Research priorities for pregnancy hypertension: a UK priority setting partnership with the James Lind Alliance

Pharmacotherapeutic options for the treatment of hypertension in pregnancy

INTRODUCTION

Hypertensive disorders of pregnancy affect approximately one in 10 pregnancies and are associated with increased risk of adverse fetal, neonatal and maternal outcomes. There is strong evidence that effective treatment of hypertension (blood pressure ≥ 140/90 mmHg), and enhanced monitoring throughout pregnancy reduces these risks.

AREAS COVERED

This article provides a contemporaneous review of treatment of hypertension in pregnancy with antihypertensive agents. We completed a systematic search and review of all meta-analyses and systematic reviews of studies comparing antihypertensives for treatment of pregnancy hypertension in the last five years. We provide a clinically focused summary of when to treat hypertension in pregnancy and which antihypertensive agents can be offered. Special scenarios reviewed include treatment-resistant hypertension and pre-pregnancy antihypertensive optimization.

EXPERT OPINION

Several antihypertensives are considered safe and are known to be effective for treatment of hypertension in pregnancy. Given the current uncertainty as to which antihypertensive(s) are superior for treatment of hypertension in pregnancy, women should be counselled and offered a range of antihypertensive options in keeping with evidence on clinical effectiveness, local context and availability of antihypertensive(s), potential side effect profile, and women's preference. Further research is required to help guide clinical decision making, and move toward personalized treatment.

National priority setting partnership using a Delphi consensus process to develop neonatal research questions suitable for practice-changing randomised trials in the UK

BACKGROUND

The provision of neonatal care is variable and commonly lacks adequate evidence base; strategic development of methodologically robust clinical trials is needed to improve outcomes and maximise research resources. Historically, neonatal research topics have been selected by researchers; prioritisation processes involving wider stakeholder groups have generally identified research themes rather than specific questions amenable to interventional trials.

OBJECTIVE

To involve stakeholders including parents, healthcare professionals and researchers to identify and prioritise research questions suitable for answering in neonatal interventional trials in the UK.

DESIGN

Research questions were submitted by stakeholders in population, intervention, comparison, outcome format through an online platform. Questions were reviewed by a representative steering group; duplicates and previously answered questions were removed. Eligible questions were entered into a three-round online Delphi survey for prioritisation by all stakeholder groups.

PARTICIPANTS

One hundred and eight respondents submitted research questions for consideration; 144 participants completed round one of the Delphi survey, 106 completed all three rounds.

RESULTS

Two hundred and sixty-five research questions were submitted and after steering group review, 186 entered into the Delphi survey. The top five ranked research questions related to breast milk fortification, intact cord resuscitation, timing of surgical intervention in necrotising enterocolitis, therapeutic hypothermia for mild hypoxic ischaemic encephalopathy and non-invasive respiratory support.

CONCLUSIONS

We have identified and prioritised research questions suitable for practice-changing interventional trials in neonatal medicine in the UK at the present time. Trials targeting these uncertainties have potential to reduce research waste and improve neonatal care.

Altered Oral Nitrate Reduction and Bacterial Profiles in Hypertensive Women Predict Blood Pressure Lowering Following Acute Dietary Nitrate Supplementation

BACKGROUND

The efficacy of dietary nitrate supplementation to lower blood pressure (BP) in pregnant women is highly variable. We aimed to investigate whether differences in oral microbiota profiles and oral nitrate-reducing capacity may explain interindividual differences in BP lowering following nitrate supplementation.

METHODS

Participants recruited for this study were both pregnant and nonpregnant women, with or without hypertension (n=55). Following an overnight fast, plasma, saliva, and tongue scraping samples were collected for measurement of nitrate/nitrite concentrations, oral NaR (nitrate reductase) activity, and microbiota profiling using 16S rRNA gene sequencing. Baseline BP was measured, followed by the administration of a single dose of dietary nitrate (400 mg nitrate in 70 mL beetroot juice). Post-nitrate intervention, plasma and salivary nitrate/nitrite concentrations and BP were determined 2.5 hours later.

RESULTS

Women with hypertension had significantly lower salivary nitrite concentrations (P=0.006) and reduced abundance of the nitrate-reducing taxa Veillonella(P=0.007) compared with normotensive women. Oral NaR activity was not significantly different in pregnant versus nonpregnant women (P=0.991) but tended to be lower in hypertensive compared with normotensive women (P=0.099). Oral NaR activity was associated with both baseline diastolic BP (P=0.050) and change in diastolic BP following acute nitrate intake (P=0.01, adjusted for baseline BP).

CONCLUSIONS

The abundance and activity of oral nitrate-reducing bacteria impact both baseline BP as well as the ability of dietary nitrate supplementation to lower BP. Strategies to increase oral nitrate-reducing capacity could lower BP and enhance the efficacy of dietary nitrate supplementation, in pregnancy as well as in nonpregnant adults.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT03930693.

Research priorities for maternal and perinatal health clinical trials and methods used to identify them: A systematic review

OBJECTIVE

Research prioritisation helps to target research resources to the most pressing health and healthcare needs of a population. This systematic review aimed to report research priorities in maternal and perinatal health and to assess the methods that were used to identify them.

METHODS

A systematic review was undertaken. Projects that aimed to identify research priorities that were considered to be amenable to clinical trials research were eligible for inclusion. The search, limited to the last decade and publications in English, included MEDLINE, EMBASE, CINHAL, relevant Cochrane priority lists, Cochrane Priority Setting Methods Group homepage, James Lind Alliance homepage, Joanna Brigg's register, PROSPERO register, reference lists of all included articles, grey literature, and the websites of relevant professional bodies, until 13 October 2020. The methods used for prioritisation were appraised using the Reporting Guideline for Priority Setting of Health Research (REPRISE).

FINDINGS

From the 62 included projects, 757 research priorities of relevance to maternal and perinatal health were identified. The most common priorities related to healthcare systems and services, pregnancy care and complications, and newborn care and complications. The least common priorities related to preconception and postpartum health, maternal mental health, contraception and pregnancy termination, and fetal medicine and surveillance. The most commonly used prioritisation methods were Delphi (20, 32%), Child Health Nutrition Research Initiative (17, 27%) and the James Lind Alliance (10, 16%). The fourteen projects (23%) that reported on at least 80% of the items included in the REPRISE guideline all used an established research prioritisation method.

CONCLUSIONS

There are a large number of diverse research priorities in maternal and perinatal health that are amenable to future clinical trials research. These have been identified by a variety of research prioritisation methods.

Cross-sectional diagnostic accuracy study of self-testing for proteinuria during hypertensive pregnancies: The UDIP study

OBJECTIVE

To determine the accuracy of self-testing for proteinuria during pregnancy.

DESIGN

Diagnostic accuracy study.

SETTING

Antenatal clinics, maternity assessment units and inpatient wards at three hospital sites.

POPULATION OR SAMPLE

345 pregnant women.

METHODS

Pregnant women self-tested in-clinic for urinary protein using visually read dipsticks with samples then sent for laboratory estimation of the spot protein-creatinine ratio (PCR) (primary reference test). Secondary index tests included testing by antenatal healthcare professionals and an automated colorimetric reader.

MAIN OUTCOME MEASURES

Sensitivity, specificity, negative predictive value, positive predictive value and likelihood ratios were calculated for self-testing (primary index test) along with healthcare professional and colorimetric testing compared to the primary reference test (PCR).

RESULTS

335/345 (97%) had sufficient data to be included in the analysis. Self-testing had a sensitivity of 0.71 (95% confidence interval [CI] 0.62-0.79) and a specificity of 0.89 (95% CI 0.84-0.92) compared to PCR. Sensitivity and specificity of testing by healthcare professionals and the colorimetric reader were similar: sensitivity 0.73 (95% CI 0.64-0.80) and 0.78 (95% CI 0.69-0.85), respectively; specificity 0.88 (95% CI 0.82-0.92) and 0.83 (95% CI 0.78-0.88), respectively.

CONCLUSION

Pregnant women can visually read a dipstick for urinary protein with similar accuracy to antenatal healthcare professionals. Automated colorimetric testing was not significantly different, in contrast to some previous studies. Self-testing has the potential to form part of a self-monitoring regime in pregnancy.

Calcium for pre-eclampsia prevention: A systematic review and network meta-analysis to guide personalised antenatal care

BACKGROUND

Calcium supplementation reduces the risk of pre-eclampsia, but questions remain about the dosage to prescribe and who would benefit most.

OBJECTIVES

To evaluate the effectiveness of high (≥1 g/day) and low (<1 g/day) calcium dosing for pre-eclampsia prevention, according to baseline dietary calcium, pre-eclampsia risk and co-interventions, and intervention timing.

SEARCH STRATEGY

CENTRAL, PubMed, Global Index Medicus and CINAHL, from inception to 2 February 2021, clinical trial registries, reference lists and expert input (CRD42018111239).

SELECTION CRITERIA

Randomised controlled trials of calcium supplementation for pre-eclampsia prevention, for women before or during pregnancy. Network meta-analysis (NMA) also included trials of different calcium doses.

DATA COLLECTION AND ANALYSIS

Two independent reviewers extracted published data. The meta-analysis employed random-effects models and the NMA, a Bayesian random-effects model, to obtain direct and indirect effect estimates.

MAIN RESULTS

The meta-analysis included 30 trials (N = 20 445 women), and the NMA to evaluate calcium dosage included 25 trials (N = 15 038). Calcium supplementation prevented pre-eclampsia similarly with a high dose (RR 0.49, 95% CI 0.36-0.66) or a low dose (RR 0.49, 95% CI 0.36-0.65). By NMA, high-dose (vs low-dose) calcium did not differ in effect (RR 0.79, 95% CI 0.43-1.40). Calcium was similarly effective regardless of baseline pre-eclampsia risk, vitamin D co-administration or timing of calcium initiation, but calcium was ineffective among women with adequate average baseline calcium intake.

CONCLUSIONS

Low- and high-dose calcium supplementation are effective for pre-eclampsia prevention in women with low calcium intake. This has implications for population-level implementation where dietary calcium is low, and targeted implementation where average intake is adequate.

TWEETABLE ABSTRACT

A network meta-analysis of 25 trials found that low-dose calcium supplementation (<1 g/day) is as effective as high-dose calcium supplementation (≥1 g/day) in halving the risk of pre-eclampsia when baseline calcium intake is low.

National priority setting partnership using a Delphi consensus process to develop neonatal research questions suitable for practice-changing randomised trials in the United Kingdom

INTRODUCTION

Methodologically robust clinical trials are required to improve neonatal care and reduce unwanted variations in practice. Previous neonatal research prioritisation processes have identified important research themes rather than specific research questions amenable to clinical trials. Practice-changing trials require well-defined research questions, commonly organised using the Population, Intervention, Comparison, Outcome (PICO) structure. By narrowing the scope of research priorities to those which can be answered in clinical trials and by involving a wide range of different stakeholders, we aim to provide a robust and transparent process to identify and prioritise research questions answerable within the National Healthcare System to inform future practice-changing clinical trials.

METHODS AND ANALYSIS

A steering group comprising parents, doctors, nurses, allied health professionals, researchers and representatives from key organisations (Neonatal Society, British Association of Perinatal Medicine, Neonatal Nurses Association and Royal College of Paediatrics and Child Health) was identified to oversee this project. We will invite submissions of research questions formatted using the PICO structure from the following stakeholder groups using an online questionnaire: parents, patients, healthcare professionals and academic researchers. Unanswered, non-duplicate research questions will be entered into a three-round eDelphi survey of all stakeholder groups. Research questions will be ranked by mean aggregate scores.

ETHICS AND DISSEMINATION

The final list of prioritised research questions will be disseminated through traditional academic channels, directly to key stakeholder groups through representative organisations and on social media. The outcome of the project will be shared with key research organisations such as the National Institute for Health Research. Research ethics committee approval is not required.

Postnatal health and care following hypertensive disorders in pregnancy: a prospective cohort study (BPiPP study)

Introduction

One in 10 women have hypertensive disorders in pregnancy (HDP) and are at risk of adverse short- and long-term health outcomes, yet there is limited information on their postnatal health and care needs. This study aimed to look at postnatal physical and psychological morbidity in women with HDP, compared to women without HDP, and the postnatal care received in both groups.

Methods

Within a prospective cohort study, women with and without HDP were identified and recruited on the postnatal ward of 17 maternity units across England and invited to complete a short baseline questionnaire. At 3 months postpartum, women were sent a follow-up questionnaire, with reminders. The principal outcomes were the mean score at 3 months for the Edinburgh Postnatal Depression Scale (EPDS) and the EuroQol Group 5-dimension (EQ-5D) scale.

Results

One thousand eight hundred twenty-nine women agreed to participate. Of these, 1757 (96%) completed the baseline questionnaire: 769 (44%) women had HDP and 988 (56%) women did not. Despite a difference in health-related quality of life and symptoms of depression at baseline between the two groups, at 3 months postnatal, within the 653 women who completed their follow-up questionnaire (37.2% of those who completed the baseline questionnaire) there were no significant differences between the groups (median EQ-5D VAS: 85 in women with HDP, 85 in women without HDP, p = 0.99 and mean EPDS score 5.5 in women with HDP, 5.0 in women without HDP, p = 0.80). Overall levels of physical postnatal morbidity were high, with 89% reporting one or more morbidities. Approximately 9% of women were re-admitted within 3 months after birth, higher in the HDP group (13.1%) higher compared to women without HDP (5.5%; RR 2.41; 95% CI 1.44–4.05).

Conclusion

Overall levels of physical and psychological morbidity were high in this postnatal population. Although there were increased needs of women with HDP in the immediate postnatal period (compared to other women), their health assessments were similar at 3 months. This study highlights the unmet needs of women in the postnatal period, in addition to a missed opportunity to influence future pregnancies and improve the longer-term health of women and their babies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-04540-2.

Oral Antihypertensives for Nonsevere Pregnancy Hypertension: Systematic Review, Network Meta- and Trial Sequential Analyses

BACKGROUND

We aimed to address which antihypertensives are superior to placebo/no therapy or another antihypertensive for controlling nonsevere pregnancy hypertension and provide future sample size estimates for definitive evidence.

METHODS

Randomized trials of antihypertensives for nonsevere pregnancy hypertension were identified from online electronic databases, to February 28, 2021 (registration URL: https://www.crd.york.ac.uk/PROSPERO/; unique identifier: CRD42020188725). Our outcomes were severe hypertension, proteinuria/preeclampsia, fetal/newborn death, small-for-gestational age infants, preterm birth, and admission to neonatal care. A Bayesian random-effects model generated estimates of direct and indirect treatment comparisons. Trial sequential analysis informed future trials needed.

RESULTS

Of 1246 publications identified, 72 trials were included; 61 (6923 women) were informative. All commonly prescribed antihypertensives (labetalol, other β-blockers, methyldopa, calcium channel blockers, and mixed/multi-drug therapy) versus placebo/no therapy reduced the risk of severe hypertension by 30% to 70%. Labetalol decreased proteinuria/preeclampsia (odds ratio, 0.73 [95% credible interval, 0.54-0.99]) and fetal/newborn death (odds ratio, 0.54 [0.30-0.98]) compared with placebo/no therapy, and proteinuria/preeclampsia compared with methyldopa (odds ratio, 0.66 [0.44-0.99]) and calcium channel blockers (odds ratio, 0.63 [0.41-0.96]). No other differences were identified, but credible intervals were wide. Trial sequential analysis indicated that 2500 to 10 000 women/arm (severe hypertension or safety outcomes) to >15 000/arm (fetal/newborn death) would be required to provide definitive evidence.

CONCLUSIONS

In summary, all commonly prescribed antihypertensives in pregnancy reduce the risk of severe hypertension, but labetalol may also decrease proteinuria/preeclampsia and fetal/newborn death. Evidence is lacking for many other safety outcomes. Prohibitive sample sizes are required for definitive evidence. Real-world data are needed to individualize care.

Assessing Australian women's knowledge and knowledge preferences about long-term health after hypertensive disorders of pregnancy: a survey study

OBJECTIVES

To (1) assess women's current knowledge regarding long-term cardiovascular health after hypertensive disorders of pregnancy (2) elicit women's preferred educational content and format regarding health after hypertensive disorders of pregnancy.

DESIGN AND SETTING

A custom-created online survey exploring Australian women's knowledge about long-term health after hypertensive disorders of pregnancy, distributed through consumer groups and social media.

PARTICIPANTS

266 women with (n=174) or without (n=92) a history of hypertensive disorders of pregnancy. PRIMARY AND SECONDARY OUTCOME MEASURES: (1) Proportion of women identifying long-term health risks after hypertensive disorder of pregnancy using a 10-point risk knowledge score with 0-4 'low', 4.1-7.0 'moderate' and 7.1-10 'high'. (2) Exploration of preferred content, format and distribution of educational material post hypertensive disorder of pregnancy.

RESULTS

Knowledge scores about health after hypertensive disorder of pregnancy were moderate in groups with and without a history of the disorder. Knowledge was highest regarding risk of recurrent hypertensive disorders in a subsequent pregnancy, 'moderate' for chronic hypertension and heart attack, 'moderate' and 'low' regarding risk of heart disease and 'low' for diabetes and renal disease. Only 36% of all participants were aware that risks start within 10 years after the affected pregnancy. The majority of respondents with a history of hypertensive disorder of pregnancy (76%) preferred receiving information about long-term health 0-6 months post partum from a healthcare provider (80%), key organisations (60%), social media (47%) and brochures/flyers (43%).

CONCLUSIONS

Women's knowledge regarding health risks after hypertensive disorder of pregnancy was 'moderate', although with important disease-specific gaps such as increased risk of diabetes. Most women wanted to be informed about their long-term health from a healthcare provider.