POP-HT (Physician Optimised Post-partum Hypertension Treatment)
This trial is looking at the impact that blood pressure control has on women who have had a hypertensive pregnancy (pre-eclampsia or gestational hypertension). We plan to assess whether blood pressure self-management at home can improve blood pressure control and, whether any reduction in blood pressure in these first few months after giving birth can reduce the long-term effects these conditions have on the heart, brain and blood vessels.
Length of project: 2 years
Funded by: The research is being financed by a British Heart Foundation Clinical Research Training Fellowship (BHF Grant number FS/19/7/34148)
Chief investigator/PI: Prof Paul Leeson, Professor of Cardiovascular Medicine
Lead Researcher: Dr Jamie Kitt, Senior Cardiology Speciality Registrar and British Heart Foundation Clinical Research Fellow
Assistant Researcher: Dr Annabelle Frost, Obstetric Clinical Research Fellow, Cardiovascular Clinical Research Facility (CCRF), Division of Cardiovascular Medicine, University of Oxford
Supervisors:
Prof Richard McManus, Professor of Primary Care, Nuffield Department of Primary Care Health Sciences, University of Oxford)
Dr Adam Lewandowski (University Research Lecturer and British Heart Foundation Intermediate Research Fellow Radcliffe Department of Medicine, University of Oxford)
Co-investigators:
Dr Lucy Mackillop, Consultant Obstetric Physician, Oxford University Hospitals NHS Trust, John Radcliffe Hospital
Dr Adam Lewandowski, University Research Lecturer and British Heart Foundation Intermediate Research Fellow, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford
Dr Christina Aye, NIHR Academic Clinical Lecturer and Speciality trainee in Maternal Fetal Medicine
Dr Katie Suriano, Research assistant, Cardiovascular Clinical Research Facility (CCRF), Division of Cardiovascular Medicine, University of Oxford
Mrs Yvonne Kenworthy, Senior research mid-wife Cardiovascular Clinical Research Facility (CCRF), Division of Cardiovascular Medicine, University of Oxford
Mrs Annabelle McCourt, Research assistant, Cardiovascular Clinical Research Facility (CCRF), Division of Cardiovascular Medicine, University of Oxford
Dr Katherine Tucker, Senior Researcher, Nuffield Department of Primary Care Health Sciences, University of Oxford
Dr Alexandra Cairns, Obstetric Speciality Registrar OUH NHS Foundation Trust
Dr Mauro Santos, Post-doctoral research fellow, OIBME, University of Oxford
Dr Cristian Roman, Post-doctoral research fellow, OIBME, University of Oxford
External Collaborators:
Professor Basky Thilaganathan, Director, Maternal-fetal Medicine Unit, St George’s University Hospitals NHS Foundation Trust
Professor Lucy Chappell, NIHR Research Professor in Obstetrics, King's College London and Honorary Consultant Obstetrician
Summary:
Our group has shown in a pilot randomised controlled study [SNAP-HT; REC 14/SC/1316] that blood pressure self-management during the post-partum period after hypertensive pregnancies, may result in lower blood pressure after six months; even when medication has been stopped.
We now want to assess whether this blood pressure reduction can be reproduced in this larger, randomised controlled trial [POP-HT; REC 19/LO/19901], and whether any blood pressure lowering has additional benefits in terms of other cardiovascular and cerebrovascular remodelling, which are known to occur by 5-10 years after giving birth in women who have had a hypertensive pregnancy.
This trial of self-management in the post-partum period will utilise updated Blue-tooth® enabled blood pressure monitoring alongside a proprietary POP-HT app, coupled to physician-assisted dose titration to further advance the self-management aspect of the intervention. The physicians will be specialist clinicians who form part of the research team. We will measure additional structural and functional end organ differences, using magnetic resonance imaging of the brain and heart, as well as echocardiography and retinal imaging.
This study will provide insight into the impact of post-partum blood pressure control on the maternal cardiovascular system and how this associates with blood pressure changes. Together, these studies will help refine future intervention strategies in this cohort of patients.
Why is this study important?
High blood pressure disorders in pregnancy are associated with an increased risk of high blood pressure, heart attack and stroke in later life. The risks associated with high blood pressure in pregnancy can be mitigated by early recognition and treatment of raised blood pressure (and other traditional cardiovascular risk factors e.g. lack of regular exercise, eating an unhealthy diet).
This trial is looking at the impact that blood pressure control has on these long-term risks. We plan to assess whether blood pressure self-management can improve blood pressure control and whether this reduction in blood pressure in the months after birth can reduce the long-term effects these conditions have on your heart, brain and blood vessels, hopefully reducing the following risks associated with pre-eclampsia (as defined in NICE NG 133 July 2019):
1 in 5 women having another hypertensive pregnancy
1 in 7 women having another pre-eclamptic pregnancy
A 4 fold increase in risk of having long term high blood pressure
A 2 fold increase in risk of experiencing both cardiovascular death or a heart attack
A 1.5 fold increase in risk of having a stroke
(adapted from NICE NG 133: Hypertension in pregnancy July 2019)
Summary of the methodology:
High blood pressure occurs in ~1 in 10 women during pregnancy and remains elevated in 50% even after the baby is born requiring medication at home after discharge.
This study is investigating whether, ‘self- management’ of blood pressure (BP) at home, after discharge, can improve blood pressure control and reduce the longer-term impact on the heart and brain.
50% of participants (the self-management group) will be asked to measure their blood pressure at home using a Wireless OMRON Evolv ® blood pressure monitor and upload the readings via the proprietary smart-phone/tablet POP-HT app®.
If readings are abnormal then a specialist doctor will supervise medication adjustment accordingly (participants will still have option of seeing their own GP/midwife if they prefer).
50% (the control group) will be looked after by their GP/ midwife/other NHS services as normal. The group participants are allocated to will be decided at random (i.e. it is a randomised trial).
The study starts after giving birth and runs up-to 6-9 months after discharge from hospital and both the intervention and control group will have 4 study visits as part of the trial.
The team are aware that you all participants will have a new born baby/babies so study visits will be very flexible and can stop-start around feeding, nappy changes and other important baby needs.
N.B. All women will continue to receive routine NHS care throughout.
Next steps
Recruitment will commence in February 2020, initially in Oxford at the John Radcliffe Hospital, with plans to expand to other sites over the coming months.
