Women's views and postpartum follow-up in the CHIPS Trial (Control of Hypertension in Pregnancy Study)

Perceptions and experiences of blood pressure self-monitoring during hypertensive pregnancy: A qualitative analysis of women's and clinicians' experiences in the OPTIMUM-BP trial

BACKGROUND

Self-monitoring of blood pressure (BP) has been shown to be effective at improving BP control in the general population. The OPTIMUM-BP feasibility study was a prospective randomised controlled trial of self-monitoring of BP (SMBP) during hypertensive pregnancy.

OBJECTIVE

To explore experiences, perceptions, and use of the OPTIMUM-BP self-monitoring intervention.

STUDY DESIGN

Qualitative study within the OPTIMUM-BP feasibility trial. Semi-structured interviews with a purposive sample of pregnant women with chronic hypertension (n = 24) and their clinicians (n = 8) as well as 38 ethnographic observations of antenatal visits.

RESULTS

Women found self-monitoring of BP feasible and acceptable and were highly motivated and pro-active in their monitoring, reporting greater control and knowledge of BP and reassurance. Women's persistence with SMBP was driven by a perceived need to safeguard the pregnancy, particularly among those taking antihypertensive medication. Clinicians also described the intervention as acceptable, though BP variability could cause uncertainty. Clinicians used different heuristics to integrate home and clinic readings. Observations suggested close working relationships between women and clinicians were key for confident integration of self-monitoring.

CONCLUSIONS

Self-monitoring of BP was acceptable both to pregnant women with hypertension and their clinicians. More research is needed to understand BP variability within pregnancy to help interpret and integrate home BP readings for improved BP management. Clinical pathways that use BP self-monitoring should aim to maintain the continuity of care and relationships that are valued and appear pivotal for the confident and safe use of self-monitoring in pregnancy.

Toward personalized management of chronic hypertension in pregnancy

Chronic hypertension complicates 1% to 2% of pregnancies, and it is increasingly common. Women with chronic hypertension are an easily recognized group who are in touch with a wide variety of healthcare providers before, during, and after pregnancy, mandating that chronic hypertension in pregnancy be within the scope of many practitioners. We reviewed recent data on management to inform current care and future research. This study is a narrative review of published literature. Compared with normotensive women, women with chronic hypertension are at an increased risk of maternal and perinatal complications. Women with chronic hypertension who wish to be involved in their care can do by measuring blood pressure at home. Accurate devices for home blood pressure monitoring are now readily available. The diagnostic criteria for superimposed preeclampsia remain problematic because most guidelines continue to include deteriorating blood pressure control in the definition. It has not been established how angiogenic markers may aid in confirmation of the diagnosis of superimposed preeclampsia when suspected, over and above information provided by routinely available clinical data and laboratory results. Although chronic hypertension is a strong risk factor for preeclampsia, and aspirin decreases preeclampsia risk, the effectiveness specifically among women with chronic hypertension has been questioned. It is unclear whether calcium has an independent effect in preeclampsia prevention in such women. Treating hypertension with antihypertensive therapy halves the risk of progression to severe hypertension, thrombocytopenia, and elevated liver enzymes, but a reduction in preeclampsia or serious maternal complications has not been observed; however, the lack of evidence for the latter is possibly owing to few events. In addition, treating chronic hypertension neither reduces nor increases fetal or newborn death or morbidity, regardless of the gestational age at which the antihypertensive treatment is started. Antihypertensive agents are not teratogenic, but there may be an increase in malformations associated with chronic hypertension itself. At present, blood pressure treatment targets used in clinics are the same as those used at home, although blood pressure values tend to be inconsistently lower at home among women with hypertension. Although starting all women on the same antihypertensive medication is usually effective in reducing blood pressure, it remains unclear whether there is an optimal agent for such an approach or how best to use combinations of antihypertensive medications. An alternative approach is to individualize care, using maternal characteristics and blood pressure features beyond blood pressure level (eg, variability) that are of prognostic value. Outcomes may be improved by timed birth between 38 0/7 and 39 6/7 weeks' gestation based on observational literature; of note, confirmatory trial evidence is pending. Postnatal care is facilitated by the acceptability of most antihypertensives (including angiotensin-converting enzymes inhibitors) for use in breastfeeding. The evidence base to guide the care of pregnant women with chronic hypertension is growing and aligning with international guidelines. Addressing outstanding research questions would inform personalized care of chronic hypertension in pregnancy.

[Pharmacological treatment of non-severe hypertension during pregnancy, postpartum and breastfeeding]

Hypertension (HTN) in pregnancy is defined as systolic blood pressure ≥ 140 and/or diastolic blood pressure ≥ 90 mmHg. Based on the values, it is classified as non-severe (< 160/110 mmHg) and severe (≥ 160/110 mmHg). Before starting treatment in non-severe HTN, white- coat HTN should be ruled out. If outpatient management is possible, pharmacological initiation is suggested with sustained high values, avoiding < 120/80 mmHg. Safe drugs during pregnancy are methyldopa, labetalol, and nifedipine-retard. The use of nifedipine-XL or amlodipine can be considered with a lower level of evidence of safety. Diuretics, atenolol, and other beta-blockers for antihypertensive purposes is not recommended in this period. Renin-angiotensin-aldosterone system inhibitors are strictly contraindicated. In postpartum and breastfeeding, the same therapeutic regimen used during pregnancy can be maintained, trying early withdrawal of methyldopa. During puerperium, amlodipine and enalapril are safe, with minimal excretion in breast milk.

Pre-eclampsia with severe features: management of antihypertensive therapy in the postpartum period

Introduction

there is variance in both the types and combinations of antihypertensive drugs used for managing pre-eclampsia in the postpartum period. Knowledge of the most common and suitable single or combination antihypertensive drug therapies in the postpartum period will minimize harmful effects, promote adherence to medications, overcome any fears that lactating mothers may have about these drugs and will assist in healthcare planning. Objective: to determine the types of antihypertensive drug therapies used in managing pre-eclampsia with severe features (sPE) in the postpartum period in a regional hospital in South Africa.

Methods

fifty consecutively presenting pregnant women with sPE were followed up prospectively from the pre-delivery period (within 48 hours before delivery) until day 3 postpartum. The antihypertensive drug therapies administered to the participants were observed. Their blood pressures were measured daily at 04: 00, 08: 00, 14: 00 and 22: 00 hours.

Results

nifedipine was the commonest rapid-acting agent used for severe hypertension. Prepartum, 9 different combinations of antihypertensive drugs were prescribed; alpha-methyldopa was the commonest single long-acting agent used. Postpartum, the number of different drug combinations administered were 15, 18, 22 and 16 on days 0, 1, 2 and 3 respectively. Alpha-methyldopa was the commonest single agent used on postpartum days 0 - 2 while hydrochlorothiazide was the most frequently used single agent on postpartum day 3. Postpartum, the commonest combination therapy was alpha-methyldopa and amlodipine on day 0; alpha-methyldopa and amlodipine as a regimen as well as alpha-methyldopa, amlodipine and hydrochlorothiazide as another regimen on day 1; alpha-methyldopa and amlodipine on day 2; and many amlodipine-based regimens on day 3.

Conclusion

a variety of antihypertensive drug combinations were used in the postpartum period indicating the need for standardised guidelines; however, detailed studies are required to evaluate their efficacies completely.

State-of-the-Art Diagnosis and Treatment of Hypertension in Pregnancy

Hypertension complicates up to 10% of pregnancies worldwide. Pregnancy hypertension is defined as systolic blood pressure (BP) equal to or greater than 140 mm Hg or diastolic BP equal to or greater than 90 mm Hg, usually on the basis of measurements in office/clinic settings and using various BP devices. Hypertensive disorders of pregnancy are classified into (1) chronic hypertension diagnosed before pregnancy or before 20 weeks' gestation, (2) gestational hypertension diagnosed at equal to or greater than 20 weeks, or (3) preeclampsia, defined restrictively as gestational hypertension with proteinuria or broadly as gestational hypertension with proteinuria or an end-organ manifestation consistent with preeclampsia. Absolute BP values equal to or greater than 140/90 mm Hg are associated with increased maternal and perinatal risks, particularly with preeclampsia. This review focuses on antihypertensive therapy of hypertensive disorders of pregnancy as a specific management strategy. Underpinning this therapy is the need for accurate measurement of BP, agreed-upon classification of pregnancy hypertension, agreed-upon BP thresholds for enhanced surveillance and antihypertensive treatment, and collaborative teamwork in management. Challenges relate to the methodology of studies on which care is based, as well as aspects of the care itself, particularly the unregulated use of home BP monitoring. Pitfalls include the unsubstantiated belief that nifedipine and magnesium sulfate cannot be used together and the perception that severe hypertension and nonsevere hypertension are separate entities rather than lying along a spectrum of BP values. The following must be addressed by future research: guidance for nuanced care as women transition between severe and nonsevere hypertension, personalized antihypertensive therapy, and incorporation of women's values into research priorities and clinical practice when antihypertensive care is chosen.