Age 40-70 years old
• Has internet access
• Owns and uses a smartphone daily
• Able to converse and comprehend the English or Chinese language

Exclusion Criteria:

• History of major cardiovascular events (MACE), which is defined as coronary heart disease death, non-fatal myocardial infarction, stroke
• Diagnosed with secondary causes of hypertension (E.g., renal causes - renal artery stenosis, chronic renal failure; endocrine causes- pheochromocytoma, Cushing's syndrome, hyperthyroidism; cardiac causes - coarctation of the aorta)
• Diagnosed with significant coronary artery disease with previous percutaneous intervention or coronary artery bypass surgeries
• Diagnosed with cardiac arrhythmias such as atrial fibrillation and frequent premature ventricular contractions
• Diagnosed with inherited/acquired cardiomyopathies (E.g., hypertrophic cardiomyopathy, dilated cardiomyopathy)
• Diagnosed with infiltrative disease (E.g., cardiac amyloid, cardiac sarcoid)
• Contraindications to Brain and Cardiac Magnetic Resonance or gadolinium contrast (E.g., renal failure- eGFR <30ml/min/m2 or documented contrast allergy; implantable devices such as cardiac pacemakers, brain aneurysms or clips, metal implants (including braces), foreign bodies in the eye; claustrophobia; end organ failure; women who are pregnant or breast-feeding)
• Any pre-existing medical conditions or disabilities that limits their participation in lifestyle interventions (E.g., Dementia)
• Individuals who have achieved the Singapore physical activity guideline of 150 minutes of moderate intensity exercise or 75 minutes of vigorous intensity exercise per week or an equivalent combination per week
• Limited life expectancy of less than 12 months
• Participating in other research projects involving behavioural therapy or changes related to physical activity

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: HEALDI Intervention Group; A 12-month, AI-assisted, health coach-led digital lifestyle intervention where participants will receive a wearable, HEALDI mobile app and remote health coaching sessions.	Other: HEALDI Intervention; Proposed Mobile application features include: educational content on HHD and lifestyle behaviours (e.g., physical activity, nutrition, stress, sleep), AI-driven exercise recommendations (frequency, intensity, duration, and type), reviewed and approved by health coaches prior to delivery, Health logging (e.g., blood pressure, medication), Personalised dashboard displaying wearable and self-reported data, Goal setting and progress tracking (short- and long-term), Behavioural nudges (AI-driven and rule-based), Messaging function to facilitate communication with health coaches. Health coaching session involve personalised goal setting and review.
No Intervention: Control Group; Participants will receive a wearable and basic mobile app without intervention features, used solely for data collection.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Regression of diffuse myocardial fibrosis	Change in indexed interstitial volume assessed by cardiovascular magnetic resonance	Baseline and 12 months upon randomisation

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Blood pressure	Change in the average 24-hour systolic and diastolic blood pressure	Baseline and 12 months upon randomisation
Left ventricular function	Assessed using cardiovascular magnetic resonance	Baseline and 12 months upon randomisation.
Left ventricular mass	Assessed using cardiovascular magnetic resonance for changes from baseline, indexed to body surface area (g/m2).	Baseline and 12 months upon randomisation.
Left ventricular volume	Assessed using cardiovascular magnetic resonance.	Baseline and 12 months upon randomisation.
Diastolic and systolic function	Assessed by echocardiogram	Baseline and 12 months (upon randomisation)
Valvular function	Assessed by echocardiogram	Baseline and 12 months (upon randomisation).
Heart function	Assessed by electrocardiogram	Baseline and 12 months upon randomisation
First occurrence of cardiovascular event	Heart failure, Myocardial Infarction, Strokes and Death	2 years
Markers of liver fat, inflammation and stiffness	Assessed by liver fibroscan	Baseline, 12 months and 24 months upon randomisation
Markers of liver fat, inflammation and stiffness	Assessed by liver magnetic resonance	Baseline and 12 months upon randomisation.
Brain structure	Assessed using brain magnetic resonance to characterise brain microstructure and extracellular space.	Baseline, 12 months and 24 months upon randomisation.
Cognitive function	Cognitive function will be assessed by the Montreal Cognitive Assessment (MoCA), on a 0-30 scoring scale. Thresholds are: Severe cognitive impairment: 0-9 Moderate cognitive impairment: 10-17 Mild cognitive impairment: 18-25 Normal cognitive performance: 26-30	Baseline and 12 months upon randomisation.
Cardiac and inflammatory markers	Cardiac and inflammatory markers, including but not limited to C-reactive Protein and Cardiac Troponins, will be assessed by blood specimen.	Baseline, 12 months and 24 months
Circulating biomarkers of inflammation and fibrosis	Assessed using blood specimen, inclusive of but not limited to, PICP (procollagen type I carboxy-terminal propeptide) and PIINP ( procollagen type III amino-terminal propeptide).	Baseline and 12 months upon randomisation.
Liver function tests	Assessed by blood specimen	Baseline, 12 months and 24 months from randomisation
Lipid profile	Assessed by blood specimen	Baseline, 12 months and 24 months upon randomisation
Renal function markers	Renal function markers, including but not limited to creatinine, will be assessed by blood specimen	Baseline, 12 months and 24 months from randomisation
Glycemic control	Assessed by fasting blood specimen	Baseline, 12 months and 24 months upon randomisation.
Body Mass Index	Change in Body Mass Index (BMI) will be assessed using weight (kilograms) and height (meters) combined to report BMI in kg/m^2.	Baseline, 12 months and 24 months upon randomisation.
Body composition: Body fat	Body fat (% or kg) will be assessed by Bioelectrical Impedance Analysis (BIA) and dual-energy X-ray absorptiometry (DEXA)	Baseline and 12 months upon randomisation.
Body composition: Muscle Mass	Muscle mass (kg) will be assessed by Bioelectrical Impedance Analysis (BIA) and dual-energy X-ray absorptiometry (DEXA).	Baseline and 12 months upon randomisation.
Body composition: Total body water	Total body water (% or Litre) will be assessed by Bioelectrical Impedance Analysis (BIA) and dual-energy X-ray absorptiometry (DEXA).	Baseline and 12 months upon randomisation.
Waist Circumference	Change in waist circumference	Baseline, 12 months and 24 months upon randomisation.
Energy expenditure	Assessed by whole body calorimetry	Baseline and 12 months upon randomisation.
Depressive symptoms	Change in depressive symptoms will be assessed by the Patient Health Questionnaire-9 (PHQ-9), on a scale of 0-27. The following PHQ-9 ranges will be used: Minimal: 0 - 4 Mild: 5 - 9 Moderate: 10 - 14 Moderately severe: 15 - 19 Severe: 20 - 27	Baseline, 6 months, 12 months and 24 months upon enrolment.
Anxiety symptoms	Change in anxiety symptoms will be assessed by the Generalized Anxiety Disorder-7 (GAD-7), on a scale of 0-21. The following ranges will be used: None/minimal: 0 - 4 Mild: 5 - 9 Moderate: 10 - 14 Severe: 15 - 21	Baseline, 6 months, 12 months and 24 months upon enrolment.
Health Behaviour: Physical Activity (Wearable)	Change in physical activity-related wearable data such as accelerometery.	Baseline, 6 months, 12 months and 24 months upon randomisation.
Health Behaviour: Physical Activity (IPAQ-SF)	Change in physical activity behaviour will be assessed by the International Physical Activity Questionnaire-Short Form (IPAQ-SF) to serve as a recall estimate of time spent performing physical activity (moderate or vigorous) and inactivity (sitting). The 7-items include: Vigorous activity (days); Vigorous activity (minutes per day); Moderate activity (days); Moderate activity (minutes per day); Walking (days); Walking (minutes per day); Sitting (days)	Baseline, 6 months, 12 months and 24 months upon randomisation.
Health Behaviour: Physical Activity (MPAM-R)	Change in physical activity behaviour will be assessed by the Motives for Physical Activities Measure-Revised (MPAM-R), consisting of 30-items, each on a 7-point Likert scale (1 = Not at all true for me; 7 = Very true for me), for a total score ranging between 30 - 210. A higher score will indicate higher motivation, while a lower score will indicate lower motivation.	Baseline, 6 months, 12 months and 24 months upon randomisation.
Health Behaviour: Physical Activity (Stage of Change for Physical Activity Questionnaire)	Change in physical activity behaviour will be assessed by the Stage of Change for Physical Activity Questionnaire. The scale consists of 4-items designed to categorise individuals into the five stages of change: pre-contemplation, contemplation, preparation, action, maintenance, based on the Stages of Motivational Readiness for Change Model.	Baseline, 6 months, 12 months and 24 months upon randomisation.
Health Behaviour: Sleep Quality and Duration	Change in Sleep Quality and Duration will be assessed using the Pittsburgh Sleep Quality Index (PSQI) and wearable-derived metrics. The scale consists of 19-items across seven components: (1) sleep duration, (2) sleep disturbance, (3) sleep latency, (4) daytime dysfunction, (5) sleep efficiency, (6) sleep quality, and (7) sleep medication usage. Each component will yield a score from 0 - 3, and will be tallied to yield a score from 0 - 21, with higher scores indicating worse sleep quality. Good sleep quality: 0 - 5 Poor sleep quality: 6 - 21	Baseline, 6 months, 12 months and 24 months upon randomisation.
Health Behaviour: Sleep (Wearable)	Change in sleep-related wearable data	Baseline, 6 months, 12 months and 24 months upon randomisation
Health Behaviour: Perceived Stress	Change in perceived stress will be assessed using the Perceived Stress Scale-10 (PSS-10). The scale consists of 10 items rated on a 5-point Likert scale (0 - 4, 0 = Never; 4 = Very often), totalling a score of 40. The following score range will be used: Low stress: 0 - 13 Moderate stress: 14 - 26 High stress: 27 - 40	Baseline, 6 months, 12 months and 24 months upon randomisation.
Health Behaviour: Social Support	Change in social support scores will be assessed using the Multidimensional Scale of Perceived Social Support (MSPSS). It consists of 12-items on a 7-point Likert scale ranging from 1 (very strongly disagree) to 5 (very strongly agree), for a maximum possible score of 84. A higher score will indicate higher perceived social support.	Baseline, 6 months, 12 months and 24 months upon randomisation.
Health Behaviour: Medication Adherence	Change in medication adherence will be assessed using the Medication Adherence Report Scale (MARS). The scale consists of 5-items on a 5-point Likert scale ranging from 1 (never) to 5 (always), with total scores ranging between 5 - 25. Higher scores indicate higher medication adherence.	Baseline, 6 months, 12 months and 24 months upon randomisation.
Health Behaviour: Dietary Behaviour	Change in dietary behaviour will be assessed by the Health Promotion Board Singapore Dietary Questionnaire published in the 2010 National Nutrition Survey. The scale consists of 8 items assessing the consumption frequency of fruits and vegetables, wholemeal products, sweetened drinks and food bought from eateries.	Baseline, 6 months, 12 months and 24 months upon randomisation.
Health-related quality of life	Change in health-related quality of life will be assessed using the EQ-5D-5L. The EQ-5D-5L questionnaire will be used to evaluate the health-related quality of life of an individual to derive a 5-digit health profile code (e.g. 11211) and utility score (0 = worse than death; 1 = full health).	Baseline, 6 months, 12 months, 24 months from enrolment.
Work Productivity and Activity Impairment Questionnaire: General Health V2.0 (WPAI)	Work Productivity and Activity Impairment Questionnaire: General Health V2.0 will be used to assess absenteeism, presenteeism, and work productivity loss. Activity impairment will be measured on a 0-10 scale, with 0 representing no problems and 10 representing severe problems. Total work impairment will be multiplied by the hourly wage to derive the valuation. This will make up part of indirect costs, which will be used for cost effectiveness analysis.	6 months, 12 months and 24 months upon randomisation.
Cost-Effectiveness Analysis (CEA)	Cost effectiveness Analysis (CEA) will be assessed via the incremental cost effectiveness ratio (ICER). Below details the steps required for conducting CEA: Direct costs will adopt a healthcare system perspective, while indirect costs will be from a societal perspective.; Quality-adjusted life years (QALY) will be derived from a cost-survey analysis (direct costs: healthcare resources used will be valued using Singapore-specific unit costs; indirect costs: WPAI questionnaire and informal healthcare costs) and EQ-5D-5L (Singapore-specific value set).; ICER will be derived from the difference in mean costs divided by the difference in QALY between the intervention and the control group.	6 months, 12 months and 24 months upon randomisation.

Collaborators and Investigators

• Sponsor: National University of Singapore
• Collaborators: National Heart Centre Singapore

Publications and helpful links

General Publications

• Dai H, Bragazzi NL, Younis A, Zhong W, Liu X, Wu J, Grossman E. Worldwide Trends in Prevalence, Mortality, and Disability-Adjusted Life Years for Hypertensive Heart Disease From 1990 to 2017. Hypertension. 2021 Apr;77(4):1223-1233. doi: 10.1161/HYPERTENSIONAHA.120.16483. Epub 2021 Feb 15.
• Wang K, Deng Y, Xiao H. Exercise and cardiac fibrosis. Current Opinion in Physiology. 2023;31(100630)doi:https://doi.org/10.1016/j.cophys.2022.100630
• González A, López B, Ravassa S, et al. Myocardial Interstitial Fibrosis in Hypertensive Heart Disease: From Mechanisms to Clinical Management. Hypertension. Feb 2024;81(2):218-228. doi:10.1161/hypertensionaha.123.21708
• Lawson CA, Zaccardi F, Squire I, Okhai H, Davies M, Huang W, Mamas M, Lam CSP, Khunti K, Kadam UT. Risk Factors for Heart Failure: 20-Year Population-Based Trends by Sex, Socioeconomic Status, and Ethnicity. Circ Heart Fail. 2020 Feb;13(2):e006472. doi: 10.1161/CIRCHEARTFAILURE.119.006472. Epub 2020 Feb 14.

Study record dates

Study Major Dates

• Study Start (Estimated): April 1, 2026
• Primary Completion (Estimated): June 1, 2028
• Study Completion (Estimated): June 1, 2028

Study Registration Dates

• First Submitted: March 17, 2026
• First Submitted That Met QC Criteria: April 8, 2026
• First Posted (Actual): April 15, 2026

Study Record Updates

• Last Update Posted (Actual): April 15, 2026
• Last Update Submitted That Met QC Criteria: April 8, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Hypertension
• Other Study ID Numbers: 2024-3874; OFLCG22may-0010 (Other Grant/Funding Number: National Medical Research Council)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: Due to the extensiveness of the clinical parameters and self-reported data, there could be exploratory analyses conducted in the future. As such, there are no current plans to share IPD.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No