Endothelial Dysfunction, Rheumatoid Arthritis, Sedentary Behavior
Conditions
Keywords
physical activity, rheumatic diseases, vascular function
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.
Interventions
BEHAVIORALPhysical activity
Multiple bouts of 3-min brisk walking, every 30 min, for 4 hours.
Sponsors
Liverpool University Hospitals NHS Foundation Trust
Liverpool John Moores University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
OTHER
Masking
SINGLE (Outcomes Assessor)
Masking description
The researcher who will perform the vascular analysis will be blinded to the allocation order.
Intervention model description
Participants with rheumatoid arthritis will attend the laboratory at Liverpool John Moores University on 2 occasions. During these visits, they will be submitted to the intervention or the control and will also undertake a series vascular tests prior- and post-intervention/control.
Eligibility
Sex/Gender
FEMALE
Age
18 Years to 60 Years
Healthy volunteers
No
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 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 dioxide | Change 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 autoregulation | Change 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
| Measure | Time frame | Description |
|---|---|---|
| Skin blood flow response to hyperemia | Change 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 test | Change from baseline (hour 0) to hour 4 (post-intervention/control) | The Stroop color-word test will be implemented to assess attention and inhibitory control. |
| California Verbal Learning Test-2 | Change 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. |
| Brachial artery endothelial function | Change from baseline (hour 0) to hour 4 (post-intervention/control) | Brachial artery endothelial function will be assessed through flow-mediated dilation using vascular ultrasound. |
| Femoral artery blood flow | Change 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 intensity | Change from baseline to 1-hour/2-hour/3-hour/4-hour | Pain intensity will be assessed using a 10cm visual analogue scale. |
| Brachial artery blood flow | Change 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 |
| Finger blood pressure | Change 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. |
| Superficial femoral artery endothelial function | Change 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. |
Countries
United Kingdom
Contacts
Primary ContactDaniel Bannell, MPhil
Backup ContactDavid Low, PhD
Outcome results
None listed