Race/ethnicity differences in response to acute antihypertensive treatment of peripartum severe hypertension.

BACKGROUND: Hypertensive disorders of pregnancy increase maternal morbidity, mortality, and long-term risk for cardiovascular disease. The rising incidence of chronic hypertension and preeclampsia disproportionately affects people of color. There is a paucity of published data examining differences in the effectiveness of acute antihypertensive agents between pregnant patients of different races/ethnicities. We aimed to determine if the effectiveness of acute antihypertensive agents for peripartum severe hypertension differs by race/ethnicity. METHODS: A retrospective cohort study of patients with severe peripartum hypertension (systolic blood pressure ≥ 160 mmHg and/or diastolic blood pressure ≥ 110 mm Hg confirmed within 15 min) to determine whether the effectiveness of blood pressure control using nationally recommended medications (hydralazine, labetalol, nifedipine) differed by race/ethnicity. The primary outcome was reduction and maintenance of blood pressure to target ranges (140-150/90-100 mm Hg or below) for ≥4 h in each race/ethnicity group. Statistical tests included χ2, Fisher's exact, analysis of variance, and multivariable logistic regression. RESULTS: Of 729 patients receiving treatment for severe peripartum hypertension, all medications were effective (overall 86.4% efficacy) at controlling blood pressure. Labetalol was the most effective medication in White patients (93.0 vs. 74.7% for nifedipine and 86.5% for hydralazine, p < .001). No overall differences in medication effectiveness were found in Black, Asian, or LatinX patients. Black and Asian patients were more likely to experience >1 hypertensive episode [51.0 and 49.0%, respectively vs. 35.4% (White) and 40.0% (LatinX), p = .008]. CONCLUSION: Currently recommended therapies for severe peripartum hypertension are effective in controlling blood pressure for ≥4 h in patients of all race/ethnic groups. Labetalol was the most effective medication in White patients with no overall differences in medication effectiveness in Black, Asian, or LatinX patients.

Nonadherence to treatment protocol for severe hypertension in pregnancy.

BACKGROUND: Hypertensive disorders of pregnancy are one of the leading causes of maternal mortality and severe morbidity. The American College of Obstetricians and Gynecologists recommends treatment of persistent severe hypertension because this has been shown to improve overall outcomes. Treatment remains inconsistent and may be influenced by patient-level sociodemographic and clinical characteristics. OBJECTIVE: This study aimed to identify which factors are associated with nonadherence to an institutional protocol for the treatment of severe hypertension in pregnancy. STUDY DESIGN: Retrospective cohort study of patients who had persistent severe hypertension (≥2 systolic blood pressures ≥160 mm Hg and/or diastolic blood pressures >110 mm Hg between 15 and 60 minutes apart) during their delivery hospitalization in 3 hospitals within an integrated health system from February 1, 2018 to March 1, 2020. Adherence to an institutional protocol was defined as receiving antihypertensive medication within 1 hour of a second severe blood pressure measurement. Demographic information, medical comorbidities, and delivery hospitalization characteristics were compared between women who received treatment based on institutional protocol and those who did not. Patient zone improvement plan codes were linked to neighborhood-level data from the US Census Bureau's American Community Survey to extract socioeconomic characteristics. A multivariable logistic regression was performed to evaluate factors associated with delayed treatment while adjusting for potential confounders. RESULTS: Of the 996 patients included, 449 (45%) received treatment within 60 minutes and 547 (55%) did not. Having an elevated, nonsevere range blood pressure (adjusted odds ratio, 0.55; 95% confidence interval, 0.38-0.79) or a severe range blood pressure (adjusted odds ratio, 0.25; 95% confidence interval, 0.16-0.38) on admission, persistent severe hypertension ≥1 hour before or after delivery (adjusted odds ratio, 0.27; 95% confidence interval, 0.27-0.45), and chronic hypertension (adjusted odds ratio, 0.58; 95% confidence interval, 0.37-0.93) were associated with timely treatment. Hospital site (adjusted odds ratio, 1.97; 95% confidence interval, 1.18-3.28) and increasing gestational age (adjusted odds ratio, 1.14; 95% confidence interval, 1.07-1.21) were associated with nonadherence to treatment protocol. A subanalysis evaluating treatment in 344 (35%) patients who had a nonelevated blood pressure on admission showed that White race, persistent severe hypertension within 1 hour of delivery, increasing gestational age, body mass index, twin gestation, preferred language other than English or Spanish, and a higher neighborhood unemployment rate were associated with nonadherence to treatment protocol. CONCLUSION: Several factors were associated with nonadherence to an institutional protocol for treatment of persistent severe hypertension. Provider bias may impact whether treatment is executed or not. Awareness of these risk factors may improve timely administration of antihypertensive medication in pregnant and postpartum patients.

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.

A trial of oral nifedipine and oral labetalol in preeclampsia hypertensive emergency treatment.

This observational retrospective cohort study was conducted to compare oral nifedipine and labetalol for emergency treatment of hypertension in preeclamptic patients. Time (minutes) and necessary doses were outlined to achieve blood pressure lower than 150/95 mmHg. In 14 patients with preeclampsia, 55 hypertensive emergencies were identified (BP >150/95). Of these emergencies, 43 were treated with oral nifedipine 10 mg (10 patients) and 12 with oral labetalol 100 mg (4 patients). To achieve a target blood pressure under 150/95, these doses were repeated as necessary every 20 min, up to a maximum of 4 doses. Oral nifedipine reduced BP more rapidly (31.30 vs. 53.50 min, p = .03). No maternal or foetal adverse events were observed and no major differences were found according to the type of delivery. Oral nifedipine is faster than and at least as safe as labetalol in pre-eclampsia hypertensive emergency treatment.

Oral antihypertensive therapy for severe hypertension in pregnancy and postpartum: a systematic review.

BACKGROUND: Pregnant and postpartum women with severe hypertension are at increased risk of stroke and require blood pressure (BP) reduction. Parenteral antihypertensives have been most commonly studied, but oral agents would be ideal for use in busy and resource-constrained settings. OBJECTIVES: To review systematically, the effectiveness of oral antihypertensive agents for treatment of severe pregnancy/postpartum hypertension. SEARCH STRATEGY: A systematic search of MEDLINE, EMBASE and the Cochrane Library was performed. SELECTION CRITERIA: Randomised controlled trials in pregnancy and postpartum with at least one arm consisting of a single oral antihypertensive agent to treat systolic BP ≥ 160 mmHg and/or diastolic BP ≥ 110 mmHg. DATA COLLECTION AND ANALYSIS: Cochrane RevMan 5.1 was used to calculate relative risk (RR) and weighted mean difference by random effects. MAIN RESULTS: We identified 15 randomised controlled trials (915 women) in pregnancy and one postpartum trial. Most trials in pregnancy compared oral/sublingual nifedipine capsules (8-10 mg) with another agent, usually parenteral hydralazine or labetalol. Nifedipine achieved treatment success in most women, similar to hydralazine (84% with nifedipine; relative risk [RR] 1.07, 95% confidence interval [95% CI] 0.98-1.17) or labetalol (100% with nifedipine; RR 1.02, 95% CI 0.95-1.09). Less than 2% of women treated with nifedipine experienced hypotension. There were no differences in adverse maternal or fetal outcomes. Target BP was achieved ~ 50% of the time with oral labetalol (100 mg) or methyldopa (250 mg) (47% labetelol versus 56% methyldopa; RR 0.85 95% CI 0.54-1.33). CONCLUSIONS: Oral nifedipine, and possibly labetalol and methyldopa, are suitable options for treatment of severe hypertension in pregnancy/postpartum.