Effect of Reducing Sedentary Behavior on Blood Pressure

Study Overview
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Brief Summary
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This is a 2-arm, 3-month randomized trial comparing a novel sedentary behavior intervention vs. control in working adults (n=300). The primary outcome is resting systolic blood pressure (SBP) at 3 months; secondary outcomes will be resting diastolic blood pressure (DBP), ambulatory blood pressure (ABP), and carotid-femoral pulse wave velocity (cfPWV). Also, best practice objective activity monitoring will be leveraged in the analysis of ABP to account for recent activity and posture and will inform adherence and dose-response relationships.We will also measure plasma renin activity and aldosterone as a potential mechanism of blood pressure reduction, and insulin and glucose as exploratory outcomes.

Detailed Description
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Hypertension (HTN) is the most common major risk factor for cardiovascular disease (CVD), affecting 1 in 3 American adults. Also, nearly another 1 in 3 adults has prehypertension (preHTN). Moderate-to-vigorous intensity physical activity (MVPA) is known to decrease BP. Guidelines recommend 150 min/week of MVPA performed in continuous bouts of ≥10 min (i.e., bouted MVPA). Sedentary behavior (SED), defined as sitting or reclining with low energy expenditure, has gained attention as a highly prevalent and distinct behavior from MVPA that is independently associated with higher BP, arterial stiffness, CVD, and mortality. These data, coupled with the fact that Americans spend more than half of the waking day in SED, suggest SED as a novel intervention target. Yet, despite heightened public perception of SED as a health risk, there is a dearth of randomized clinical trials demonstrating that SED reduction will lead to health benefits, including reduced BP. Decreasing SED more substantially could improve BP, but this remains unclear in the absence of larger randomized trials with effective SED interventions. Thus, to test initial efficacy, the Effect of Reducing Sedentary Behavior on Blood Pressure (RESET-BP) has the following specific aims: Specific aim 1: To evaluate the efficacy of our intervention targeting decreased sedentary behavior (SED) over 3 months. Outcomes include SBP (primary), DBP, ABP (nocturnal, daytime seated, daytime non-seated), and cfPWV. We hypothesize that the 3-month SED intervention will decrease SBP, DBP, ABP and cfPWV vs. controls Specific Aim 2: To explore whether renin-angiotensin-aldosterone (RAAS) activation (increased plasma renin activity (PRA) and aldosterone) mediates changes in BP elicited by SED reduction Specific Aim 3: To examine associations between achieved reductions in SED, increases in replacement behaviors (i.e., standing, other light-intensity physical activity (LPA), and BP reduction These aims will be evaluated with a 2-arm, 3-month randomized trial comparing a novel SED intervention vs. control in 300 adults (150 per group). The study will recruit adults with untreated, elevated blood pressure (SBP 120-159 mmHg or DBP 80-99 mmHg) and desk jobs that require prolonged SED to maximize the opportunity for SED reduction. The intervention will target currently recommended levels of SED reduction for desk-based employees (2-4 hours/day with frequent postural changes) and will use a behavioral intervention including individual in-person (1/month) and phone counselling (1/month) focused on goal setting, overcoming barriers, self-monitoring, social support, and stimulus control. In addition, the intervention will include environmental modification via provision of a sit-stand desk attachment and external prompting via text messaging and a wrist-worn inactivity prompter.

Official Title
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Effect of Reducing Sedentary Behavior on Blood Pressure

Conditions
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Hypertension, Prehypertension

Intervention / Treatment
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* Behavioral: Intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 21-65 years SBP 120-159 mmHg or DBP of 80-99 Inactive (Engages in less than 150 min/wk of moderate + 2 x vigorous intensity physical activity) Currently perform deskwork for ≥ 20 hr/week at a desk compatible with the sit-stand attachment Employment within an approximate 25-mile radius of the University of Pittsburgh Stable employment (≥ 3 months in current job, plan to be in current job for the next 3 months) Supervisor approval to join the intervention Possession of a cellular phone able to receive text messages Exclusion Criteria: SBP ≥ 160 mmHg, DBP ≥ 100 mmHg Use of antihypertensive or glucose controlling medication Comorbid condition that would limit ability to reduce sedentary behavior (e.g. musculoskeletal condition, current chemotherapy) History of ischemic heart disease, chronic heart failure, stroke, or chronic kidney disease Unable to obtain consent from primary care provider or physician to participate Current use of sit-stand/standing desk, sedentary behavior prompting device, enrollment in a weight loss or exercise study or program, recent (< 1 year) or planned bariatric surgery Currently pregnant or pregnant in that last 6 months; breastfeeding currently or in the last 3 months Plans to be away from your desk for an extended period (>1 week) during the study period

Ages Eligible for Study
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Minimum Age: 21 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intervention<br>The intervention will use behavioral strategies (self-monitoring, goal setting, problem solving, social support, stimulus control), environment modification (sit-stand attachment), and proximal (activity prompter) and distal (text messages) external prompts to target a 2-4 hour/day reduction in sedentary behavior. | Behavioral: Intervention<br>* The intervention will be delivered by trained research staff who are exercise physiologists or behavioral lifestyle counselors. This target reflects a recent expert statement concluding that desk-based workers should reduce workday sedentary behavior by 2-4 hr (by increasing standing and movement). The approach will combine: behavioral strategies (self-monitoring, goal setting, problem solving, social support, stimulus control), environment modification (sit-stand attachment), and proximal (activity prompter) and distal (text messages) external prompts. The initial in-person session will occur at the participant's office location. During months 2 and 3, one-on-one in-person meetings will occur at the research lab. Telephone intervention contacts will occur in the 3rd week of months 1-3.<br>* Other names: Sedentary Behavior Reduction;|
| No Intervention: Control<br>Participants randomized to the control condition will receive no intervention during the study. After the 3-month assessment, control participants will be provided with a wrist-worn activity monitor and will be offered the 3-month delayed intervention if desired to aid in retention and recruitment. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Resting Systolic Blood Pressure | Resting systolic blood pressure will be measured at baseline and follow-up using an oscillometric device after a 10-min rest on two occasions | 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 24-hour Ambulatory Blood Pressure | Ambulatory blood pressure will be measured at baseline and 3-month follow-up during a workday and overnight (24 hours total) at the beginning and end of the study. | 3 months | 
| Pulse Wave Velocity | Carotid-femoral and carotid-radial pulse wave velocity will be measured at baseline and follow-up following a 10-min supine rest via tonometry. | 3 months | 
| Plasma Renin Activity | PRA will be measured at baseline and 3-month follow-up. | 3 months | 
| Aldosterone | Aldosterone will be measured at baseline and 3-month follow-up. | 3 months | 
| Diastolic Blood Pressure | Resting diastolic blood pressure will be measured at baseline and follow-up using an oscillometric device after a 10-min rest on two occasions | 3 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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sedentary behavior, light intensity physical activity, behavioral intervention, office workers, blood pressure, pulse wave velocity, randomized clinical trial