Reducing Sedentary Time in Patients With Cardiovascular Disease

The purpose of this study is to develop and test a 12-week sedentary behavior reduction intervention ("Sit Less" program) for patients with cardiovascular disease. The program aims to reduce and break sitting times among this population using an objective activity monitor and mHealth. The investigators will test the program to help cardiovascular disease patients break up sitting time, reduce daily sitting time, and move more. The investigators will also study whether the program leads to improvements in heart disease risk factors, and whether cardiovascular disease patients like the program and can follow it.

The investigators propose to develop and conduct a pilot 2-arm RCT to test a wearable technology-based sedentary behavior reduction intervention in cardiovascular disease patients. Participants will be randomized to either the control group or the sedentary behavior reduction intervention group. The intervention group will target a 120 minute per day reduction in sedentary behavior using an objective activity monitor and mHealth. Specifically, the study aims to: determine the feasibility and acceptability of the sedentary behavior reduction intervention in cardiovascular patients by evaluating reach, retention, satisfaction, and compliance with the intervention; evaluate the preliminary efficacy of the sedentary behavior reduction intervention on changes in sedentary time; and explore preliminary effects of the sedentary reduction intervention on physical activity, cardiometabolic markers and patient-centered outcomes.

The intervention group will target a 120 minute per day reduction in sedentary behavior using an objective activity monitor and mHealth.

The control group will receive usual medical care and American Heart Association's Healthy Living booklet

The intervention group will target a 120 minute per day reduction in sedentary behavior using an objective activity monitor and mHealth. Outcomes will be measured at baseline and post-intervention

Level of satisfaction with the intervention assessed by the System Usability Scale and exit-interview

Level of satisfaction with the intervention will be assessed by using the 10-item of system usability scale. An exit interview will be conducted by the intervention among subsamples of the intervention group (n =20) during the post-intervention visit. The interview will assess the acceptability of and satisfaction with the intervention, barriers and facilitators to sedentary behavior reduction, and any alternate strategies tried by participants during the study.

The compliance with the intervention will be assessed by number of days the Fitbit device was worn per week.

Sedentary behavior will be assessed by three parameters including total daily sedentary time, prolonged sedentary time (time spent sitting >30mins), and numbers of sit-to-stand transition. These three sedentary behavior parameters will be measured by 7 days of activPAL 3 device monitoring.

Cardiometabolic markers including fasting cholesterols, insulin levels, HbA1c, fasting glucose, and hs-CRP will be measured by blood dried spot card. For blood samples, participants will fast overnight (at least 8 hours). The trained RA will conduct a finger prick and 8-9 drops of blood will be obtained on a dried blood spot card.

Changes of confidence in reducing sedentary behavior measured by using 6 items from the Self-Efficacy Questionnaire for Physical Activity and Sedentary Behavior.

Confidence in reducing sedentary behavior will be measured using 6 items from the Self-Efficacy Questionnaire for Physical Activity and Sedentary Behavior.

Habit strength for sedentary behavior will be assessed by 7 items from the Self-Report Sedentary Behavior Habit Index.

24-hour glucose levels will be measured by the use of a continuous glucose monitor over a 7-day period. The 24-hour glucose control will be evaluated by mean 24-hour glucose levels and numbers of events and time in hypoglycaemia (glucose < 3.9 mmol/l), euglycaemia (glucose 3.9-7.8 mmol/l), hyperglycaemia (glucose > 7.8 mmol/l) and above target (glucose > 9 mmol/l).

Inclusion Criteria: Ages 18 and above Have at least one of the following conditions including history of heart attack or peripheral artery disease or a stent placed in heart or leg Self-report of sitting ≥ 8 hr/day Ability to stand and walk Ownership of a smartphone Exclusion Criteria: Currently using an activity tracker Currently participating in exercise of cardiac rehabilitation programs Non-English speaking Patients who are classified as unstable (e.g. heart failure, uncontrolled arrhythmia) or have kidney disease that limits daily water intake, or any other conditions contradictory to standing or walking and Currently pregnant

The investigator does not have plans to share data at this time. In the future, reasonable requests for de-identified data from other scientists will be considered. Such data will be shared with approval by the Study PI and other investigators, as appropriate.