Endothelial dysfunction as a long-term effect of late onset hypertensive pregnancy disorders: High BMI is key

Impact of body mass index on markers of vascular health in normotensive women with history of pre-eclampsia

OBJECTIVE

Obesity and pre-eclampsia (PE) are both associated with vascular dysfunction, which translates into an increased risk for cardiovascular disease in later life. The aim of this study was to investigate whether there is an interaction between body mass index (BMI) and a history of PE in their effects on vascular health.

METHODS

This was an observational case-control study of 30 women with a history of PE who were compared with 31 age- and BMI-matched controls who had an uncomplicated pregnancy. Flow-mediated dilation (FMD), carotid intima-media thickness (cIMT) and carotid distensibility (CD) were measured 6-12 months postpartum. To evaluate the impact of physical fitness, maximum oxygen uptake capacity was assessed using a standardized maximum exhaustion cycling test using breath-by-breath analysis. To specify further BMI subgroups, metabolic syndrome constituents were assessed in all individuals.

RESULTS

Formerly pre-eclamptic women had significantly lower FMD (5.1 ± 2.1% vs 9.4 ± 3.4%; P < 0.01), higher cIMT (0.59 ± 0.09 vs 0.49 ± 0.07 µm; P < 0.01) and lower CD (1.54 ± 0.37%/10 mmHg vs 1.80 ± 0.39%/10 mmHg; P < 0.01) compared with controls. In our study, population BMI correlated negatively with FMD (P = 0.04) but not with cIMT or CD. BMI and PE did not exhibit an interaction effect on these vascular parameters. Physical fitness was lower in women with a history of PE and in women with higher BMI. Constituents of the metabolic syndrome, including insulin, homeostasis model assessment for insulin resistance (HOMA-ir), triglyceride, microalbuminuria and systolic and diastolic blood pressure, were significantly higher in formerly pre-eclamptic women. BMI affected glucose metabolism but not lipids or blood pressure. BMI and PE positively interacted in their effect on insulin (P = 0.04) and HOMA-ir (P = 0.02).

CONCLUSIONS

Both BMI and a history of PE have negative effects on endothelial function, insulin resistance and physical fitness. In formerly pre-eclamptic women, the effect of BMI on insulin resistance was particularly high, suggesting a synergistic effect. Additionally, independently of BMI, a history of PE was associated with reduced FMD and CD and increased cIMT and blood pressure. Recognizing the cardiovascular risk profile is important for informing patients and encouraging targeted lifestyle modifications. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Pravastatin reduces plasma levels of extracellular vesicles in pregnancies at high risk of term preeclampsia

Introduction: Elevated plasma levels of extracellular vesicles have been associated with impaired placentation, angiogenesis imbalance, intravascular inflammation, and endothelial dysfunction in women with preeclampsia, thus suggesting that circulating vesicles may be a good therapeutic target for the treatment of the disease. Recently, statins have been considered a potential treatment for the prevention of preeclampsia because of their pleiotropic effects, including the improvement of endothelial dysfunction and inhibition of inflammatory responses. However, the effects of these drugs on circulating vesicles concentration in women at risk of preeclampsia have not been established. Herein, we aimed to assess the effects of pravastatin on circulating extracellular vesicle generation in women at high risk of term preeclampsia. Methods: In a sample of 68 singleton pregnant women participating in the multicenter, double-blind, placebo-controlled STATIN trial (Nº EducraCT 2016-005206-19 ISRCTN), 35 women received a placebo and 33 women received a 20 mg/day dose of pravastatin for approximately 3 weeks (from 35 to 37 weeks of gestation until delivery). Large extracellular vesicles were characterized and quantified by flow cytometry using annexin V and cell-specific antibodies directed against platelet, endothelial, leukocyte, and syncytiotrophoblast cell surface markers. Results: In women who received the placebo, a significant increase in the plasma levels of large extracellular vesicles from platelets (34%, p < 0.01), leukocytes (33%, p < 0.01), monocytes (60%, p < 0.01), endothelial cells (40%, p < 0.05), and syncytiotrophoblast cells (22%, p < 0.05) were observed. However, treatment with pravastatin significantly reduced the plasma levels of large extracellular vesicles from platelets (42%, p < 0.001), leukocytes (25%, p < 0.001), monocytes (61%, p < 0.001), endothelial cells (69%, p < 0.001), activated endothelial cells (55%, p < 0.001), and syncytiotrophoblast cells (44%, p < 0.001). Discussion: These results indicate that pravastatin reduces the levels of activated cell-derived membrane vesicles from the maternal vasculature, blood, and placental syncytiotrophoblast of women at high risk of term preeclampsia, suggesting that this statin may be beneficial in reducing endothelial dysfunction and pro-inflammatory and pro-coagulatory state characteristics of the disease.

Paeoniflorin alleviates NG-nitro-L-arginine methyl ester (L-NAME)-induced gestational hypertension and upregulates silent information regulator 2 related enzyme 1 (SIRT1) to reduce H2O2-induced endothelial cell damage

Pregnancy-induced hypertension (PIH) is a leading cause of maternal mortality. Paeoniflorin has been reported to alleviate hypertension, thus relieving the injury of target organ. This study aimed to investigate the role of paeoniflorin in PIH development by regulating SIRT1 in rats. The mean arterial pressure (MAP), urine protein and histopathological damage of placenta in gestational hypertension rats were, respectively, detected by noninvasive tail-artery pressure measuring instrument, BCA method and H&E staining. The viability of human umbilical vein endothelial cells (HUVECs) treated with paeoniflorin or/and H₂O₂ was observed by CCK-8 assay. SIRT1 protein expression in HUVECs treated with paeoniflorin or/and H₂O₂ was analyzed by Western blot. Tunel assay, wound healing assay and tube formation assay were used to detect the apoptosis, migration and tube formation of HUVECs administrated with paeoniflorin or/and H₂O₂ or/and EX527 (SIRT1 inhibitor). As a result, MAP, urine protein and histopathological damage of placenta were enhanced in PIH rats, which were then alleviated by paeoniflorin. Paeoniflorin decreased the levels of sFlt-1, PlGF and VEGF in serum and placental tissues of gestational hypertension rats as well as the inflammatory response and oxidative stress. In addition, paeoniflorin promoted the expressions of SIRT1 and NO/eNOS and inhibited the production of iNOS in gestational hypertension rats to improve vascular endothelial cell injury. However, SIRT1 inhibition could suppress the protective effects of paeoniflorin on endothelial dysfunction of H₂O₂-induced HUVECs. In conclusion, paeoniflorin could improve gestational hypertension development by upregulating SIRT1.

Novel Cardiovascular Biomarkers Associated with Increased Cardiovascular Risk in Women With Prior Preeclampsia/HELLP Syndrome: A Narrative Review

Evidence has shown that women with a history of preeclampsia or haemolysis, elevated liver enzymes and low platelets (HELLP) syndrome have an increased risk of cardiovascular disease later in life. Recommendations for screening, prevention and management after such pregnancies are not yet defined. The identification of promising non-traditional cardiovascular biomarkers might be useful to predict which women are at greatest risk. Many studies are inconsistent and an overview of the most promising biomarkers is currently lacking. This narrative review provides an update of the current literature on circulating cardiovascular biomarkers that may be associated with an increased cardiovascular disease risk in women after previous preeclampsia/HELLP syndrome. Fifty-six studies on 53 biomarkers were included. From the summary of evidence, soluble fms-like tyrosine kinase-1, placental growth factor, interleukin (IL)-6, IL-6/IL-10 ratio, high-sensitivity cardiac troponin I, activin A, soluble human leukocyte antigen G, pregnancy-associated plasma protein A and norepinephrine show potential and are interesting candidate biomarkers to further explore. These biomarkers might be potentially eligible for cardiovascular risk stratification after preeclampsia/HELLP syndrome and may contribute to the development of adequate strategies for prevention of hypertension and adverse events in this population.

A STUDY ON THE CORRELATION BETWEEN THE ENDOTHELIN-1, NITRIC OXIDE FUNCTION AND THE RENAL HEMODYNAMICS IN PATIENTS WITH HYPERTENSIVE DISORDERS IN PREGNANCY IN HUBEI

Objective: To analyze the correlation between the vascular endothelial function (characterized by endothelin-1 and nitric oxide) and the renal hemodynamics in patients with hypertensive disorders in pregnancy (HDP) by color Doppler ultrasound.

Method: Depending on the severity of the disease, 76 HDP patients were divided into three groups, namely, pregnancy-induced hypertension (PIH) group ([Formula: see text]), mild preeclampsia (PE) group ([Formula: see text]), and severe PE group ([Formula: see text]). In the meantime, 28 healthy pregnant women were selected as controls. Color Doppler ultrasound was performed to determine the following parameters in the interlobar arteries of the kidney: Resistance index (RI), peak end-diastolic velocity (EDV), pulsatility index (PI), peak systolic velocity (PSV), and S/D ratio. The correlations of these parameters with the serum levels of ET-1 and NO were then analyzed.

Result: (1) In the interlobar arteries of the kidney, RI, S/D, PI were positively significantly correlated to the serum level of ET-1 in HDP patients (All [Formula: see text]) and negatively to the serum level of NO (All [Formula: see text]). (2) RI, S/D, PI of the mild and severe PE groups were significantly higher than those of the control group (All [Formula: see text]). However, EDV of the mild and severe PE groups was significantly lower than that of the control group (All [Formula: see text]). (3) The serum level of ET-1 was significantly higher in the HDP patients than in the control group ([Formula: see text]). However, the serum level of NO was significantly lower in the former than in the latter ([Formula: see text]). As HDP became more severe, there was an elevation in the serum level of ET-1 and a decrease in NO.

Conclusion: Indicators of renal hemodynamics measured by color Doppler ultrasound were correlated to the serum levels of ET-1 and NO characterizing the vascular endothelial function. They were sensitive indicators reflecting hemodynamic changes and renal impairment in HDP patients.

Prenatal hypoxia increases blood pressure in male rat offspring and affects their response to artificial light at night

Prenatal hypoxia (PH) has negative consequences on the cardiovascular system in adulthood and can affect the responses to additional insults later in life. We explored the effects of PH imposed during embryonic day 20 (10.5% O2 for 12 h) on circadian rhythms of systolic blood pressure (BP) and heart rate (HR) in mature male rat offspring measured by telemetry. We evaluated: (1) stability of BP and HR changes after PH; (2) circadian variability of BP and HR after 2 and 5 weeks of exposure to artificial light at night (ALAN; 1-2 lx); and (3) response of BP and HR to norepinephrine. PH increased BP in the dark (134 ± 2 mmHg vs. control 127 ± 2 mmHg; p = 0.05) and marginally in the light (125 ± 1 mmHg vs. control 120 ± 2 mmHg) phase of the day but not HR. The effect of PH was highly repeatable between 21- and 27-week-old PH male offspring. Two weeks of ALAN decreased the circadian variability of HR (p < 0.05) and BP more in control than PH rats. After 5 weeks of ALAN, the circadian variability of HR and BP were damped compared to LD and did not differ between control and PH rats (p < 0.05). Responses of BP and HR to norepinephrine did not differ between control and PH rats. Hypoxia at the end of the embryonic period increases BP and affects the functioning of the cardiovascular system in mature male offspring. ALAN in adulthood decreased the circadian variability of cardiovascular parameters, more in control than PH rats.

Body Mass Index Influence on the Clinical Outcomes for Nonvalvular Atrial Fibrillation Patients Admitted to a Hospital Treated with Direct Oral Anticoagulants: A Retrospective Cohort Study

BACKGROUND

Considering that the current fixed dose of direct oral anticoagulants (DOACs) might have insufficient anticoagulation effect for overweight patients, the aim of this study was to compare the effectiveness and safety of anticoagulation between dabigatran and rivaroxaban in different body mass index (BMI) population.

METHODS

We conducted a retrospective cohort study of 2402 DOAC anticoagulated patients with atrial fibrillation who underwent catheter ablation (1290 dabigatran, 53.7% and 1112 rivaroxaban, 46.3%) between January 2017 and December 2018. Patients were distributed based on the BMI into nonobese (1362, BMI <25 kg/m2), preobese (521, BMI 25.0-29.9 kg/m2), class I obese (344, BMI 30.0-34.9 kg/m2) and class II+ obese (175, BMI ≥35.0 kg/m2). We collected information regarding clinical features, laboratory data, bleeding complications and systemic embolic events from the electrical medical records system during 12 months.

RESULTS

The incidence of systemic embolism and stroke complications was higher in the class II+ obese group (P=0.001 and P=0.003). The incidence of bleeding complications and the levels of anticoagulation parameters under the bleeding threshold were similar among the four groups (P>0.05). Cumulative Kaplan-Meier analysis illustrated that rivaroxaban-treated patients who belonged to higher BMI subgroups were more likely to experience shorter time to thrombosis (TTT) (12-month TTT rates of 0.5% for nonobese vs 1.7% for class I obese patients, HR=3.716, P=0.005; 12-month TTT rates of 0.5%, for nonobese vs 4.0% for class II+ obese patients, HR=6.843, P=0.001). However, no statistical significant difference in terms of the time to bleeding complications and the time to cumulative events among the four groups was observed. By multivariate analysis, a higher BMI value (BMI ≥25 kg/m2) (P=0.019; OR=2.094, 95%CI: 1.129-3.883) was an independent predictor for thrombosis in patients treated with dabigatran or rivaroxaban. Positive linear relationship was observed between BMI levels and occurrence rate of thrombosis and bleeding in under anticoagulation patients with NVAF (R2=0.451 and R2=0.383, respectively).

CONCLUSION

The fixed dose of 15 mg rivaroxaban might carry a risk of under exposure, which would lead to an increase of thromboembolic complications in patients with high BMI. Therefore, rivaroxaban dose increase was suggested for obese patients. Use of DOACs appears to have considerable safety in obese patients.

Hypertensive disorders of pregnancy and the risk of chronic kidney disease: A Swedish registry-based cohort study

BACKGROUND

Hypertensive disorders of pregnancy (HDP) (preeclampsia, gestational hypertension) are associated with an increased risk of end-stage kidney disease (ESKD). Evidence for associations between HDP and chronic kidney disease (CKD) is more limited and inconsistent. The underlying causes of CKD are wide-ranging, and HDP may have differential associations with various aetiologies of CKD. We aimed to measure associations between HDP and maternal CKD in women who have had at least one live birth and to identify whether the risk differs by CKD aetiology.

METHODS AND FINDINGS

Using data from the Swedish Medical Birth Register (MBR), singleton live births from 1973 to 2012 were identified and linked to data from the Swedish Renal Register (SRR) and National Patient Register (NPR; up to 2013). Preeclampsia was the main exposure of interest and was treated as a time-dependent variable. Gestational hypertension was also investigated as a secondary exposure. The primary outcome was maternal CKD, and this was classified into 5 subtypes: hypertensive, diabetic, glomerular/proteinuric, tubulointerstitial, and other/nonspecific CKD. Cox proportional hazard regression models were used, adjusting for maternal age, country of origin, education level, antenatal BMI, smoking during pregnancy, gestational diabetes, and parity. Women with pre-pregnancy comorbidities were excluded. The final sample consisted of 1,924,409 women who had 3,726,554 singleton live births. The mean (±SD) age of women at first delivery was 27.0 (±5.1) years. Median follow-up was 20.7 (interquartile range [IQR] 9.9-30.0) years. A total of 90,917 women (4.7%) were diagnosed with preeclampsia, 43,964 (2.3%) had gestational hypertension, and 18,477 (0.9%) developed CKD. Preeclampsia was associated with a higher risk of developing CKD during follow-up (adjusted hazard ratio [aHR] 1.92, 95% CI 1.83-2.03, p < 0.001). This risk differed by CKD subtype and was higher for hypertensive CKD (aHR 3.72, 95% CI 3.05-4.53, p < 0.001), diabetic CKD (aHR 3.94, 95% CI 3.38-4.60, p < 0.001), and glomerular/proteinuric CKD (aHR 2.06, 95% CI 1.88-2.26, p < 0.001). More modest associations were observed between preeclampsia and tubulointerstitial CKD (aHR 1.44, 95% CI 1.24-1.68, p < 0.001) or other/nonspecific CKD (aHR 1.51, 95% CI 1.38-1.65, p < 0.001). The risk of CKD was increased after preterm preeclampsia, recurrent preeclampsia, or preeclampsia complicated by pre-pregnancy obesity. Women who had gestational hypertension also had increased risk of developing CKD (aHR 1.49, 95% CI 1.38-1.61, p < 0.001). This association was strongest for hypertensive CKD (aHR 3.13, 95% CI 2.47-3.97, p < 0.001). Limitations of the study are the possibility that cases of CKD were underdiagnosed in the national registers, and some women may have been too young to have developed symptomatic CKD despite the long follow-up time. Underreporting of postpartum hypertension is also possible.

CONCLUSIONS

In this study, we found that HDP are associated with increased risk of maternal CKD, particularly hypertensive or diabetic forms of CKD. The risk is higher after preterm preeclampsia, recurrent preeclampsia, or preeclampsia complicated by pre-pregnancy obesity. Women who experience HDP may benefit from future systematic renal monitoring.

Postpartum blood pressure trends are impacted by race and BMI

OBJECTIVE

Our objective was to evaluate postpartum blood pressure trends, and time to resolution of hypertension among women with hypertensive disorders of pregnancy, specifically focusing on impact of race and BMI on these trends.

METHODS

We performed a secondary analysis of a randomized trial that utilized a text-message based home blood pressure monitoring system. BPs for this study included both inpatient postpartum BPs as well as home BPs obtained from the text-based program. Women were followed from 12 h of delivery to 16 days postpartum. Outcomes were: (1) postpartum BP trend summaries from a linear mixed-effects regression model and (2) time to resolution of hypertension (defined as ≥ 48 h of BPs < 140/90) depicted using Kaplan Meier survival curves with hazard ratio estimates of association using Cox models.

RESULTS

Eighty-four women were included, of which 63% were black. Non-black women with a BMI < 35 kg/m² had steady decreases in systolic BP whereas other groups peaked around 6.5 days postpartum. BPs for women in the BMI < 35 group, regardless of race, remained in the normotensive range. Conversely, women with a BMI ≥ 35 had a systolic BP peak into the hypertensive range prior to declining. Diastolic BP peaked at an average of 8.5 days postpartum. Time to resolution of BPs differed by race and BMI groups (p = 0.012). Non-black women with a BMI < 35 had the shortest time to resolution and 81% of these women had resolution of hypertension. Only 49% of black women with a BMI < 35 had resolution of hypertension and approximately 40% of both black and non-black women with BMI ≥ 35 had resolution of hypertension.

CONCLUSION

We identified race and BMI to be determinants of postpartum BP trends and hypertension resolution. Further study is needed to determine if race and BMI targeted postpartum hypertension interventions may lead to faster blood pressure recovery and lower maternal morbidity postpartum.

Syncytiotrophoblast-Derived Extracellular Vesicles in Pathophysiology of Preeclampsia

Preeclampsia is a common obstetric complication associated with pregnancy and it endangers lives of the mother and the infant. The histopathological changes associated with preeclampsia include systemic endothelial dysfunction, persistent inflammatory state, and coagulation and fibrinolysis dysregulations. Preeclampsia is considered to be caused by the systemic vasoconstriction of small arteries and disruption of the endothelial integrity, resulting in hypertension, proteinuria, and multiple organ dysfunction. However, mediators that trigger or propagate the pathology of preeclampsia remain poorly defined. Syncytiotrophoblast-derived extracellular vesicles (SDEVs) are increasingly recognized as a key mediator for the development of preeclampsia, but the underlying mechanisms through which these SDEVs are released and induce systemic responses are not fully understood. This review focuses on multiple roles of SDEVs in the pathogenesis of preeclampsia.

Maternal serum trimethylamine-N-oxide is significantly increased in cases with established preeclampsia

PURPOSE

To compare the levels of trimethylamine-N-oxide (TMAO) in sera of normal and preeclamptic pregnancies and to explore whether serum TMAO level was associated with the severity of preeclampsia.

MATERIALS AND METHODS

Eighty-six pregnant women in the third trimester were enrolled in this case control study. Levels of TMAO were quantified by a novel liquid chromatography/tandem mass spectrometry-based method in fasting serum samples from 43 preeclamptic women and 43 normotensive controls. Clinical characteristics, serum biomarkers of inflammation (IL-1β) and biomarkers of endothelial dysfunction (sVCAM-1, sFlt-1) were assessed.

RESULTS

TMAO levels were significantly higher in women with preeclampsia than those with normal pregnancy. The serum levels of TMAO were positively correlated with systolic blood pressure (r = 0.602, P < 0.001), urinary protein levels (r = 0.557, P < 0.001) and the serum levels of IL-1β (r = 0.633, P < 0.001), sVCAM-1 (r = 0.719, P < 0.001) as well as sFlt-1 (r = 0.763, P < 0.001) in patients with PE.

CONCLUSIONS

Elevated TMAO levels are associated with higher risk of preeclampsia and correlate with increased systemic inflammation and endothelial dysfunction. Further validation of these findings with more robust multicenter prospective and longitudinal characterization of maternal serum TMAO in pregnancy may be carried out in subsequent investigations to determine its suitability as a predictive biomarker for preeclampsia.