Preterm birth and future risk of maternal cardiovascular disease - is the association independent of smoking during pregnancy?

Influence of Socioeconomic Status on the Association Between Pregnancy Complications and Premature Coronary Artery Disease: Linking Three Cohorts

Background

We hypothesized that there is an influence of socioeconomic status (SES) on association between pregnancy complications and premature coronary artery disease (PCAD) risk.

Materials and Methods

This project involved a data linkage approach merging three databases of South Australian cohorts using retrospective, age-matched case-control study design. Cases (n = 721), that is, women aged <60 years from Coronary Angiogram Database of South Australia (CADOSA) were linked to South Australian Perinatal Statistics Collection (SAPSC) to ascertain prior pregnancy outcomes and SES. Controls (n = 194) were selected from North West Adelaide Health Study (NWAHS), comprising women who were healthy or had health conditions unrelated to CAD, age matched to CADOSA (±5 years), and linked to SAPSC to determine prior pregnancy outcomes and SES. This project performed comparative analysis of SES using socioeconomic indexes for areas-index of relative socioeconomic advantage and disadvantage (SEIFA-IRSAD) scores across three databases.

Results

Findings revealed that SEIFA-IRSAD scores at the time of pregnancy (p-value = 0.005) and increase in SEIFA-IRSAD scores over time (p-value = 0.040) were significantly associated with PCAD. In addition, when models were adjusted for SEIFA-IRSAD scores at the time of pregnancy and age, risk factors including placenta-mediated pregnancy complications such as preterm birth (odds ratio [OR] = 4.77, 95% confidence interval [CI]: 1.74-13.03) and history of a miscarriage (OR = 2.14, 95% CI: 1.02-4.49), and cardiovascular disease (CVD) risk factors including smoking (OR = 8.60, 95% CI: 3.25-22.75) were significantly associated with PCAD. When the model was adjusted for change in SEIFA-IRSAD scores (from CADOSA/NWAHS to SAPSC) and age, pregnancy-mediated pregnancy complications including preterm birth (OR = 4.40, 95% CI: 1.61-12.05) and history of a miscarriage (OR = 2.09, 95% CI: 1.00-4.35), and CVD risk factor smoking (OR = 8.75, 95% CI: 3.32-23.07) were significantly associated with PCAD.

Conclusion

SES at the time of pregnancy and change in SES were not associated with PCAD risk.

Clinical Pathway for Coronary Atherosclerosis in Patients Without Conventional Modifiable Risk Factors: JACC State-of-the-Art Review

Reducing the incidence and prevalence of standard modifiable cardiovascular risk factors (SMuRFs) is critical to tackling the global burden of coronary artery disease (CAD). However, a substantial number of individuals develop coronary atherosclerosis despite no SMuRFs. SMuRFless patients presenting with myocardial infarction have been observed to have an unexpected higher early mortality compared to their counterparts with at least 1 SMuRF. Evidence for optimal management of these patients is lacking. We assembled an international, multidisciplinary team to develop an evidence-based clinical pathway for SMuRFless CAD patients. A modified Delphi method was applied. The resulting pathway confirms underlying atherosclerosis and true SMuRFless status, ensures evidence-based secondary prevention, and considers additional tests and interventions for less typical contributors. This dedicated pathway for a previously overlooked CAD population, with an accompanying registry, aims to improve outcomes through enhanced adherence to evidence-based secondary prevention and additional diagnosis of modifiable risk factors observed.

Preterm Delivery and Increased Risk of Recurrent Cardiovascular Events in Australian Women

Background: Women with a history of preterm delivery (PTD) have significantly increased risk of experiencing cardiovascular disease (CVD) later in life. However, the risk of long-term recurrence of CVD in this population remains unknown. Materials and Methods: The study was based on a cohort of Victorian women who had a singleton birth between 1999 and 2008. The primary outcome was a CVD event resulting in an Emergency Department visit/hospitalization or death. Women who do not have a PTD during the study period were adopted as the comparator. The Andersen and Gill model, which generalizes the Cox proportional hazards regression model, was used for the analysis of recurrent CVD, while adjusting for covariates, including indigenous status. Results: After excluding cases not meeting the inclusion criteria, 34,128 Victoria women who had a history of PTD and 374,538 women who had deliveries at terms were analyzed. A history of PTD was shown to be associated with significantly increased risk of recurrent CVD, while adjusting for all covariates, including indigenous status, with an adjusted hazard ratio (aHR) of 1.70 (95% confidence interval [CI]: 1.54-1.86, p < 0.0001). Aboriginal and Torres Strait Islander women had substantially increased risk of experiencing recurrent CVD after birth over their lifetime (aHR: 3.22, 95% CI: 2.39-4.35, p < 0.0001). Conclusions: Recognizing PTD as a nontraditional risk factor of CVD may play a role in the formulation of care plans for primary and secondary CVD prevention in women with such a history.

First Trimester Prediction of Preterm Delivery in the Absence of Other Pregnancy-Related Complications Using Cardiovascular-Disease Associated MicroRNA Biomarkers

The aim of the study was to determine if aberrant expression profile of cardiovascular disease associated microRNAs would be able to predict within 10 to 13 weeks of gestation preterm delivery such as spontaneous preterm birth (PTB) or preterm prelabor rupture of membranes (PPROM) in the absence of other pregnancy-related complications (gestational hypertension, preeclampsia, fetal growth restriction, or small for gestational age). In addition, we assessed if aberrant expression profile of cardiovascular disease associated microRNAs would be able to predict preterm delivery before and after 34 weeks of gestation. The retrospective study was performed within the period November 2012 to March 2020. Whole peripheral blood samples were collected from 6440 Caucasian individuals involving 41 PTB and 65 PPROM singleton pregnancies. A control group, 80 singleton term pregnancies, was selected on the base of equal sample storage time. Gene expression of 29 selected cardiovascular disease associated microRNAs was studied using real-time RT-PCR. Downregulation of miR-16-5p, miR-20b-5p, miR-21-5p, miR-24-3p, miR-26a-5p, miR-92a-3p, miR-126-3p, miR-133a-3p, miR-145-5p, miR-146a-5p, miR-155-5p, miR-210-3p, miR-221-3p and miR-342-3p was observed in pregnancies with preterm delivery before 37 (≤36 + 6/7) weeks of gestation. Majority of downregulated microRNAs (miR-16-5p, miR-24-3p, miR-26a-5p, miR-92a-3p, miR-133a-3p, miR-145-5p, miR-146a-5p, miR-155-5p, miR-210-3p, and miR-342-3p) was associated with preterm delivery occurring before 37 (≤36 + 6/7) weeks of gestation. The only miR-210-3p was downregulated in pregnancies with preterm delivery before 34 (≤33 + 6/7) weeks of gestation. The type of preterm delivery also had impact on microRNA gene expression profile. Downregulation of miR-24-3p, miR-92a-3p, miR-155-5p, and miR-210-3p was a common feature of PTB and PPROM pregnancies. Downregulation of miR-16-5p, miR-20b-5p, miR-26a-5p, miR-126-3p, miR-133a-3p, miR-146a-5p, miR-221-3p, and miR-342-3p appeared just in PTB pregnancies. No microRNA was uniquely dysregulated in PPROM pregnancies. The combination of 12 microRNAs (miR-16-5p, miR-20b-5p, miR-21-5p, miR-24-3p, miR-26a-5p, miR-92a-3p, miR-133a-3p, miR-145-5p, miR-146a-5p, miR-155-5p, miR-210-3p, and miR-342-3p, AUC 0.818, p < 0.001, 74.53% sensitivity, 75.00% specificity, cut off > 0.634) equally as the combination of 6 microRNAs (miR-16-5p, miR-21-5p, miR-24-3p, miR-133a-3p, miR-155-5p, and miR-210-3p, AUC 0.812, p < 0.001, 70.75% sensitivity, 78.75% specificity, cut off > 0.652) can predict preterm delivery before 37 weeks of gestation in early stages of gestation in 52.83% pregnancies at 10.0% FPR. Cardiovascular disease associated microRNAs represent promising biomarkers with very good diagnostical potential to be implemented into the current routine first trimester screening programme to predict preterm delivery.

Pre-term delivery and long-term risk of heart failure in women: a national cohort and co-sibling study

AIMS

Women who deliver pre-term have higher future risks of hypertension and ischaemic heart disease, but long-term risks of heart failure (HF) are unknown. We examined these risks in a large national cohort.

METHODS AND RESULTS

All 2 201 284 women with a singleton delivery in Sweden during 1973-2015 were followed up for inpatient or outpatient HF diagnoses through 2015. Cox regression was used to compute hazard ratios (HRs) for HF associated with pregnancy duration, adjusting for other maternal factors. Co-sibling analyses assessed for confounding by shared familial (genetic and/or environmental) factors. In 48.2 million person-years of follow-up, 19 922 women were diagnosed with HF (median age: 60.7 years). Within 10 years after delivery, the adjusted HR was 2.96 [95% confidence interval (CI): 2.48-3.53] for HF associated with pre-term (gestational age: <37 weeks) compared with full-term (39-41 weeks) delivery. Stratified HRs were 4.27 (2.54-7.17) for extremely pre-term (22-27 weeks), 3.39 (2.57-4.48) for moderately pre-term (28-33 weeks), 2.70 (2.19-3.32) for late pre-term (34-36 weeks), and 1.70 (1.45-1.98) for early term (37-38 weeks). These HRs declined but remained elevated at 10-19 years (pre-term vs. full term: HR: 2.19; 95% CI: 1.94-2.46), 20-29 years (1.80; 1.67-1.95), and 30-43 years (1.56; 1.47-1.66) after delivery, and were not explained by shared familial factors.

CONCLUSION

Pre-term and early term delivery were associated with markedly increased future hazards for HF, which persisted after adjusting for other maternal and familial factors and remained elevated 40 years later. Pre-term and early-term delivery should be recognized as risk factors for HF across the life course.

KEY QUESTION

What are the long-term hazards for heart failure (HF) across the life course in women who deliver preterm?

KEY FINDING

Preterm and early term delivery were associated with ∼3- and 1.7-fold adjusted hazards for HF in the next 10 years vs. full-term delivery. These hazards declined but remained elevated 40 years later, and were not explained by shared familial factors.

TAKE HOME MESSAGE

Preterm and early term delivery were associated with increased future hazards for HF, which persisted for 40 years after adjusting for other maternal and familial factors. Preterm and early term delivery should be recognized as lifelong risk factors for HF.

Patterns of Cardiovascular Risk Factors in the Years Before Pregnancy in Nulliparous Women With and Without Preterm Birth and Small-for-Gestational-Age Delivery

Background Women with either preterm or small-for-gestational-age (SGA) delivery have an elevated lifetime risk of cardiovascular disease that has been attributed to the accrual of vascular risk factors over time. We sought to determine whether an adverse cardiovascular risk factor profile develops in the years before pregnancies complicated by preterm delivery or SGA. Methods and Results Using administrative databases, we identified all 156 278 nulliparous women in Ontario, Canada, who had singleton pregnancies between January 2011 and December 2018 and ≥2 measurements of the following analytes between January 2008 and the start of pregnancy: glycosylated hemoglobin, glucose, lipids, and alanine aminotransferase. There were 11 078 women with preterm delivery and 19 367 with SGA. The 2 most recent pregravid tests were performed at median 0.6 (interquartile range, 0.3-1.4) and 1.9 (interquartile range, 1.1-3.3) years before pregnancy, respectively. Women with preterm delivery had higher pregravid glycosylated hemoglobin, glucose, low-density lipoprotein cholesterol, triglycerides, and alanine aminotransferase, and lower high-density lipoprotein cholesterol, than those without preterm delivery. In contrast, women with SGA had lower pregravid fasting glucose, random glucose, and triglycerides than those without SGA. In the years before pregnancy, women with preterm delivery had higher annual increases than their peers in glycosylated hemoglobin (0.7-times higher), triglycerides (7.9-times higher), and alanine aminotransferase (2.2-times higher). During this time, fasting glucose increased in women who developed preterm delivery but decreased in their peers. Conclusions An adverse cardiovascular risk factor profile evolves over time in the years before pregnancy complicated by preterm delivery, but does not necessarily precede SGA.

Preterm Delivery and Long-Term Risk of Stroke in Women: A National Cohort and Cosibling Study

BACKGROUND

Stroke has a high burden of disease in women, and adverse pregnancy outcomes have been identified as important risk factors for stroke later in life. However, long-term risks of stroke associated with preterm delivery and whether such risks are attributable to familial confounding are unclear. Such knowledge is needed to improve long-term risk assessment and stroke prevention in women.

METHODS

A national cohort study was conducted of all 2 188 043 women with a singleton delivery in Sweden in 1973 through 2015 who were followed up for stroke identified from nationwide diagnoses through 2015. Cox regression was used to compute adjusted hazard ratios (aHRs) for stroke associated with pregnancy duration, and cosibling analyses assessed for confounding by shared familial (genetic or environmental) factors.

RESULTS

In 48.0 million person-years of follow-up, 36 372 (1.7%) women were diagnosed with stroke. In the 10 years after delivery, the aHR for stroke associated with preterm delivery (gestational age <37 weeks) was 1.61 (95% CI, 1.45-1.79) and further stratified was 2.81 (95% CI, 2.02-3.91) for extremely preterm (22-27 weeks), 2.07 (95% CI, 1.74-2.46) for very preterm (28-33 weeks), 1.38 (95% CI, 1.21-1.57) for late preterm (34-36 weeks), and 1.15 (95% CI, 1.06-1.24) for early term (37-38 weeks), compared with full-term (39-41 weeks) delivery. These risks remained similarly elevated at 10 to 19 years after delivery (preterm versus full-term: aHR, 1.61 [95% CI, 1.50-1.74]) and then declined but remained significantly elevated at 20 to 29 years (aHR, 1.35 [95% CI, 1.28-1.44]) and 30 to 43 years (aHR, 1.35 [95% CI, 1.27-1.42]). Preterm delivery was associated with both hemorrhagic (aHR, 1.31 [95% CI, 1.25-1.38]) and ischemic (aHR, 1.54 [95% CI, 1.47-1.61]) stroke across the entire follow-up period (up to 43 years). These findings were not explained by shared determinants of preterm delivery and stroke within families. Stroke risks were higher after either spontaneous or medically indicated preterm delivery, and recurrent preterm delivery was associated with further increases in risk.

CONCLUSIONS

In this large national cohort, preterm delivery was associated with higher future risks of both hemorrhagic and ischemic stroke. These associations remained substantially elevated at least 40 years later, and were largely independent of covariates and shared familial factors. Preterm delivery should be recognized as a risk factor for stroke in women across the life course.

A History of Preterm Delivery Is Associated with Aberrant Postpartal MicroRNA Expression Profiles in Mothers with an Absence of Other Pregnancy-Related Complications

This prospective cross-sectional case-control study investigated the postpartal gene expression of microRNAs associated with diabetes/cardiovascular/cerebrovascular diseases in the peripheral white blood cells of women with anamnesis of preterm prelabor rupture of membranes (n = 58), spontaneous preterm birth (n = 55), and term delivery (n = 89) by a quantitative reverse transcription polymerase chain reaction. After pregnancies complicated by preterm prelabor rupture of membranes or spontaneous preterm birth, mothers showed diverse expression profiles for 25 out of 29 tested microRNAs (miR-1-3p, miR-16-5p, miR-17-5p, miR-20a-5p, miR-20b-5p, miR-21-5p, miR-23a-3p, miR-24-3p, miR-26a-5p, miR-29a-3p, miR-100-5p, miR-103a-3p, miR-125b-5p, miR-126-3p, miR-130b-3p, miR-133a-3p, miR-143-3p, miR-145-5p, miR-146a-5p, miR-181a-5p, miR-195-5p, miR-199a-5p, miR-221-3p, miR-499a-5p, and miR-574-3p). The earliest gestational ages at delivery and the lowest birth weights of newborns were associated with the highest postpartal levels of the previously mentioned microRNAs in maternal peripheral white blood cells. Administration of tocolytic drugs in order to prolong pregnancy, used in order to administer and complete a full course of antenatal corticosteroids, was associated with alterations in postpartal microRNA expression profiles to a lesser extent than in women with imminent delivery, where there was insufficient time for administration of tocolytics and antenatal corticosteroids. Overall, mothers who did not receive tocolytic therapy (miR-24-3p and miR-146a-5p) and mothers who did not receive corticosteroid therapy (miR-1-3p, miR-100-5p, and miR-143-3p) had increased or showed a trend toward increased postpartal microRNA expression when compared with mothers given tocolytic and corticosteroid therapy. In addition, mothers with serum C-reactive protein levels above 20 mg/L, who experienced preterm labour, showed a trend toward increased postpartal expression profiles of miR-143-3p and miR-199a-5p when compared with mothers with normal serum C-reactive protein levels. On the other hand, the occurrence of maternal leukocytosis, the presence of intra-amniotic inflammation (higher levels of interleukin 6 in the amniotic fluid), and the administration of antibiotics at the time of preterm delivery had no impact on postpartal microRNA expression profiles in mothers with a history of preterm delivery. Likewise, the condition of the newborns at the moment of birth, determined by Apgar scores at 5 and 10 min and the pH of cord arterial blood, had no influence on the postpartal expression profiles of mothers with a history of preterm delivery. These findings may contribute to explaining the increased cardiovascular risk in mothers with anamnesis of preterm delivery, and the greater increase of maternal cardiovascular risk with the decrease of gestational age at delivery. Women with preterm delivery in their anamnesis represent a high-risk group with special needs on a long-term basis, with a need to apply preventive and therapeutic interventions as early as possible.

Pre-Term Delivery and Risk of Ischemic Heart Disease in Women

BACKGROUND

Women who deliver pre-term have been reported to have increased future risks of cardiometabolic disorders. However, their long-term risks of ischemic heart disease (IHD) and whether such risks are due to shared familial factors are unclear. A better understanding of these risks may help improve long-term clinical follow-up and interventions to prevent IHD in women.

OBJECTIVES

The purpose of this study was to determine the long-term risks of IHD in women by pregnancy duration.

METHODS

A national cohort study was conducted of all 2,189,190 women with a singleton delivery in Sweden from 1973 to 2015, who were followed up for IHD through the end of 2015. Cox regression was used to compute adjusted hazard ratios (aHRs) for IHD associated with pregnancy duration, and cosibling analyses assessed the influence of shared familial (genetic and/or environmental) factors.

RESULTS

In 47.5 million person-years of follow-up, 49,955 (2.3%) women were diagnosed with IHD. In the 10 years following delivery, the aHR for IHD associated with pre-term delivery (<37 weeks) was 2.47 (95% confidence interval [CI]: 2.16 to 2.82), and further stratified was 4.04 (95% CI: 2.69 to 6.08) for extremely pre-term (22 to 27 weeks), 2.62 (95% CI: 2.09 to 3.29) for very pre-term (28 to 33 weeks), 2.30 (95% CI: 1.97 to 2.70) for late pre-term (34 to 36 weeks), and 1.47 (95% CI: 1.30 to 1.65) for early-term (37 to 38 weeks), compared with full-term (39 to 41 weeks). These risks declined but remained significantly elevated after additional follow-up (pre-term vs. full-term, 10 to 19 years: aHR: 1.86; 95% CI: 1.73 to 1.99; 20 to 29 years: aHR: 1.52; 95% CI: 1.45 to 1.59; 30 to 43 years: aHR: 1.38; 95% CI: 1.32 to 1.45). These findings did not appear attributable to shared genetic or environmental factors within families. Additional pre-term deliveries were associated with further increases in risk.

CONCLUSIONS

In this large national cohort, pre-term delivery was a strong independent risk factor for IHD. This association waned over time but remained substantially elevated up to 40 years later. Pre-term delivery should be recognized as a risk factor for IHD in women across the life course.

The Role of Sex-Specific Risk Factors in the Risk Assessment of Atherosclerotic Cardiovascular Disease for Primary Prevention in Women

PURPOSE OF REVIEW

Robust evidence is emerging regarding the contribution of sex-specific risk factors to a woman's unique risk of atherosclerotic cardiovascular disease (ASCVD). This review summarizes the available literature regarding the association of sex-specific risk factors and ASCVD in women.

RECENT FINDINGS

The American College of Cardiology and American Heart Association Guidelines recommend estimation of 10-year risk of a first ASCVD event using the 2013 Pooled Cohort Equations. This can be further personalized by identifying sex-specific risk factors present in a woman's history. There are multiple vulnerable periods across a woman's life course that are associated with increased risk of ASCVD. Risk factors across the reproductive life course that have been shown to correlate with higher risk for future ASCVD include early menarche, adverse pregnancy outcomes (such as pre-eclampsia or preterm birth), and early natural or surgical menopause. In addition, certain conditions that are more common among women, including autoimmune diseases, history of chest irradiation, and certain chemotherapies, also need to be considered. Finally, risk assessment can be refined with subclinical disease imaging (coronary calcium score) if there remains uncertainty about clinical management with lipid-lowering therapies for primary prevention after inclusion of these risk enhancers. Risk assessment for ASCVD in women requires a personalized approach that incorporates sex-specific risk factors to guide primary prevention measures, such as lipid-lowering therapies. Coronary calcium score imaging may also help further refine risk assessment, but no clinical trials conducted to date have addressed this question.

How Does Preterm Delivery Contribute to the Increased Burden of Cardiovascular Disease? Quantifying the Economic Impact of Cardiovascular Disease in Women with a History of Preterm Delivery

Background: The association between preterm delivery (PTD) and maternal risk of cardiovascular disease (CVD) was demonstrated, but the economic burden of CVD in these women was unknown. Methods: A Markov microsimulation model, comprising no event, postacute coronary event (ACE, including acute myocardial infarction and unstable angina), poststroke, post-ACE and stroke, postheart failure, and death, was constructed to quantify the CVD burden in women with PTD from 2017 to 2066 using the Australian health care system perspective. Both first-ever and recurrent CVD events were accounted for in the model. Population with PTD histories was sourced from Australian Bureau of Statistics and costs of acute hospitalization and long-term management from government websites. Nonmonetary burden as years of life lost (YLL) was compared between women with and without PTD histories. Both dynamic (i.e., new cohort added every cycle) and static (i.e., population was stabilized) approaches were used to measure the CVD burden, with sensitivity analyses examining the robustness of results. Results: The dynamic model showed the total CVD burden caused by PTD as AUD11.4 billion for the next 50 years and the YLL as 0.34/capita, while the static model generated a cost of AUD4.5 billion and the YLL as 0.52/capita. Long-term management cost was the primary cost determinant (AUD9.4 billion and AUD3.7 billion, respectively) in the two models, with the results most sensitive to the discount rate and time horizon. Conclusions: Considering the substantial economic burden, recognizing PTD as a potential risk factor and encouraging women with PTD histories to participate in primary prevention programs would potentially curb the ever-increasing CVD burden.

Cardiovascular Disease-Related Morbidity and Mortality in Women With a History of Pregnancy Complications

BACKGROUND

Women with a history of certain pregnancy complications are at higher risk for cardiovascular (CVD) disease. However, most clinical guidelines only recommend postpartum follow-up of those with a history of preeclampsia, gestational diabetes mellitus, or preterm birth. This systematic review was undertaken to determine if there is an association between a broader array of pregnancy complications and the future risk of CVD.

METHODS

We systematically searched PubMed, MEDLINE and EMBASE (via Ovid), CINAHL, and the Cochrane Library from inception to September 22, 2017, for observational studies of the association between the hypertensive disorders of pregnancy, placental abruption, preterm birth, gestational diabetes mellitus, low birth weight, small-for-gestational-age birth, stillbirth, and miscarriage and subsequent CVD. Likelihood ratio meta-analyses were performed to generate pooled odds ratios (OR) and 95% intrinsic confidence intervals (ICI).

RESULTS

Our systematic review included 84 studies (28 993 438 patients). Sample sizes varied from 250 to 2 000 000, with a median follow-up of 7.5 years postpartum. The risk of CVD was highest in women with gestational hypertension (OR 1.7; 95% ICI, 1.3-2.2), preeclampsia (OR 2.7; 95% ICI, 2.5-3.0), placental abruption (OR 1.8; 95% ICI, 1.4-2.3), preterm birth (OR 1.6; 95% ICI, 1.4-1.9), gestational diabetes mellitus (OR 1.7; 95% ICI, 1.1-2.5), and stillbirth (OR 1.5; 95% ICI, 1.1-2.1). A consistent trend was seen for low birth weight and small-for-gestational-age birth weight but not for miscarriage.

CONCLUSIONS

Women with a broader array of pregnancy complications, including placental abruption and stillbirth, are at increased risk of future CVD. The findings support the need for assessment and risk factor management beyond the postpartum period.

Cerebrovascular disease after placental abruption: A population-based prospective cohort study

OBJECTIVE

To test whether abruption during pregnancy is associated with long-term cerebrovascular disease by assessing the incidence and mortality from stroke among women with abruption.

METHODS

We designed a population-based prospective cohort study of women who delivered in Denmark from 1978 to 2010. We used data from the National Patient Registry, Causes of Death Registry, and Danish Birth Registry to identify women with abruption, cerebrovascular events, and deaths. The outcomes included deaths resulting from stroke and nonfatal ischemic and hemorrhagic strokes. We fit Cox proportional hazards regression models for stroke outcomes, adjusting for the delivery year, parity, education, and smoking.

RESULTS

The median (interquartile range) follow-up in the nonabruption and abruption groups was 15.9 (7.8-23.8) and 16.2 (9.6-23.1) years, respectively, among 828,289 women with 13,231,559 person-years of follow-up. Cerebrovascular mortality rates were 0.8 and 0.5 per 10,000 person-years among women with and without abruption, respectively (hazard ratio [HR] 1.6, 95% confidence interval [CI] 0.9-3.0). Abruption was associated with increased rates of nonfatal ischemic stroke (HR 1.4, 95% CI 1.1-1.7) and hemorrhagic stroke (HR 1.4, 95% CI 1.1-1.9). The association of abruption and stroke was increased with delivery at <34 weeks, when accompanied by ischemic placental disease, and among women with ≥2 abruptions. These associations are less likely to have been affected by unmeasured confounding.

CONCLUSION

Abruption is associated with increased risk of cerebrovascular morbidity and mortality. Disruption of the hemostatic system manifesting as ischemia and hemorrhage may indicate shared etiologies between abruption and cerebrovascular complications.

Association of Spontaneous Preterm Delivery and Future Maternal Cardiovascular Disease

Cardiovascular disease (CVD) risk factors are well established. However, little is known about a woman's cardiovascular response to pregnancy, which appears to be an early marker of future maternal CVD risk. Spontaneous preterm delivery (sPTD) has been associated with a ≤3-fold increased risk of maternal CVD death later in life compared with having a term delivery. This review focuses on 3 key areas to critically assess the association of sPTD and future maternal CVD risk: (1) CVD risk factors, (2) inflammatory biomarkers of interest, and (3) specific forms of vascular dysfunction, such as endothelial function and arterial stiffness, and mechanisms by which each may be linked to sPTD. The association of sPTD with subsequent future maternal CVD risk suggests that a woman's abnormal response to pregnancy may serve as her first physiological stress test. These findings suggest that future research is needed to understand why women with sPTD may be at risk for CVD to implement effective interventions earlier in a woman's life.

Preterm Delivery and Future Risk of Maternal Cardiovascular Disease: A Systematic Review and Meta-Analysis

Background

Preterm delivery (<37 weeks gestational age) affects 11% of all pregnancies, but data are conflicting whether preterm birth is associated with long‐term adverse maternal cardiovascular outcomes. We aimed to systematically evaluate and summarize the evidence on the relationship between preterm birth and future maternal risk of cardiovascular diseases.

Methods and Results

A systematic search of MEDLINE and EMBASE was performed to identify relevant studies that evaluated the association between preterm birth and future maternal risk of composite cardiovascular disease, coronary heart disease, stroke, and death caused by cardiovascular or coronary heart disease and stroke. We quantified the associations using random effects meta‐analysis. Twenty‐one studies with over 5.8 million women, including over 338 000 women with previous preterm deliveries, were identified. Meta‐analysis of studies that adjusted for potential confounders showed that preterm birth was associated with an increased risk of maternal future cardiovascular disease (risk ratio [RR] 1.43, 95% confidence interval [CI], 1.18, 1.72), cardiovascular disease death (RR 1.78, 95% CI, 1.42, 2.21), coronary heart disease (RR 1.49, 95% CI, 1.38, 1.60), coronary heart disease death (RR 2.10, 95% CI, 1.87, 2.36), and stroke (RR 1.65, 95% CI, 1.51, 1.79). Sensitivity analysis showed that the highest risks occurred when the preterm deliveries occurred before 32 weeks gestation or were medically indicated.

Conclusions

Preterm delivery is associated with an increase in future maternal adverse cardiovascular outcomes, including a 2‐fold increase in deaths caused by coronary heart disease. These findings support the assessment of preterm delivery in cardiovascular risk assessment in women.

Reproductive factors in relation to heart failure in women: A systematic review

BACKGROUND

The biological mechanisms underlying the sex-related differences in risk of heart failure are still not well understood. The aim of this review was to provide an overview of the current evidence on the association between reproductive factors and risk of heart failure in women.

METHODS

A systematic review of the literature was conducted. PubMed and Embase databases were searched for publications on the following reproductive factors as potential risk factors for heart failure in women: age at menarche, duration and frequency of the menstrual cycle, reproductive lifespan, use of contraception, polycystic ovarian syndrome (PCOS), pregnancy characteristics (e.g. parity), pregnancy complications (e.g. preeclampsia), induced abortion, history of breastfeeding, fertility status, use of assisted reproductive methods, hysterectomy, age at menopause, and use of hormone replacement therapy (HRT).

RESULTS

Twenty-one studies were eligible for inclusion. Hypertensive pregnancy disorders, preterm delivery or small-for-gestational-age (SGA) infants, shorter reproductive duration, and early menopause were risk factors for heart failure in women. It was suggested that PCOS, fertility therapy, gestational diabetes, and age at first pregnancy were not related to risk of heart failure, but a potential relation cannot be fully excluded as most studies were not of sufficient quality. Conflicting results were found for the associations between risk of heart failure and hysterectomy, gravidity and parity, and HRT.

CONCLUSION

Although some reproductive factors were considered risk factors for heart failure in women, the results were mostly conflicting or inconclusive. Further research is needed to confirm and expand the current evidence on the association between reproductive factors and risk of heart failure.

Long-Term Effects of Pregnancy Complications on Maternal Health: A Review

Background: Most pregnancy-related medical complications appear to resolve at delivery or shortly thereafter. Common examples are preterm labor, placental abruption, preeclampsia, and gestational diabetes. Women who developed such complications are known to be at increased risk of developing similar complications in future pregnancies. It has recently become evident that these women are at an increased risk of long term medical complications. Methods: A search through scientific publications in English regarding the association of obstetric complications and long-term maternal illness. Results: There is a clear association between various obstetric complications and long-term effects on maternal health. Conclusions: Women with a history of adverse pregnancy outcomes are at increased risk of cardiovascular and metabolic diseases later in life. Data increasingly links maternal vascular, metabolic, and inflammatory complications of pregnancy with an increased risk of vascular disease in later life.

Impact of Immune Deficiency on Remodeling of Maternal Resistance Vasculature 4 Weeks Postpartum in Mice

Pregnancy manifests changes in the vascular and immune systems that persist postpartum (PP), have important implications for future pregnancies, and may modify responses to cardiovascular stress in late life. The association between immune and vascular function and the generation or progression of cardiovascular disease beg the question of whether altered immunity modifies pregnancy-induced changes in the vasculature. Our objective was to compare changes in the function and remodeling of systemic resistance vessels 4 weeks PP in normal C57BL/6 (B6), and immunodeficient mice recombinase 1-deficient/B6 ( Rag1^-/-). Immune deficiency did not change the responsiveness to acetylcholine (ACh) and phenylephrine at baseline but decreased arterial distensibility and increased stiffness PP. Adoptive transfer of CD8 T cells into Rag1^-/- mice decreased the response to ACh while increasing distensibility and wall thickness. When compared to PP Rag1^-/-, vessels from PP CD4-deficient mice, which have B cells and CD8 T cells, but no CD4 cells, show increased distensibility and decreased responsiveness to ACh in a pattern similar to that seen in Rag1^-/- given CD8 T cells prior to mating. These studies suggest a key role for T cell, particularly CD8 T cell, associated factors in the PP remodeling of maternal resistance vessels.

Immune Regulation in Pregnancy: A Matter of Perspective?

The maternal immune system is complex and governed by multiple hormonal and metabolic factors, including those provided to the mother via the fetus. Understanding of the balance between maternal tolerance and protection of the fetus may require thinking from multiple theoretical approaches to the general problem of immune activation and tolerance. This article provides a brief review of the immune system, with aspects relevant to pregnancy. The references include reviews that expand on the elements discussed. The article also uses different models of immune system activation and tolerance to provide a theoretical understanding of the problem of maternal tolerance.

Immune Regulation in Pregnancy: A Matter of Perspective?

The maternal immune system is complex and governed by multiple hormonal and metabolic factors, including those provided to the mother via the fetus. Understanding of the balance between maternal tolerance and protection of the fetus may require thinking from multiple theoretical approaches to the general problem of immune activation and tolerance. This article provides a brief review of the immune system, with aspects relevant to pregnancy. The references include reviews that expand on the elements discussed. The article also uses different models of immune system activation and tolerance to provide a theoretical understanding of the problem of maternal tolerance.