Association of Pregnancy Complications and Characteristics With Future Risk of Elevated Blood Pressure: The Västerbotten Intervention Program

Predictive Modeling of Hypertension-Related Postpartum Readmission: Retrospective Cohort Analysis

BACKGROUND

Hypertension is the most common reason for postpartum hospital readmission. Better prediction of postpartum readmission will improve the health care of patients. These models will allow better use of resources and decrease health care costs.

OBJECTIVE

This study aimed to evaluate clinical predictors of postpartum readmission for hypertension using a novel machine learning (ML) model that can effectively predict readmissions and balance treatment costs. We examined whether blood pressure and other measures during labor, not just postpartum measures, would be important predictors of readmission.

METHODS

We conducted a retrospective cohort study from the PeriData website data set from a single midwestern academic center of all women who delivered from 2009 to 2018. This study consists of 2 data sets; 1 spanning the years 2009-2015 and the other spanning the years 2016-2018. A total of 47 clinical and demographic variables were collected including blood pressure measurements during labor and post partum, laboratory values, and medication administration. Hospital readmissions were verified by patient chart review. In total, 32,645 were considered in the study. For our analysis, we trained several cost-sensitive ML models to predict the primary outcome of hypertension-related postpartum readmission within 42 days post partum. Models were evaluated using cross-validation and on independent data sets (models trained on data from 2009 to 2015 were validated on the data from 2016 to 2018). To assess clinical viability, a cost analysis of the models was performed to see how their recommendations could affect treatment costs.

RESULTS

Of the 32,645 patients included in the study, 170 were readmitted due to a hypertension-related diagnosis. A cost-sensitive random forest method was found to be the most effective with a balanced accuracy of 76.61% for predicting readmission. Using a feature importance and area under the curve analysis, the most important variables for predicting readmission were blood pressures in labor and 24-48 hours post partum increasing the area under the curve of the model from 0.69 (SD 0.06) to 0.81 (SD 0.06), (P=.05). Cost analysis showed that the resulting model could have reduced associated readmission costs by US $6000 against comparable models with similar F1-score and balanced accuracy. The most effective model was then implemented as a risk calculator that is publicly available. The code for this calculator and the model is also publicly available at a GitHub repository.

CONCLUSIONS

Blood pressure measurements during labor through 48 hours post partum can be combined with other variables to predict women at risk for postpartum readmission. Using ML techniques in conjunction with these data have the potential to improve health outcomes and reduce associated costs. The use of the calculator can greatly assist clinicians in providing care to patients and improve medical decision-making.

Patterns of Gestational Hypertension or Preeclampsia Across 2 Pregnancies in Relationship to Chronic Hypertension Development: A Retrospective Cohort Study

BACKGROUND

Gestational hypertension (GHTN) and preeclampsia are established risk indicators for chronic hypertension. While recurrence is associated with a greater risk, it is unclear whether there are differences in risk when these gestational complications occur for the first time in an earlier pregnancy versus first occurrence in a subsequent one. We hypothesized that the absence of recurrence reflects a transition toward a lower hypertension risk trajectory, whereas a new occurrence in a later pregnancy indicates a transition toward elevated risk.

METHODS AND RESULTS

We analyzed linked data in Quebec, Canada, from public health care insurance administrative databases and birth, stillbirth, and death registries. Our retrospective cohort study included mothers with 2 singleton deliveries between April 1990 and December 2012. The primary exposure was patterns of GHTN or preeclampsia across 2 pregnancies (GHTN/preeclampsia in neither, first only, second only, or both). The outcome was incident chronic hypertension. We performed an adjusted multivariable Cox regression analysis. Among 431 980 women with 2 singleton pregnancies, 27 755 developed hypertension during the follow-up period. Compared with those without GHTN/preeclampsia, those with GHTN/preeclampsia only in the first pregnancy had a 2.7-fold increase in hazards (95% CI, 2.6-2.8), those with GHTN/preeclampsia only in the second had a 4.9-fold increase (95% CI, 4.6-5.1), and those with GHTN/preeclampsia in both pregnancies experienced a 7.3-fold increase (95% CI, 6.9-7.6). Patterns and estimates were similar when we considered GHTN and preeclampsia separately.

CONCLUSIONS

The magnitude of hypertension risk is associated with the number and sequence of GHTN/preeclampsia-affected pregnancies. Considering both allows more personalized risk estimates.

Association Between Gestational Diabetes Mellitus and Hypertension: A Systematic Review and Meta-Analysis of Cohort Studies With a Quantitative Bias Analysis of Uncontrolled Confounding

BACKGROUND

Whether individuals with gestational diabetes mellitus (GDM) had an increased risk of hypertension remains unclear. We conducted a systematic literature review and meta-analysis to examine the association between GDM and hypertension and performed a quantitative bias analysis to quantify the impact of uncontrolled confounding due to antenatal psychological stress.

METHODS

We searched databases (PUBMED, EMBASE, and Web of Science) through 2022/11. Eligible studies were cohort studies that reported the association of GDM with hypertension. We assessed the risk of bias using the Newcastle-Ottawa Scale for cohort studies. We pooled adjusted risk ratios with 95% CIs using a random effects model. We performed the quantitative bias analysis using the bias formula.

RESULTS

We included 15 cohort studies, with a total of 3 959 520 (GDM, 175 378; non-GDM, 3 784 142) individuals. During the follow-up of 2 to 20 years, 106 560 cases of hypertension were reported. We found that GDM was associated with a higher risk of hypertension (pooled risk ratio, 1.78 [95% CI, 1.47, 2.17]). The risk ratio was lower among cohorts assessing incident (1.58 [95% CI, 1.29, 1.95]) than prevalent hypertension (2.60 [95% CI, 2.40, 2.83]). However, other subgroup analyses showed no differences. The quantitative bias analysis revealed that if the uncontrolled confounder of antenatal psychological stress was additionally adjusted, the positive association between GDM and hypertension would attenuate slightly (≤18%) but remains positive.

CONCLUSIONS

Limitations of this study included residual confounding and discrepancies in GDM and hypertension ascertainments. Our findings indicate that GDM is positively associated with hypertension after the index pregnancy.

Risk of adverse pregnancy outcomes in twin- and singleton-born women: An inter-generational cohort study

OBJECTIVE

To compare the risk of adverse pregnancy outcomes between twin-born and singleton-born women. We also evaluated whether in utero exposure to pre-eclampsia or preterm delivery affected adverse pregnancy outcomes in women's own pregnancies.

DESIGN

Population-based cohort study.

SETTING

Medical Birth Registry of Norway 1967-2020.

POPULATION

9184 twin-born and 492 894 singleton-born women during 1967-2005, with their later pregnancies registered during 1981-2020.

METHODS

Data from an individual's birth were linked to their later pregnancies. We used generalised linear models with log link binomial distribution to obtain exponentiated regression coefficients that estimated relative risks (RRs) with 95% confidence intervals (CIs) for associations between twin- or singleton-born women and later adverse pregnancy outcomes.

MAIN OUTCOME MEASURES

Pre-eclampsia, preterm delivery or perinatal loss in twin-born compared with singleton-born women.

RESULTS

There was no increased risk for adverse outcomes in twin-born compared with singleton-born women: adjusted RRs for pre-eclampsia were 1.00 (95% CI 0.93-1.09), for preterm delivery 0.96 (95% CI 0.90-1.02) and for perinatal loss 1.00 (95% CI 0.84-1.18). Compared with singleton-born women exposed to pre-eclampsia in utero, twin-born women exposed to pre-eclampsia had lower risk of adverse outcomes in their own pregnancies; the aRR for pre-eclampsia was 0.73 (95% CI 0.58-0.91) and for preterm delivery was 0.71 (95% CI 0.56-0.90). Compared with preterm singleton-born women, preterm twin-born women did not differ in terms of risk of pre-eclampsia (aRR 1.05, 95% CI 0.92-1.21) or perinatal loss (aRR 0.99, 95% CI 0.71-1.37) and had reduced risk of preterm delivery (RR 0.83, 95% CI 0.74-0.94).

CONCLUSIONS

Twin-born women did not differ from singleton-born women in terms of risk of adverse pregnancy outcomes. Twin-born women exposed to pre-eclampsia in utero, had a lower risk of pre-eclampsia and preterm delivery compared with singleton-born women exposed to pre-eclampsia.

Update on sex specific risk factors in cardiovascular disease

Cardiovascular disease (CVD) is the leading cause of death worldwide and accounts for roughly 1 in 5 deaths in the United States. Women in particular face significant disparities in their cardiovascular care when compared to men, both in the diagnosis and treatment of CVD. Sex differences exist in the prevalence and effect of cardiovascular risk factors. For example, women with history of traditional cardiovascular risk factors including hypertension, tobacco use, and diabetes carry a higher risk of major cardiovascular events and mortality when compared to men. These discrepancies in terms of the relative risk of CVD when traditional risk factors are present appear to explain some, but not all, of the observed differences among men and women. Sex-specific cardiovascular disease research-from identification, risk stratification, and treatment-has received increasing recognition in recent years, highlighting the current underestimated association between CVD and a woman's obstetric and reproductive history. In this comprehensive review, sex-specific risk factors unique to women including adverse pregnancy outcomes (APO), such as hypertensive disorders of pregnancy (HDP), gestational diabetes mellitus, preterm delivery, and newborn size for gestational age, as well as premature menarche, menopause and vasomotor symptoms, polycystic ovarian syndrome (PCOS), and infertility will be discussed in full detail and their association with CVD risk. Additional entities including spontaneous coronary artery dissection (SCAD), coronary microvascular disease (CMD), systemic autoimmune disorders, and mental and behavioral health will also be discussed in terms of their prevalence among women and their association with CVD. In this comprehensive review, we will also provide clinicians with a guide to address current knowledge gaps including implementation of a sex-specific patient questionnaire to allow for appropriate risk assessment, stratification, and prevention of CVD in women.

The Risk of Hypertension and Diabetes Mellitus According to Offspring's Birthweight in Women With Normal Body Mass Index: A Nationwide Population-Based Study

BACKGROUND

Maladaptation to vascular, metabolic, and physiological changes during pregnancy can lead to fetal growth disorders. Moreover, adverse outcomes during pregnancy can further increase the risk of cardiovascular and metabolic diseases in mothers. Delivering a large-for-gestational-age (LGA) baby may indicate a pre-existing metabolic dysfunction, whereas delivering a small-for-gestational-age (SGA) baby may indicate a pre-existing vascular dysfunction. This study aims to assess the risk of hypertension (HTN) and diabetes mellitus (DM) in women with normal body mass index (BMI) scores who did not experience gestational DM or hypertensive disorders during pregnancy based on the offspring's birthweight.

METHODS

This retrospective nationwide study included women with normal BMI scores who delivered a singleton baby after 37 weeks. Women with a history of DM or HTN before pregnancy and those with gestational DM or hypertensive disorders, were excluded from the study. We compared the risk of future maternal outcomes (HTN and DM) according to the offspring's birthweight. Multivariate analyses were performed to estimate the hazard ratio (HR) for the future risk of HTN or DM.

RESULTS

A total of 64,037 women were included in the analysis. Of these, women who delivered very LGA babies (birthweight > 97th percentile) were at a higher risk of developing DM than those who delivered appropriate-for-gestational-age (AGA) babies (adjusted HR = 1.358 [1.068-1.727]), and women who delivered very SGA babies (birthweight < 3rd percentile) were at a higher risk of developing HTN than those who delivered AGA babies (adjusted HR = 1.431 [1.181-1.734]), even after adjusting for age, parity, gestational age at delivery, fetal sex, maternal BMI score, and a history of smoking.

CONCLUSION

These findings provide a novel support for the use of the offspring's birthweight as a predictor of future maternal diseases such as HTN and DM.

Genetic liability to age at first sex and birth in relation to cardiovascular diseases: a Mendelian randomization study

BACKGROUND

Growing evidence suggests that various reproductive factors, including early menarche, early menopause, and age at first birth, may increase the risk of developing cardiovascular disease (CVD) later in life. However, the associations between reproductive factors and CVDs are inconsistent and controversial. Therefore, we conducted a two-sample Mendelian randomization (MR) analysis to explore the potential links between age at first sex (AFS) and age at first birth (AFB) and several CVDs.

METHODS

We obtained summary statistics for exposure from the largest genome-wide association studies of AFS and AFB. To serve as instrumental variables, we selected 259 SNPs associated with AFS and 81 SNPs associated with AFB at the genome-wide significance level. We employed a random-effects inverse-variance weighted method to pool estimates, and conducted multivariable MR analysis to determine the direct association between AFS and AFB with CVDs, while accounting for the effects of confounders.

RESULTS

The genetic liability to later AFS was associated with decreased risks of heart failure (odd ratio [OR] 0.700; 95% confidence interval [CI] 0.639-0.767; p = 2.23 × 10^-14), coronary artery disease (OR 0.728; 95% CI 0.657-0.808; p = 1.82 × 10^-9), myocardial infarction (OR 0.731; 95% CI 0.657-0.813; p = 8.33 × 10^-9), stroke (OR 0.747; 95% CI 0.684-0.816; p = 6.89 × 10^-11), and atrial fibrillation (OR 0.871; 95% CI 0.806-0.941; p = 4.48 × 10^-4). The genetic liability to later AFB was also associated with decreased risks of CVDs, including myocardial infarction (OR 0.895; 95% CI 0.852-0.940; p = 8.66 × 10^-6), coronary heart disease (OR 0.901; 95% CI 0.860-0.943; p = 9.02 × 10^-6), heart failure (OR 0.925; 95% CI 0.891-0.961; p = 5.32 × 10^-5), and atrial fibrillation (OR 0.944; 95% CI 0.911-0.978; p = 0.001). However, no association was found between AFB and stroke. The associations remained independent from the effects of AFS and AFB on potential confounders, including smoking, alcohol intake, body mass index, and depression. Mediation analysis suggested that education attainment partly mediates the link from AFS and AFB to CVD outcomes.

CONCLUSION

Our results observed a causal relationship between later AFS, AFB and lower CVDs risk; it emphasizes the importance of providing sex education since early sex and birth may have undesirable effects. Cardiovascular risk stratification that considers reproductive factors may help address CVD risk.

Breastfeeding and Later-Life Cardiometabolic Health in Women With and Without Hypertensive Disorders of Pregnancy

Background Breastfeeding is associated with improved cardiometabolic profiles decades after pregnancy. Whether this association exists for women who experience hypertensive disorders of pregnancy (HDP) is unknown. The authors examined whether breastfeeding duration or exclusivity are associated with long-term cardiometabolic health, and whether this relationship differs by HDP status. Methods and Results Participants (N=3598) were from the UK ALSPAC (Avon Longitudinal Study of Parents and Children) cohort. HDP status was assessed by medical record review. Breastfeeding behaviors were assessed by contemporaneous questionnaires. Breastfeeding duration was categorized as never, <1, 1 to <3, 3 to <6, 6 to <9, and 9+ months. Breastfeeding exclusivity was categorized as never, <1, 1 to <3, and 3 to 6 months. Measures of cardiometabolic health (body mass index, waist circumference, C-reactive protein, insulin, proinsulin, glucose, lipids, blood pressure, mean arterial pressure, carotid intima-media thickness, and arterial distensibility) were measured 18 years after pregnancy. Analyses were conducted using linear regression adjusting for relevant covariates. Breastfeeding was associated with improved cardiometabolic health (lower body mass index, waist circumference, C-reactive protein, triglycerides, insulin, and proinsulin) in all women, but not for every breastfeeding duration. Interaction tests revealed additional benefits in women with a history of HDP, with the strongest benefit observed in the 6- to 9-month breastfeeding category (diastolic blood pressure, -4.87 mm Hg [95% CI, -7.86 to -1.88], mean arterial pressure -4.61 [95% CI, -7.45 to -1.77], and low-density lipoprotein cholesterol, -0.40 mmol/L [95% CI, -0.62 to -0.17 mmol/L]). Differences in C-reactive protein and low-density lipoprotein "survived" Bonferroni correction (P<0.001). Similar results were observed in the exclusive breastfeeding analyses. Conclusions Breastfeeding may be a mechanism to reduce the cardiovascular disease sequela associated with HDP; however, there is a need to establish whether associations reflect a causal effect.

Long term miscarriage-related hypertension and diabetes mellitus. Evidence from a United Kingdom population-based cohort study

BACKGROUND

Miscarriages affect up to a fifth of all pregnancies and are associated with substantial psychological morbidity. However, their relationship with cardiometabolic risk factors is not well known. Therefore, in this study we aimed to estimate the burden of cardiovascular risk factors including diabetes mellitus (type 1 or 2) and hypertension in women with miscarriage compared to women without a record of miscarriage.

METHODS

A population-based retrospective cohort study was conducted using IVQIA Medical Research Data UK (IMRD-UK) between January 1995 and May 2016, an anonymised electronic health records database that is representative of the UK population. A total of 86,509, 16-50-year-old women with a record of miscarriage (exposed group) were matched by age, smoking status, and body mass index to 329,865 women without a record of miscarriage (unexposed group). Patients with pre-existing hypertension and diabetes were excluded. Adjusted incidence rate ratios (aIRR) and 95% confidence intervals (95% CI) for diabetes and hypertension were estimated using multivariable Poisson regression models offsetting for person-years follow-up.

RESULTS

The mean age at cohort entry was 31 years and median follow up was 4.6 (IQR 1.7-9.4) years. During the study period, a total of 792 (IR 1.44 per 1000 years) and 2525 (IR 1.26 per 1000 years) patients developed diabetes in the exposed and unexposed groups, respectively. For hypertension, 1995 (IR 3.73 per 1000 years) and 1605 (IR 3.39 per 1000 years) new diagnoses were recorded in the exposed and unexposed groups, respectively. Compared to unexposed individuals, women with a record miscarriage were more likely to develop diabetes (aIRR = 1.25, 95% CI: 1.15-1.36; p<0.001) and hypertension (aIRR = 1.07, 95% CI: 1.02-1.12; p = 0.005).

CONCLUSIONS

Women diagnosed with miscarriage were at increased risk of developing diabetes mellitus and hypertension. Women with history of miscarriage may benefit from periodic monitoring of their cardiometabolic health.

Does Adding Adverse Pregnancy Outcomes Improve the Framingham Cardiovascular Risk Score in Women? Data from the Tehran Lipid and Glucose Study

Background Limited and conflicting evidence is available regarding the predictive value of adding adverse pregnancy outcomes (APOs) to established cardiovascular disease (CVD) risk factors. Hence, the objective of this study was to determine whether adding APOs to the Framingham risk score improves the prediction of CVD events in women. Methods and Results Out of 5413 women who participated in the Tehran Lipid and Glucose Study, 4013 women met the eligibility criteria included for the present study. The exposure and the outcome variables were collected based on the standard protocol. Cox proportional hazard model was used to evaluate the association of APOs and CVDs. The variant of C-statistic for survivals and reclassification of subjects into Framingham risk score categories after adding APOs was reported. Out of the 4013 eligible subjects, a total of 1484 (36.98%) women reported 1 APO, while 395 (9.84%) of the cases reported multiple APOs. Univariate proportional hazard Cox models showed the significant relations between CVD events and APOs. The enhanced model had a higher C-statistic indicating more acceptable discrimination as well as a slight improvement in discrimination (C-statistic differences: 0.0053). Moreover, we observed a greater risk of experiencing a CVD event in women with a history of multiple APOs compared with cases with only 1 APO (1 APO: hazard ratio [HR] = 1.22; 2 APOs: HR; 1.94; ≥3 APOs: HR = 2.48). Conclusions Beyond the established risk factors, re-estimated CVDs risk by adding APOs to the Framingham risk score may improve the accurate risk estimation of CVD. Further observational studies are needed to confirm our findings.

Use of Race, Ethnicity, and National Origin in Studies Assessing Cardiovascular Risk in Women With a History of Hypertensive Disorders of Pregnancy

Women with a history of hyperBtensive disorders of pregnancy (HDP) are at particularly high risk for cardiovascular disease (CVD) and CVD-related death, and certain racial and ethnic subpopulations are disproportionately affected by these conditions. We examined the use of race, ethnicity, and national origin in observational studies assessing CVD morbidity and mortality in women with a history of HDP. A total of 124 studies, published between 1976 and 2021, were reviewed. We found that white women were heavily overrepresented, encompassing 53% of all participants with HDP. There was limited and heterogeneous reporting of race and ethnicity information across studies and only 27 studies reported including race and/or ethnicity variables in at least 1 statistical analysis. Only 2 studies mentioned the use of these variables as a strength; several others (k = 18) reported a lack of diversity among participants as a study limitation. Just over half of included articles (k = 68) reported at least 1 sociodemographic variable other than race and ethnicity (eg, marital status and income); however, none investigated how they might have worked synergistically or antagonistically with race and/or ethnicity to influence participants' risk of CVD. These findings highlight significant areas for improvement in cardiovascular obstetrics research, including the need for more robust and standardized methods for collecting, reporting, and using sociodemographic information. Future studies of CVD risk in women with a history of HDP should explicitly examine racial and ethnic differences and use an intersectional approach.

Reproductive History in Takotsubo Syndrome, A Register-Based Cohort Study

Background: Takotsubo syndrome (TS) is a recently recognized serious heart condition that mainly affects women. Despite that 80–90% of the patients are women, few studies have focused on sex-specific characteristics such as female sex hormones and reproductive history. The aim of the study was to compare reproductive history in patients with TS with controls.

Methods: This register-based cohort study compared reproductive history and off-spring birth characteristics between 158 TS patients without coronary artery stenoses and 236 age- and sex-matched controls (C) with coronary artery stenoses because of acute coronary syndrome (ACS-C), respectively, 285 without coronary artery stenoses with chest pain (CP-C).

Results: There were no differences in pregnancy complications between TS and CP-C. Gestational length did not differ, but infants born to TS patients had lower birth weight for gestational age than CP-C with an odds ratio of 1.7 (95% confidence interval 1.2–2.5) for infants born small.

Conclusion: The results showing an association between birth weight for gestational age and TS later in life are hypothesis-generating. The association is not likely causal and before delivery of small for gestational age infants can be considered as a risk marker for TS later in life the results need to be confirmed in independent studies

Death of an offspring and parental risk of ischemic heart diseases: A population-based cohort study

BACKGROUND

The death of a child is an extreme life event with potentially long-term health consequences. Knowledge about its association with ischemic heart diseases (IHDs) and acute myocardial infarction (AMI), however, is very limited. We investigated whether the death of an offspring is associated with the risk of IHD and AMI.

METHODS AND FINDINGS

We studied parents of live-born children recorded in the Danish (1973 to 2016) and the Swedish (1973 to 2014) Medical Birth Registers (n = 6,711,952; mean age at baseline 31 years, 53% women). We retrieved information on exposure, outcomes, and covariates by linking individual-level information from several nationwide registers. We analyzed the abovementioned associations using Poisson regression. A total of 126,522 (1.9%) parents lost at least 1 child during the study period. Bereaved parents had a higher risk of IHD and AMI than the nonbereaved [incidence rate ratios (IRRs) (95% confidence intervals (CIs)): 1.20 (1.18 to 1.23), P < 0.001 and 1.21 (1.17 to 1.25), P < 0.001, respectively]. The association was present not only in case of losses due to CVD or other natural causes, but also in case of unnatural deaths. The AMI risk was highest in the first week after the loss [IRR (95% CI): 3.67 (2.08 to 6.46), P < 0.001], but a 20% to 40% increased risk was observed throughout the whole follow-up period. Study limitations include the possibility of residual confounding by socioeconomic, lifestyle, or health-related factors and the potentially limited generalizability of our findings outside Scandinavia.

CONCLUSIONS

The death of an offspring was associated with an increased risk of IHD and AMI. The finding that the association was present also in case of losses due to unnatural causes, which are less likely to be confounded by cardiovascular risk factors clustering in families, suggests that stress-related mechanisms may also contribute to the observed associations.

Hypertension in women: the role of adolescent childbearing

BACKGROUND

Adolescent childbearing is associated with various health risks to the mother and child, and potentially with adverse socioeconomic outcomes. However, little is known about the role of adolescent childbearing in maternal health outcomes in adulthood. This study investigates the link between childbirth in adolescence and later-life risk of hypertension among women in India.

METHODS

We obtained nationally representative data on demographic and health outcomes for 442,845 women aged 25 to 49 from the India National Family Health Survey (NFHS) 2015-16. We assessed the difference in hypertension prevalence between women who gave birth in adolescence (age 10 to 19) and those who did not, for the full sample and various sub-samples, using linear probability models with controls for individual characteristics, hypertension risk factors, and geographic fixed effects.

RESULTS

Nearly 40% of the women in the sample gave birth in adolescence. The adjusted probability of being hypertensive in adulthood was 2.3 percentage points higher for this group compared to women who did not give childbirth in adolescence. This added probability was larger for women who gave birth earlier in adolescence (4.8 percentage points) and for women who gave birth more than once in adolescence (3.4 percentage points).

CONCLUSIONS

Adolescent childbearing was strongly associated with a higher probability of adult female hypertension in India. This finding illustrates the intertemporal relationship between health risk factors during the life cycle, informing the importance of addressing adverse early life events (e.g. child marriage and adolescent childbirth) for hypertension outcomes among women in India.

The effect of bearing and rearing a child on blood pressure: a nationally representative instrumental variable analysis of 444611 mothers in India

BACKGROUND

At the individual level, it is well known that pregnancies have a short-term effect on a woman's cardiovascular system and blood pressure. The long-term effect of having children on maternal blood pressure, however, is unknown. We thus estimated the causal effect of having children on blood pressure among mothers in India, a country with a history of high fertility rates.

METHODS

We used nationally representative cross-sectional data from the 2015-16 India National Family and Health Survey (NFHS-4). The study population comprised 444 611 mothers aged 15-49 years. We used the sex of the first-born child as an instrumental variable (IV) for the total number of a woman's children. We estimated the effect of an additional child on systolic and diastolic blood pressure in IV (two-stage least squares) regressions. In additional analyses, we stratified the IV regressions by time since a mother last gave birth. Furthermore, we repeated our analyses using mothers' husbands and partners as the regression sample.

RESULTS

On average, mothers had 2.7 children [standard deviation (SD): 1.5], a systolic blood pressure of 116.4 mmHg (SD: 14.4) and diastolic blood pressure of 78.5 mmHg (SD: 9.4). One in seven mothers was hypertensive. In conventional ordinary least squares regression, each child was associated with 0.42 mmHg lower systolic [95% confidence interval (CI): -0.46 to -0.39, P < 0.001] and 0.13 mmHg lower diastolic (95% CI: -0.15 to -0.11, P < 0.001) blood pressure. In the IV regressions, each child decreased a mother's systolic blood pressure by an average of 1.00 mmHg (95% CI: -1.26 to -0.74, P < 0.001) and diastolic blood pressure by an average of 0.35 mmHg (95% CI: -0.52 to -0.17, P < 0.001). These decreases were sustained over more than a decade after childbirth, with effect sizes slightly declining as the time since last birth increased. Having children did not influence blood pressure in men.

CONCLUSIONS

Bearing and rearing a child decreases blood pressure among mothers in India.

The role of multiparity and maternal age at first pregnancy in the association between early menarche and metabolic syndrome among middle-aged and older women

OBJECTIVE

To analyze whether maternal age at first pregnancy and parity are mediators of the association between early menarche and metabolic syndrome in a sample of middle-aged and older women.

METHODS

Cross-sectional study of 428 women (40 to 80 y), who had experienced a pregnancy in their lifetime, was performed between 2014 and 2016. Age at first pregnancy, parity, and early menarche were self-reported. Metabolic syndrome was assessed using the criteria described by the National Cholesterol Education Program's Adult Treatment Panel III. The association between metabolic syndrome and early menarche was assessed by logistic regression analysis. The mediating role of age at first pregnancy and multiparity in the relationship between early menarche and metabolic syndrome was assessed through mediation analysis, adjusted for covariates.

RESULTS

According to adjusted logistic regression models, early menarche was associated with higher odds of prevalent metabolic syndrome (OR: 2.26; 95% CI: 1.15-4.46). Mediation analysis showed a significant direct effect of early menarche on metabolic syndrome (β: 0.808; 95% CI: 0.107-1.508). Of the two mediators tested, age at first pregnancy was significant (β: 0.065; 95% CI: 0.004-0.221), ie, participants with and without early menarche differ, on average, by 0.879 SDs in the log odds of MetS (total effect), of which 0.065 SDs (8%), on average, would be attributable to the effect of early menarche on age at first pregnancy (indirect effect), which, in turn, affects MetS.

CONCLUSIONS

Age at first pregnancy may partially contribute to the association between early menarche and metabolic syndrome among middle-aged and older women who had experienced a pregnancy over their lifetime.

CNN-Based LCD Transcription of Blood Pressure From a Mobile Phone Camera

Routine blood pressure (BP) measurement in pregnancy is commonly performed using automated oscillometric devices. Since no wireless oscillometric BP device has been validated in preeclamptic populations, a simple approach for capturing readings from such devices is needed, especially in low-resource settings where transmission of BP data from the field to central locations is an important mechanism for triage. To this end, a total of 8192 BP readings were captured from the Liquid Crystal Display (LCD) screen of a standard Omron M7 self-inflating BP cuff using a cellphone camera. A cohort of 49 lay midwives captured these data from 1697 pregnant women carrying singletons between 6 weeks and 40 weeks gestational age in rural Guatemala during routine screening. Images exhibited a wide variability in their appearance due to variations in orientation and parallax; environmental factors such as lighting, shadows; and image acquisition factors such as motion blur and problems with focus. Images were independently labeled for readability and quality by three annotators (BP range: 34-203 mm Hg) and disagreements were resolved. Methods to preprocess and automatically segment the LCD images into diastolic BP, systolic BP and heart rate using a contour-based technique were developed. A deep convolutional neural network was then trained to convert the LCD images into numerical values using a multi-digit recognition approach. On readable low- and high-quality images, this proposed approach achieved a 91% classification accuracy and mean absolute error of 3.19 mm Hg for systolic BP and 91% accuracy and mean absolute error of 0.94 mm Hg for diastolic BP. These error values are within the FDA guidelines for BP monitoring when poor quality images are excluded. The performance of the proposed approach was shown to be greatly superior to state-of-the-art open-source tools (Tesseract and the Google Vision API). The algorithm was developed such that it could be deployed on a phone and work without connectivity to a network.

Adverse Pregnancy Outcomes and Cardiovascular Disease Risk: Unique Opportunities for Cardiovascular Disease Prevention in Women: A Scientific Statement From the American Heart Association

This statement summarizes evidence that adverse pregnancy outcomes (APOs) such as hypertensive disorders of pregnancy, preterm delivery, gestational diabetes, small-for-gestational-age delivery, placental abruption, and pregnancy loss increase a woman's risk of developing cardiovascular disease (CVD) risk factors and of developing subsequent CVD (including fatal and nonfatal coronary heart disease, stroke, peripheral vascular disease, and heart failure). This statement highlights the importance of recognizing APOs when CVD risk is evaluated in women, although their value in reclassifying risk may not be established. A history of APOs is a prompt for more vigorous primordial prevention of CVD risk factors and primary prevention of CVD. Adopting a heart-healthy diet and increasing physical activity among women with APOs, starting in the postpartum setting and continuing across the life span, are important lifestyle interventions to decrease CVD risk. Lactation and breastfeeding may lower a woman's later cardiometabolic risk. Black and Asian women experience a higher proportion APOs, with more severe clinical presentation and worse outcomes, than White women. More studies on APOs and CVD in non-White women are needed to better understand and address these health disparities. Future studies of aspirin, statins, and metformin may better inform our recommendations for pharmacotherapy in primary CVD prevention among women who have had an APO. Several opportunities exist for health care systems to improve transitions of care for women with APOs and to implement strategies to reduce their long-term CVD risk. One proposed strategy includes incorporation of the concept of a fourth trimester into clinical recommendations and health care policy.

Impact of prior preterm or term small for gestational age birth on maternal blood pressure during the menopause transition in the Study of Women's Health Across the Nation

OBJECTIVE

To examine whether blood pressure (BP) accelerates more rapidly during the menopause transition for women with a history of preterm or term small for gestational age (SGA) delivery compared to women with all term and appropriate for gestational age (AGA) births.

METHODS

A longitudinal analysis was conducted with 1,008 parous women who had BP data at ≥2 study visits. We used generalized linear modeling to examine BP before the final menstrual period, at the final mentrual period, and up to 10 years after the final menstrual period, according to pregnancy group. We assessed maternal changes in BP over time in relation to years near the final menstrual period using a piece-wise linear model, consistent with menopause-induced changes. Models were adjusted for socio-demographics, body mass index, smoking, physical activity, medications, parity, age at first birth, gestational diabetes, and gestational hypertension/preeclampsia.

RESULTS

At baseline, women were on average 46 years old, 101 (10%) reported a prior preterm birth, and 102 (10.1%) reported a term SGA birth. Compared to women with all term AGA births, women with a term SGA birth had higher BP before the final menstrual period, at the final menstrual period, and up to 10 years after the final menstrual period; women with a preterm birth had higher BP in the postmenopausal years. Annual rate of change in BP during the menopause transition did not differ between pregnancy groups.

CONCLUSIONS

Women with a history preterm and term SGA delivery have higher BP than women with all term AGA births during the menopause transition, but rate of change in BP does not differ in these groups relative to final menstrual period.

Previous preeclampsia and its association with the future development of cardiovascular diseases: a systematic review and meta-analysis

Preeclampsia is a multifactorial disease. Among these factors, untreated hypertension during pregnancy can result in high morbidity and mortality rates and may also be related to the future development of cardiovascular diseases.Therefore, this systematic review aimed to determine the association of previous preeclampsia with the future development of cardiovascular diseases. Studies on the association between preeclampsia and future cardiovascular diseases published in the last 10 years (2009-2019) were identified from the PubMed/Medline (207 articles), Embase (nine articles), and Cochrane (three articles) databases using the keywords "preeclampsia" and "future cardiovascular diseases", "preeclampsia" and "future heart attack", and "preeclampsia" and "future cardiac disease". After applying the inclusion and exclusion criteria, 15 articles were analyzed by systematic review and meta-analysis according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The meta-analysis and the determination of the quality of the articles were conducted using RevMan software, version 5.3. Statistically significant differences were observed between the control and previous preeclampsia groups with respect to systolic blood pressure (mean difference [MD] 4.32; 95% confidence interval [95%CI] 3.65, 4.99; p<0.001), diastolic blood pressure (MD): 2.11; 95%CI: 1.68, 2.55; p<0.0001), and insulin level (MD: 2.80; 95% CI: 0.50, 5.11; p<0.001). Body mass index (MD: 2.57, 95%CI: 2.06, 3.07; p=0.0001), total cholesterol (MD: 10.39; 95%CI: 8.91, 11.87; p=0.0001), HDL (MD: 2.83; 95%CI: 2.20, 3.46; p=0.0001), and LDL (MD: 1.77; 95%CI: 0.42, 3.13; p=0.0001) also differed significantly between groups. Thus, the results of the present study showed that women with a history of preeclampsia were more likely to develop cardiovascular disease.

Maternal risk of hypertension 7-15 years after pregnancy: clues from the placenta

OBJECTIVE

To assess whether pre-eclampsia (PE)-related placental/extraplacental membrane findings are linked to moderately elevated blood pressure (BP) in pregnancy and later-life hypertension.

DESIGN

Prospective cohort.

SETTING

52 prenatal clinics, 5 Michigan communities.

SAMPLE

The POUCH Study recruited women at 16-27 weeks' gestation (1998-2004) and studied a sub-cohort in depth. This sample (n = 490) includes sub-cohort women with detailed placental assessments and cardiovascular health evaluations 7-15 years later in the POUCHmoms follow-up study.

METHODS

PE-related placental/extraplacental membrane findings (i.e. mural hyperplasia, unaltered/abnormal vessels or atherosis in decidua; infarcts) were evaluated in relation to pregnancy BP and odds of Stage 2 hypertension at follow up using weighted polytomous regression. Follow-up hypertension odds also were compared in three pregnancy BP groups: normotensives (referent) and moderately elevated BP with or without PE-related placental/extraplacental membrane findings.

MAIN OUTCOME MEASURES

Stage 2 hypertension (SBP ≥140 mmHg and/or DBP ≥90 mmHg, or using antihypertensive medications) at follow up.

RESULTS

After excluding women with pregnancy hypertension (i.e. chronic, PE, gestational), mural hyperplasia and unaltered/abnormal decidual vessels were each associated with Stage 2 hypertension at follow up: adjusted odds ratio (aOR) = 2.7, 95% CI 1.1-6.6, and aOR = 1.7 (95% CI 0.8-3.4), respectively. Women with moderately elevated BP in pregnancy and evidence of mural hyperplasia or unaltered/abnormal decidual vessels had greater odds of Stage 2 hypertension at follow up: aOR = 4.5 (95% CI 1.6-12.5 and aOR = 2.6, 95% CI 1.1-5.9, respectively.

CONCLUSIONS

PE-related placental/extraplacental membrane findings help risk-stratify women with moderately elevated BP in pregnancy for later development of hypertension.

TWEETABLE ABSTRACT

Placental findings associated with mother's risk of later-life hypertension.

Multi-Fetal Pregnancy, Preeclampsia, and Long-Term Cardiovascular Disease

Supplemental Digital Content is available in the text.

This Swedish register-based cohort study determined the separate and joint contribution of preeclampsia and multi-fetal pregnancy on a woman’s risk of cardiovascular disease (CVD) later in life. The study included 892 425 first deliveries between 1973 and 2010 of women born 1950 until 1971, identified in the Swedish Medical Birth Register. A composite outcome of CVD was retrieved through linkage with the National Patient and Cause of Death Registers. Cox proportional hazard regression was used to assess the risk of CVD in women who had preeclampsia in a singleton or multi-fetal pregnancy, adjusting for potential confounders, and presented as adjusted hazard ratios. Compared with women who had a singleton pregnancy without preeclampsia (the referent group), women with preeclampsia in a singleton pregnancy had an increased risk of CVD (adjusted hazard ratio 1.75 [95% CI, 1.64–1.86]). Women who had a multi-fetal pregnancy without or with preeclampsia did not have an increased risk of future CVD (adjusted hazard ratios 0.94 [95% CI, 0.79–1.10] and 1.25 [95% CI, 0.83–1.86], respectively). As opposed to preeclampsia in a first singleton pregnancy, preeclampsia in a first multi-fetal pregnancy was not associated with increased risk of future CVD. This may support the theory that preeclampsia in multi-fetal pregnancies more often occurs as a result of the larger pregnancy-related burden on the maternal cardiovascular system and excessive placenta-shed inflammatory factors, rather than the woman’s underlying cardiovascular phenotype.

Association between phthalate exposure and blood pressure during pregnancy

BACKGROUND

Phthalates are endocrine disrupting chemicals (EDCs) that pose a serious hazard to the human health. Many epidemiological studies revealed a relationship between phthalates exposure and blood pressure in general population, while the relationship in pregnant women remains unknown.

OBJECTIVES

Aimed to elucidate whether phthalate exposure is associated with blood pressure among pregnant women.

METHODS

This study included 636 participants from Wuhan, China. Urine samples were conducted repeatedly in three trimesters, and 9 phthalates were measured in these samples. After each urine was sampled, all the participants completed blood pressure measurements. Associations between repeated measurements of phthalate concentration and blood pressure were evaluated by using generalized estimating equations. Stratified analysis by fetus gender was conducted.

RESULTS

Among the pregnant women with male fetuses, mono-i-butyl phthalate (MiBP) exposed in the 1st trimester was associated with the increased diastolic blood pressure (DBP) measured in the 2nd trimester, while the environmental risk score (ERS) measured in the 1st and 2nd trimester was positively associated with systolic blood pressure (SBP) and DBP in the 2nd trimester. No significant relationships were observed among all the population or pregnant women with female fetuses.

CONCLUSIONS

Exposure to higher levels of MiBP may be related to increased blood pressure during pregnancy in pregnant women with male fetuses.

Cardiovascular Disease-Related Pregnancy Complications Are Associated with Increased Maternal Levels and Trajectories of Cardiovascular Disease Biomarkers During and After Pregnancy

Background: Having a pregnancy complicated by hypertensive disorders of pregnancy (HDP) and/or having a small or preterm baby put a woman at risk for later cardiovascular disease (CVD). It is uncertain if higher maternal CVD risk factors (reflected by increased peripartum CVD biomarker levels) account for this risk, or if experiencing a complicated pregnancy itself increases a woman's CVD risk (reflected by an increase in biomarker trajectories from early pregnancy to postpartum). Methods: We conducted a secondary analysis of an 8-week mindful eating and stress reduction intervention in 110 pregnant women. We used mixed linear regression analysis to compare CVD biomarker levels and trajectories, between women with and without a CVD-related pregnancy complication (including HDP [gestational hypertension or preeclampsia] or having a small for gestational age [<10th percentile] or preterm [<37 weeks] baby), at three times: (1) 12-20 weeks of gestation, (2) 3 months postpartum, and (3) 9 months postpartum. CVD biomarkers studied included serum glucose, insulin, homeostasis model assessment of insulin resistance (HOMA-IR), body mass index (BMI), blood pressure (BP), interleukin-6 (IL-6), tumor necrosis factor, and lipids. We adjusted for age, maternal smoking, prepregnancy BMI, BP, age × time, and BMI × time. Results: Women had a mean age of 28 years (standard deviation [SD] 6), mean prior pregnancies of 0.8 (SD 1.0), and 22 women had one or more CVD-related pregnancy complications. HOMA-IR, diastolic BP, triglyceride, high-density lipoprotein cholesterol, and IL-6 average levels, but not trajectories, differed among women with complicated versus normal pregnancy (all p values were ≤0.04). Peripartum glucose and systolic BP trajectories were statistically greater in complicated versus normal pregnancies (p values were 0.008 and 0.01, respectively). Conclusion: We conclude that the experience of a complicated pregnancy in addition to elevated CVD risk factor levels may both increase a woman's risk of future CVD. ClinicalTrials.gov Identifier: NCT01307683.

Pregnancy-related events associated with subclinical cardiovascular disease burden in late midlife: SWAN

BACKGROUND AND AIMS

Reproductive factors are associated with later life CVD in women (e.g., age at first birth, preeclampsia, gestational diabetes), but studies have focused largely on premenopausal women. We examined the relationship of reproductive factors with subclinical CVD burden in late midlife women.

METHODS

We included 964 parous women from the Study of Women's Health Across the Nation (SWAN), who completed a reproductive history questionnaire at the 13th SWAN visit (2011-2012), and a carotid ultrasound and brachial-ankle pulse wave velocity (baPWV) assessment. The primary outcomes were carotid intima-media thickness, plaque, and baPWV; our secondary outcome was a composite subclinical CVD index created using these measures. Linear and logistic regression was performed to examine associations with individual subclinical CVD measures, and multinomial logistic regression was used in analyses of the composite index. Models adjusted for socio-demographics and cardiovascular risk factors.

RESULTS

Mean age at subclinical CVD assessment was 60.2 years (SD ± 2.7). History of gestational hypertension/preeclampsia was associated with greater carotid IMT (β: 0.038, p = 0.004). Earlier age at first birth was associated with subclinical CVD, but not when accounting for CVD risk factors. History of gestational diabetes was associated with greater baPWV, but not related to our composite index.

CONCLUSIONS

Pregnancy history is an important marker of subclinical CVD in late midlife and may impact the vasculature through distinct pathways. Future studies are necessary to evaluate racial/ethnic differences in the observed associations and to assess the benefit of a composite subclinical CVD index for earlier CVD risk modification in midlife women.

Early or late pregnancy loss and development of clinical cardiovascular disease risk factors: a prospective cohort study

OBJECTIVE

To assess the association between the outcome of a woman's first pregnancy and risk of clinical cardiovascular disease risk factors.

DESIGN

Prospective cohort study.

SETTING AND POPULATION

Nurses' Health Study II.

METHODS

Multivariable-adjusted Cox proportional hazards models were used to compute hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations between first pregnancy outcome and hypertension, type 2 diabetes, and hypercholesterolemia.

MAIN OUTCOME MEASURES

Hypertension, type 2 diabetes, and hypercholesterolemia.

RESULTS

Compared to women who reported a singleton live first birth, women with early spontaneous abortion (<12 weeks) had a greater rate of type 2 diabetes (HR: 1.20; 95% CI: 1.07-1.34) and hypercholesterolemia (HR: 1.06; 95% CI: 1.02-1.10), and a marginally increased rate of hypertension (HR: 1.05, 95% CI: 1.00-1.11). Late spontaneous abortion (12-19 weeks) was associated with an increased rate of type 2 diabetes (HR: 1.38; 95% CI: 1.14-1.65), hypercholesterolemia (HR: 1.11; 95% CI: 1.03-1.19), and hypertension (HR: 1.15; 95% CI: 1.05-1.25). The rates of type 2 diabetes (HR: 1.45; 95% CI: 1.13-1.87) and hypertension (HR: 1.15; 95% CI: 1.01-1.30) were higher in women who delivered stillbirth. In contrast, women whose first pregnancy ended in an induced abortion had lower rates of hypertension (HR: 0.87; 95% CI: 0.84-0.91) and type 2 diabetes (HR: 0.89; 95% CI: 0.79-0.99) than women with a singleton live birth.

CONCLUSIONS

Several types of pregnancy loss were associated with an increased rate of hypertension, type 2 diabetes, and hypercholesterolemia, which may provide novel insight into the pathways through which pregnancy outcomes and CVD are linked.

TWEETABLE ABSTRACT

Pregnancy loss is associated with later maternal risk of hypertension, type 2 diabetes, and hypercholesterolemia.

Hypertensive Disorders of Pregnancy and Maternal Cardiovascular Disease Risk Factor Development: An Observational Cohort Study

BACKGROUND

Women with a history of hypertensive disorders of pregnancy (HDP) are nearly twice as likely to develop cardiovascular disease (CVD) as those who are normotensive during pregnancy. However, the emergence of CVD risk factors after HDP is less well-understood.

OBJECTIVE

To identify associations between HDP and maternal CVD risk factors and chart the trajectory of risk factor development after pregnancy.

DESIGN

Observational cohort study.

SETTING

United States.

PARTICIPANTS

58 671 parous NHS II (Nurses' Health Study II) participants who did not have CVD or risk factors of interest at baseline.

MEASUREMENTS

Women were followed for self-reported physician diagnosis of chronic hypertension and hypercholesterolemia and confirmed type 2 diabetes mellitus (T2DM) from their first birth through 2013; mean follow-up ranged from 25 to 32 years across these end points. Multivariable Cox proportional hazards models estimated hazard ratios (HRs) and 95% CIs, with adjustment for prepregnancy confounders.

RESULTS

Compared with women who were normotensive during pregnancy, those with gestational hypertension (2.9%) or preeclampsia (6.3%) in their first pregnancy had increased rates of chronic hypertension (HRs, 2.8 [95% CI, 2.6 to 3.0] and 2.2 [CI, 2.1 to 2.3], respectively), T2DM (HRs, 1.7 [CI, 1.4 to 1.9] and 1.8 [CI, 1.6 to 1.9], respectively), and hypercholesterolemia (HRs, 1.4 [CI, 1.3 to 1.5] and 1.3 [CI, 1.3 to 1.4], respectively). Although these women were more likely to develop CVD risk factors throughout follow-up, the relative risk for chronic hypertension was strongest within 5 years after their first birth. Recurrence of HDP further elevated risks for all end points.

LIMITATION

Participants self-reported HDP.

CONCLUSION

Women with HDP in their first pregnancy had increased rates of chronic hypertension, T2DM, and hypercholesterolemia that persisted for several decades. These women may benefit from lifestyle intervention and early screening to reduce lifetime risk for CVD.

PRIMARY FUNDING SOURCE

National Institutes of Health.

Life Course Trajectories of Cardiovascular Risk Factors in Women With and Without Hypertensive Disorders in First Pregnancy: The HUNT Study in Norway

Background Women with hypertensive pregnancy disorders have adverse levels of cardiovascular risk factors. It is unclear how this adverse risk factor profile evolves during adult life. We compared life course trajectories of cardiovascular risk factors in women with preeclampsia or gestational hypertension in their first pregnancy to normotensive women. Methods and Results We linked information on cardiovascular risk factors from the population-based HUNT (Nord-Trøndelag Health Study) surveys with pregnancy information from the Medical Birth Registry of Norway. Trajectories of cardiovascular risk factors were constructed for 22 308 women with a normotensive first pregnancy; 1092 with preeclampsia, and 478 with gestational hypertension in first pregnancy. Already before first pregnancy, women with preeclampsia in their first pregnancy had higher measures of adiposity, blood pressure, heart rate, and serum lipids and glucose compared with women with a normotensive first pregnancy. After first pregnancy, there was a parallel development in cardiovascular risk factor levels, but women with a normotensive first pregnancy had a time lag of >10 years compared with the preeclampsia group. There were no clear differences in risk factor trajectories between women with gestational hypertension and women with preeclampsia. Conclusions Women with hypertensive pregnancy disorders in their first pregnancy had an adverse cardiovascular risk factor profile before pregnancy compared with normotensive women, and the differences persisted beyond 50 years of age. Hypertensive disorders in pregnancy signal long-term increases in modifiable cardiovascular risk factors, and may be used to identify women who would benefit from early prevention strategies.

Role of endogenous digitalis-like factors in the clinical manifestations of severe preeclampsia: a sytematic review

Endogenous digitalis-like factor(s), originally proposed as a vasoconstrictor natriuretic hormone, was discovered in fetal and neonatal blood accidentally because it cross-reacts with antidigoxin antibodies (ADAs). Early studies using immunoassays with ADA identified the digoxin-like immuno-reactive factor(s) (EDLF) in maternal blood as well, and suggested it originated in the feto-placental unit. Mammalian digoxin-like factors have recently been identified as at least two classes of steroid compounds, plant derived ouabain (O), and several toad derived bufodienolides, most prominent being marinobufagenin (MBG). A synthetic pathway for MBG has been identified in mammalian placental tissue. Elevated maternal and fetal EDLF, O and MBG have been demonstrated in preeclampsia (PE), and inhibition of red cell membrane sodium, potassium ATPase (Na, K ATPase (NKA)) by EDLF is reversed by ADA fragments (ADA-FAB). Accordingly, maternal administration of a commercial ADA-antibody fragment (FAB) was tested in several anecdotal cases of PE, and two, small randomized, prospective, double-blind clinical trials. In the first randomized trial, ADA-FAB was administered post-partum, in the second antepartum. In the post-partum trial, ADA-FAB reduced use of antihypertensive drugs. In the second trial, there was no effect of ADA-FAB on blood pressure, but the fall in maternal creatinine clearance (CrCl) was prevented. In a secondary analysis using the pre-treatment maternal level of circulating Na, K ATPase (NKA) inhibitory activity (NKAI), ADA-FAB reduced the incidence of pulmonary edema and, unexpectedly, that of severe neonatal intraventricular hemorrhage (IVH). The fall in CrCl in patients given placebo was proportional to the circulating level of NKAI. The implications of these findings on the pathophysiology of the clinical manifestations PE are discussed, and a new model of the respective roles of placenta derived anti-angiogenic (AAG) factors (AAGFs) and EDLF is proposed.

Pregnancy-Related Risk Factors Are Associated With a Significant Burden of Treated Hypertension Within 10 Years of Delivery: Findings From a Population-Based Norwegian Cohort

BACKGROUND

The association between pregnancy complications and women's later cardiovascular disease has, primarily, been evaluated in studies lacking information on important covariates. This report evaluates the prospective associations between pregnancy-related risk factors (preeclampsia/eclampsia, gestational hypertension, pregestational and gestational diabetes mellitus, preterm delivery, and fetal growth restriction) and pharmacologically treated hypertension within 10 years after pregnancy, while adjusting for a wide range of covariates.

METHODS AND RESULTS

Prepregnancy normotensive women participating in the MoBa (Norwegian Mother and Child Cohort Study) from January 2004 through July 2009 were linked to the Norwegian Prescription Database to identify women with pharmacologically treated hypertension beyond the postpartum period of 3 months. The burden of hypertension associated with pregnancy-related risk factors was evaluated using an attributable fraction method. A total of 1480 women developed pharmacologically treated hypertension within the follow-up among 60 027 women (rate of hypertension, 3.6/1000 person-years). The proportion of hypertension associated with a history of preeclampsia/eclampsia, gestational hypertension, preterm delivery, and pregestational or gestational diabetes mellitus was 28.6% (95% confidence interval, 25.5%-31.6%) on the basis of multivariable analyses adjusting for numerous covariates. The proportion was similar for women with a healthy prepregnancy body mass index (18.5-24.9 kg/m2; attributable fraction (AF)% 25.9%; 95% confidence interval, 21.3%-30.3%), but considerably higher for nulliparous women at baseline within the first 5 years of follow-up. Small-for-gestational age, however, did not increase subsequent hypertension risk in multivariable analyses.

CONCLUSIONS

A structured postpartum follow-up of high-risk women identified through pregnancy-related risk factors would facilitate personalized preventive strategies to postpone or avoid onset of premature cardiovascular events.

Cardiovascular risk profile at the age of 40-45 in women with previous hyperemesis gravidarum or hypertensive disorders in pregnancy: A population-based study

OBJECTIVE

To assess midlife cardiovascular risk profiles in women with a history of hyperemesis or hypertensive disorders in pregnancy compared to women with none of the studied pregnancy complications.

STUDY DESIGN

Population-based study. Cardiovascular risk factors at the age of 40-45 among women with previous singleton births only were studied through linkage of the Norwegian Birth Registry and a Norwegian screening program (the Age 40 Program).

MAIN OUTCOME MEASURES

Family history of coronary heart disease, body mass index, smoking, physical activity, systolic and diastolic blood pressure, heart rate, cholesterol, triglycerides, antihypertensive treatment and diabetes.

RESULTS

Among 178,231 women participating in the Age 40 Program with previous singleton births; 2140 (1.2%) had experienced hyperemesis and 13,348 (7.5%) hypertensive disorders in pregnancy. Women who had suffered from hyperemesis were less physically active. The differences in mean systolic blood pressure and body mass index were probably clinically irrelevant. In women with a history of hypertensive disorders in pregnancy, systolic and diastolic blood pressure and body mass index were higher, and they were more likely to report diabetes in midlife. Women who had suffered from hyperemesis or hypertensive disorders in pregnancy were less likely to be daily smokers.

CONCLUSION

Women with hypertensive disorders in pregnancy seemed to have an unfavorable cardiovascular risk profile in midlife compared to women with uncomplicated pregnancies. In contrast there was no consistent evidence of increased risk subsequent to hyperemesis gravidarum. The proportion of daily smokers was lower in women with either of the two pregnancy complications.

History of Adverse Pregnancy Outcomes, Blood Pressure, and Subclinical Vascular Measures in Late Midlife: SWAN (Study of Women's Health Across the Nation)

BACKGROUND

Adverse pregnancy outcomes, such as preterm birth (PTB), have been associated with elevated risk of maternal cardiovascular disease, but their effect on late midlife blood pressure (BP) and subclinical vascular measures remains understudied.

METHODS AND RESULTS

We conducted a cross-sectional analysis with 1220 multiethnic parous women enrolled in SWAN (Study of Women's Health Across the Nation) to evaluate the impact of self-reported history of adverse pregnancy outcomes (PTB, small-for-gestational-age, stillbirth), on maternal BP, mean arterial pressure, and subclinical vascular measures (carotid intima-media thickness, plaque, and pulse wave velocity) in late midlife. We also examined whether these associations were modified by race/ethnicity. Associations were tested in linear and logistic regression models adjusting for sociodemographics, reproductive factors, cardiovascular risk factors, and medications. Women were on average aged 60 years and 255 women reported a history of an adverse pregnancy outcome. In fully adjusted models, history of PTB was associated with higher BP (systolic: β=6.40; SE, 1.62 [P<0.0001] and diastolic: β=3.18; SE, 0.98 [P=0.001]) and mean arterial pressure (β=4.55; SE 1.13 [P<0.0001]). PTB was associated with lower intima-media thickness, but not after excluding women with prevalent hypertension. There were no significant associations with other subclinical vascular measures.

CONCLUSIONS

Findings suggest that history of PTB is associated with higher BP and mean arterial pressure in late midlife. Adverse pregnancy outcomes were not significantly related to subclinical cardiovascular disease when excluding women with prevalent hypertension. Future studies across the menopause transition may be important to assess the impact of adverse pregnancy outcomes on midlife progression of BP.

The relationships between timing of first childbirth, parity, and health-related quality of life

PURPOSE

A few studies have investigated the relationship between age at first childbirth and health-related quality of life (HRQoL). This study examined the relationship between age at first childbirth and HRQoL and whether parity mediates this timing of the first childbirth-HRQoL relationship in women aged 50 years or above.

METHODS

The study population included 5146 parous women ≥ 50 years in the cross-sectional survey, the Korea National Health and Nutrition Examination Survey 2010-2012. HRQoL was evaluated by the EuroQol five-dimensional descriptive system. Participants were grouped according to quartiles of age at first childbirth (ranges: 13-21, 22-23, 24-25, and 26-44 years). This study used linear regression analysis to examine the relationship between age at first childbirth and HRQoL and on each dimension. Mediation analysis was used to examine the contribution of age at first childbirth to HRQoL and to each dimension.

RESULTS

This study found the increasing pattern of HRQoL across quartiles of age at first childbirth (P for trend = 0.030). Odds of problems in self-care and anxiety/depression dimensions significantly increased across the quartiles. Women with later age at first childbirth tended to have better HRQoL (B = 0.352, P = 0.003); parity significantly contributed to this relationship. Decreasing parity accounted for 33.5% of the relationship between late first childbirth and increased HRQoL. Early age at first childbirth significantly increased odds of the mobility problem through increasing parity.

CONCLUSIONS

Women of an early age at first childbirth tended to have lower HRQoL through giving more deliveries. Our findings suggest that more attention needs to be given to women with early pregnancy and more delivery to prevent impaired HRQoL.

Invited Commentary: Gestational Hypertension and Diabetes-A Major Public Health Concern

The obesity epidemic in the United States and other countries has contributed to an increase in the rates of gestational diabetes and hypertension. In the past, it was thought that most cases of gestational diabetes and hypertension would resolve after completion of pregnancy. In this issue of the Journal, Pace et al. (Am J Epidemiol. 2017;186(10):1115-1124) clearly documented that both gestational diabetes and hypertension lead to diabetes and hypertension and that the combination of both during pregnancy leads to very high rates of subsequent diabetes and hypertension. A new generation of epidemiology studies using the evolving new technologies and genetics (host susceptibility studies) are needed to improve our understanding of the etiology of gestational diabetes and hypertension. Early identification of women at risk of gestational diabetes and hypertension, better treatment during pregnancy, and preventive and clinical therapies for treatment of diabetes and hypertension after pregnancy are very important for improving women's health and reducing risk of cardiovascular disease later in life.

Hypertensive disorders of pregnancy: a strong risk factor for subsequent hypertension 5 years after delivery

Hypertensive disorders of pregnancy are known to be a risk factor for future cardiovascular diseases. In contrast, there is a paucity of data on the not so distant future prognosis of hypertensive disorders of pregnancy. In the present study, we evaluated the incidence of the diseases causing cardiovascular problems (hypertension, diabetes mellitus, dyslipidemia and metabolic syndrome) 5 years after delivery in Japanese women with hypertensive disorders of pregnancy. We performed a double-cohort study and compared medical conditions between women with and without a history of hypertensive disorders of pregnancy. A total of 1513 women who participated in the cohort study were invited to undergo a medical checkup 5 years after the index delivery, of whom 829 responded. After excluding pregnant and lactating women at the time of examination, 25 women with hypertensive disorders of pregnancy and 746 control subjects were analyzed. The incidence of hypertension was significantly higher among women with hypertensive disorders of pregnancy than women who were normotensive during pregnancy (24.0 vs. 2.5%, P<0.001). They were also at an increased risk of subsequent hypertension 5 years after the index delivery, after adjusting for confounding factors such as age, body mass index, family history of hypertension and salt intake (odds ratio 7.1, 95% CI, 2.0-25.6, P<0.003). These is no significant difference in the incidence of diabetes mellitus, dyslipidemia and metabolic syndrome. In conclusion, hypertensive disorders of pregnancy are strong risk factors for subsequent hypertension only 5 years after delivery.

Maternal Serum B-Cell Activating Factor Levels

Hypertensive disorders of pregnancy are a leading cause of maternal and perinatal morbidity and mortality. Early suppression of B-cell lymphopoiesis is necessary for a normal pregnancy. Dysregulation of factors critical to B-cell survival may result in pregnancy complications, including hypertension. In this prospective observational study at a single medical center, serum levels of BAFF (B-cell activating factor) were measured in pregnant participants at each trimester, at delivery, and postpartum and in nonpregnant controls at a single time point. Comparisons were made between nonpregnant and pregnant subjects and between time periods of pregnancy. First-trimester serum BAFF levels were further tested for association with hypertensive disorders of pregnancy. The study included 149 healthy pregnant women, 25 pregnant women with chronic hypertension, and 48 nonpregnant controls. Median first-trimester serum BAFF level (ng/mL) for healthy women (0.90) was lower than median serum BAFF levels for women with chronic hypertension (0.96; P =0.013) and controls (1.00; P =0.002). Serum BAFF levels steadily declined throughout pregnancy, with the median second-trimester level lower than the corresponding first-trimester level (0.77; P =0.003) and the median third-trimester level lower than the corresponding second-trimester level (0.72; P =0.025). The median first-trimester serum BAFF level was elevated in women who subsequently developed hypertension compared with women who remained normotensive (1.02 versus 0.85; P =0.012), with the area under the receiver operating characteristic curve being 0.709. First-trimester serum BAFF level may be an early and clinically useful predictor of hypertensive disorders of pregnancy.

Association between pregravid physical activity and family history of stroke and risk of stillbirth: population-based cohort study

OBJECTIVES

To evaluate whether family history of disease and pregravid lifestyle and cardiovascular risk factors are associated with subsequent stillbirth delivery.

DESIGN

Prepregnancy cohort study.

SETTING

Cohort Norway regional health surveys (1994-2003) linked to Medical Birth Registry of Norway for deliveries through 2012.

PARTICIPANTS

13 497 singleton births (> 22 weeks gestation) in 8478 women.

MAIN OUTCOME MEASURE

Risk of stillbirth evaluated by Poisson regression.

RESULTS

Mean (SD) length of follow-up was 5.5 (3.5) years. In analyses adjusting for baseline age and length of follow-up, ≥3 hours of baseline past-year vigorous physical activity per week (resulting in shortness of breath/sweating) was associated with increased risk of stillbirth compared with <1 hour/week of vigorous activity (incidence rate ratio, IRR 2.46; 95% CI 1.23 to 4.90). In contrast, baseline past-year light physical activity of ≥3 hours per week associated with reduced risk of stillbirth compared with <3 hours of light physical activity per week (IRR 0.53; 95% CI 0.30 to 0.93). A family history of stroke associated with increased risk of stillbirth delivery (IRR 2.53; 95% CI 1.06 to 6.01). Because overweight/obese women may experience shortness of breath and sweating with less physical exertion than normal weight women, a sensitivity analysis was conducted limited to women with a normal BMI (> 18.5 and <25 kg/m²). Vigorous activity of ≥3 hours per week (IRR of 4.50; 95% CI 1.72 to 11.79) and a family history of stroke (IRR of 3.81; 95% CI 1.31 to 11.07) were more strongly related to stillbirth risk among women with a normal BMI than that observed for all women combined. Established risk factors also associated with stillbirth risk.

CONCLUSIONS

The study identified physical activity and family history of stroke as potential new risk factors for stillbirth delivery.

Age at first birth and risk of later-life cardiovascular disease: a systematic review of the literature, its limitation, and recommendations for future research

Background

Cardiovascular disease (CVD) is the principal contributor to the burden of disease and mortality worldwide. Previous studies observed associations between early age at first birth (AFB) and all-cause mortality. AFB may be associated with CVD both through physiological and sociobiological pathways. In this paper, we review the literature on AFB and CVD events and mortality. Additionally, we provide an overview of limitations of the current research and recommendations for future research.

Methods

PubMed and Web of Science databases were searched for observational studies published between 1980-June 2016, investigating associations between AFB and CVD events and mortality. Data were extracted using a pre-defined list.

Results

A total of 20 publications, reporting on 33 associations, were included in the review. Ten studies observed a positive association between early AFB and CVD while two studies observed a positive association between later AFB and CVD. Substantial methodological limitations were observed related to: operationalization of exposure categories, choice of reference category, sample size, follow-up time and possibly over adjustment.

Conclusions

Early AFB is possibly related to CVD. More work, in particular from large cohort studies starting before reproductive age is reached, is needed to better investigate this relationship, and to ascertain causal pathways that may explain observed associations.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-017-4519-x) contains supplementary material, which is available to authorized users.

Age at First Childbirth and Hypertension in Postmenopausal Women

Whether age at first childbirth has an effect on hypertension incidence is unclear. The objectives of this study were to examine the relationship between age at first childbirth and hypertension and to examine whether degree of obesity, measured as body mass index, mediates age at first childbirth-related hypertension in postmenopausal women. This study analyzed 4779 postmenopausal women data from the Korea National Health and Nutrition Examination Survey 2010 to 2012. Logistic regression analyses were used to investigate relationship between age at first childbirth and hypertension. Mediation analysis was performed to examine the contribution of body mass index to age at first childbirth-related hypertension. Mean of participants’ age at first childbirth and current age were 23.8 and 63.4 years, respectively. The prevalence of hypertension was 51.1%. Age at first childbirth was significantly associated with the prevalence of hypertension (odds ratio, 0.963; 95% confidence interval, 0.930–0.998; P =0.036). Women with age at first childbirth ≤19 years had significantly higher risk of hypertension (odds ratio, 1.61; 95% confidence interval, 1.17–2.23; P =0.004) compared with those >19 years. Multivariable-adjusted prevalence of hypertension was significantly lower in women who delivered the first infant at 20 to 24 (45.5%), 25 to 29 (46.1%), and ≥30 (39.9%) years compared with those at ≤19 years (58.4%). Body mass index completely mediated age at first childbirth–hypertension relationship (indirect effect: odds ratio, 0.992; 95% confidence interval, 0.987–0.998; P =0.008). Age at first childbirth was significantly associated with hypertension in postmenopausal women. Body mass index mediated the effects of age at first childbirth on hypertension.