Hypertensive disorders during pregnancy are associated with reduced severe intraventricular hemorrhage in very-low-birth-weight infants

Maternal Hypertension and Adverse Neurodevelopment in a Cohort of Preterm Infants

Importance

Whether maternal hypertensive disorders of pregnancy (HDP) confer independent neurodevelopmental deficit risks in premature infants is controversial. Previous studies are limited by inadequate confounding variable control and other biases.

Objective

To evaluate the associations between maternal HDP, especially preeclampsia, and neurodevelopmental outcomes of preterm infants at 2 years' corrected age.

Design, Setting, and Participants

Regional prospective cohort study of 395 preterm infants (≤32 weeks' gestation) from 5 level III and IV southeast Ohio neonatal intensive care units from September 2016 to November 2019. Data analysis was conducted in August 2022.

Exposure

HDP, defined by maternal diagnosis of chronic or gestational hypertension or preeclampsia during pregnancy.

Main Outcomes and Measures

Structural brain magnetic resonance imaging was performed at term-equivalent age. Neurodevelopment was assessed by Bayley Scales of Infant and Toddler Development (BSID), Third Edition, between 22 and 26 months' corrected age. Multivariable regression was used to identify the independent association of HDP and preeclampsia on cognitive (primary outcome), language, and motor development, controlling for several confounders. Mediation analyses were performed to understand if the association with HDP was mediated by its association with birth weight or brain abnormalities.

Results

In a cohort of 395 infants, the median (IQR) gestational age was 29.6 (27.6-31.4) weeks, birth weight was 1230 (950-1628) g, and 210 (53.2%) were male. Of these, 170 (43%) were HDP-exposed, of which 104 of 170 (61%) were exposed to preeclampsia. A total of 341 children (87%) completed the BSID. In adjusted analyses, HDP exposure was negatively associated with BSID cognitive scores (-3.69; 95% CI, -6.69 to -0.68; P = .02) and language scores (-4.07; 95% CI, -8.03 to -0.11; P = .04). Preeclampsia exposure showed similarly negative but greater associations for BSID scores (-4.85; 95% CI, -8.63 to -1.07; P = .01 for cognitive and -6.30; 95% CI, -11.49 to -1.09; P = .02 for language scores). Mediation analysis revealed that the association between HDP and cognitive scores was partially mediated by its adverse association with brain abnormalities at term-equivalent age (24% of the total effect; -0.82; 95% CI, -1.72 to -0.13; P = .02).

Conclusions and Relevance

In this preterm cohort study, maternal HDP was independently associated with adverse cognitive and language development, with accentuated associations observed in preeclampsia-exposed preterm infants, emphasizing the clinical importance of recognizing HDP as a risk, enabling targeted risk management strategies for closer monitoring and aggressive early intervention in affected populations.

Hypertensive Disorders of Pregnancy and Risk of Early Brain Abnormalities on Magnetic Resonance Imaging at Term among Infants Born at ≤32 Weeks' Gestational Age

OBJECTIVE

To evaluate the proximal effects of hypertensive disorders of pregnancy (HDP) on a validated measure of brain abnormalities in infants born at ≤32 weeks' gestational age (GA) using magnetic resonance imaging at term-equivalent age.

STUDY DESIGN

In a multisite prospective cohort study, 395 infants born at ≤32 weeks' GA, underwent 3T magnetic resonance imaging scan between 39 and 44 weeks' postmenstrual age. A single neuroradiologist, blinded to clinical history, evaluated the standardized Kidokoro global brain abnormality score as the primary outcome. We classified infants as HDP-exposed by maternal diagnosis of chronic hypertension, gestational hypertension, pre-eclampsia, or eclampsia. Linear regression analysis identified the independent effects of HDP on infant brain abnormalities, adjusting for histologic chorioamnionitis, maternal smoking, antenatal steroids, magnesium sulfate, and infant sex. Mediation analyses quantified the indirect effect of HDP mediated via impaired intrauterine growth and prematurity and remaining direct effects on brain abnormalities.

RESULTS

A total of 170/395 infants (43%) were HDP-exposed. Adjusted multivariable analyses revealed HDP-exposed infants had 27% (95% CI 5%-53%) higher brain abnormality scores than those without HDP exposure (P = .02), primarily driven by increased white matter injury/abnormality scores (P = .01). Mediation analyses showed HDP-induced impaired intrauterine growth significantly (P = .02) contributed to brain abnormality scores (22% of the total effect).

CONCLUSIONS

Maternal hypertension independently increased the risk for early brain injury and/or maturational delays in infants born at ≤32 weeks' GA with an indirect effect of 22% resulting from impaired intrauterine growth. Enhanced prevention/treatment of maternal hypertension may mitigate the risk of infant brain abnormalities and potential neurodevelopmental impairments.

A simple scoring system for prediction of IVH in very-low-birth-weight infants

BACKGROUND

To develop a simple scoring system to predict either any or severe IVH in VLBW infants.

METHODS

In this retrospective cohort study, 923 VLBW infants were randomly divided into derivation (n = 431) and validation (n = 492) cohorts. After stepwise multivariable logistic regression analyses, a risk score was assigned to independent predictors.

RESULTS

The overall rates of any and severe IVH were 22.9% and 9.9%. Gestational age, maternal race, location of birth and sex were independent predictors of any IVH (AUC 0.75 in derivation cohort and 0.69 for validation cohort). Birth weight, Apgar score at 1 minute, location of birth and sex were independent predictors of severe IVH (AUC 0.84 in derivation cohort and 0.77 for validation cohort). For any IVH, infants in the high-risk category (total score 4 or 5) had > 50% likelihood of any IVH with a negative predictive value of 82.6%. For severe IVH, the total risk score ranged from 0-8, and infants in high-risk category (total score 6-8) had 30% likelihood of severe IVH with a negative predictive value of 94.9%.

CONCLUSION

We report an easy to calculate, validated scoring system with a high NPV to identify VLBW infants at highest risk of IVH.

IMPACT

We report a simple validated scoring system with a high NPV for prediction of IVH in VLBW infants. The variables in the proposed model are available at birth and unlikely to be influenced by provider bias. This scoring system can identify infants at risk of any and severe IVH, while most previous models predict only severe IVH. This scoring system does not require access to web-based resources. This scoring system can help in employing prevention strategies only for infants at highest risk of IVH and thus eliminate the risks of interventions in a large majority of VLBW infants.

Bronchopulmonary Dysplasia in Extremely Premature Infants: A Scoping Review for Identifying Risk Factors

BACKGROUND

Over the years, bronchopulmonary dysplasia (BPD) affects the pulmonary function of infants, resulting in chronic health burdens for infants and their families. The aim of this scoping review was to screen available evidence regarding perinatal risk factors associated with the development and severity of BPD.

METHODS

The eligibility criteria of the studies were year of publication between 2016 and 2021; setting of a developed country; English or Japanese as the study language; and randomized controlled, cohort, or case-control design. The titles and abstracts of the studies were screened by independent reviewers.

RESULTS

Of 8189 eligible studies, 3 were included for severe BPD and 26 were included for moderate BPD. The risk factors for severe BPD were male sex, iatrogenic preterm birth, maternal hypertensive disorders of pregnancy (HDP), low gestational age, small-for-gestational-age (SGA) birth weight, mechanical ventilation on day 1, and need for patent ductus arteriosus (PDA) management. The risk factors for moderate or severe BPD included male sex, premature rupture of membranes, clinical chorioamnionitis, maternal HDP, SGA birth weight, bubbly/cystic appearance on X-ray, and PDA management.

CONCLUSIONS

We identified several risk factors for BPD. We plan to confirm the validity of the new classification using the existing dataset.

Development of an integrated risk scale for prediction of shunt placement after neonatal intraventricular hemorrhage

OBJECTIVE

Neonatal intraventricular hemorrhage (IVH) is a major cause of mortality and morbidity, particularly following premature birth. Even after the acute phase, posthemorrhagic hydrocephalus is a long-term complication, frequently requiring permanent ventriculoperitoneal shunt (VPS) placement. Currently, there are no risk classification methods integrating the constellation of clinical data to predict short- and long-term prognosis in neonatal IVH. To address this need, the authors developed a two-part machine learning approach for predicting short- and long-term outcomes after diagnosis of neonatal IVH. Integrating both maternal and neonatal characteristics, they developed a binary classifier to predict short-term mortality risk and a clinical scale to predict the long-term risk of VPS placement.

METHODS

Neonates with IVH were identified from the Optum Clinformatics Data Mart administrative claims database. Matched maternal and childbirth characteristics were obtained for all patients. The primary endpoints of interest were short-term (30 day) mortality and long-term VPS placement. Classification of short-term mortality risk was evaluated using 5 different machine learning approaches and the best-performing method was validated using a withheld validation subset. Prediction of long-term shunt risk was performed using a multivariable Cox regression model with stepwise variable selection, which was subsequently converted to an easily applied integer risk scale.

RESULTS

A total of 5926 neonates with IVH were identified. Most patients were born before 32 weeks' gestation (67.2%) and with low birth weight (81.2%). Empirical 30-day mortality risk was 10.9% across all IVH grades and highest among grade IV IVH (34.3%). Among the neonates who survived > 30 days, actuarial 12-month postdiagnosis risk of shunt placement was 5.4% across all IVH grades and 31.3% for grade IV IVH. The optimal short-term risk classifier was a random forest model achieving an area under the receiver operating characteristic curve of 0.882 with important predictors ranging from gestational age to diverse comorbid medical conditions. Selected features for long-term shunt risk stratification were IVH grade, respiratory distress syndrome, disseminated intravascular coagulation, and maternal preeclampsia or eclampsia. An integer risk scale, termed the Shunt Prediction After IVH in Neonates (SPAIN) scale, was developed from these 4 features, which, evaluated on withheld cases, demonstrated improved risk stratification compared with IVH grade alone (Harrell's concordance index 0.869 vs 0.852).

CONCLUSIONS

In a large cohort of neonates with IVH, the authors developed a two-pronged, integrated, risk classification approach to anticipate short-term mortality and long-term shunt risk. The application of such approaches may improve the prognostication of outcomes and identification of higher-risk individuals who warrant careful surveillance and early intervention.

Mothers with hypertensive disorders of pregnancy increased risk of periventricular leukomalacia in extremely preterm or extremely low birth weight infants: A propensity score analysis

BACKGROUND

At present, the conclusions about the impact of hypertensive disorders of pregnancy (HDP) on the clinical outcomes of preterm infants are inconsistent. This study used the propensity score matching (PSM) analysis to evaluate the effect of HDP on clinical outcomes of extremely preterm or extremely low birth weight (EP/ELBW) infants.

METHODS

Retrospective analysis was performed on the EP/ELBW infants discharged from 26 tertiary neonatal intensive care units or died during hospitalization from 2008 to 2017, who were divided into HDP group and non-HDP group. The six covariates including sex, gestational age, birth weight, twin or multiple pregnancy, antenatal steroids administration, and conception method were matched through the PSM method at a ratio of 1:1. The survival rate at discharge and the major clinical complications were compared between the two groups.

RESULTS

After matching the six covariates, compared with the non-HDP group, there was no significant difference in the survival rate at discharge (64 vs. 63.2%, p > 0.05), the incidence of bronchopulmonary dysplasia (BPD) or moderate to severe BPD in the HDP group (58.3 vs. 54.9%, p > 0.05; 5.2 vs. 6.2%, p > 0.05). The incidence of periventricular leukomalacia (PVL) in the HDP group was significantly increased (5.7 vs. 1.9%, p < 0.05).

CONCLUSIONS

HDP increased the risk of PVL in EP/ELBW infants, but had no significant effect on the survival rate at discharge, or the occurrence of other complications.