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Breaking up Sedentary Time in Rheumatoid Arthritis

Not Applicable
Recruiting
Conditions
Endothelial Dysfunction
Rheumatoid Arthritis
Sedentary Behavior
Interventions
Behavioral: Physical activity
Registration Number
NCT05284110
Lead Sponsor
Liverpool John Moores University
Brief Summary

This study will verify the effects of breaking up sitting time with short bouts of light intensity walking on vascular function in women with rheumatoid arthritis.

Detailed Description

Women diagnosed with rheumatoid arthritis will participate in this randomized crossover trial. In one of the experimental sessions, the participants will remain 4-h on uninterrupted sitting, and in another day they will perform 3-min light intensity walk every 30 min to break up the sitting position. Vascular function will be assessed before and after each intervention using the following devices/techniques: a) transcranial Doppler ultrasound to assess the middle cerebral artery blood flow velocity at baseline and in response to CO2 breathing (5% CO2 mixture for 3 min), and to repeated sit-to-stand transitions; b) a multi-frequency linear transducer (7-12 MHz) attached to a high-resolution ultrasound machine to assess femoral artery dilation after reactive hyperemia (i.e., flow-mediated dilation); c) a laser Doppler probe attached to the skin surface of the right shin in order to quantify the Laser Doppler flux at baseline and during reactive hyperemia. Additionally, healthy age- and body mass-matched women will be recruited and will only perform the pre-intervention tests.

Recruitment & Eligibility

Status
RECRUITING
Sex
Female
Target Recruitment
12
Inclusion Criteria
  • Adult women diagnosed with RA
  • From the Rheumatology Clinic at the Liverpool University Hospitals NHS Foundation Trust
  • Aged 18-60 yr
  • Non-smoker for at least 6months
  • Able to provide written informed consent.
Exclusion Criteria
  • Cannot readily read and understand English.
  • Currently smoking or within last 6 months.
  • Alcohol consumption >14units per week.
  • Symptoms of or established cardiovascular disease (except hypertension)
  • Previous stroke or myocardial infarction.
  • History of diabetes or respiratory disease or chronic kidney disease.
  • Musculoskeletal impairment/disability precluding physical activity
  • Unstable medication (change in medication within the 3 months)
  • Aged <18 or > 60 yr
  • Currently pregnant

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
Walking breaks (WALK)Physical activityDuring this session, participants will be requested to remain seated during 4 hours, but the sitting will be interrupted every 30 min with a 3-min light-intensity walking.
Primary Outcome Measures
NameTimeMethod
Middle cerebral artery mean velocity (MCAV)Change from baseline (hour 0) to hour 4 (post-intervention/control)

MCAV will be assessed using continuous bilateral transcranial Doppler ultrasound.

Middle cerebral artery mean velocity reactivity to carbon dioxideChange from baseline (hour 0) to hour 4 (post-intervention/control)

Participants will breathe a 5% carbon dioxide mixture for 3 min during which time MCAV reactivity to CO2 will be assessed using continuous bilateral transcranial Doppler ultrasound.

Cerebral autoregulationChange from baseline (hour 0) to hour 4 (post-intervention/control)

Participants will be asked to complete a series of repeated sit to stand moves (coached by a member of the research team) for a 5-minute period, during which time MCAV will be assessed using continuous bilateral transcranial Doppler ultrasound. Beat by beat blood pressure will also be assessed using finger photoplethysmography.

Secondary Outcome Measures
NameTimeMethod
Brachial artery endothelial functionChange from baseline (hour 0) to hour 4 (post-intervention/control)

Brachial artery endothelial function will be assessed through flow-mediated dilation using vascular ultrasound.

Brachial artery blood flowChange from baseline to 1-hour/2-hour/3-hour/4-hour

Vascular ultrasound will be used to assess brachial artery blood flow every hour during the intervention

Femoral artery blood flowChange from baseline to 1-hour/2-hour/3-hour/4-hour

Vascular ultrasound will be used to assess femoral artery blood flow every hour during the intervention

Pain intensityChange from baseline to 1-hour/2-hour/3-hour/4-hour

Pain intensity will be assessed using a 10cm visual analogue scale.

Finger blood pressureChange from baseline (hour 0) to hour 4 (post-intervention/control)

During all procedures, beat by beat finger blood pressure will be measured on the middle finger of the right hand using photoplethysmography.

Skin blood flow response to hyperemiaChange from baseline (hour 0) to hour 4 (post-intervention/control)

Skin blood flow response to hyperemia will be assessed using a laser doppler probe attached to the shin and forearm.

Stroop color-word testChange from baseline (hour 0) to hour 4 (post-intervention/control)

The Stroop color-word test will be implemented to assess attention and inhibitory control.

Superficial femoral artery endothelial functionChange from baseline (hour 0) to hour 4 (post-intervention/control)

Superficial femoral artery endothelial function will be assessed through flow-mediated dilation using vascular ultrasound.

California Verbal Learning Test-2Change from baseline (hour 0) to hour 4 (post-intervention/control)

Immediate recall of the California Verbal Learning Test-2 will be used to assess verbal learning and memory.

Trial Locations

Locations (1)

Research Institute for Sport and Exercise Sciences (RISES)

🇬🇧

Liverpool, Merseyside, United Kingdom

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