Sitting Interruption and Whole-body Cardiovascular Health (SWITCH)

Sitting Interruption and Whole-body Cardiovascular Health: Linking Physiological Responses to Risk Behaviors

There is strong evidence for the association between sedentary behaviors and cardiovascular diseases such as coronary heart disease and stroke. However, the public currently has no clear guidance on how to limit or interrupt their sedentary behaviors. This study will identify and test the physiological effects of several sedentary behavior interruption strategies and explore the feasibility (i.e., likelihood of an individual performing the requested activities) of those strategies to inform the development of public policy surrounding sedentary behavior interruption. Long-term, the findings of this study will inform a large clinical trial that can test whether sedentary behavior reduction can decrease cardiovascular disease risk.

Study Overview

• Status: Recruiting
• Conditions: Sedentary Behavior; Sedentary Time
• Intervention / Treatment: Behavioral: One 5-Minute Walking Bout Each Hour; Behavioral: One 15-Minute Standing Bout Each Hour; Behavioral: One 5-Minute Walking Bout and One 15-Minute Standing Bout Each Hour; Behavioral: Uninterrupted Sitting

Detailed Description

Sedentary behaviors (SB) are biologically distinct but understudied heart disease risk factors. National and international agencies have concluded that the level of evidence for an overall and dose-response association between SB and heart disease mortality is moderate-strong. These agencies do not provide specific recommendations for breaking-up SB, though do call on the research community to facilitate policy development by establishing biological plausibility, identifying the optimal dose for SB substitution strategies, and conducting randomized clinical trials to test the efficacy of these strategies. Accordingly, the goal of this study is to identify mechanism-informed, socioecological-based SB substitution recommendations to reduce heart disease risk. To achieve this goal, two aims will be addressed. Aim 1 will identify a feasible SB substitution strategy to prevent the negative cardiovascular responses to prolonged SB (i.e., strategies that people will actually follow). Adverse cardiovascular responses to prolonged SB will be measured using aortic arterial stiffness (AS), a noninvasive test that predicts future heart disease. To accomplish this aim, 56 middle-aged (36-55 years) participants will provide written informed consent, prior to the measurement of aortic AS and associated mechanistic responses to the following over 4 hours, in a randomized crossover manner: (i) SB with a 5-minute walk break once per hour; (ii) SB with a 15-minute standing break once per hour; (iii) SB with two breaks per hour, alternating between a 5-minute walk and a 15-minute stand; and (iv) SB with no breaks (control). These strategies were selected based on extensive prior work by the investigators, and because they are feasible, which is a key component of this study. SB reduction strategies will only decrease heart disease risk if people are willing to adhere to future SB substitution recommendations. To increase the likelihood of feasibility and long-term adherence, Aim 2 will evaluate the determinants of SB using a socioecological model. This recognizes that behavior change is likely to be limited if the physical and sociocultural environments do not support the behavior change. To accomplish Aim 2, a combined inductive-deductive qualitative approach will be used. Participants who complete Aim 1 will participate in one of 6 focus groups (6-8 participants/group). Crucially, the outcomes from this proposal will be instrumental in helping to design a subsequent clinical trial to test a mechanism-informed yet feasible SB reduction intervention, and in doing so directly support the development of SB policy.

• Study Type: Interventional
• Enrollment (Estimated): 56
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Simon Higgins, PhD; Phone Number: (706) 461-6776; Email: higginss@unc.edu

Study Locations

• United States
  • North Carolina
    • Chapel Hill, North Carolina, United States, 27599
      • Recruiting
      • University of North Carolina at Chapel Hill
      • Contact: Simon Higgins, PhD; Phone Number: 706-461-6776; Email: higginss@unc.edu
      • Sub-Investigator: Erik D Hanson, PhD
      • Sub-Investigator: Gaurav J Dave, DrPH
      • Sub-Investigator: Christopher P Mack, PhD
      • Sub-Investigator: Michelle Meyer, PhD
      • Sub-Investigator: Feng-Chang Lin, PhD
      • Sub-Investigator: Bethany Barone Gibbs, PhD
      • Sub-Investigator: Maihan Vu, DrPH

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 36 years to 55 years (Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Aged between 36-55 years
• Insufficiently active: self-reported exercise <90 minutes per week for the past 3 months
• Sedentary: self-reported sitting >8 hours per day
• Self-reported ability to walk 4 blocks and climb 2 flights of stairs
• Possession of cellular phone able to receive text messages

Exclusion Criteria:

• Use of assisted-walking devices
• Comorbid condition that would limit the ability to reduce sedentary behavior (e.g., musculoskeletal condition, current chemotherapy)
• Plans for major surgery within next 3 months
• Recent history (<1 year) of ischemic heart disease, chronic heart failure, stroke, or chronic kidney disease
• Recent (< 1 year) or planned bariatric surgery
• Systolic blood pressure ≥160 mmHg or diastolic blood pressure ≥100 mmHg
• Current or recent (within last 6 months) pregnancy; current or recent (within last 3 months) breastfeeding
• Morbidly obesity (BMI >40 kg/m^2) or underweight (BMI <18.5 kg/m^2)
• Use of anti-hypertensive drugs
• Use of glucose-controlling medication
• Heavy alcohol consumption (>15 drinks per week)

Study Plan

How is the study designed?

Design Details

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

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: One 5-Minute Walking Bout Each Hour; A 4-hour sedentary behavior bout, during which the participant remains seated while watching a non-stimulatory documentary. The interruption strategy includes breaking up the 4-hour sitting bout with one 5-minute light intensity walking bout each hour. Each participant will be re-randomized to any of the non-completed arms after completion of the initial 4-hour sitting bout and interruption strategy until all arms have been completed.	Behavioral: One 5-Minute Walking Bout Each Hour; One 5-minute light intensity walking break per hour throughout the 4-hour SB condition
Active Comparator: One 15-Minute Standing Bout Each Hour; A 4-hour sedentary behavior bout, during which the participant remains seated while watching a non-stimulatory documentary. The interruption strategy includes breaking up the 4-hour sitting bout with one 15-minute standing bout each hour. Each participant will be re-randomized to any of the non-completed arms after completion of the initial 4-hour sitting bout and interruption strategy until all arms have been completed.	Behavioral: One 15-Minute Standing Bout Each Hour; One 15-minute standing break per hour throughout the 4-hour SB condition
Active Comparator: One 5-Minute Walking Bout and One 15-Minute Standing Bout Each Hour; A 4-hour sedentary behavior bout, during which the participant remains seated while watching a non-stimulatory documentary. The interruption strategy includes breaking up the 4-hour sitting bout with one 5-minute light intensity walking bout and one 15-minute standing bout each hour. Each participant will be re-randomized to any of the non-completed arms after completion of the initial 4-hour sitting bout and interruption strategy until all arms have been completed.	Behavioral: One 5-Minute Walking Bout and One 15-Minute Standing Bout Each Hour; Two breaks per hour throughout the 4-hour SB condition, alternating between a 5-minute light intensity walking break and a 15-minute standing break
Active Comparator: Uninterrupted Sitting; A 4-hour sedentary behavior bout, during which the participant remains seated while watching a non-stimulatory documentary. This uninterrupted sedentary bout will serve as a control. Each participant will be re-randomized to any of the non-completed arms after completion of the initial 4-hour sitting bout and interruption strategy until all arms have been completed.	Behavioral: Uninterrupted Sitting; No breaks will be provided throughout the 4-hour SB condition. This will be used as the control condition

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean Change in Carotid-femoral Pulse Wave Velocity (cfPWV)	cfPWV (m/sec) will be measured between the carotid and femoral arteries, using a collar around the neck and a cuff around the thigh, with the participant in a supine position. cfPWV is calculated by dividing path length by pulse transit time and reported as the mean of three measurements	Measurements will be taken immediately before and after each 4-hour SB condition

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Heart-middle Cerebral Artery Pulse Wave Velocity (Brain PWV)	Brain PWV (cm/sec) is the velocity at which a pressure wave travels between the heart and cerebrovascular system. Brain PWV will be calculated from the ECG r-wave to the foot of the Cerebral Blood Flow Velocity (CBFV) waveform	Measurements will occur continuously throughout each of the 4-hour SB conditions
Mean Change in Femoral-ankle PWV	Femoral-ankle PWV (m/sec) is the velocity at which a pressure wave travels between the femoral-ankle arterial segments. Femoral-ankle PWV is calculated by dividing path length by pulse transit time and reported as the mean of three measurements	Measurements will be taken immediately before and after each 4-hour SB condition

Collaborators and Investigators

• Sponsor: University of North Carolina, Chapel Hill
• Collaborators: National Heart, Lung, and Blood Institute (NHLBI)
• Investigators: Principal Investigator: Lee Stoner, PhD, University of North Carolina, Chapel Hill

Publications and helpful links

General Publications

• Higgins S, Cowley ES, Paterson C, Hanson ED, Dave GJ, Meyer ML, Lin FC, Gibbs BB, Vu M, Stoner L. Protocol for a study on Sitting with Interruption and Whole-Body Cardiovascular Health (SWITCH) in middle-aged adults. Contemp Clin Trials. 2023 Feb;125:107048. doi: 10.1016/j.cct.2022.107048. Epub 2022 Dec 9.

Study record dates

Study Major Dates

• Study Start (Actual): August 15, 2022
• Primary Completion (Estimated): February 28, 2026
• Study Completion (Estimated): February 28, 2026

Study Registration Dates

• First Submitted: March 30, 2022
• First Submitted That Met QC Criteria: March 30, 2022
• First Posted (Actual): April 7, 2022

Study Record Updates

• Last Update Posted (Actual): October 4, 2023
• Last Update Submitted That Met QC Criteria: October 2, 2023
• Last Verified: October 1, 2023

More Information

Terms related to this study

• Keywords: Sedentary Behavior; Interruption; Sitting; Cardiovascular; Arterial Stiffness; Pulse Wave Velocity
• Other Study ID Numbers: 21-3195; 1R01HL157187-01A1 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Deidentified individual data that supports the results will be shared beginning 9 to 36 months following publication provided the investigator who proposes to use the data has approval from an Institutional Review Board (IRB), Independent Ethics Committee (IEC), or Research Ethics Board (REB), as applicable, and executes a data use/sharing agreement with the University of North Carolina.
• IPD Sharing Time Frame: Beginning 9 months following publication and continuing for 36 months
• IPD Sharing Access Criteria: Investigator has IRB, IEC, or REB approval and an executed data use/sharing agreement with UNC.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ANALYTIC_CODE

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No