Optimising the monitoring and management of raised blood pressure including proteinuria testing during pregnancy: the BUMP research programme including 2 RCTs

BackgroundRaised blood pressure affects 10% of pregnancies worldwide, of which around half develop pre-eclampsia including proteinuria, causing maternal and perinatal morbidity and mortality.ObjectivesTo develop and test interventions for self-monitoring of blood pressure designed to improve the detection and management of hypertension in pregnancy. Additionally, to test the accuracy of self-testing of urine for protein, a key marker of pre-eclampsia.Design and methodsDevelopment phase, a pilot trial, two large randomised controlled trials of self-monitoring of blood pressure interventions with integrated economic evaluations, linked qualitative work, a large survey and a diagnostic accuracy study of self-testing for proteinuria, and finally economic modelling.Setting and participantsAntenatal clinics in 16 English hospitals. Participants were pregnant women and antenatal healthcare professionals.Patient and public involvementComprehensive involvement from initial development through to dissemination, with collaboration from both individuals and relevant charities and organisations.InterventionsSelf-monitoring of blood pressure supported by app to improve the detection (BUMP1) and management (BUMP2) of raised blood pressure in pregnancy (WS3.2.1 and 2). Proteinuria self-testing by pregnant hypertensive women (UDIP, WS4).Main outcome measuresQualitative data informed the development of the BUMP App and trial (WS1). Feasibility of self-monitoring of blood pressure in hypertensive pregnancy (recruitment, retention, adherence and intervention persistence) (WS2). Prevalence of self-monitoring of blood pressure during pregnancy (WS3.1). Time to diagnosis of hypertension defined in routinely recorded clinical data (BUMP1, WS3.2.1) and difference in mean systolic blood pressure recorded by healthcare professionals between randomisation and birth (BUMP2, WS3.2.2). WS3.3 and 4.2 evaluated experiences with the trial and UDIP respectively using inductive and deductive thematic analysis. Within-trial cost–consequence analysis and long-term cost-effectiveness modelling (WS3.4 and WS5). Proteinuria testing accuracy (WS4.1).ResultsWS1: Areas important to staff included providing clear patient information and supporting them in decision-making in the context of discrepant readings. The intervention was optimised iteratively with pregnant women. WS2: A feasibility trial showed that the self-monitoring of blood pressure intervention was feasible and acceptable. WS3.1: Data from a survey of 5181 women showed that 19% of pregnant women were currently self-monitoring blood pressure but only 482/983 (49%) shared this information with healthcare professionals. WS3.2.1: Self-monitoring of blood pressure in addition to usual care did not lead to an earlier diagnosis of clinic hypertension in routinely recorded clinical data with no evidence of differences in maternal or perinatal outcomes or serious adverse events (BUMP1). WS3.2.2: Self-monitoring of blood pressure in pregnancy hypertension did not improve clinic blood pressure control, with no difference in maternal or perinatal outcomes or serious adverse events (BUMP2). WS3.3: Self-monitoring was generally accepted by women and professionals with differences in views of which blood pressure data to give precedence. Women found self-monitoring empowering, provided health professionals considered home readings in their management. On occasion self-monitoring proved unsettling due to uncertainty. WS3.4: Within trial economic analyses revealed no significant difference in overall total costs between trial arms in either BUMP1 or BUMP2. Women’s health-related quality of life (EQ-5D-5L) was similar between groups in both trials. WS4: Self-testing for proteinuria had a sensitivity of 0.71 (95% confidence interval 0.62 to 0.79) and a specificity of 0.89 (95% confidence interval 0.84 to 0.92) compared to laboratory protein–creatinine ratio testing and this was not clinically or statistically different when compared to healthcare professionals or a colorimetric monitor (UDIP, WS4.1). Self-testing was generally acceptable (WS4.2). WS5: Model frameworks capable of facilitating exploration of the long-term cost-effectiveness of combining self-monitoring of blood pressure with blood pressure treatment and management policies were developed for use in future research projects in the area. Implementation: Self-monitoring was rapidly and widely implemented during the pandemic but has yet to become fully embedded in clinical pathways.LimitationsSelf-monitoring of blood pressure by women in the control groups; difficulties in testing self-monitoring of blood pressure in clinical pathways in the absence of evidence or accepted treatment thresholds; process evaluation suggested women and professionals privileged different information.ConclusionsSelf-monitoring of blood pressure during higher risk or hypertensive pregnancy was feasible, acceptable, safe, and no more expensive, but did not improve the detection of hypertension or blood pressure control in those with hypertension when used alongside usual care. During the programme, self-monitoring of blood pressure entered common practice in pregnancy, a process accelerated by the pandemic. Pregnant women can read a dipstick for urinary protein with similar accuracy to healthcare professionals or colorimetric testing, and find this acceptable, suggesting that self-testing could be included in clinical pathways.Future workFuture trials of interventions including self-monitoring of blood pressure should test strategies in the context of novel clinical pathways.Study registrationThis study is registered as Current Controlled Trials ISRCTN16018898.FundingThis award was funded by the National Institute for Health and Care Research (NIHR) Programme Grants for Applied Research programme (NIHR award ref.: RP-PG-0614-20005) and is published in full in Programme Grants for Applied Research; Vol. 14, No. 3. See the NIHR Funding and Awards website for further award information.