A randomized trial of tight vs. less tight control of mild essential and gestational hypertension in pregnancy

Perinatal Outcomes Associated With Management of Stage 1 Hypertension

OBJECTIVE

To evaluate the association between maternal blood pressure (BP) below 130/80 mm Hg compared with 130-139/80-89 mm Hg and pregnancy outcomes.

METHODS

We conducted a planned secondary analysis of CHAP (Chronic Hypertension and Pregnancy), an open label, multicenter, randomized controlled trial. Participants with mean BP below 140/90 mm Hg were grouped as below 130/80 mm Hg compared with 130-139/80-89 mm Hg by averaging postrandomization clinic BP throughout pregnancy. The primary composite outcome was preeclampsia with severe features, indicated preterm birth before 35 weeks of gestation, placental abruption, or fetal or neonatal death. The secondary outcome was small for gestational age (SGA).

RESULTS

Of 2,408 patients in CHAP, 2,096 met study criteria; 1,328 had mean BP 130-139/80-89 mm Hg and 768 had mean BP below 130/80 mm Hg. Participants with mean BP below 130/80 mm Hg were more likely to be older, on antihypertensive medication, in the active treatment arm, and to have lower BP at enrollment. Mean clinic BP below 130/80 mm Hg was associated with lower frequency of the primary outcome (16.0% vs 35.8%, adjusted relative risk 0.45; 95% CI 0.38-0.54) as well as lower risk of severe preeclampsia and indicated birth before 35 weeks of gestation. There was no association with SGA.

CONCLUSION

In pregnant patients with mild chronic hypertension, mean BP below 130/80 mm Hg was associated with improved pregnancy outcomes without increased risk of SGA.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov , NCT02299414.

Optimal blood pressure target to prevent severe hypertension in pregnancy: A systematic review and meta-analysis

Severe hypertension in pregnancy is a hypertensive crisis that requires urgent and intensive care due to its high maternal and fetal mortality. However, there is still a conflict of opinion on the recommendations of antihypertensive therapy. This study aimed to identify the optimal blood pressure (BP) levels to prevent severe hypertension in pregnant women with nonsevere hypertension. Ovid MEDLINE and the Cochrane Library were searched, and only randomized controlled trials (RCTs) were included if they compared the effects of antihypertensive drugs and placebo/no treatment or more intensive and less intensive BP-lowering treatments in nonsevere hypertensive pregnant patients. A random effects model meta-analysis was performed to estimate the pooled risk ratio (RR) for the outcomes. Forty RCTs with 6355 patients were included in the study. BP-lowering treatment significantly prevented severe hypertension (RR, 0.46; 95% CI, 0.37-0.56), preeclampsia (RR, 0.82; 95% CI, 0.69-0.98), severe preeclampsia (RR, 0.38; 95% CI, 0.17-0.84), placental abruption (RR, 0.52; 95% CI, 0.32-0.86), and preterm birth (< 37 weeks; RR, 0.81; 95% CI, 0.71-0.93), while the risk of small for gestational age infants was increased (RR, 1.25; 95% CI, 1.02-1.54). An achieved systolic blood pressure (SBP) of < 130 mmHg reduced the risk of severe hypertension to nearly one-third compared with an SBP of ≥ 140 mmHg, with a significant interaction of the BP levels achieved with BP-lowering therapy. There was no significant interaction between the subtypes of hypertensive disorders of pregnancy and BP-lowering treatment, except for placental abruption. BP-lowering treatment aimed at an SBP < 130 mmHg and accompanied by the careful monitoring of fetal growth might be recommended to prevent severe hypertension.

Out of Office Blood Pressure Measurement in Pregnancy and the Postpartum Period

PURPOSE

Hypertensive disorders of pregnancy are increasing in prevalence and associated with significant maternal and perinatal morbidity and mortality.

RECENT FINDINGS

Increased emphasis has been placed recently on the use of out-of-office (i.e., home and ambulatory) blood pressure (BP) monitoring to diagnose and manage hypertension in the general population. Current guidelines offer limited recommendations on the use of out-of-office BP monitoring during pregnancy and postpartum. This review will discuss the recent literature on BP measurement outside of the office and its use for screening, diagnosis, and treatment in pregnancy and postpartum, and will illuminate areas for future research.

Sildenafil treatment in a nonsevere hypertensive murine model lowers blood pressure without reducing fetal growth

BACKGROUND

Treatment of nonsevere hypertension during pregnancy is controversial. Sildenafil is a phosphodiesterase inhibitor that potentiates nitric oxide by promoting vasodilation. Nitric oxide plays a vital role in mediating the vascular adaptations during pregnancy.

OBJECTIVE

The objective of the study was to determine whether treatment with sildenafil during pregnancy would lower maternal systolic blood pressure without adversely affecting fetal growth.

STUDY DESIGN

Females with nonsevere hypertension (endothelial nitric oxide synthase(+/-)) were cross-bred with normotensive wild-type males. At gestational day 1, pregnant dams were randomized to either sildenafil (0.4 mg/mL per day, comparable dose used in human pregnancy) or water for 3 weeks. Four groups were then generated: wild type (n = 7), wild type-sildenafil (n = 11), endothelial nitric oxide synthase(+/-) (n = 8), and endothelial nitric oxide synthase(+/-)sildenafil (n = 7). On gestational day 18, systolic blood pressure was measured. Dams were killed, fetal and placental weights were obtained, and carotid arteries were dissected to measure in vitro vascular reactivity with a wire-myography system. Responses to phenylephrine, L-NG-nitroarginine methyl ester, acetylcholine, and sodium nitroprusside were studied.

RESULTS

Mean systolic blood pressure was elevated in the endothelial nitric oxide synthase(+/-) dams compared with wild-type controls (P = .03). Treatment with sildenafil decreased systolic blood pressure in the endothelial nitric oxide synthase(+/-)-treated dams compared with nontreated endothelial nitric oxide synthase(+/-) dams (P = .03). No differences were seen in the wild-type dams with or without sildenafil (P = .47). Fetuses from endothelial nitric oxide synthase(+/-) dams were smaller compared with wild-type controls (P < .001); however, when these endothelial nitric oxide synthase(+/-) dams were treated with sildenafil, fetal weight increased compared with the nontreated endothelial nitric oxide synthase(+/-) group (P < .001). No difference were seen in wild-type groups treated or not treated with sildenafil (P = .41). Placental weights were not significantly different among groups (endothelial nitric oxide synthase(+/-)sildenafil vs endothelial nitric oxide synthase(+/-) [P = .48]; wild-type-sildenafil vs wild type [P = .52]). Maximal vascular contraction induced by phenylephrine was blunted in endothelial nitric oxide synthase(+/-) dams treated with sildenafil compared with nontreated endothelial nitric oxide synthase(+/-) dams (P < .01). No change in contractile response was seen in wild-type groups treated or not treated (P = .53). When vessels were preincubated with L-NG-nitroarginine methyl ester, the contractile responses were similar among all groups (P = .54). In addition, maximal vascular relaxation induced by acetylcholine was improved in the endothelial nitric oxide synthase(+/-) dams treated with sildenafil compared with endothelial nitric oxide synthase(+/-) nontreated dams (P < .01). No change in relaxation response was seen in wild-type groups treated or not treated (P = .62). Sodium nitroprusside did not change the contractile response in any of the groups (P = .31).

CONCLUSION

Pregnant dams deficient in endothelial nitric oxide synthase, a nonsevere hypertensive murine model, treated with sildenafil had lower maternal systolic blood pressure, increased fetal growth, and improvement in vascular reactivity. Treatment with sildenafil may be beneficial in pregnancies complicated by nonsevere hypertension.

Management of Type 1 Diabetes in Pregnancy

Women with type 1 diabetes (T1DM) have unique needs during the preconception, pregnancy, and postpartum periods. Preconception counseling is essential for women with T1DM to minimize pregnancy risks. The goals of preconception care should be tight glycemic control with a hemoglobin A1c (A1C) < 7 % and as close to 6 % as possible, without significant hypoglycemia. This will lower risks of congenital malformations, preeclampsia, and perinatal mortality. The safety of medications should be assessed prior to conception. Optimal control of retinopathy, hypertension, and nephropathy should be achieved. During pregnancy, the goal A1C is near-normal at <6 %, without excessive hypoglycemia. There is no clear evidence that continuous subcutaneous insulin infusion (CSII) versus multiple daily injections (MDI) is superior in achieving the desired tight glycemic control of T1DM during pregnancy. Data regarding continuous glucose monitoring (CGM) in pregnant women with T1DM is conflicting regarding improved glycemic control. However, a recent CGM study does provide some distinct patterns of glucose levels associated with large for gestational age infants. Frequent eye exams during pregnancy are essential due to risk of progression of retinopathy during pregnancy. Chronic hypertension treatment goals are systolic blood pressure 110-129 mmHg and diastolic blood pressure 65-79 mmHg. Labor and delivery target plasma glucose levels are 80-110 mg/dl, and an insulin drip is recommended to achieve these targets during active labor. Postpartum, insulin doses must be reduced and glucoses closely monitored in women with T1DM because of the enhanced insulin sensitivity after delivery. Breastfeeding is recommended and should be highly encouraged due to maternal benefits including increased insulin sensitivity and weight loss and infant and childhood benefits including reduced prevalence of overweight. In this article, we discuss the care of pregnant patients with T1DM.

Labetalol for hypertension in pregnancy

INTRODUCTION

Labetalol is one of the most commonly used antihypertensive medications for the treatment of hypertension during pregnancy, an increasingly common and leading cause of maternal mortality and morbidity worldwide.

AREAS COVERED

The literature reviewed included the 2014 Canadian national pregnancy hypertension guideline and its references. The additional published literature was retrieved through searches of Medline, CINAHL, and The Cochrane Library using appropriate controlled vocabulary (e.g., pregnancy, hypertension, pre-eclampsia, pregnancy toxemias) and key words (e.g., diagnosis, evaluation, classification, prediction, prevention, prognosis, treatment, and postpartum follow-up).Results were restricted to systematic reviews, randomized controlled trials, controlled clinical trials, and observational studies published in French or English, Jan-Mar/14. The unpublished literature was identified by searching websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies. We evaluated the impact of interventions on substantive clinical outcomes for mothers and babies.

EXPERT OPINION

Labetalol is a reasonable choice for treatment of severe or non-severe hypertension in pregnancy. However, we should continue our search for other therapeutic options.

Less-tight versus tight control of hypertension in pregnancy

BACKGROUND

The effects of less-tight versus tight control of hypertension on pregnancy complications are unclear.

METHODS

We performed an open, international, multicenter trial involving women at 14 weeks 0 days to 33 weeks 6 days of gestation who had nonproteinuric preexisting or gestational hypertension, office diastolic blood pressure of 90 to 105 mm Hg (or 85 to 105 mm Hg if the woman was taking antihypertensive medications), and a live fetus. Women were randomly assigned to less-tight control (target diastolic blood pressure, 100 mm Hg) or tight control (target diastolic blood pressure, 85 mm Hg). The composite primary outcome was pregnancy loss or high-level neonatal care for more than 48 hours during the first 28 postnatal days. The secondary outcome was serious maternal complications occurring up to 6 weeks post partum or until hospital discharge, whichever was later.

RESULTS

Included in the analysis were 987 women; 74.6% had preexisting hypertension. The primary-outcome rates were similar among 493 women assigned to less-tight control and 488 women assigned to tight control (31.4% and 30.7%, respectively; adjusted odds ratio, 1.02; 95% confidence interval [CI], 0.77 to 1.35), as were the rates of serious maternal complications (3.7% and 2.0%, respectively; adjusted odds ratio, 1.74; 95% CI, 0.79 to 3.84), despite a mean diastolic blood pressure that was higher in the less-tight-control group by 4.6 mm Hg (95% CI, 3.7 to 5.4). Severe hypertension (≥160/110 mm Hg) developed in 40.6% of the women in the less-tight-control group and 27.5% of the women in the tight-control group (P<0.001).

CONCLUSIONS

We found no significant between-group differences in the risk of pregnancy loss, high-level neonatal care, or overall maternal complications, although less-tight control was associated with a significantly higher frequency of severe maternal hypertension. (Funded by the Canadian Institutes of Health Research; CHIPS Current Controlled Trials number, ISRCTN71416914; ClinicalTrials.gov number, NCT01192412.).

Diagnosis, evaluation, and management of the hypertensive disorders of pregnancy

OBJECTIVE

This guideline summarizes the quality of the evidence to date and provides a reasonable approach to the diagnosis, evaluation and treatment of the hypertensive disorders of pregnancy (HDP).

EVIDENCE

The literature reviewed included the previous Society of Obstetricians and Gynaecologists of Canada (SOGC) HDP guidelines from 2008 and their reference lists, and an update from 2006. Medline, Cochrane Database of Systematic Reviews (CDSR), Cochrane Central Registry of Controlled Trials (CCRCT) and Database of Abstracts and Reviews of Effects (DARE) were searched for literature published between January 2006 and March 2012. Articles were restricted to those published in French or English. Recommendations were evaluated using the criteria of the Canadian Task Force on Preventive Health Care and GRADE.

Tight control of mild-moderate pre-existing or non-proteinuric gestational hypertension

BACKGROUND

The question of the target blood pressure in pregnant women with mild-moderate hypertension continues to be an area of debate.

OBJECTIVES

To compare tight versus very tight control of mild-moderate pre-existing or non-proteinuric gestational hypertension for improving outcomes

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 March 2011), CENTRAL (The Cochrane Library 2011, Issue 3), MEDLINE (January 1966 to March 2011), and the metaRegister of Controlled Trials (31 March 2011). We handsearched citation lists of relevant publications, review articles, and included studies.

SELECTION CRITERIA

Randomized controlled trials of tight versus very tight control in pregnant women with mild or moderate pre-existing or non-proteinuric gestational hypertension.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data. We expressed results as risk ratio (RR) or mean differences, together with their 95% confidence intervals (CI).

MAIN RESULTS

We included two studies (256 participants) with mild-moderate pre-existing or non-proteinuric gestational hypertension. There was no evidence of a difference between tight and very tight control groups regarding severe pre-eclampsia (risk ratio (RR) 1.28, 95% CI 0.97 to 1.70; two trials, 256 participants). More women in the tight group were hospitalized during their pregnancy (RR 2.53, 95% CI 1.14 to 5.63; one trial, 125 participants). There was no evidence of a difference in other outcome measures including fetal distress, IUGR, neonatal admission to a NICU, perinatal deaths, induction of labor and cesarean delivery between the tight and the very tight control groups. Gestational age at delivery had a non-significant mean difference (MD) of -0.15 weeks between the tight and very tight control groups (MD -0.15, 95% CI -1.52 to 1.21, random-effects, T² = 0.75, I² = 77%; two trials, 256 participants). The MD in birthweight between the tight and the very tight control group was not significant (MD -100.00 grams, 95% CI -363.69 to 163.69; one trial, 125 participants).

AUTHORS' CONCLUSIONS

For pregnant women with non-severe pre-existing or non-proteinuric gestational hypertension, there is insufficient evidence to determine how tight control of hypertension should be achieved to improve maternal and fetal-neonatal outcomes.