Ambulatory blood pressure measurements in mid-pregnancy and development of hypertensive pregnancy disorders

Higher daytime systolic BP, prepregnancy BMI and an elevated sFlt-1/PlGF ratio predict the development of hypertension in normotensive pregnant women

BACKGROUND

The risk of hypertensive disorders of pregnancy (HDP) varies in women with gestational diabetes mellitus (GDM), depending on the degree of insulin resistance and is also influenced by obesity. The aim of this study was to evaluate clinical features, blood pressure (BP) profiles and inflammatory markers, to identify patients with an elevated risk of developing HDP.

METHODS

A total of 146 normotensive pregnant women were studied. We analysed the relationships of BP profiles detected by ambulatory blood pressure monitoring (ABPM) with serum biomarkers and angiogenic factors and their association with the development of HDP.

RESULTS

Fourteen (9.6%) women developed HDP, of which 11 had GDM and 8 had obesity. Women with HDP had higher values of 24-h and daytime systolic/diastolic BP (113/69 vs. 104/64; 115/72 vs. 106/66 mmHg, respectively; p <  0.05). Higher levels of leptin (10.97 ± 0.82 vs. 10.2 ± 1.11; p = 0.018) andmonocyte chemoattractant protein-1 (MCP-1) (5.24 ± 0.60 vs. 4.9 ± 0.55; p = 0.044) and a higher soluble fms-like tyrosine kinase-1/placental growth factor (sFlt-1/PlGF) ratio (4.37 ± 2.2 vs. 2.2 ± 1.43; p = 0.003) were also observed in the HDP patients. Multivariate analysis showed that a higher sFlt-1/PlGF ratio was associated with an increased risk of developing HDP [OR = 2.02; IC 95%: 1.35-3.05]. Furthermore, higher daytime systolic BP [OR = 1.27; IC 95% 1.00-1.26] and prepregnancy body mass index (BMI) [OR = 1.14; IC 95%: 1.01-1.30] significantly increased the risk of developing HDP.

CONCLUSIONS

Higher daytime systolic BP values, prepregnancy BMI and the sFlt-1/PlGF ratio are useful for identifying normotensive pregnant women with an increased risk of developing HDP.

Blood Pressure Monitoring and Perinatal Outcomes in Normotensive Women with Gestational Diabetes Mellitus

Alterations in ambulatory blood pressure detected by monitoring (ABPM) have been associated with perinatal complications in hypertensive pregnant women. Aim: To establish the relationships between the blood pressure (BP) profiles detected by ABPM and adverse perinatal outcomes in normotensive women with gestational diabetes mellitus (GDM). Methods: A prospective study of normotensive women in whom 24 h ABPM was performed at 28–32 weeks of pregnancy. The obstetric and perinatal outcomes were evaluated. Results: Two hundred patients were included. Thirty-seven women with GDM and obesity had significantly higher mean systolic BP (SBP) and nocturnal SBP and diastolic BP (DBP) compared to women with only GDM (n = 86). Nocturnal SBP (OR = 1.077; p = 0.015) and obesity (OR = 1.131; p = 0.035) were risk factors for the development of hypertensive disorders of pregnancy (HDPs). Mothers of newborns with neonatal complications (n = 27) had higher nocturnal SBP (103.8 vs. 100 mmHg; p = 0.047) and DBP (62.7 vs. 59.4; p = 0.016). Women who delivered preterm (n = 10) had higher BP and a non-dipper pattern (p = 0.005). Conclusions: Nocturnal SBP was a predictor of HDPs in normotensive women with obesity or GDM. Alterations in ABPM in these patients were associated with poor obstetric and perinatal outcomes.

Is home blood-pressure monitoring in hypertensive disorders of pregnancy consistent with clinic recordings?

OBJECTIVE

To assess the agreement between home blood-pressure monitoring (HBPM) and blood-pressure measurements in a clinic setting, in a cohort of pregnant women with hypertensive disorders of pregnancy (HDP).

METHODS

This was a cohort study of 147 pregnant women with HDP conducted at St George's Hospital, University of London, London, UK, between 2016 and 2017. Inclusion criteria were chronic hypertension, gestational hypertension or high risk of developing pre-eclampsia, no significant proteinuria and no hematological or biochemical abnormalities. Each included patient was prescribed a personalized schedule of hospital visits and blood-pressure measurements, according to their individual risk as per UK National Institute for Health and Care Excellence guidelines. The blood-pressure measurement at the clinic and the HBPM reading obtained closest to that hospital visit were paired for analysis. Only one pair of measurements was used per patient. Differences between home and clinic blood-pressure measurements were tested using the Wilcoxon signed rank test or paired t-test, and were also assessed visually using Bland-Altman plots. Comparison of the binary outcomes was performed using McNemar's chi-square test. Subgroup analysis was performed in the following gestational-age windows: < 14 weeks, 15-22 weeks, 23-32 weeks and 33-42 weeks' gestation.

RESULTS

A total of 294 blood-pressure measurements from 147 women were included in the analysis. Median systolic HBPM measurements were significantly lower than clinic measurements (132.0 (interquartile range (IQR), 123.0-140.0) mmHg vs 138.0 (IQR, 132.0-146.5) mmHg; P < 0.001). When stratified according to gestational age, systolic blood-pressure measurements obtained at home were significantly lower than those at clinic in all gestational-age periods except 23-32 weeks' gestation (P = 0.057). Median diastolic blood-pressure measurements at home were also significantly lower than those at clinic (85.0 (IQR, 77.0-90.0) mmHg vs 89.0 (IQR, 82.0-94.0) mmHg; P < 0.001). When stratified according to gestational age, diastolic HBPM measurements were significantly lower in the periods 5-14 weeks (P < 0.001), 15-22 weeks (P = 0.008) and 33-42 weeks (P < 0.001), compared with clinic measurements. The incidence of clinically significant systolic and diastolic hypertension based on clinic blood-pressure measurements was four to five times higher than that based on HBPM measurements (P < 0.001 and P = 0.005, respectively).

CONCLUSIONS

Our study shows that, in women with HDP, blood pressure measured at home is lower than that measured in a clinic setting. This is consistent with observations in non-pregnant adults, in whom home and ambulatory monitoring of hypertensive patients is recommended. As such, HBPM has the potential to reduce the number of false-positive diagnoses of severe hypertension and unnecessary medical interventions in women with HDP. This must be carefully weighed against the risk of missing true-positive diagnoses. Prospective studies investigating the use of HBPM in pregnant women are urgently needed to determine the relevant blood-pressure thresholds for HBPM, and interval and frequency of monitoring. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Hypertensive complications of pregnancy: A clinical overview

Hypertensive disorders in pregnancy are a worldwide health problem for women and their infants complicating up to 10% of pregnancies and associated with increased maternal and neonatal morbidity and mortality. In Europe, 2.3-3% of pregnancies are complicated by preeclampsia. Gestational diabetes, obesity, no previous or multiple births, maternal age less than 20 or greater than 35years old and thrombophilia can be some of the possible factors related to increased risk for hypertension in pregnancy. Complications of hypertension during pregnancy affect both mothers and their infants. Ambulatory blood pressure monitoring helps to distinguish true hypertension from the white coat as pregnant women with office abnormal values may have normal out of office blood pressure. Imbalance between proangiogenic and antiangiogenic factors in placenta may lead to endothelial dysfunction, vasoconstriction, activation of the coagulation system, and hemolysis. Carotid intima-media thickness, pulse wave velocity, augmentation index, and arterial wall tension were found to be significantly increased in women with preeclampsia compared to normotensive pregnant women. Uterine artery Doppler and serum biomarkers can be used to evaluate the probability of hypertension and complications during pregnancy, but further research in the field is needed. Lately, micro ribonucleic acids have also been the focus of research as potential biomarkers.