Effect of maternal age on cardiac adaptation in pregnancy

Do maternal haemodynamics have a causal influence on treatment for gestational diabetes?

BACKGROUND

Arterial stiffening is believed to contribute to the worsening of insulin resistance, and factors which are associated with needing pharmacological treatment of gestational diabetes (GDM), such as maternal obesity or advanced age, are associated with impaired cardiovascular adaptation to pregnancy. In this observational study, we aimed to investigate causal relationships between maternal haemodynamics and treatment requirement amongst women with GDM.

METHODS

We assessed maternal haemodynamics in women with GDM, comparing those who remained on dietary treatment with those who required pharmacological management. Maternal haemodynamics were assessed using the Arteriograph® (TensioMed Ltd, Budapest, Hungary) and the NICOM® non-invasive bio-reactance method (Cheetah Medical, Portland, Oregon, USA). A graphical causal inference technique was used for statistical analysis.

RESULTS

120 women with GDM were included in the analysis. Maternal booking BMI was identified as having a causative influence on treatment requirement, with each unit increase in BMI increasing the odds of needing metformin and/or insulin therapy by 12% [OR 1.12 (1.02 - 1.22)]. The raw values of maternal heart rate (87.6 ± 11.7 vs. 92.9 ± 11.90 bpm, p = 0.014) and PWV (7.8 ± 1.04 vs. 8.4 ± 1.61 m/s, p = 0.029) were both significantly higher amongst the women requiring pharmacological management, though these relationships did not remain significant in causal logistic regression.

CONCLUSIONS

Maternal BMI at booking has a causal, rather than simply associational, relationship on the need for pharmacological treatment of GDM. No significant causal relationships were found between maternal haemodynamics and the need for pharmacological treatment.

Preterm birth risk stratification through longitudinal heart rate and HRV monitoring in daily life

Preterm birth (PTB) remains a global health concern, impacting neonatal mortality and lifelong health consequences. Traditional methods for estimating PTB rely on electronic health records or biomedical signals, limited to short-term assessments in clinical settings. Recent studies have leveraged wearable technologies for in-home maternal health monitoring, offering continuous assessment of maternal autonomic nervous system (ANS) activity and facilitating the exploration of PTB risk. In this paper, we conduct a longitudinal study to assess the risk of PTB by examining maternal ANS activity through heart rate (HR) and heart rate variability (HRV). To achieve this, we collect long-term raw photoplethysmogram (PPG) signals from 58 pregnant women (including seven preterm cases) from gestational weeks 12-15 to three months post-delivery using smartwatches in daily life settings. We employ a PPG processing pipeline to accurately extract HR and HRV, and an autoencoder machine learning model with SHAP analysis to generate explainable abnormality scores indicative of PTB risk. Our results reveal distinctive patterns in PTB abnormality scores during the second pregnancy trimester, indicating the potential for early PTB risk estimation. Moreover, we find that HR, average of interbeat intervals (AVNN), SD1SD2 ratio, and standard deviation of interbeat intervals (SDNN) emerge as significant PTB indicators.

Guidelines for assessing maternal cardiovascular physiology during pregnancy and postpartum

Maternal mortality rates are at an all-time high across the world and are set to increase in subsequent years. Cardiovascular disease is the leading cause of death during pregnancy and postpartum, especially in the United States. Therefore, understanding the physiological changes in the cardiovascular system during normal pregnancy is necessary to understand disease-related pathology. Significant systemic and cardiovascular physiological changes occur during pregnancy that are essential for supporting the maternal-fetal dyad. The physiological impact of pregnancy on the cardiovascular system has been examined in both experimental animal models and in humans. However, there is a continued need in this field of study to provide increased rigor and reproducibility. Therefore, these guidelines aim to provide information regarding best practices and recommendations to accurately and rigorously measure cardiovascular physiology during normal and cardiovascular disease-complicated pregnancies in human and animal models.

Subphenotypes of severe early-onset pre-eclampsia at hospital admission. A Latin American single-center exploratory latent class analysis

OBJECTIVES

To identify distinct subphenotypes of severe early-onset pre-eclampsia in Latin America and analyze biomarker and hemodynamic trends between subphenotypes after hospital admission.

METHODS

A single-center prospective cohort study was conducted in Colombia. The latent class analysis identified subphenotypes using clinical variables, biomarkers, laboratory tests, and maternal hemodynamics. Class-defining variables were restricted to measurements at and 24 h after admission. Primary and secondary outcomes were severe maternal and perinatal complications.

RESULTS

Among 49 patients, two subphenotypes were identified: Subphenotype 1 (34.7%) had a higher likelihood of an sFlt-1/PlGF ratio ≤ 38, maternal age > 35, and low probability of TPR > 1400, CO <8, and IUGR; Subphenotype 2 (65.3%) had a low likelihood of an sFlt-1/PlGF ratio < 38, maternal age > 35, and high probability of TPR > 1400, CO <8, and IUGR. At 24 h postadmission, 64.7% of subphenotype 1 patients changed to subphenotype 2, while 25% of subphenotype 2 patients were reclassified as subphenotype 1. Subphenotype 1 displayed significant changes in CO and TPR, while subphenotype 2 did not. Maternal complications were more prevalent in subphenotype 2, with an odds ratio of 5.3 (95% CI: 1.3-22.0; P = 0.02), but no significant differences in severe neonatal complications were observed.

CONCLUSIONS

We identified two distinct subphenotypes in a Latin American cohort of patients with severe early-onset pre-eclampsia. Subphenotype 2, characterized by higher TPR, sFlt-1, and serum creatinine and lower CO and PlGF at admission, was associated with worse maternal outcomes and appeared less modifiable after in-hospital treatment.

Linking Electronic Health Records With Wearable Technology From the All of Us Research Program

OBJECTIVE

To evaluate the feasibility of using electronic health records (EHRs) and wearable data to describe patterns of longitudinal change in day-level heart rate before, during, and after pregnancy and how these patterns differ by age and body mass index.

DESIGN

Descriptive secondary analysis feasibility study using data from the National Institutes of Health All of Us Research Program.

SETTING

United States.

PARTICIPANTS

Women (N = 89) who had a birth or length of gestation code in the EHR and at least 60 days of Fitbit heart rate data during pregnancy.

METHODS

We estimated pregnancy-related episodes using EHR codes. Time consisted of five 3-month periods: before pregnancy, first trimester, second trimester, third trimester, and after birth. We analyzed data using descriptive statistics and locally estimated scatterplot smoothing.

RESULTS

An average of 330 days (SD = 112) of Fitbit heart rate data (29,392 days) were available from participants. During pregnancy, distinct peaks in heart rate occurred during the first trimester (6% increase) and third trimester (15% increase).

CONCLUSION

Future researchers can examine whether longitudinal timing and patterns of heart rate from wearable devices could be leveraged to detect health problems early in pregnancy.

Longitudinal maternal cardiac function in hypertensive disorders of pregnancy

BACKGROUND

Compared with gestational hypertension, preeclampsia has traditionally been considered the worse end of the spectrum of hypertensive disorders of pregnancy. It is associated with worse pregnancy outcomes and future cardiovascular morbidities. Both hypertensive disorders may be associated with cardiac maladaptation in pregnancy. However, previous studies were limited by small numbers and a paucity of longitudinal data and unaccounted for the contribution of maternal characteristics that can affect hemodynamics.

OBJECTIVE

This study aimed to assess, in an unselected population, the maternal cardiac adaptation in normotensive and hypertensive pregnancies after controlling for important maternal characteristics that affect maternal cardiac function and the interaction among these covariates.

STUDY DESIGN

This was a prospective, multicenter longitudinal study of maternal hemodynamics, assessed by a noninvasive bioreactance technology, measured at 11 0/7 to 13 6/7, 19 0/7 to 24 0/7, 30 0/7 to 34 0/7, and 35 0/7 to 37 0/7 weeks of gestation in 3 groups of women. Group 1 was composed of women with preeclampsia (n=45), group 2 was composed of women with gestational hypertension (n=61), and group 3 was composed of normotensive women (n=1643). A multilevel linear mixed-effects model was performed to compare the repeated measures of hemodynamic variables controlling for maternal age, height, weight, weight gain, race, previous obstetrical history, and birthweight.

RESULTS

After adjusting for confounders that significantly affect maternal hemodynamics, both group 1 and group 2, compared with group 3, had pathologic cardiac adaptation. Group 1, compared with group 3, demonstrated hyperdynamic circulation with significantly higher cardiac output driven by greater stroke volume in the first trimester of pregnancy. As the pregnancies progressed to after 20 0/7 weeks of gestation, this hyperdynamic state transitioned to hypodynamic state with low cardiac output and high peripheral vascular resistance. Group 2, compared with group 3, had no significant differences in cardiac output, stroke volume, and heart rate before 20 0/7 weeks of gestation but thereafter demonstrated a continuous decline in cardiac output and stroke volume, similar to group 1. Both groups 1 and 2, compared with group 3, had persistently elevated mean arterial pressure and uterine artery pulsatility index throughout pregnancy.

CONCLUSION

After adjusting for confounders that affect maternal hemodynamics in an unselected pregnant population, women with preeclampsia and gestational hypertension, compared with normotensive women, demonstrated similar cardiac maladaptation. This pathologic profile was evident after 20 0/7 weeks of gestation and at least 10 weeks before the clinical manifestation of the disease.

Impact of maternal height, weight at presentation and gestational weight gain on cardiac adaptation in pregnancy

OBJECTIVE

To compare longitudinal maternal hemodynamic changes throughout gestation between different groups stratified according to weight at presentation and assess the relative influence of height, weight at presentation and gestational weight gain on cardiac adaptation.

METHODS

This was a prospective, longitudinal study assessing maternal hemodynamics using bioreactance technology at 11 + 0 to 13 + 6, 19 + 0 to 24 + 0, 30 + 0 to 34 + 0 and 35 + 0 to 37 + 0 weeks' gestation. Women were divided into three groups according to maternal weight at presentation at the first visit at 11 + 0 to 13 + 6 weeks: Group 1, &lt; 60.0 kg (n = 421); Group 2, 60.0-79.7 kg (n = 904); Group 3, &gt; 79.7 kg (n = 427). A multilevel linear mixed-effects model was used to compare the repeated measures of hemodynamic variables, correcting for demographics, medical and obstetric history, pregnancy complications, maternal weight and time of evaluation. The linear mixed-effects model was then repeated using maternal height, weight at presentation and gestational weight gain Z-scores, and the standardized coefficients were used to evaluate the relative impact of each of these demographic parameters on longitudinal changes of maternal hemodynamics.

RESULTS

Compared with Group 1, women in Group 3 demonstrated higher cardiac output (CO), heart rate (HR) and mean arterial pressure (MAP) throughout pregnancy. Groups 2 and 3 had higher stroke volume (SV) than Group 1 at the first visit, but their SV plateaued between the first and second visits and demonstrated an earlier significant decrease from the second visit to the third visit when compared with Group 1. Compared with Groups 1 and 2, there was a higher prevalence of pre-eclampsia, gestational hypertension and gestational diabetes in Group 3. Maternal height was the most important contributor to CO, peripheral vascular resistance (PVR), SV and HR, while weight at presentation was the most important contributor to MAP. Gestational weight gain was the second most important characteristic influencing the longitudinal changes of PVR and SV.

CONCLUSIONS

Women with greater weight at presentation have a pathological hemodynamic profile, with higher CO, HR and MAP compared to women with lower weight at presentation. Height is the main determinant of CO, SV, HR and PVR, weight is the main determinant of MAP, and gestational weight gain is the second most important determinant of SV and PVR. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.