Cardiovascular events following pregnancy complicated by pre-eclampsia with emphasis on comparison between early- and late-onset forms: systematic review and meta-analysis

Particulate matter and hypertensive disorders in pregnancy: systematic review and meta-analysis

OBJECTIVES

We aimed to quantitatively synthesize the association between maternal exposure to particulate matter (PM; including PM <2.5 μm and PM <10 μm) and hypertensive disorders in pregnancy (HDP; including gestational hypertension [GH] and pre-eclampsia) and to explore the influence of certain factors on the outcome.

STUDY DESIGN

Meta-analysis was used to quantitatively synthesize the results of similar independent studies.

METHODS

Original documents were identified by searching six electronic bibliographic databases from their inceptions to August 17, 2021. Then we performed meta-analysis to combine the effect estimates if at least three estimates reported the same exposure and outcome and used stratified analysis to evaluate the impact of exposure assessment method, data source, and study area on heterogeneity. In addition, we used the 95% prediction interval to evaluate the potential effects of exposure in random effects meta-analysis.

RESULTS

The overall meta-analysis showed that the risk of HDP was significantly associated with per 5 μg/m³ increase in PM_2.5 exposure during T1 and PM₁₀ exposure during T, with odds ratios [ORs] 1.06 (95% confidence interval [CI]: 1.01-1.12) and 1.04 (95% CI: 1.02-1.07), respectively. The results also showed that PM_2.5 exposure during T1 and T2 and PM₁₀ exposure during T1 increased the incidence of GH; the summary ORs were 1.11 (95% CI: 1.01-1.23), 1.16 (95% CI: 1.05-1.29), and 1.04 (95% CI: 1.02-1.07), respectively. Subgroup analyses showed that the pooled effects were generally significant or more apparent in studies using models to assess exposure, studies whose data derived from birth registers, and studies in Europe.

CONCLUSIONS

This meta-analysis showed that PM exposure was associated with increased HDP risks, and the association varied by study area, data source, and exposure assessment method. With the continuous improvement of research design and exposure assessment, future research may find higher risks.

Dysregulated non-coding telomerase RNA component and associated exonuclease XRN1 in leucocytes from women developing preeclampsia-possible link to enhanced senescence

Senescence in placenta/fetal membranes is a normal phenomenon linked to term parturition. However, excessive senescence which may be induced by telomere attrition, has been associated with preeclampsia (PE). We hypothesized that the telomerase complex in peripheral blood mononuclear cells (PBMC) and circulating telomere associated senescence markers would be dysregulated in women with PE. We measured long non-coding (nc) RNA telomerase RNA component (TERC) and RNAs involved in the maturation of TERC in PBMC, and the expression of TERC and 5′–3′ Exoribonuclease 1 (XRN1) in extracellular vesicles at 22–24 weeks, 36–38 weeks and, 5-year follow-up in controls and PE. We also measured telomere length at 22–24 weeks and 5-year follow-up. The circulating senescence markers cathelicidin antimicrobial peptide (CAMP), β-galactosidase, stathmin 1 (STMN1) and chitotriosidase/CHIT1 were measured at 14–16, 22–24, 36–38 weeks and at 5-year follow-up in the STORK study and before delivery and 6 months post-partum in the ACUTE PE study. We found decreased expression of TERC in PBMC early in pregnant women who subsequently developed PE. XRN1 involved in the maturation of TERC was also reduced in pregnancy and 5-year follow-up. Further, we found that the senescence markers CAMP and β-galactosidase were increased in PE pregnancies, and CAMP remained higher at 5-year follow-up. β-galactosidase was associated with atherogenic lipid ratios during pregnancy and at 5-year follow-up, in PE particularly. This study suggests a potential involvement of dysfunctional telomerase biology in the pathophysiology of PE, which is not restricted to the placenta.

Incidence of pre-eclampsia and other perinatal complications among pregnant women with congenital heart disease: systematic review and meta-analysis

OBJECTIVE

It has been proposed recently that pre-eclampsia (PE) may originate from maternal cardiac maladaptation rather than primary placental insult. As congenital heart disease (CHD) is associated with reduced adaptation to the hemodynamic needs of pregnancy, it is hypothesized that women with CHD have an increased risk of PE. The aim of this systematic review was to investigate the risk of PE in pregnant women with CHD.

METHODS

A systematic search was performed to identify relevant studies published in English, Spanish, French, Italian, Chinese or German, with no time restrictions, using databases such as PubMed, Web of Science and SCOPUS. Randomized controlled trials and observational studies (prospective or retrospective cohorts) of pregnant women with a history of CHD were sought. The main outcome was the incidence of PE (including eclampsia and HELLP syndrome). For quality assessment of the included studies, two reviewers assessed independently the risk of bias. For the meta-analysis, the incidence of PE in pregnancies (those beyond 20 weeks' gestation) was calculated using single-proportion analysis by random-effects modeling (weighted by inverse variance). Heterogeneity between studies was assessed using the χ² (Cochran's Q), tau² and I² statistics. Subgroup analysis was performed, and meta-regression was used to assess the influence of several covariates on the pooled results.

RESULTS

A total of 33 studies were included in the meta-analysis, including 40 449 women with CHD and a total of 40 701 pregnancies. The weighted incidence of PE was 3.1% (95% CI, 2.2-4.0%), with true-effect heterogeneity of 93% according to I² , and no publication bias found. No difference was found in the weighted incidence of PE between studies including cyanotic CHD vs those excluding (or not reporting) cyanotic CHD (2.5% (95% CI, 1.6-3.4%) vs 4.1% (95% CI, 2.4-5.7%); P = 0.0923). Meta-regression analysis showed that the only cofactor that significantly influenced the incidence of PE in each study was the reported incidence of aortic stenosis; studies with a higher incidence of aortic stenosis had a higher incidence of PE (estimate: 0.0005; P = 0.038).

CONCLUSIONS

We failed to demonstrate an incidence of PE above the expected baseline risk in women with CHD. This observation contradicts the theory of the cardiac origin of PE. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

The effect of calcium supplementation on blood pressure in non-pregnant women with previous pre-eclampsia: A randomized placebo-controlled study

BACKGROUND

Low dietary calcium is associated with the hypertensive disorders of pregnancy, and evidence suggests that the risks associated with pre-eclampsia are reduced by calcium supplementation. In the general (non-pregnant) population, low dietary calcium intake is associated with hypertension with inconsistent evidence that calcium supplementation may reduce blood pressure. Women with pre-eclampsia are also at risk of hypertension later in life. An exploratory sub-study among early participants enrolled in the WHO long-term calcium supplementation in women at high risk of pre-eclampsia (CAP) study reported a trend to more blood pressure reduction with calcium in non-pregnant women with previous severe as opposed to non-severe pre-eclampsia. The current study reports the effects of low-dose calcium supplementation in non-pregnant women in the complete trial cohort.

METHODS

The CAP Study was a multi-country randomized, double-blind placebo-controlled clinical trial to test the hypothesis that calcium deficiency may play a role in the genesis of pre-eclampsia in early pregnancy. From 2011 to 2016, non-pregnant women who had pre-eclampsia or eclampsia in their most recent pregnancy were randomized to receive either 500 mg/day elemental calcium or placebo. In this sub-study we compared the change in blood pressure from baseline to the 12-week visit between participants receiving calcium versus placebo for those not pregnant at the 12-week visit.

RESULTS

Of 1355 women randomized, 810 attended a 12-week visit without being pregnant, of whom 791 had blood pressure measurements available for both baseline and 12-week visits. There was a greater reduction in blood pressure in the calcium group compared with the placebo group for systolic pressure (difference 3.1 mmHg, 95% CI 0.8 to 5.4) and mean arterial pressure (MAP) (difference 2.0 mmHg, 95% CI 0.1 to 3.8). The difference in diastolic blood pressure reduction (1.4 mmHg, 95% CI -0.5 to 3.3) was not statistically significant (p = 0.140). For women with previous pre-eclampsia with severe features (n = 447), there was significantly greater reduction in blood pressure in the calcium than the placebo group (difference for systolic 4.0, 95% CI 0.7 to 7.3; diastolic 3.0, 95% CI 0.5 to 5.5 and mean arterial pressure 3.3, 95% CI 0.8 to 5.9 mmHg). For women with previous pre-eclampsia without severe features (n = 344), there were no significant differences between calcium and placebo groups. ANOVA analysis found no statistically significant interaction between previous pre-eclampsia severity and treatment, for systolic (p = 0.372), diastolic (p = 0.063) or mean blood pressure (p = 0.103).

CONCLUSIONS

Low-dose calcium supplementation significantly reduced systolic and mean arterial pressure in non-pregnant women with previous pre-eclampsia. We did not confirm a greater calcium effect in women with previous pre-eclampsia with severe versus non-severe features. The effect of low-dose calcium is of importance since even modest blood pressure reductions at a population level may have important benefits in terms of reduced major complications of hypertension. This study adds to the mounting evidence of health benefits which could be achieved for populations with low dietary calcium through strategies to increase calcium intake, particularly among women at high risk due to previous pre-eclampsia.

CLINICAL TRIAL REGISTRATION

The trial was registered with the Pan-African Clinical Trials Registry, registration number PACTR201105000267371 (https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=267).

Cardiovascular and cerebrovascular health after pre-eclampsia: the Motherhealth prospective cohort study protocol

INTRODUCTION

Cardiovascular and cerebrovascular diseases (CCVDs) are the leading cause of maternal mortality in the first year after delivery. Women whose pregnancies were complicated by pre-eclampsia are at particularly high risk for adverse events. In addition, women with a history of pre-eclampsia have higher risk of CCVD later in life. The physiological mechanisms that contribute to increased CCVD risk in these women are not well understood, and the optimal clinical pathways for postpartum CCVD risk reduction are not yet defined.

METHODS AND ANALYSIS

The Motherhealth Study (MHS) is a prospective cohort study at Columbia University Irving Medical Center (CUIMC), a quaternary care academic medical centre serving a multiethnic population in New York City. MHS began recruitment on 28 September 2018 and will enrol 60 women diagnosed with pre-eclampsia with severe features in the antepartum or postpartum period, and 40 normotensive pregnant women as a comparison cohort. Clinical data, biospecimens and measures of vascular function will be collected from all participants at the time of enrolment. Women in the pre-eclampsia group will complete an additional three postpartum study visits over 12-24 months. Visits will include additional detailed cardiovascular and cerebrovascular phenotyping. As this is an exploratory, observational pilot study, only descriptive statistics are planned. Data will be used to inform power calculations for future planned interventional studies.

ETHICS AND DISSEMINATION

The CUIMC Institutional Review Board approved this study prior to initiation of recruitment. All participants signed informed consent prior to enrolment. Results will be disseminated to the clinical and research community, along with the public, on completion of analyses. Data will be shared on reasonable request.

Nuclear magnetic resonance-based metabolomic analysis in the assessment of preclinical atherosclerosis in type 1 diabetes and preeclampsia

AIMS

Evaluate the role of plasma metabolomics in atherosclerosis according to the presence of type 1 diabetes (T1D) or previous preeclampsia.

METHODS

We recruited 105 women without cardiovascular disease and last pregnancy ≥5 years previously, divided according to the presence of T1D or previous preeclampsia. Preclinical atherosclerosis was defined as the presence of carotid plaque (intima-media thickness ≥1.5 mm) assessed by ultrasonography. Metabolomics were evaluated by nuclear magnetic resonance (NMR). Bivariate and multivariate-adjusted differences in NMR-metabolomics were evaluated.

RESULTS

The participants were 44.9 ± 8.1 years-old; 20% harbored plaques. There were significant differences in lipidic-, energetic- and nitrogen-related metabolites according to the presence of T1D/preeclampsia (p < 0.05). In multivariate-adjusted models (by age, statins, blood pressure and T1D/preeclampsia), only lipidomic-related metabolites were associated with atherosclerosis in the whole sample. However, stronger associations were observed in women with previous preeclampsia (vs. without; per 0.5 mmol/L increments); phosphatidylcholine, OR 4.08 (1.32-27.22); free cholesterol, 5.18 (1.22-21.97); saturated fatty acids, OR 2.99 (1.37-6.48); w-7, OR 2.29 (1.15-4.56); and w-9 fatty acids, OR 1.49 (1.00-2.23).

CONCLUSIONS

NMR-metabolomics showed a differential pattern according to the presence of T1D/preeclampsia in relation to preclinical atherosclerosis. Since most of these metabolites mirror lifestyle factors, they could help tailor dietetic advice in high-risk women.