ANZCTR - Registration

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Trial registered on ANZCTR

Registration number

ACTRN12618002004246

Ethics application status

Approved

Date submitted

29/11/2018

Date registered

13/12/2018

Date last updated

22/05/2023

Date data sharing statement initially provided

13/12/2018

Date results information initially provided

22/05/2023

Type of registration

Prospectively registered

Titles & IDs

Public title

The BP2 (Blood Pressure Postpartum) study: a 3-arm, randomised trial of follow-up and lifestyle behaviour change strategies in the first 12 months after hypertensive disorders of pregnancy

Scientific title

Improving maternal and infant cardiovascular health trajectories after hypertensive pregnancy: a 3 arm, randomised lifestyle intervention trial

Secondary ID [1]

None

Universal Trial Number (UTN)

U1111-1218-5078

Trial acronym

BP2

Linked study record

N/A

Health condition

Health condition(s) or problem(s) studied:

Preeclampsia

Gestational Hypertension

Chronic Hypertension in pregnancy

Condition category

Condition code

Cardiovascular

Hypertension

Public Health

Health promotion/education

Reproductive Health and Childbirth

Fetal medicine and complications of pregnancy

Intervention/exposure

Study type

Interventional

Description of intervention(s) / exposure

At 6 months postpartum (pp) all participants (women after preeclampsia, gestational hypertension, or chronic hypertension) complete validated questionnaires: NSW Population Health Survey (by telephone), Infant Feeding behaviours, Health-related Quality of Life (EQ-5D-5L), Ages and Stages, Edinburgh Postnatal Depression Score, Generalised Anxiety Disorder and a study designed maternal and infant health questionnaire about health since the birth (hard copy or online). Pregnancy, labour, birth and infant details will be recorded from the hospital maternity database. Blood and urine testing will be done and repeated at 12 months pp.
After completion of baseline questionnaires, women are randomised into one of 3 groups with interventions as below.

Optimised Usual Care (Group 1):
• report their weight, height, and waist circumference to the research staff
• sent package containing readily available information about cardiovascular health after hypertensive disorder of pregnancy (HDP). This information includes:
1. The Heart Foundation infographic titled 'Did you have high blood pressure during pregnancy?'(www.heartfoundation.org.au),
2. The NSW Get Healthy Service (GHS) a free service of phone call counselling to work towards healthy lifestyle changes (www.gethealthynsw.com.au)
3. The link to the 'My Baby Now' app which is free and available on IoS and android phones. This app offers information regarding the baby's development and nutrition advice through to 9-12 months of age.
• visit their GP with their infant at 6 months pp for BP check, weight and their infant’s weight, height and head circumference. GP/medical centre will be sent an information package to assist with this visit. This package will contain an explanatory cover letter, correspondence from the pregnancy/birth care including the hospital discharge summary, the Heart Foundation Information for GPs titled 'Hypertensive Disorders of Pregnancy and Cardiovascular Disease: A guide for GPs' (this consists of two brochures: General Facts and Postpartum Assessment, both freely available on the Heart foundation Website), a copy of the information pack given to the woman (see above) and a copy of the woman's signed study consent form. Details of the GP visit will be sent to the research staff to complete data collection. A reminder phone will be made to the participants regarding booking this appointment with their GP/medical centre.

Brief Education Intervention (Group 2):
• attend hospital with their infant at 6 months pp for maternal measures: peripheral and central BP, height, weight, waist circumference, body composition, and infant measures: weight, length, head and abdominal circumference, blood pressure
• a single 30 minute consultation with an obstetric medicine physician, who will review the personal history and examination findings, educate regarding long-term health implications of HDP, and address cardiovascular risk by offering advice on lifestyle and behavioural change such as quit smoking, exercise and healthy diet.
• see a dietitian for a single 30 minute appointment to review of diet and physical activity, infant’s feeding patterns, and discussion on healthy eating and physical activity.
A reminder text message will be sent a few days prior to theses appointments to remind the participant of the appointment. Data from these visits will be sent to the researcher for data collection and entry into database.

Extended lifestyle intervention (Group 3)
In addition to the intervention for Group 2, research staff will enroll Group 3 participants in the NSW Get Healthy Service (GHS). GHS will then provide, over a 6 month period, up to 13 coaching calls that include initial goal setting and then working towards lifestyle behaviour change goals during program enrollment. A follow-up phone call and text message will be made by trial research staff 2-3 weeks after enrollment into GHS to check that contact has been made between GHS and the participant and that the participant has commenced with the GHS program. Adherence to the GHS will be assessed at the 12 month follow-up visit by the GHS staff who will liaise with study researchers. GHS staff will use the Service records to report on which GHS clients participated in the trial (whether in Group 1, 2, or 3), provide data on whether participants completed (a) initial GHS process (b) full 6-month GHS service (c) for those trial participants who initiated but did not complete, point of GHS termination and any know reason.

Semi structured interviews will be conducted with women from all groups between the 6 and 12 month visits. These interviews will explore the barriers and enablers to adopting healthy eating and physical activity behaviours post-partum and women will be asked their views of the intervention to better understand their engagement. All women will be invited to participate via a question at the end of the women’s 6 month survey and we will purposefully sample from each of the groups to ensure that views are captured about each arm of the intervention.

Intervention code [1]

Lifestyle

Intervention code [2]

Early detection / Screening

Intervention code [3]

Behaviour

Comparator / control treatment

Optimised Usual Care (Group 1-Control Group):
Complete questionnaires: NSW Population Health Survey (by telephone), Infant Feeding behaviours, Health-related Quality of Life (EQ-5D-5L), Ages and Stages, Edinburgh Postnatal Depression Score, Generalised Anxiety Disorder and a study designed maternal and infant health questionnaire about health since the birth (hard copy or online). Pregnancy, labour, birth and infant details will be recorded from the hospital maternity database. Blood and urine testing will be done and repeated at 12 months pp.
Report their weight, height, and waist circumference to research staff
Sent package containing information about cardiovascular health after hypertensive disorder of pregnancy (HDP), Get Healthy Service, and link to Growing Healthy/My Baby now app
Visit their GP with their infant at 6 months pp for BP check, weight and their infant’s weight, height and head circumference.

Control group

Active

Outcomes

Primary outcome [1]

Change in systolic blood pressure measured using the average of three measurements from a validated automated blood pressure device; the Omron HEM-907

Timepoint [1]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values).

Primary outcome [2]

Maternal lifestyle behaviour change (LBC) as assessed by decrease in weight (4kg or more) measured by research staff using digital scales.

Timepoint [2]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values).

Primary outcome [3]

Maternal lifestyle behaviour change (LBC) as assessed by a decrease in waist circumference (2cm or more) measured with a measuring tape around the narrowest part of the torso.

Timepoint [3]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values).

Secondary outcome [1]

Lifestyle behaviour change measures assessed by the self-reported NSW Population Health survey questions

Timepoint [1]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values)

Secondary outcome [2]

Change in average blood pressure measured using the average of three measurements from a validated automated blood pressure device; the Omron HEM-907

.

Timepoint [2]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values).

Secondary outcome [3]

Infant measures recorded in 'My Personal Health Record' (Blue Book): weight.

Timepoint [3]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values).

Secondary outcome [4]

Maternal serological measures assessed by measuring CRP.

Timepoint [4]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values)

Secondary outcome [5]

Maternal vascular function measures: central arterial pressure using SphygmoCor applanation tanometry,

Timepoint [5]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values).

Secondary outcome [6]

Economic analysis
A cost-effectiveness analysis from the perspective of the healthcare system will be undertaken alongside the RCT. The primary economic outcome will be the incremental cost per case of BP and weight/waist circumference reduction achieved in Groups 2 and 3 during the study time period.

Timepoint [6]

At 12 months postpartum

Secondary outcome [7]

Women’s satisfaction with care measured using the self reported experience measure (PREM) incorporating elements of the Adherence to a Healthy Lifestyle, Burden of Treatment, and CSQ-8 Client Satisfaction Questionnaire.

Timepoint [7]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values)

Secondary outcome [8]

Change in weight. Weight measured by researcher using digital scales

Timepoint [8]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values)

Secondary outcome [9]

Change in waist circumference. Waist circumference measured by researcher using measuring tape around the narrowest part of the participant's torso.

Timepoint [9]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values)

Secondary outcome [10]

Infant measures recorded in 'My Personal Health Record' (Blue Book): height.

Timepoint [10]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values)

Secondary outcome [11]

Infant measures recorded in 'My Personal Health Record' (Blue Book): head circumference

Timepoint [11]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values)

Secondary outcome [12]

Infant measures recorded in 'My Personal Health Record' (Blue Book): abdominal circumference

Timepoint [12]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values)

Secondary outcome [13]

Maternal serological measures assessed by measuring fasting insulin/glucose.

Timepoint [13]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values)

Secondary outcome [14]

Maternal serological measures assessed by measuring fasting cholesterol/triglyceride.

Timepoint [14]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values)

Secondary outcome [15]

Maternal serological measures assessed by measuring liver function.

Timepoint [15]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values)

Secondary outcome [16]

Maternal serological measures assessed by measuring haemoglobin.

Timepoint [16]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values)

Secondary outcome [17]

Maternal serological measures assessed by measuring platelets.

Timepoint [17]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values)

Secondary outcome [18]

Maternal urine measures assessed by measuring eGFR

Timepoint [18]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values)

Secondary outcome [19]

Maternal urine measures assessed by measuring albumin:creatinine ratio.

Timepoint [19]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values)

Secondary outcome [20]

Maternal vascular function measure: pulse wave velocity using SphygmoCor applanation tanometry,

Timepoint [20]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values)

Secondary outcome [21]

Maternal vascular function measure: augmentation index using SphygmoCor applanation tanometry,

Timepoint [21]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values)

Secondary outcome [22]

Maternal vascular function measure performed using blood inflammatory cytokines

Timepoint [22]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values)

Secondary outcome [23]

Women’s satisfaction with care: a qualitative study to explore women’s experience of each aspect of the interventions. Semi structured interviews will be conducted with women from all groups between the 6 and 12 month visits. These interviews will explore the barriers and enablers to adopting healthy eating and physical activity behaviours post-partum and women will be asked their views of the intervention to better understand their engagement. All women will be invited to participate via a question at the end of the women’s 6 month survey and we will purposefully sample from each of the groups to ensure that views are captured about each arm of the intervention. Each interview will be digitally recorded (audio only) and later transcribed verbatim in preparation for a thematic analysis.

Timepoint [23]

At 12 months postpartum

Secondary outcome [24]

Maternal vascular function measure: an ultrasound of the carotid arteries

Timepoint [24]

At 12 months postpartum (comparison between 6 month and 12 months postpartum values)

Eligibility

Key inclusion criteria

Have given birth at one of the study hospitals during the study period.
The index pregnancy was complicated by a hypertensive disorder of pregnancy: preeclampsia (PE), gestational hypertension (GH), chronic hypertension ± superimposed PE

Minimum age

18 Years

Maximum age

No limit

Sex

Females

Can healthy volunteers participate?

Key exclusion criteria

Plan to move out of study area/known unavailability to follow-up during study period
Active severe mental health condition or developmental disability precluding informed consent.

Study design

Purpose of the study

Prevention

Allocation to intervention

Randomised controlled trial

Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)

Participants will be randomised using REDCap software. Researchers at each of the study sites will have access to REDCap for randomisation and data entry of study participants (but not access to the randomisation block details). Allocation concealment is ensured, as the randomisation code will not be released until after baseline questionnaires have been completed and the study researcher then accesses REDCap for randomisation to Group 1, 2 or 3.

Methods used to generate the sequence in which subjects will be randomised (sequence generation)

Participants will be randomly assigned to Group 1, 2 or 3 with a 1:1:1 allocation as per a computer generated randomisation schedule. Randomisation will be stratified by site, parity (1 versus >1) and body mass index (<30 versus 30+), using blocks. The block sizes will not be disclosed, to ensure concealment. Details relating to block randomisation will be kept in a separate document not available to anyone who is involved in trial recruitment.

Masking / blinding

Open (masking not used)

Who is / are masked / blinded?

Intervention assignment

Parallel

Other design features

Due to the nature of the intervention, neither postpartum clinic staff nor participants can be blinded to allocation.

Phase

Not Applicable

Type of endpoint/s

Efficacy

Statistical methods / analysis

There are six primary hypotheses resulting from an all-pairwise comparison of the three study groups (two intervention groups and control) in the two primary outcomes of 1) maternal systolic BP 2) binary threshold on maternal weight and/or waist circumference change from 6-12 months postpartum.
The three primary hypotheses relating to primary outcome 1 (BP) will be incorporated into an ANOVA model, with those relating to outcome 2 (composite measure) into a logistic regression model. The model fit statistics (F-test and t-test) from each of the models will be used to determine (with a threshold of alpha = 0.05) whether the relevant elementary hypotheses should be evaluated. If the threshold is met, the R package multcomp, will be used in order to test the relevant elementary hypothesis while controlling the familywise type I error rate at alpha = 0.05.

This approach allows simultaneous inferences to be made over both parametric models and all relevant hypotheses, while accounting for correlation between the test statistics and allowing for stepwise testing procedures. All (three or six) tests that pass to the second stage of testing will be considered to be one family of tests and tested as two-sided and based on a null hypothesis of no treatment effect. A multiplicity adjusted p-value of less than 0.05 will be considered significant in any of the tests for the primary outcomes.

Recruitment

Recruitment status

Completed

Date of first participant enrolment

Anticipated

21/01/2019

Actual

21/01/2019

Date of last participant enrolment

Anticipated

30/06/2022

Actual

27/07/2022

Date of last data collection

Anticipated

31/08/2022

Actual

24/08/2022

Sample size

Target

480

Accrual to date

Final

484

Recruitment in Australia

Recruitment state(s)

NSW

Recruitment hospital [1]

St George Hospital - Kogarah

Recruitment hospital [2]

Royal Hospital for Women - Randwick

Recruitment hospital [3]

Royal Prince Alfred Hospital - Camperdown

Recruitment hospital [4]

Campbelltown Hospital - Campbelltown

Recruitment hospital [5]

Liverpool Hospital - Liverpool

Recruitment hospital [6]

Westmead Hospital - Westmead

Recruitment postcode(s) [1]

2217 - Kogarah

Recruitment postcode(s) [2]

2031 - Randwick

Recruitment postcode(s) [3]

2050 - Camperdown

Recruitment postcode(s) [4]

2560 - Campbelltown

Recruitment postcode(s) [5]

2170 - Liverpool

Recruitment postcode(s) [6]

2145 - Westmead

Funding & Sponsors

Funding source category [1]

Government body

Name [1]

New South Wales Department of Health Translational Research Grants Scheme

Address [1]

NSW Ministry of Health
Office for Health and Medical Research
73 Miller Street
North Sydney NSW 2060

Country [1]

Australia

Primary sponsor type

Individual

Name

Dr Amanda Henry

Address

Department of Women's and Children's Health
Level 2
Prichard Wing
St George Hospital
Gray Street
Kogarah NSW 2217

Country

Australia

Secondary sponsor category [1]

Individual

Name [1]

Professor Mark Brown

Address [1]

Division of Medicine
St George Hospital
Gray Street
Kogarah NSW 2217

Country [1]

Australia

Ethics approval

Ethics application status

Approved

Ethics committee name [1]

South Eastern Sydney Local Health District Human Research Ethics Committee

Ethics committee address [1]

Room G71 east Wing
Edmund Blacket Building
Prince of Wales Hospital
Randwick NSW 2031

Ethics committee country [1]

Australia

Date submitted for ethics approval [1]

28/08/2018

Approval date [1]

25/10/2018

Ethics approval number [1]

18/193 (HREC/18/POWH/401)

Summary

Brief summary

Hypertensive disorders of pregnancy (HDP) complicate 1 in 10 Australian pregnancies, and are associated with an increased medium to long term risk of cardiovascular disease and death, including heart attacks and stroke. However, few initiatives currently target women after HDP to improve their long term health.
This multicentre study will assess outcomes of 3 interventions in women being managed after an HDP pregnancy:
A. Optimised usual care (CONTROL): Follow-up in primary healthcare and supplied written information
B. Brief Education Intervention: One-off individualised risk assessment and education “Brief Intervention” at a specialised hospital postpartum clinic
C. Extended Lifestyle Intervention: an individualised “Extended Intervention” comprising a 6 month healthy lifestyle program, commencing six months postpartum
480 women will be randomised to one of the 3 interventions 6 months after HDP, with outcome assessment at 12 months (and plan for 2 and 3 year follow-through assessment). Outcomes:
1) Lifestyle behaviour and/or blood pressure (BP) change
2) Cost-effectiveness and patient acceptability
3) Infant growth trajectory
4) Non-invasive maternal measures of vascular structure and function

Trial website

Trial related presentations / publications

Public notes

Contacts

Principal investigator

Name

A/Prof Amanda Henry

Address

Department of Women's and Children's Health
Level 2
Prichard Wing
St George Hospital
gray Street
Hogarth NSW 2217

Country

Australia

Phone

+612 91132315

Fax

+612 91133901

[email protected]

Contact person for public queries

Name

Dr Lynne Roberts

Address

1 South maternity
St George Hospital
Gray Street
Kogarah NSW 2217

Country

Australia

Phone

+612 91132117

Fax

+612 91133642

[email protected]

Contact person for scientific queries

Name

A/Prof Amanda Henry

Address

Department of Women's and children's Health
Level 2
Prichard Wing
St George Hospital
gray Street
Hogarth NSW 2217

Country

Australia

Phone

+612 91132315

Fax

+612 91133901

[email protected]

Data sharing statement

Will individual participant data (IPD) for this trial be available (including data dictionaries)?

Yes

What data in particular will be shared?

All of the individual participant data collected during the trial, after de-identification, will be available for use in future IPD meta-analysis with national and international colleagues who may perform intervention trials for women after hypertensive pregnancy.

When will data be available (start and end dates)?

Beginning 6 months after publication of trial results, no end date.

Available to whom?

Case by case basis at the discretion of the primary sponsor.

Available for what types of analyses?

Data will be available to achieve the aims in the approved proposal, and for IPD meta-analyses.

How or where can data be obtained?

Access subject to approval by Principal Investigator

What supporting documents are/will be available?

Doc. No.	Type	Citation	Link	Email	Other Details	Attachment
455	Informed consent form			[email protected]	Current PISCF available from ANZCTR site	376286-(Uploaded-01-06-2022-11-07-05)-Study-related document.doc
456	Ethical approval			[email protected]	Ethics approval letter available from ANZCTR site	376286-(Uploaded-23-11-2018-12-05-55)-Study-related document.pdf

Results publications and other study-related documents

Documents added manually

No documents have been uploaded by study researchers.

Documents added automatically

Source	Title	Year of Publication	DOI
Embase	The Association between Nutrition, Physical Activity, and Cardiometabolic Health at 6 Months following a Hypertensive Pregnancy: A BP2 Sub-Study.	2023	https://dx.doi.org/10.3390/nu15153294

N.B. These documents automatically identified may not have been verified by the study sponsor.

Trial Review

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