Relationship between BP variability, aortic and cerebral haemodynamics
Research type
Research Study
Full title
A physiological study to determine relationships between changes in variability in systolic blood pressure, arterial stiffness, aortic blood pressure and cerebrovascular pulsatility
IRAS ID
127555
Contact name
Peter M Rothwell
Contact email
Sponsor organisation
University of Oxford
Research summary
Differences in an individual’s blood pressure (BP) from one day to another strongly predicts the risk of a future stroke, independent of average BP. However, it is unclear whether there are associated differences in regulation of blood flow to the brain that might explain effects on stroke risk. This study aims to assess the relationship between changes in BP within the aorta (the large vessel leaving the heart), pulsatility of blood flow to the brain and BP variability on home and ambulatory monitoring. This study will be carried out in patients with ‘mini’ strokes (TIAs) or non-disabling strokes, who are already part of an observational study , the Oxford Vascular Study. In the Oxford Vascular Study, patients perform self-monitoring of BP at home, a 24 hour ambulatory BP monitor at one month and physiological test including a short ultrasound study of the blood flow to their brain (transcranial Doppler ultrasound) at baseline and one month, and usually receive BP lowering treatment with amlodipine or perindopril as part of standard care. In this study, they will undergo an additional measurement of their aortic BP and stiffness with a specialised BP machine, physically indistinguishable from a standard BP machine (Arteriograph)and an additional 24 hour ambulatory BP recording at baseline. To measures differences in BP variability, equal numbers of patients will be given amlodipine or perindopril at random, both of which are recommended by guidelines as standard care. We will analyse if changes in variability in BP are related to changes in pulsatility of blood flow in the brain and the aorta, and stiffness of the aorta. Participants will be recruited by a Stroke Physician after recruitment to the Oxford Vascular Study, at the time of their initial assessment. The study is funded by the NIHR Oxford Biomedical Research Centre and Medical Research Council.
REC name
South Central - Oxford A Research Ethics Committee
REC reference
13/SC/0245
Date of REC Opinion
2 Jul 2013
REC opinion
Further Information Favourable Opinion