Oral nifedipine versus intravenous labetalol for the treatment of severe hypertension in pregnancy

Optimal treatment for women with acute hypertension in pregnancy; a randomized trial comparing intravenous labetalol versus nicardipine

OBJECTIVES

Blood pressure control in severe hypertension of pregnancy is crucial for mother and neonate. In absence of evidence, guidelines recommend either intravenous labetalol or nicardipine. We compared the effectiveness and safety of these two drugs in women with severe hypertension in pregnancy.

STUDY DESIGN

We performed an open label randomized controlled trial. Women with a singleton pregnancy complicated by severe hypertension (systolic ≥ 160 mmHg and/or diastolic ≥ 110 mmHg) requiring intravenous antihypertensive treatment were randomized to intravenous labetalol or intravenous nicardipine. The primary outcome was a composite adverse neonatal outcome defined as severe Respiratory Distress Syndrome (RDS), Broncho Pulmonary Dysplasia (BPD), Intraventricular Hemorrhage (IVH) IIB or worse, Necrotizing Enterocolitis (NEC), or perinatal death defined as fetal death or neonatal death before discharge from the neonatal intensive care unit (NICU). Based on a power analysis, we estimated that 472 women (236 per group) needed to be included to detect a difference of 15% in the primary outcome with 90% power. The study was halted prematurely at 30 inclusions because of slow recruitment and trial fatigue.

RESULTS

Between August 2018 and April 2022, we randomized 30 women of which 16 were allocated to intravenous nicardipine and 14 to intravenous labetalol. The composite adverse neonatal outcome was not significantly different between the two groups (25 % versus 43 % OR 0.28 (95 % CI 0.05-1.43), p = 0.12)). Respiratory distress syndrome occurred more often in the labetalol group than in the nicardipine group (42.9 % versus 12.5 %). Neonatal hypoglycemia occurred more often in the nicardipine group than in the labetalol group (31 % versus 7 %). Time until blood pressure control was faster in women treated with nicardipine than in women treated with labetalol (45 (15-150 min vs. 120 (60-127,5) min).

CONCLUSION

In our prematurely halted small RCT, we were unable to provide evidence for the optimal choice of treatment for severe hypertension to improve neonatal outcome and/or to obtain faster blood pressure control. Differences in Respiratory distress syndrome and neonatal hypoglycemia between the groups might be the result of coincidental finding due to the small groups included in the study. A larger randomized trial would be needed to determine the safest and most efficacious (intravenous) therapy for severe hypertension in pregnancy. This study emphasizes the challenges of conducting a RCT for the optimal treatment for these women.

Comparing Intravenous Labetalol and Intravenous Hydralazine for Managing Severe Gestational Hypertension

Background Hypertensive disorders of pregnancy are the leading causes of both maternal morbidity and maternal mortality. Hypertensive disorders are acute obstetric emergencies, which refer to various life-threatening medical challenges known to develop during pregnancy, labor, and delivery, requiring urgent attention to reduce blood pressure (BP) for the benefit of the affected mothers and infants. Hydralazine and labetalol have been widely used as the first-line medications in the management of severe hypertension during pregnancy. However, the choice between these two drugs lacks clear evidence regarding their safety and superiority. Several studies have attempted to study intravenous (IV) labetalol versus hydralazine, but very few such comparison studies have been conducted in Africa.  Objective To compare the effectiveness of IV labetalol and IV hydralazine in reducing systolic and diastolic BP in pregnant women with severe hypertension. Also, to determine the time required for hydralazine and labetalol to lower BP to ≤150/100 mmHg, the number of doses needed for each drug, and evaluating maternal and perinatal outcomes. Study design This study employed an open-label randomized clinical trial design conducted in the labor, delivery, and antenatal ward of the Central and Stella Obasanjo Hospital in Benin City. A total of 120 women with severe pregnancy-induced hypertension were randomly assigned to two groups: Group X, consisting of 60 pregnant women, received IV hydralazine at a slow rate of 5 mg for five minutes, repeated every 20 minutes (maximum of five doses) until a blood pressure of ≤150/100 mmHg was achieved. Group Y, also consisting of 60 pregnant women, received IV labetalol in escalating doses of 25, 50, 75, 75, and 75 mg (maximum of 300 mg) every 20 minutes until the blood pressure reached ≤150/100 mmHg. Statistical analysis was performed using SPSS version 23 (IBM Inc., Armonk, New York). Result IV hydralazine achieved the target BP in an average time of 45.80 +/- 25.17 minutes, while IV labetalol took an average of 72.67 +/- 41.80 minutes (p=0.001). The number of doses required to reach the target BP differed significantly between the two drugs. Hydralazine required an average of 1.72 +/- 0.904 doses, whereas labetalol required an average of 3.72 +/- 1.782 doses (p=0.0001). While 45% of women in the hydralazine group attained the target BP with a single dose of hydralazine, only 31.1% of women in the labetalol group were able to attain the target BP with a single dose of labetalol (p=0.02). Overall, target BP was achieved in 55 out of 60 women (91.7%) who were randomized to receive IV hydralazine, whereas 45 out of 60 women (75%) who received IV labetalol achieved the target blood pressure. While hydralazine demonstrated more favorable results in terms of achieving target blood pressure, there were higher incidences of maternal adverse effects in the hydralazine group compared to the labetalol group. However, these adverse effects were not severe enough to warrant discontinuation of the medication. Conclusion IV hydralazine showed faster achievement of the target BP and a lower number of doses required compared to IV labetalol. Additionally, a higher percentage of women in the hydralazine group achieved the target BP with a single dose. However, there were more maternal adverse effects associated with hydralazine, although they were not severe. Perinatal outcomes did not differ significantly between the two groups.

Pharmaceutical administration for severe hypertension during pregnancy: Network meta-analysis

Aims: To evaluate the efficacy of different pharmacologic treatment for severe hypertension during pregnancy. Methods: Two reviewers searched Ovid MEDLINE, Ovid EMbase, and the Cochrane Library for randomized clinical trials from the establishment of the database to 15 July 2021 that were eligible for inclusion and analyzed the pharmaceuticals used for severe hypertension in pregnancy. Results: 29 relevant trials with 2,521 participants were involved. Compared with diazoxide in rate of achieving target blood pressure, other pharmaceuticals, including epoprostenol (RR:1.58, 95%CI:1.01-2.47), hydralazine\dihydralazine (RR:1.57, 95%CI:1.07-2.31), ketanserin (RR:1.67, 95%CI:1.09-2.55), labetalol (RR:1.54, 95%CI:1.04-2.28), nifedipine (RR:1.54, 95%CI:1.04-2.29), and urapidil (RR:1.57, 95%CI:1.00-2.47), were statistically significant in the rate of achieving target blood pressure. According to the SUCRA, diazoxide showed the best therapeutic effect, followed by nicardipine, nifedipine, labetalol, and nitroglycerine. The three pharmaceuticals with the worst therapeutic effect were ketanserin, hydralazine, and urapidil. It is worth noting that the high ranking of the top two pharmaceuticals, including diazoxide and nicardipine, comes from extremely low sample sizes. Other outcomes were reported in the main text. Conclusion: This comprehensive network meta-analysis demonstrated that the nifedipine should be recommended as a strategy for blood pressure management in pregnant women with severe hypertension. Moreover, the conventional pharmaceuticals, including labetalol and hydralazine, showed limited efficacy. However, it was important to note that the instability of hydralazine reducing blood pressure and the high benefit of labetalol with high dosages intakes should also be of concern to clinicians.

Different dosage regimens of nifedipine, labetalol, and hydralazine for the treatment of severe hypertension during pregnancy: a network meta-analysis of randomized controlled trials

OBJECTIVES

This network meta-analysis aimed to compare the efficacy and safety of intravenous (IV) hydralazine, oral nifedipine, and IV labetalol with different dosage regimens in the treatment of severe hypertension during pregnancy.

METHODS

A comprehensive literature search was performed on PubMed, Embase, the Cochrane Library, and ClinicalTrials.gov for randomized controlled trials (RCTs) exploring the effects of hydralazine, nifedipine, and labetalol in the treatment of severe hypertension during pregnancy.

RESULTS

A total of 21 RCTs with 2183 patients comparing 7 regimens (oral nifedipine 50,60,90 mg; hydralazine 15,25 mg; and labetalol 220,300 mg) were identified. Compared with IV labetalol 300 mg, nifedipine 50,60, and 90 mg significantly improved the successful treatment rate of severe hypertension during pregnancy, nifedipine 50 and 90 mg and IV hydralazine 25 mg required significantly fewer doses to achieve target blood pressure (BP), and nifedipine 50 mg took significantly shorter time to achieve target BP. Subgroup analysis showed that only nifedipine 50 mg tablets, not capsules, required a significantly shorter time and fewer doses to achieve target BP than IV labetalol 300 mg. Moreover, nifedipine 60,90 mg showed superior effectiveness than IV hydralazine 15,25 mg in the successful treatment rate of severe hypertension during pregnancy. SUCRA analysis suggested that nifedipine 50,60,90 mg as the better regimens with the lower rates of overall ADR and neonatal complications.

CONCLUSION

These findings demonstrated the superiority of oral nifedipine 50,60,90 mg, especially oral nifedipine 50 mg tablets, in the treatment of severe hypertension during pregnancy than IV labetalol 300 mg, while oral nifedipine 60,90 mg also showed superiority in the successful treatment rate of severe hypertension during pregnancy than IV hydralazine 15,25 mg. However, the limitations of the underlying data indicate that future large-scale and rigorous RCTs are needed to confirm such findings.

Phytosterol enhances oral nifedipine treatment in pregnancy-induced preeclampsia: A placebo-controlled, double-blinded, randomized clinical trial

Preeclampsia is a severe complication which influences pregnant women all around the world, the symptom of which is serious maternal hypertension. Phytosterol is a type of natural compound commonly found in plant products, and has been incorporated into various food vectors and natural drugs. In the paper, the curative effect on preeclampsia by combination of oral nifedipine and phytosterol was assessed. Random grouping was carried out, with 253 preeclampsia patients being registered and taking orally nifedipine+phytosterol or nifedipine+placebo. The time for controlling the blood pressure and the time needed for the occurrence of another hypertensive crisis were defined as primary endpoints. The dosage required for controlling blood pressure, and the adverse effects from infants and mothers were defined as secondary endpoints. The nifedipine+phytosterol group required a remarkably shorter time for controlling blood pressure than the nifedipine+placebo group, an obviously delayed time for the occurrence of new hypertensive crisis, and an obvious lower dosage for controlling blood pressure. There was no difference between the two groups regarding the adverse effects from infants and mothers. Findings in the study suggest that phytosterol is an effective and safe adjuvant of the oral nifedipine and can alleviate the hypertension symptoms in preeclampsia patients.

Efficacy of combined medication of nifedipine and magnesium sulfate on gestational hypertension and the effect on PAPP-A, VEGF, NO, Hcy and vWF

Objective

To investigate the effects of combined medication of nifedipine and magnesium sulfate on the blood pressure, pregnancy-associated plasma protein A (PAPP-A), vascular endothelial growth factor (VEGF), nitric oxide (NO), homocysteine (Hcy) and von Willebrand factor (vWF) in gestational hypertension patients.

Methods

A total of 220 gestational hypertension patients were enrolled as the subjects, and divided into two groups randomly, i.e. the observation group and the control group. In observation group, patients took combined medication of nifedipine and magnesium sulfate, while those in the control group only took magnesium sulfate for treatment. Clinical efficacy, and the changes in blood pressure, PAPP-A, VEGF, NO, Hcy and vWF before and after treatment were compared between two groups.

Results

In the observation group and the control group, total effectiveness rates were 92.7% and 70.9%, respectively (p < 0.05). After treatment, we found significant decreases in PAPP-A, VEGF, NO, Hcy and vWF in patients of two groups, with more significant decreases in the observation group (p < 0.05). Incidence rates of the adverse reactions in two groups were 5.5% and 6.4%, respectively, without any statistically significant differences (p > 0.05). In the observation group, patients had fewer complications (p < 0.05).

Conclusion

Combined medication of magnesium sulfate and nifedipine can decrease the levels of PAPP-A, VEGF, NO, Hcy and vWF in serum as well as the blood pressure of patients with gestational hypertension, with a reduction in incidence rate of complications and improvement in efficacy.

Formulation, Optimization, and In vivo Evaluation of Gastroretentive Drug Delivery System of Nifedipine for the Treatment of Preeclampsia

The study aimed to develop gastroretentive drug delivery system of nifedipine, its optimization, and in vivo evaluation. Bilayered tablet of nifedipine was prepared using central composite design with 3 factors, 5 responses, and 15 experimental trials. Response surface methodology along with numerical and graphical optimization was used to select the best formulation. Scanning electron microscopy study of optimized tablet at different time interval was carried out which showed formation of porous structure on the tablet surface. In vivo studies for optimized formulation were carried out on 10 healthy human volunteers and obtained pharmacokinetic parameters were compared with the marketed formulation, "Nicardia XL." Optimized formulation containing 3.083 mg HPMC K15M, 29.859 mg HPMC E15LV, and 3.541 mg Carbopol 974P releases the drug in a desired manner and remain buoyant for more than 12 h in human stomach. Both the formulations were found to have similar in vitro release profile (f1 4.5089 and f2 55.8274) and also were found to be bioequivalent. Finally, the stability study of the optimized formulation proved the integrity of the optimized formulation. Hence, the data suggest gastroretention as a promising approach to enhance bioavailability of nifedipine.

IV labetalol and oral nifedipine in acute control of severe hypertension in pregnancy-A randomized controlled trial

OBJECTIVE

To compare the efficacy of intravenous labetalol with oral nifedipine in the treatment of severe hypertension in pregnancy with blood pressure ≥160/110 mm Hg.

DESIGN, SETTING AND PARTICIPANTS

We conducted a parallel double-blinded randomized controlled trial between December 2014 to December 2016 in 120 antenatal women of gestational age >28 weeks, admitted with severe hypertension of blood pressure ≥160/110 mm Hg to maternity ward at a tertiary hospital. The labetalol group received 20 mg initially followed by escalating doses of 40 mg, 80 mg, 80 mg and 80 mg (5 doses) every 15 min to a maximum of 300 mg. Nifedipine group received 10 mg initially followed by repeated doses of 20 mg every 15 min (total 5 doses) to a maximum of 90 mg. Vital signs were recorded every 15 min. -The time taken and the number of doses required to achieve the target blood pressure (150/100 mmHg). Survival analysis was used to compare the efficacy of treatment regimens.

RESULTS

Sixty women were randomised to each group and none were lost to follow-up. None of the patients in nifedipine group required labetalol, whereas three patients in labetalol group achieved target BP only after receiving nifedipine was administered after the maximum dose of labetalol.The mean time taken to achieve the target blood pressure in the labetalol group was higher (36.75 min) than in the nifedipine group (27.25 min) [mean difference 9.5 min,p = 0.002]. Nifedipine group required significantly lower doses (1.82 ± 0.83) as compared to labetalol (2.45 ± 1.32) [p = 0.002]. Nifedipine was 1.8 times more likely to achieve target blood pressure (Hazard Ratio = 1.8).

CONCLUSIONS

Both intravenous Labetalol and oral Nifedipine were effective in controlling blood pressure. Nifedipine reduced BP more rapidly than Labetalol. Oral Nifedipine may be a better alternative because of its ease of oral administration and a flat dosing regimen.

Vitamin D Enhances Efficacy of Oral Nifedipine in Treating Preeclampsia with Severe Features: A Double Blinded, Placebo-Controlled and Randomized Clinical Trial

Vitamin D (VD) has exhibited immunomodulatory role in the pathogenesis of preeclampsia. We hypothesize VD potentiate nifedipine treatment for preeclampsia by shortened the time to control blood pressure and prolong time before subsequent hypertensive crisis. We conduct a randomized trial of 683 primigravid women with preeclampsia, who were assigned to different treatment groups, either nifedipine+placebo or nifedipine+VD orally, by random after screening. Primary endpoints include time to control hypertension and time before another hypertensive crisis. Maternal adverse effects including nausea, vomiting, chest pain, mild headache, dizziness, maternal tachycardia, hypotension or shortness of breath, and neonatal parameters including birth weight and Apgar scores, as well as the minimum number of dosages needed to control hypertension were defined as secondary endpoints. Serum levels of cytokines tumor necrosis factor-α (TNF-α) and interleukin-10 (IL-10) were also examined. There was a marked reduction of the time required to control hypertension and a significant lengthening (p = 0.013) of the time before a new hypertensive crisis in participants received nifedipine+VD treatments (41.8 ± 18.3 min), in comparison with the nifedipine+placebo controls (61.1 ± 15.9 min). In women treated with nifedipine+VD, the minimum number of dosages needed to control hypertension was also lower. With regard to adverse effects, no statistical difference was observed between the two treatment groups. Moreover, treatment with VD increased IL-10 and reduced TNF-α serum levels. VD possesses the potential of serving as a safe and effective adjuvant to oral nifedipine in treating women with preeclampsia against hypertension, possibly through the upregulation of IL-10 and the downregulation of TNF-α.

Efficacy of resveratrol to supplement oral nifedipine treatment in pregnancy-induced preeclampsia

OBJECTIVE

Preeclampsia (PE) is a complication affecting pregnant women worldwide, which usually manifests as severe maternal hypertension. Resveratrol (RESV), a naturally existing polyphenol, is known to exhibit beneficial effects in cardiovascular disease including hypertension. We evaluated the outcome of treatment combining oral nifedipine (NIFE) and RESV against PE.

DESIGN AND METHODS

Using a randomized group assignment, 400 PE patients were enrolled and received oral treatments of either NIFE + RESV or NIFE + placebo. Primary endpoints were defined as time to control blood pressure and time before a new hypertensive crisis. Secondary endpoints were defined as the number of doses needed to control blood pressure, maternal and neonatal adverse effects.

RESULTS

Compared with the NIFE + placebo group, the time needed to control blood pressure was significantly reduced in NIFE + RESV group, while time before a new hypertensive crisis was greatly delayed in NIFE + RESV group. The number of treatment doses needed to control blood pressure was also categorically lower in NIFE + RESV group. No differences in maternal or neonatal adverse effects were observed between the two treatment groups.

CONCLUSION

Our data support the potential of RESV as a safe and effective adjuvant of oral NIFE to attenuate hypertensive symptoms among PE patients.

Epigallocatechin gallate enhances treatment efficacy of oral nifedipine against pregnancy-induced severe pre-eclampsia: A double-blind, randomized and placebo-controlled clinical study

WHAT IS KNOWN AND OBJECTIVE

Oral nifedipine is commonly used to treat pre-eclampsia, one of the most severe complications during pregnancy, but its clinical efficacy is less than ideal. Epigallocatechin gallate (EGCG), a natural compound from green tea, could benefit cardiovascular health especially hypertension. We investigated the clinical efficacy of EGCG, when complemented with oral nifedipine, in treating pre-eclampsia.

METHODS

A total of 350 pregnant women with severe pre-eclampsia were recruited and randomized to receive oral nifedipine, together with placebo (NIF+placebo) or EGCG (NIF+EGCG). The primary treatment outcome was the time needed to control blood pressure and interval time before a new hypertensive crisis, whereas the secondary treatment outcome was the number of treatment doses to effectively control blood pressure, maternal adverse effects and neonatal complications.

RESULTS AND DISCUSSION

Comparing NIF+EGCG group to NIF+placebo group, the time needed to control blood pressure was significantly shorter (NIF+EGCG 31.2±16.7 minutes, NIF+placebo 45.3±21.9 minutes; 95% CI 9.7-18.5 minutes), whereas interval time before a new hypertensive crisis was significantly prolonged (NIF+EGCG 7.2±2.9 hours, NIF+placebo 4.1±3.7 hours; 95% CI 2.3-3.9 hours), and the number of treatment dosages needed to effectively control blood pressure was also lower. Between the two treatment groups, no differences in incidence rates of maternal adverse effects or neonatal complications were observed.

WHAT IS NEW AND CONCLUSIONS

EGCG is both safe and effective in enhancing treatment efficacy of oral nifedipine against pregnancy-induced severe pre-eclampsia, but formal validation is required prior to its recommendation for use outside of clinical trials.

Celastrol synergizes with oral nifedipine to attenuate hypertension in preeclampsia: a randomized, placebo-controlled, and double blinded trial

Preeclampsia, a disease mainly manifesting as serious hypertension during pregnancy, affects expectant mothers around the globe. Celastrol, a naturally existing triterpenoid, is known to exhibit beneficial effects attenuating cardiovascular symptoms including hypertension. We here assessed the treatment outcome against preeclampsia with a combined use of celastrol and nifedipine. A total of 626 patients with preeclampsia were enrolled, screened, and assigned by random to groups receiving either nifedipine + placebo or nifedipine + celastrol orally. Time required to control hypertension as well as time before another hypertensive crisis were defined as primary end points. Secondary end points include the number of dosages required to control hypertension, as well as maternal and neonatal adverse effects. The time to control hypertension showed a marked reduction in nifedipine + celastrol group, while time before a new hypertensive crisis was significantly lengthened with the treatment, compared with the nifedipine + placebo group. The number of dosages required to control hypertension was also lower in the nifedipine + celastrol group. The two treatment groups were not statistically different regarding adverse effects, either maternal or neonatal. Results from the current study provide evidence for the potential role of celastrol serving as an effective and safe adjuvant to oral nifedipine against hypertension in patients with preeclampsia.

Oral nifedipine versus intravenous labetalol for severe hypertension during pregnancy: a systematic review and meta-analysis

BACKGROUND

Oral nifedipine is recommended along with labetalol and hydralazine for treatment of severe hypertension during pregnancy by most authorities. Although nifedipine is cheap and easily administered, the usage pattern among health care providers suggests a strong preference for labetalol despite lack of evidence for the same.

OBJECTIVES

To determine the efficacy and safety of oral nifedipine for treatment of severe hypertension of pregnancy compared with intravenous labetalol.

SEARCH STRATEGY

We systematically searched for articles comparing oral nifedipine with intravenous labetalol for the treatment of severe hypertension during pregnancy in any language, over Medline, Cochrane Central Register of Clinical Trials and Google Scholar from inception till February 2014.

SELECTION CRITERIA

We included all RCTs that compared intravenous labetalol with oral nifedipine for treatment of severe hypertension during pregnancy, addressing relevant efficacy and safety outcomes.

DATA COLLECTION AND ANALYSIS

Eligible studies were reviewed, and data were extracted onto a standard form. We used Cochrane review manager software for quantitative analysis. Data were analysed using a fixed effect model.

MAIN RESULTS

The pooled analysis of seven trials (four from developing countries) consisting of 363 woman-infant pairs showed that oral nifedipine was associated with less risk of persistent hypertension (RR 0.42, 95% CI 0.18-0.96) and reported maternal side effects (RR 0.57, 95% CI 0.35-0.94). However, on sensitivity analysis the outcome 'persistent hypertension' was no longer significant. Other outcomes did not reach statistical significance.

CONCLUSION

Oral nifedipine is as efficacious and safe as intravenous labetalol and may have an edge in low resource settings.

TWEETABLE ABSTRACT

Although studies to date are few in number and small, nifedipine shows promise for severe hypertension in pregnancy.