Out-Patient Proactive Observation With Wearable-Assisted Tracking for Cardiovascular Health Management (OPPO-WATCH)

Participants receive wearable device-based, LE8-guided management with access to their monitoring data, health and medication reminders, and individualized LE8 score feedback, together with routine in-person cardiology outpatient follow-up every three months for 12 months.

The smartwatch displays monitoring information, including physical activity and sleep data, and continuously uploads collected data to the study platform through encrypted transmission. The accompanying app collects questionnaires on smoking, diet, and medication use, which are verified during follow-up visits. The system provides reminders related to insufficient physical activity, prolonged sedentary time, insufficient sleep, smoking cessation or reduction, diet, and medication use. After each in-person follow-up visit, the system integrates wearable data, questionnaire responses, and clinical measurements to generate an LE8 cardiovascular health score report for the participant, with individualized prompts for components that do not meet target levels. Follow-up physicians remain masked to wearable monitoring data and LE8 reports and provide clinical care and medication adjustments based on routine clinical information.

Participants wear a smartwatch for data collection but do not have access to monitoring data, health or medication reminders, or Life's Essential 8 (LE8) score feedback. They receive routine in-person cardiology outpatient follow-up every three months for 12 months.

The smartwatch displays only the time while collecting physical activity and sleep data. Monitoring data are not accessible to participants or follow-up physicians. The accompanying app collects questionnaires on smoking, diet, and medication use, which are verified during follow-up visits. The system does not provide health or medication reminders, scores, or feedback to participants. Collected data are encrypted and uploaded to a blinded backend for outcome assessment and quality control. LE8 scores are calculated automatically and exported for endpoint analysis after follow-up is completed. During routine in-person visits, physicians assess participants using clinical interviews, physical examinations, and necessary ancillary tests, and adjust medications and follow-up management without access to wearable monitoring data or LE8 scores.

The primary outcome is the between-group difference in the change in the American Heart Association's Life's Essential 8 (LE8) cardiovascular health score from baseline to 12 months. The LE8 score is calculated automatically by the cloud-based system using data on eight cardiovascular health components: physical activity, sleep health, nicotine exposure, diet, blood pressure, blood glucose, blood lipids, and body mass index. Each component is scored from 0 to 100, and the overall LE8 score is calculated as the unweighted average of the eight component scores, ranging from 0 to 100. Higher scores indicate better cardiovascular health.

The Life's Essential 8 (LE8) Blood Lipids component score is calculated based on non-high-density lipoprotein cholesterol (non-HDL-C), defined as total cholesterol minus high-density lipoprotein cholesterol (HDL-C), according to the predefined LE8 scoring criteria. The component score ranges from 0 to 100 points, with higher scores indicating better cardiovascular health in the blood lipids domain. The outcome is the between-group difference in the change in this component score from baseline to 12 months.

The Life's Essential 8 (LE8) Blood Glucose component score is calculated based on blood glucose-related measurements according to the predefined LE8 scoring criteria. The component score ranges from 0 to 100 points, with higher scores indicating better cardiovascular health in the blood glucose domain. The outcome is the between-group difference in the change in this component score from baseline to 12 months.

The Life's Essential 8 (LE8) Blood Pressure component score is calculated based on measured systolic and diastolic blood pressure according to the predefined LE8 scoring criteria. The component score ranges from 0 to 100 points, with higher scores indicating better cardiovascular health in the blood pressure domain. The outcome is the between-group difference in the change in this component score from baseline to 12 months.

The Life's Essential 8 (LE8) Body Mass Index component score is calculated based on body mass index (BMI), derived from measured height and weight, according to the predefined LE8 scoring criteria. The component score ranges from 0 to 100 points, with higher scores indicating better cardiovascular health in the body mass index domain. The outcome is the between-group difference in the change in this component score from baseline to 12 months.

The Life's Essential 8 (LE8) Physical Activity component score is calculated based on moderate-to-vigorous physical activity (MVPA), measured using the wearable device according to the predefined LE8 scoring criteria. The component score ranges from 0 to 100 points, with higher scores indicating better cardiovascular health in the physical activity domain. The outcome is the between-group difference in the change in this component score from baseline to 12 months.

The Life's Essential 8 (LE8) Sleep Duration component score is calculated based on sleep duration measured using the wearable device according to the predefined LE8 scoring criteria. The component score ranges from 0 to 100 points, with higher scores indicating better cardiovascular health in the sleep domain. The outcome is the between-group difference in the change in this component score from baseline to 12 months.

The Life's Essential 8 (LE8) Nicotine Exposure component score is calculated based on nicotine exposure assessed using a standardized questionnaire administered through the mobile application according to the predefined LE8 scoring criteria. The component score ranges from 0 to 100 points, with higher scores indicating better cardiovascular health in the nicotine exposure domain. The outcome is the between-group difference in the change in this component score from baseline to 12 months.

The Life's Essential 8 (LE8) Diet component score is calculated based on dietary information collected using a standardized questionnaire administered through the mobile application according to the predefined LE8 scoring criteria. The component score ranges from 0 to 100 points, with higher scores indicating better cardiovascular health in the dietary domain. The outcome is the between-group difference in the change in this component score from baseline to 12 months.

Proportion of participants with a Life's Essential 8 (LE8) cardiovascular health score ≥80 points at 12 months. The LE8 score ranges from 0 to 100, with higher scores indicating better cardiovascular health.

Cardiovascular health will be assessed using the American Heart Association's Life's Essential 8 (LE8) cardiovascular health score, which ranges from 0 to 100, with higher scores indicating better cardiovascular health. The change in LE8 score will be calculated as the 12-month score minus the baseline score. An improvement is defined as an increase of at least 5 points. The proportion of participants meeting this criterion will be calculated.

Cardiovascular health will be assessed using the American Heart Association's Life's Essential 8 (LE8) cardiovascular health score, which ranges from 0 to 100, with higher scores indicating better cardiovascular health. The change in LE8 score will be calculated as the 12-month score minus the baseline score. An improvement is defined as an increase of at least 10 points. The proportion of participants meeting this criterion will be calculated.

Cardiovascular health will be assessed using the American Heart Association's Life's Essential 8 (LE8) cardiovascular health score, which ranges from 0 to 100, with higher scores indicating better cardiovascular health. The change in LE8 score will be calculated as the 12-month score minus the baseline score. An improvement is defined as an increase of at least 15 points. The proportion of participants meeting this criterion will be calculated.

The incidence of the composite endpoint of MACE, including cardiac death, acute myocardial infarction, hospitalization for heart failure, and coronary revascularization.

The incidence of cardiac death.

The incidence of acute myocardial infarction.

The incidence of hospitalization for heart failure.

The incidence of coronary revascularization.

The incidence of newly diagnosed diabetes mellitus during the 12-month follow-up period among participants without diabetes at baseline. New-onset diabetes will be identified based on clinical diagnosis and/or standard diagnostic criteria, including HbA1c ≥6.5%, fasting plasma glucose ≥7.0 mmol/L, or 2-hour plasma glucose ≥11.1 mmol/L during an oral glucose tolerance test. In the absence of unequivocal hyperglycemia, confirmatory testing is required. The incidence will be compared between the two study groups.

The incidence of newly diagnosed hypertension during the 12-month follow-up period among participants without hypertension at baseline. New-onset hypertension will be identified based on a documented clinical diagnosis or repeated office blood pressure measurements showing systolic blood pressure ≥140 mmHg and/or diastolic blood pressure ≥90 mmHg, with confirmation according to applicable clinical guidelines. The incidence will be compared between the two study groups.

Changes in mean heart rate during waking hours (daytime) recorded by 24-hour Holter monitoring. Smartwatch data will be used as a reference for consistency assessment.

Changes in mean heart rate during sleeping hours (nighttime) recorded by 24-hour Holter monitoring. Smartwatch data will be used as a reference for consistency assessment.

Changes in mean heart rate over the full 24-hour period recorded by Holter monitoring. Smartwatch data will be used as a reference for consistency assessment.

Resting heart rate is defined as the 1-minute heart rate measured after at least 5 minutes of continuous rest without apparent physical activity. Resting heart rate will be primarily assessed using 24-hour Holter monitoring performed within 1 week before the 12-month visit. Under investigator supervision in a quiet hospital setting, the start and end of the resting period will be recorded, and the mean of three consecutive 1-minute heart rate measurements obtained after 5 minutes of rest will be used. Target resting heart rate is defined as 55-65 beats per minute. The proportion of participants achieving the target range at 12 months will be compared between the two study groups.

Change in heart rate deceleration capacity (DC) from baseline to 12 months, calculated from 24-hour Holter recordings to assess autonomic regulatory function. Changes will be compared between study groups.

Change in heart rate acceleration capacity (AC) from baseline to 12 months, calculated from 24-hour Holter recordings to assess autonomic regulatory function. Changes will be compared between study groups.

Changes in arrhythmia and electrophysiological parameters assessed by 24-hour Holter monitoring, including premature ventricular contractions (PVCs), PVC burden, non-sustained ventricular tachycardia (NSVT), significant bradycardia, pauses >2 seconds, second-degree or higher atrioventricular block.

New-onset AF is defined as the absence of AF evidence on baseline 12-lead ECG and 24-hour Holter, followed by the documentation of an AF episode lasting ≥30 seconds via ECG or Holter during the follow-up period.

The percentage of time in atrial fibrillation relative to the total recording time (%) derived from 24-hour Holter monitoring. Assessed at baseline and 12 months.

Changes in LDL-C levels from baseline to 12 months. Blood samples will be collected at the study site for laboratory analysis.

Changes in HbA1c levels from baseline to 12 months. Blood samples will be collected at the study site for laboratory analysis.

Changes in FBG levels from baseline to 12 months. Blood samples will be collected at the study site for laboratory analysis.

Changes in UA levels from baseline to 12 months. Blood samples will be collected at the study site for laboratory analysis.

Changes in plasma homocysteine levels from baseline to 12 months. Blood samples will be collected at the study site for laboratory analysis.

Changes in cardiovascular medication use, including guideline-directed therapies such as antiplatelet agents, lipid-lowering medications, β-blockers, and renin-angiotensin system inhibitors, will be assessed from baseline to 12 months. Changes in the use of each medication class will be compared between the two study groups.

Change in medication adherence from baseline to 12 months, assessed using the Adherence to Refills and Medications Scale (ARMS).

The EuroQol 5-Dimension 5-Level (EQ-5D-5L) questionnaire assesses health in five dimensions: Mobility, Self-Care, Usual Activities, Pain/Discomfort, and Anxiety/Depression. Each dimension has five response levels, ranging from no problems to extreme problems or inability to perform. Responses across the five dimensions define a health state, which is represented by an EQ-5D-5L index value.

The EuroQol Visual Analogue Scale (EQ VAS) is a self-rated measure of overall health status. Scores range from 0 to 100, where 0 represents the worst imaginable health state and 100 represents the best imaginable health state. Higher scores indicate better perceived health status. The change in EQ VAS score from baseline to 12 months and the between-group difference in score changes will be assessed.

Depressive symptoms will be assessed using the Patient Health Questionnaire-9 (PHQ-9), a 9-item self-report questionnaire assessing depressive symptoms over the preceding 2 weeks. Each item is scored from 0 to 3, yielding a total score ranging from 0 to 27. Higher total scores indicate more severe depressive symptoms and a worse outcome. The change in PHQ-9 total score from baseline to 12 months and the between-group difference in score changes will be assessed.

The proportion of participants achieving the target blood pressure control (<130/80 mmHg) at 12 months.

Change in peripheral oxygen saturation (percentage points) from baseline to 12 months.

Difference in estimated life expectancy (years) between the two groups, derived from the observed difference in Life's Essential 8 (LE8) scores at 12 months using a prespecified life-expectancy estimation model.

Exploratory changes from baseline to 12 months in time-domain heart rate variability parameters, including SDNN, SDANN, RMSSD, and pNN50, derived from 24-hour Holter recordings. Changes will be compared between the two study groups. Continuous smartwatch-derived heart rate data will be used as supplementary information.

Depressive symptoms will be assessed using the Patient Health Questionnaire-9 (PHQ-9), a 9-item self-report questionnaire with a total score ranging from 0 to 27. Higher scores indicate more severe depressive symptoms. A total score of 10 or higher will be used to identify participants with clinically significant depressive symptoms. The proportion of participants with a PHQ-9 total score of 10 or higher at 12 months will be compared between the intervention and control groups. A positive screening result does not establish a clinical diagnosis of major depressive disorder.

Pre-specified exploratory outcome. The average number of steps taken per day, continuously recorded by smartwatches throughout the study period.

Pre-specified exploratory outcome. The average duration of sedentary behavior per day, continuously recorded by smartwatches throughout the study period.

Pre-specified exploratory outcome. The total duration of aerobic exercise accumulated per week, continuously recorded by smartwatches throughout the study period

Pre-specified exploratory outcome. The average energy expenditure (calories) per day, continuously recorded by smartwatches throughout the study period.

Pre-specified exploratory outcome. The average duration of smartwatch wear time per day, used to assess participant adherence to the device protocol.

Pre-specified exploratory outcome. The proportion of the study period with data successfully collected by the smartwatch, used to assess data availability.

Pre-specified exploratory outcome. The extent of reduction in heart rate from baseline levels, derived from continuous smartwatch monitoring.

Pre-specified exploratory outcome. The variability or fluctuation of heart rate over time, continuously recorded by smartwatches throughout the study period.

Pre-specified exploratory secondary outcome. The time elapsed from the start of the study to the first instance of achieving the predefined heart rate target.

Usability of the wearable device and accompanying digital health management system will be assessed in the experimental group using the System Usability Scale (SUS) at 12 months. The SUS score ranges from 0 to 100, with higher scores indicating better perceived usability. Results will be summarized descriptively without between-group comparison.

The total number of outpatient visits per participant from baseline through 12 months will be assessed using medical records and structured follow-up records. The outcome will be reported as the number of outpatient visits per participant and compared between the two study groups.

Exploratory assessment of direct medical costs in both study groups, collected from baseline through 12 months in relation to healthcare resource utilization.

The total number of emergency department visits per participant from baseline through 12 months will be assessed using medical records and structured follow-up records. The outcome will be reported as the number of emergency department visits per participant and compared between the two study groups.

The total number of all-cause hospital admissions per participant from baseline through 12 months will be assessed using hospitalization records and structured follow-up records. The outcome will be reported as the number of hospitalizations per participant and compared between the two study groups.

The cumulative length of hospital stay per participant from baseline through 12 months will be calculated by summing the duration of all hospitalizations, based on hospital admission and discharge records. The outcome will be reported in days per participant and compared between the two study groups.

The total number of cardiovascular-related diagnostic examinations per participant from baseline through 12 months will be assessed using medical records and structured follow-up records. The outcome will be reported as the number of examinations per participant and compared between the two study groups.

The incremental cost-effectiveness ratio (ICER) of wearable device-based management compared with routine care will be evaluated over 12 months. The ICER will be calculated as the between-group difference in mean cumulative direct medical costs divided by the between-group difference in mean quality-adjusted life-years (QALYs) accrued during the 12-month follow-up period. QALYs will be estimated using health utility index values derived from the EuroQol 5-Dimension 5-Level (EQ-5D-5L) questionnaire at baseline and 12 months. The outcome will be reported in Chinese yuan (CNY) per QALY gained.

The incremental cost-effectiveness ratio (ICER) of wearable device-based management compared with routine care will be evaluated over 12 months. The ICER will be calculated as the between-group difference in mean cumulative direct medical costs divided by the between-group difference in mean change in the Life's Essential 8 (LE8) cardiovascular health score from baseline to 12 months. The LE8 score ranges from 0 to 100, with higher scores indicating better cardiovascular health. The outcome will be reported in Chinese yuan (CNY) per additional 1-point improvement in LE8 score.