Childbearing, Child-Rearing, Cardiovascular Risk Factors, and Progression of Carotid Intima-Media Thickness

Child rearing or childbearing? Risk of cardiovascular diseases associated to parity and number of children

BACKGROUND

An increased risk of cardiovascular diseases (CVD) has been associated with women's parity, but whether or not this association reflects a direct pregnancy effect, or exposure to factors related to childrearing, still appears unclear. We assessed the CVD risk associated with number of children separately by gender and tested effect modification by socioeconomic position (SEP) and employment status, in order to elucidate the possible mechanisms underlying this association.

METHODS

The study population was composed of 20,904 men and 25,246 women who were interviewed in one of two National Health Surveys conducted in 2000 and 2005 in Italy. These subjects were followed for CVD incidence up to 2014 through record-linkage with national archives of mortality and hospitalisations. CVD risk was estimated by Cox regression models that were adjusted for socio-demographics, perceived health, lifestyles, biological CVD risk factors and for other potential confounders.

RESULTS

CVD incidence was significantly increased among men with 3 or more children (HR = 1.26, 95% CI: 1.02-1.56) and among women with 2 and with 3 or more children (HR = 1.42, 95% CI: 1.10-1.83; and HR = 1.39, 95% CI: 1.03-1.87, respectively) compared to subjects without children and no significant gender differences were observed. Subjects with lower SEP displayed stronger associations with parity and a higher number of children for both genders; by contrast, no modifying effect of employment status was observed.

CONCLUSIONS

Taken together, the significant association between higher parity and CVD risk in both genders, and the higher risk of CVD associated with higher parity among lower SEP parents, suggests that childrearing has a potential effect on the development of CVD that is more pronounced among disadvantaged families, although a concurrent effect of childbearing cannot be completely excluded.

Female Reproductive Events and Subclinical Atherosclerosis of the Brain and Carotid Arteriopathy: the Ohasama Study

AIMS

Few studies have investigated the subclinical atherosclerotic changes in the brain and carotid artery, and in East Asian populations. We sought to investigate whether gravidity, delivery, the age at menarche and menopause and estrogen exposure period are associated with subclinical atherosclerosis of the brain and carotid arteriopathy.

METHODS

This cross-sectional study formed part of a cohort study of Ohasama residents initiated in 1986. Brain atherosclerosis and carotid arteriopathy were diagnosed as white matter hyperintensity (WMH) and lacunae evident on brain magnetic resonance imaging (MRI) and carotid intimal media thickness (IMT) or plaque revealed by ultrasound, respectively. The effect of the reproductive events on brain atherosclerosis and carotid arteriopathy was investigated using logistic regression and general linear regression models after adjusting for covariates.

RESULTS

Among 966 women aged ≥ 55 years in 1998, we identified 622 and 711 women (mean age: 69.2 and 69.7 years, respectively) who underwent either MRI or carotid ultrasound between 1992-2008 or 1993-2018, respectively. The highest quartile of gravidity (≥ 5 vs. 3) and delivery (≥ 4 vs. 2), and the highest and second highest (3 vs. 2) quartiles of delivery were associated with an increased risk of WMH and carotid artery plaque, respectively. Neither of age at menarche, menopause, and estrogen exposure period estimated by subtracting age at menarche from age at menopause was associated with atherosclerotic changes of brain and carotid arteries.

CONCLUSIONS

Higher gravidity and delivery are associated with subclinical atherosclerosis of the brain and carotid plaque.

Cerebrovascular disease in pregnancy and puerperium: perspectives from neuroradiologists

Pregnancy-related cerebrovascular disease is a serious complication of pregnancy and puerperium. The etiology and pathological mechanisms of cerebrovascular disease are complex, involving changes in the cardiovascular, endocrine, and immune systems. Vascular risk factors during pregnancy and puerperium may cause vasospasm and endothelial cell damage leading to cerebral ischemia, hemorrhage, posterior reversible encephalopathy syndrome (PRES), and reversible cerebral vasoconstriction syndrome. Arterial or venous obstruction may damage the blood-brain barrier (BBB) and impede venous return, resulting in cerebral edema, hemorrhage, and intracranial hypertension. Pregnancy with hypercoagulability may threaten the lives of both the mother and the developing fetus. With improvements in stroke treatment during pregnancy and puerperium, neuroradiologists have gained new insights into this problem. This article reviews the pathogenesis, imaging findings, and risk factors of stroke during pregnancy and puerperium, focusing on imaging diagnosis and prognostic assessment.

Arterial Structure and Stiffness Are Altered in Young Adults Born Preterm

OBJECTIVE

Preterm birth has been associated with changes in arterial structure and function. Association with complications occurring during the neonatal period, including bronchopulmonary dysplasia, on vascular outcomes in adulthood is unknown. Approach and Results: We evaluated a cohort of 86 adults born preterm (below 30 weeks of gestation), compared to 85 adults born term, at a mean age of 23 years. We performed ultrasonographic assessment of the dimensions of the ascending aorta, carotid and brachial arteries, and estimated flow-mediated dilation, carotid-femoral pulse wave velocity, augmentation index corrected for heart rate, and carotid intima-media thickness. All analyses were performed with and without adjustment for potential confounding variables, including height, sex, and body mass index. Ascending aorta diameter in diastole was smaller in the preterm group, but carotid and brachial arteries were similar. Carotid and brachial strain, a marker of arterial distensibility, was smaller in the preterm group, while carotid-femoral pulse wave velocity, was similar between groups, indicating similar aortic stiffness. Carotid intima-media thickness, endothelial function flow-mediated dilation, blood nitrite, and nitrate levels were similar between groups. Individuals with bronchopulmonary dysplasia had lower brachial artery strain suggesting long-term association of this neonatal complication with vascular structure. Diastolic blood pressure was higher in the preterm group and was associated with decreased brachial and carotid distensibility.

CONCLUSIONS

Young adults born preterm display alterations in arterial distensibility that are associated with a history of bronchopulmonary dysplasia.

Cooking fuels use and carotid intima-media thickness during early pregnancy of women in Myanmar

BACKGROUND

Fuels burned in households for cooking cause indoor air pollution, exposing those who are cooking. Despite the mounting evidence of the effects of fuels use on health, few studies focus on the effect of cooking fuels have on carotid intima-media thickness (CIMT), a surrogate atherosclerosis biomarker in the early stages of pregnancy. This study aimed to examine the association between the use of cooking fuels and CIMT during early trimester of pregnancy among cooking women in Myanmar.

METHODOLOGY

In this cross-sectional study, a part of an ongoing birth cohort analysis, a total of 192 cooking pregnant women over 18 years with gestational weeks less than 18 were recruited from 15 rural health centers in Nay Pyi Taw from September to November 2019. Sociodemographic data, residential data, and fuels use data were collected with semi-structured questionnaires in face-to-face interviews. Anthropometric, hemodynamic, blood lipids, and ultrasound CIMT measurements were performed under standard protocols. Multiple linear regression was modeled to explore associations.

RESULTS

The study included 70 firewood fuel users, 26 charcoal fuel users, and 96 electricity fuel users. Following adjustments for potential confounding factors, firewood use was significantly associated with the increase of all CIMT analyzed. Importantly, a greater increase of mean CIMT of the right common carotid artery (RCCA; β = 0.033 mm; 95%CI: 0.006, 0.058; P<0.05) had significant association with charcoal use compared to firewood use (β = 0.029 mm; 95%CI: 0.010, 0.049; P<0.05).

CONCLUSIONS

Our findings demonstrate that the indoor use of cooking fuels that cause indoor air pollution, such as firewood and charcoal, is a considerable risk factor for human health and is associated with increased CIMT, wherein charcoal use contributes to more increase of mean CIMT of the RCCA. Measures to prevent health risks related to the use of such fuels should be instituted early on during pregnancy.

Infertility, Gravidity, and Risk Of Diabetes among High-Risk Women in the Diabetes Prevention Program Outcomes Study

OBJECTIVE

The extent to which infertility and pregnancy independently increase risk of diabetes and subclinical atherosclerosis is not known.

RESEARCH DESIGN AND METHODS

We conducted a secondary analysis of Diabetes Prevention Program (DPP) and the DPP Outcomes Study over a 15-year period. We included women who answered questions about gravidity and infertility at baseline (n = 2085). Infertility was defined as > 1 year of unsuccessful attempts to conceive; thus, women could have histories of infertility as well as pregnancy. Risk of diabetes associated with gravidity and infertility was calculated using Cox proportional hazards models adjusting for age, race/ethnicity, treatment arm, body mass index, and pregnancy during the study. Among women who underwent assessment of coronary artery calcification (CAC) (n = 1337), odds of CAC were calculated using logistic regression models with similar covariates.

RESULTS

Among premenopausal women (n = 1075), women with histories of pregnancy and infertility (n = 147; hazard ratio [HR] 1.80; 95% confidence interval [CI] 1.30, 2.49) and women with histories of pregnancy without infertility (n = 736; HR 1.49; 95% CI 1.15, 1.93) had greater diabetes risk than nulligravid women without infertility (n = 173). Premenopausal nulligravid women with histories of infertility had a non-significant elevation in risk, although the number of these women was small (n = 19; HR 1.63; 95% CI 0.88, 3.03). Associations were not observed among postmenopausal women (n = 1010). No associations were observed between infertility or pregnancy with CAC.

CONCLUSIONS

Pregnancy, particularly combined with a history of infertility, confers increased risk of diabetes but not CAC among glucose-intolerant premenopausal women.

A Systematic Review of Vascular Structure and Function in Pre-eclampsia: Non-invasive Assessment and Mechanistic Links

Hypertensive disorders of pregnancy, such as pre-eclampsia, are known to be independently associated with the development of premature cardiovascular disease (CVD) in women. In pre-eclampsia, the placenta secretes excess anti-angiogenic factors into the maternal circulation, leading to widespread endothelial damage, and inflammation. This endothelial damage is evidenced to persist beyond the acute illness. However, whether it is permanent and responsible for the elevated rates of premature CVD seen in this at-risk group remains unclear. A systematic review of the available literature with respect to vascular structure and function prior to, during and after a pregnancy complicated by pre-eclampsia was performed. Studies non-invasively assessing vascular structure using carotid intima-media thickness (CIMT), retinal microvasculature caliber, CT coronary angiogram, or coronary calcium scores were included. Vascular function was assessed using brachial flow-mediated dilation (FMD), pulse wave analysis (PWA), and peripheral arterial tonometry (PAT). In total 59 articles were included (13 CIMT, 5 CTCA/Ca score, five retinal microvasculature, 27 FMD, 7 PAT, and 14 PWV/PWA), consisting of prospective and retrospective cohort, and case-control studies. Change in vascular structure was evidenced with significant increases in CIMT by 73-180 μm greater than that of non-affected women. This is tempered by other studies reporting resolution of structural changes postpartum, highlighting the need for further research. Accelerated coronary calcification and plaque deposition was identified, with greater rates of increased calcium scores and subclinical coronary artery disease shown by CTCA in women with a history of pre-eclampsia at 30 years postpartum. Impaired endothelial function was consistently reported prior to, during and immediately after pregnancy as evidenced by differences in FMD of 1.7-12.2% less than non-affected women, an increase in PWV by 13.2-26%, and reduced retinal microvascular caliber and arterial elasticity indices. The evidence was less conclusive for the persistence of long-term endothelial dysfunction. Understanding the underlying mechanistic links between pre-eclampsia and CVD is a key step to identifying targeted therapies aimed at "repairing the endothelium" and attenuating risk. This review has highlighted the need for a greater understanding of vascular structure and function following pre-eclampsia through high quality studies with large sample sizes, particularly in the longer postpartum period when clinical CVD disease starts to manifest.

A Systematic Review of Vascular Structure and Function in Pre-eclampsia: Non-invasive Assessment and Mechanistic Links

Hypertensive disorders of pregnancy, such as pre-eclampsia, are known to be independently associated with the development of premature cardiovascular disease (CVD) in women. In pre-eclampsia, the placenta secretes excess anti-angiogenic factors into the maternal circulation, leading to widespread endothelial damage, and inflammation. This endothelial damage is evidenced to persist beyond the acute illness. However, whether it is permanent and responsible for the elevated rates of premature CVD seen in this at-risk group remains unclear. A systematic review of the available literature with respect to vascular structure and function prior to, during and after a pregnancy complicated by pre-eclampsia was performed. Studies non-invasively assessing vascular structure using carotid intima-media thickness (CIMT), retinal microvasculature caliber, CT coronary angiogram, or coronary calcium scores were included. Vascular function was assessed using brachial flow-mediated dilation (FMD), pulse wave analysis (PWA), and peripheral arterial tonometry (PAT). In total 59 articles were included (13 CIMT, 5 CTCA/Ca score, five retinal microvasculature, 27 FMD, 7 PAT, and 14 PWV/PWA), consisting of prospective and retrospective cohort, and case-control studies. Change in vascular structure was evidenced with significant increases in CIMT by 73–180 μm greater than that of non-affected women. This is tempered by other studies reporting resolution of structural changes postpartum, highlighting the need for further research. Accelerated coronary calcification and plaque deposition was identified, with greater rates of increased calcium scores and subclinical coronary artery disease shown by CTCA in women with a history of pre-eclampsia at 30 years postpartum. Impaired endothelial function was consistently reported prior to, during and immediately after pregnancy as evidenced by differences in FMD of 1.7–12.2% less than non-affected women, an increase in PWV by 13.2–26%, and reduced retinal microvascular caliber and arterial elasticity indices. The evidence was less conclusive for the persistence of long-term endothelial dysfunction. Understanding the underlying mechanistic links between pre-eclampsia and CVD is a key step to identifying targeted therapies aimed at “repairing the endothelium” and attenuating risk. This review has highlighted the need for a greater understanding of vascular structure and function following pre-eclampsia through high quality studies with large sample sizes, particularly in the longer postpartum period when clinical CVD disease starts to manifest.

Mechanisms of Sex Disparities in Cardiovascular Function and Remodeling

Epidemiological studies demonstrate disparities between men and women in cardiovascular disease prevalence, clinical symptoms, treatments, and outcomes. Enrollment of women in clinical trials is lower than men, and experimental studies investigating molecular mechanisms and efficacy of certain therapeutics in cardiovascular disease have been primarily conducted in male animals. These practices bias data interpretation and limit the implication of research findings in female clinical populations. This review will focus on the biological origins of sex differences in cardiovascular physiology, health, and disease, with an emphasis on the sex hormones, estrogen and testosterone. First, we will briefly discuss epidemiological evidence of sex disparities in cardiovascular disease prevalence and clinical manifestation. Second, we will describe studies suggesting sexual dimorphism in normal cardiovascular function from fetal life to older age. Third, we will summarize and critically discuss the current literature regarding the molecular mechanisms underlying the effects of estrogens and androgens on cardiac and vascular physiology and the contribution of these hormones to sex differences in cardiovascular disease. Fourth, we will present cardiovascular disease risk factors that are positively associated with the female sex, and thus, contributing to increased cardiovascular risk in women. We conclude that inclusion of both men and women in the investigation of the role of estrogens and androgens in cardiovascular physiology will advance our understanding of the mechanisms underlying sex differences in cardiovascular disease. In addition, investigating the role of sex-specific factors in the development of cardiovascular disease will reduce sex and gender disparities in the treatment and diagnosis of cardiovascular disease. © 2019 American Physiological Society. Compr Physiol 9:375-411, 2019.

Association between number of children and carotid intima-media thickness in Bangladesh

Previous studies on the association between number of children and carotid intima-media thickness (cIMT) were limited to Western populations. Pregnancy in women is associated with physiologic changes that may influence the risk of cardiovascular disease. Comparing the association between number of children and cIMT in men and women can provide insights on whether the association may be due to pregnancy. We investigated the association between number of children and cIMT among 718 female (mean age 37.5 years) and 417 male participants (mean age 41.3 years), randomly selected from the Health Effect of Arsenic Longitudinal Study (HEALS), a population-based cohort study in Bangladesh. Multivariate linear regression was used to assess the association and to control for education attainment, history of diabetes, age, smoking, betel use, BMI, systolic blood pressure, and diastolic blood pressure. The average number of children was 4.43 for women and 3.74 for men. There were no nulliparous women. We observed a positive association between number of children and cIMT in women. Mean cIMT increased by 4.5 μm (95% CI, 0.8–8.1) per increment of one birth (P = 0.02). Compared to women with two children, cIMT in women with 4 children and ≥5 children was 23.6μm (95%CI, 2.6–44.7; P = 0.03) and 25.1 μm (95%CI, 3.5–46.6; P = 0.02) greater, respectively. The association was not modified by BMI, SBP, betel use or age. Data in men showed no evidence of association (P = 0.4). The finding suggests a role of high parity in atherosclerosis in women of a low-income, high parity population.

Does pregnancy alter life-course lipid trajectories? Evidence from the HUNT Study in Norway

We examined the association between pregnancy and life-course lipid trajectories. Linked data from the Nord-Trøndelag Health Study and the Medical Birth Registry of Norway yielded 19,987 parous and 1,625 nulliparous women. Using mixed-effects spline models, we estimated differences in nonfasting lipid levels from before to after first birth in parous women and between parous and nulliparous women. HDL cholesterol (HDL-C) dropped by -4.2 mg/dl (95% CI: -5.0, -3.3) from before to after first birth in adjusted models, a 7% change, and the total cholesterol (TC) to HDL-C ratio increased by 0.18 (95% CI: 0.11, 0.25), with no change in non-HDL-C or triglycerides. Changes in HDL-C and the TC/HDL-C ratio associated with pregnancy persisted for decades, leading to altered life-course lipid trajectories. For example, parous women had a lower HDL-C than nulliparous women at the age of 50 years (-1.4 mg/dl; 95% CI: -2.3, -0.4). Adverse changes in lipids were greatest after first birth, with small changes after subsequent births, and were larger in women who did not breastfeed. Findings suggest that pregnancy is associated with long-lasting adverse changes in HDL-C, potentially setting parous women on a more atherogenic trajectory than prior to pregnancy.

Oxidative-Nitrative Stress and Poly (ADP-Ribose) Polymerase Activation 3 Years after Pregnancy

Background

Oxidative-nitrative stress and poly (ADP-ribose) polymerase activation have been previously observed in healthy and gestational diabetic pregnancies, and they were also linked to the development of metabolic diseases. The aim of the present study was to examine these parameters and their correlation to known metabolic risk factors following healthy and gestational diabetic pregnancies.

Methods

Fasting and 2 h postload plasma total peroxide level, protein tyrosine nitration, and poly (ADP-ribose) polymerase activation were measured in circulating leukocytes three years after delivery in women following healthy, "mild" (diet-treated) or "severe" (insulin-treated) gestational diabetic pregnancy during a standard 75 g OGTT. Nulliparous women and men served as control groups.

Results

Fasting plasma total peroxide level was significantly elevated in women with previous pregnancy (B = 0.52 ± 0.13; p < 0.001), with further increase in women with insulin-treated gestational diabetes (B = 0.36 ± 0.17; p < 0.05) (R² = 0.419). Its level was independently related to previous pregnancy (B = 0.47 ± 0.14; p < 0.01) and current CRP levels (B = 0.06 ± 0.02; p < 0.05) (R² = 0.306).

Conclusions

Elevated oxidative stress but not nitrative stress or poly (ADP-ribose) polymerase activation can be measured three years after pregnancy. The increased oxidative stress may reflect the cost of reproduction and possibly play a role in the increased metabolic risk observed in women with a history of severe gestational diabetes mellitus.

Common carotid artery intima-media thickness increases throughout the pregnancy cycle: a prospective cohort study

Background

High parity is associated with greater cardiovascular disease (CVD) among mid-life and older women. Prospective studies of arterial change throughout pregnancy are needed to provide insight into potential mechanisms. This study assessed vascular adaptation across pregnancy in healthy first-time pregnant women.

Methods

The Maternal Vascular Adaptation to Healthy Pregnancy Study (Pittsburgh, PA, 2010–2015) assessed 37 primigravid women each trimester, 6–8 weeks after delivery and 1–5 years postpartum, with B-mode ultrasound imaging of common carotid artery (CCA) intima-media thickness (IMT) and inter-adventitial diameter (IAD) to assess associations with physical and cardiometabolic measures.

Results

Thirty-seven women (age 28.2 ± 4.5 years, pre-pregnant BMI 24.4 ± 3.2 kg/m²) experienced uncomplicated pregnancies. After adjustment for age and pre-pregnancy BMI, mean (SE) IAD (mm) increased each trimester, from 6.38 (0.08) in the 1st trimester to 6.92 (0.09) in the 3rd trimester, and then returned to 1st trimester levels postpartum (6.35 [0.07], P <  0.001). In contrast, mean (SE) CCA IMT (mm) increased from the 2nd trimester (i.e., 0.546 [0.01]) onward, and remained higher at an average of 2.7 years postpartum (0.581 [0.02], P = 0.03). Weight partially explained changes in IAD.

Conclusions

In uncomplicated first pregnancies, IAD increased and returned to 1st trimester levels postpartum. In contrast, CCA IMT remained increased 2 years postpartum. Maternal weight explained vascular changes better than did metabolic changes. Increased postpartum CCA IMT may persist and contribute to long-term CVD risk.

Electronic supplementary material

The online version of this article (10.1186/s12884-018-1841-y) contains supplementary material, which is available to authorized users.

Cumulative effect of reproductive factors on ideal cardiovascular health in postmenopausal women: a cross-sectional study in central south China

Background

The American Heart Association developed the Life’s Simple 7 metric for defining cardiovascular health. Little is known, however, whether co-occurring reproductive factors, which affects endogenous oestrogen levels during a woman’s life, also influences ideal cardiovascular health in postmenopausal women.

Methods

Using data on a cross-sectional study with a convenience sample of 1,625 postmenopausal women (median age, 60.0 years) in a medical health checkup program at a general hospital in central south China 2013–2014, we examined the association between cumulative reproductive risk and ideal cardiovascular health in postmenopausal women. A cumulative risk score (range 0 to 4) was created by summing four reproductive risk factors (age at menarche, age at menopause, number of children, and pregnancy losses) present in each individual from binary variables in which 0 stands for favorable and 1 for less-than-favorable level. Ideal levels for each component in Life’s Simple 7 (blood pressure, cholesterol, glucose, BMI, smoking, physical activity, and diet) were used to create an ideal Life’s Simple 7 score [0–1 (low), 2, 3, 4, 5 and 6–7 (high)].

Results

Participants with earlier age at menarche (odds ratio [OR] =0.42 [95 % CI 0.26-0.48]), earlier age at menopause [0.46 (0.32-0.58)], who have more than three children (0.42 [0.38-0.56]) and have history of pregnancy losses [0.76 (0.66-0.92)] were more likely to attain low (0–1) ideal Life’s Simple 7 after adjustment for age. Participants were more likely to attain low (0–1) ideal Life’s Simple 7 as exposure to the number of reproductive risk factors increased [OR (95 % CI) of 0.52 (0.42-0.66), 0.22 (0.16-0.26), and 0.16 (0.12-0.22) for cumulative reproductive risk scores of 1, 2, and 3 or 4, respectively, each versus 0].

Conclusions

The postmenopausal Chinese women with an increasing number of reproductive risk factors were progressively less likely to attain ideal levels of cardiovascular health factors.

Nulliparity is associated with less healthy markers of subclinical cardiovascular disease in young women with overweight and obesity

OBJECTIVE

Higher parity is associated with increased subclinical cardiovascular disease (CVD) in mid-life and older women and with increased CVD risk overall. The relationship between parity, subclinical CVD, and infertility in young women with overweight and obesity has been infrequently evaluated.

METHODS

Reproductive histories were obtained in 191 (66%) young women with overweight and obesity (BMI 25-39.9 kg/m(2) ) participating in a weight loss trial. Baseline carotid intima-media thickness (IMT) and inter-adventitial diameter (IAD) were assessed via B-mode ultrasound. Linear regression was used to estimate the relationship between parity and carotid measures, adjusted for demographic, cardiovascular, and reproductive risk factors.

RESULTS

Nulliparous women (n = 70, age 34.9 ± 7.1) had increased common carotid IAD (0.230 mm, SE 0.08, P = 0.003) and mean common carotid artery (CCA) IMT (0.031 mm, SE 0.01, P = 0.007) compared with parous women (n = 102, age 39.5 ± 4.9), persisting after adjustment for age, race, and CVD risk factors. No other reproductive factors were statistically significantly associated.

CONCLUSIONS

Nulliparity is associated with markers of less healthy carotid arteries in a sample of disease-free 25- to 45-year-old women with overweight or obesity. This may represent a beneficial effect of pregnancy or indicate overall better health in women with overweight/obesity who are capable of childbearing.

Association between number of live births and markers of subclinical atherosclerosis: The Dallas Heart Study

AIMS

Higher parity has been associated with increased maternal risk of cardiovascular disease, but the mechanism is not well delineated. Whether the number of live births is associated with coronary and aortic subclinical atherosclerosis has not been fully evaluated.

METHODS AND RESULTS

Women from the Dallas Heart Study, a multiethnic population-based cohort of subjects aged 30-65 years, were included if they had data on self-reported live births and coronary artery calcium (CAC) measured by computed tomography or aortic wall thickness (AWT) by MRI. Coronary artery calcium was positive if >10 Agatston units, and aortic wall thickness if greater than the 75(th) percentile reference point for age and gender. Among the 1644 women included in the study, the mean age was 45 years and 55% were Black. Sequential multivariable models were done adjusting for age, race, traditional cardiovascular risk factors, body mass index, income, education, hormone replacement therapy, oral contraceptives, and physical activity. Using women with 2-3 live births as the reference, those with four or more live births had an increased prevalence of elevated coronary artery calcium (odds ratio (OR) 2.2, 95% confidence interval (CI) 1.28-3.65) and aortic wall thickness (OR 1.6, 95% CI 1.04-2.41). Women with 0-1 live births also had increased coronary artery calcium (OR 1.9, 95% CI 1.16-3.03) and aortic wall thickness (OR 1.5, 95% CI 1.05-2.09) after multivariable adjustment.

CONCLUSION

The number of live births is associated with subclinical coronary and aortic atherosclerosis, with an apparent U-shaped relationship. Further studies are needed to confirm this association and explore the biological underpinnings of these findings.

Correlates of cardiovascular disease risk scores in women in Riyadh, Kingdom of Saudi Arabia

Saudi Arabia has a high prevalence of obesity and physical inactivity. We measured cardiovascular (CVD) risk scores and determined the factors associated with them in women in Riyadh, Saudi Arabia. A cross-sectional study using a self-administered questionnaire was conducted on 291 women aged ≥ 30 years. Information was collected on socio-demographics and physical health status. Anthropometric and blood pressure measurements were taken. Physical activity was measured using Kaiser's Physical Activity Survey and Godin's Leisure Time Exercise questionnaire. CVD risk scores were calculated using the non-laboratory-based Framingham Risk (FRS) prediction model for primary care. FRS scores ranged from 0.50 to 21.9. A total of 2.7% (n = 8) of women had a high FRS score (>20), 5.5% (n = 16) had intermediate scores (11-20), and 91.8% (n = 267) of women had low scores (<10) CVD risk scores. Multiple linear regression results indicated that a one-unit change in physical activity (household/caregiver index), strenuous exercise, waist circumference, number of children, television watching, and knee pain were significantly associated with -0.20 (p < .01), -0.12 (p = .03), 0.19 (p = .001), 0.29 (p < .01), 0.13 (p = .04), and 0.11 (p = .05) unit change in CVD risk scores, respectively. Household activities and strenuous exercise had a protective role in females in relation to CVD risk. Programs recommending physical activity at all levels should be encouraged.

Reproductive factors, intima media thickness and carotid plaques in a cross-sectional study of postmenopausal women enrolled in the population-based KORA F4 study

BACKGROUND

Reproductive events may affect the onset of chronic diseases. We examined the possible association between reproductive parameters and intima media thickness (IMT) or carotid plaques in the common carotid artery in a population-based sample.

METHODS

This cross-sectional study analysed data of 800 postmenopausal women aged 50 to 81 years of the population-based KORA F4 study, conducted between 2006 and 2008 in Southern Germany. Reproductive parameters were obtained by standardised interviews.

RESULTS

Age at menarche below 12 years compared to 12-15 years was significantly associated with carotid plaques (age-adjusted OR 2.23, 95% CI 1.13-4.43, p-value 0.018, multivariable adjusted 2.11, 1.05-4.26, 0.037), but not with IMT. Ever use of hormone replacement therapy was inversely associated with carotid plaques (age-adjusted 0.60, 0.44-0.81, p = 0.001, multivariable-adjusted 0.62, 0.45-0.86, 0.003) and IMT in the age-adjusted model (mean 0.89, 95% CI 0.88-0.90, p = 0.033) but not in the multivariable-adjusted model (mean 0.89, 95% CI 0.88-0.90, p = 0.075). Parity, age at menopause, time since menopause, duration of fertile period, current use of hormone replacement therapy, ever use of oral contraceptives, hysterectomy, bilateral oophorectomy, hot flashes and depressive mood in relation to the menopausal transition were not associated with carotid plaques or IMT.

CONCLUSION

Our study showed, that there may be an independent association between the reproductive parameters age at menarche and ever use of hormone replacement therapy with carotid plaques in the common carotid artery, but not with IMT. Further research, especially in studies with prospective population-based study design, is necessary to assess in detail what events in women's life lead to increased IMT or CP.

Maternal serum cholesterol levels are elevated from the 1st trimester of pregnancy: a cross-sectional study

Cholesterol is monitored in the non-pregnant adult population, where normal values are established. Although reported to be elevated in pregnancy, cholesterol is neither routinely measured nor treated. We aimed to investigate cholesterol levels throughout pregnancy and to establish reference values for cholesterol in healthy pregnant women. This was a cross-sectional analysis of serum cholesterol in healthy women with an uncomplicated singleton pregnancy. Pregnant women attending for antenatal care were recruited and cholesterol levels assayed at 12, 20, 28 and 36 weeks' gestation and on day 1-3 postpartum. A total of 222 women were recruited. The majority (95%) were white Irish, with a median age of 31 years (range 16-46). Median BMI was 25.9 kg/m2 (range 18-40) and 16% were smokers. Cholesterol levels were elevated in all trimesters of pregnancy, with median values from 1st trimester raised outside the non-pregnant adult range. High-density lipoprotein (HDL) levels ranged from 0.9 to 3.7 mmol/l and low-density lipoprotein (LDL) levels ranged from 1.3 to 6.1 mmol/l. Fasting, smoking and obesity did not have any significant effects on results. Total and LDL-cholesterol levels were raised throughout pregnancy. Levels were above non-pregnant adult ranges as early as the 1st trimester. The implications of this on fetus and mother are undetermined and deserve further investigation.

Estrogen signaling in microvascular arteries: parturition reduces vasodilation by reducing 17β-estradiol and nNOS

Few studies have examined the potential effects of childbirth on the responses of the female vasculature--especially the resistance microvasculature of non-reproductive tissues. In the present study we have investigated the response of mesenteric microvascular resistance vessels to estrogen (E2), an important vasoactive hormone. Vessels were obtained from either nulliparous or postpartum female Sprague-Dawley rats, and isometric tension studies were performed. We found that E2 induced a concentration-dependent, endothelium-independent relaxation of microvessels precontracted with 10(-5) M phenylephrine; however, E2-induced relaxation was reduced by nearly half in vessels from postpartum animals compared to nulliparous controls. Inhibiting nitric oxide synthase activity with 10(-4) M L-NMMA or L-NPA (which exhibits selectivity for type 1 or nNOS) attenuated the relaxation effect of E2 on arteries from nulliparous animals. In contrast, L-NPA had little effect on arteries from postpartum animals, suggesting a reduced influence of nNOS after parturition. Moreover, expression of nNOS protein in microvessels was decreased 39% in the postpartum state compared to arteries from nulliparous animals. We propose that the impaired E2-induced relaxation response of microvessels from postpartum animals reflects a downregulation of NO production due to lower nNOS expressed in vascular smooth muscle cells. We measured a 73% decrease in serum E2 levels in the postpartum state compared to nulliparous animals. Because E2 has been shown to increase nNOS protein expression, we propose that lower E2 levels after parturition decrease expression of nNOS, leading to a reduced vasodilatory capacity of resistance microvessels.

Cholesterol in pregnancy: a review of knowns and unknowns

Cholesterol forms part of every cell in the human body, and also helps make and metabolize hormones, bile acids and vitamin D. Human plasma cholesterol levels are determined by production in the liver and by dietary intake. Lipoproteins carry cholesterol around the body, and facilitate it crossing the placenta. Cholesterol is carefully monitored in the non-pregnant adult population, where its association with atherosclerosis and cardiovascular disease is well understood. Although it is known that cholesterol rises in pregnancy, at present it is not routinely measured or treated. The effects of maternal high cholesterol on pregnancy and on fetal development are not yet fully understood. However, a growing body of evidence from animal and human studies suggests adverse consequences of high cholesterol levels in pregnancy.

Number of children and change in markers of metabolic health over 9-years in men and women. Data from the DESIR study

AIM

Parity is associated with an increased risk of coronary heart disease and type 2 diabetes, possibly mediated by long-term modification of metabolic health. Studying associations between the number of children with health and disease in men in addition to women allows for differentiation between the social and lifestyle influences of child-rearing, and the biological influences of childbearing. We sought to determine whether the number of children is associated with the incidence of raised fasting glucose (fasting plasma glucose≥6.1 mmol/L) and changes in glucose, insulin, insulin resistance and β-cell function over 9-years.

METHODS

Analysis of 1798 women and 1737 men from the DESIR study.

RESULTS

The number of children was associated with change in fasting glucose for women (P(trend)=0.02) and men (P(trend)=0.03), and increased incidence of raised fasting glucose by 30% (95% CI: 15, 47%) per child for men, but not women (3% [95% CI: -8, 15%]). There was a J-shaped association between number of children and change in insulin (P=0.01) and insulin resistance (P=0.005) for women, and a reduction in β-cell function in parous women (P=0.07). Men with children had increases in insulin (P=0.02), insulin resistance (P=0.02), and β-cell function (P=0.07).

CONCLUSIONS

The number of children a person has is associated with changes in metabolic health indices long after childbirth for both men and women. The distinct gender differences in deterioration of metabolic health indices emphasize that childbearing and child-rearing are likely to have differential influences on metabolic health.