Risk factors for seizures in the vigorous term neonate: A population-based register study of singleton births in Sweden

Nonreassuring fetal status during labor and offspring's childhood neurodevelopment at 3 years of age: The Japan Environment and Children's Study

OBJECTIVE

Although prior attempts have failed to identify the beneficial effects of intensive fetal monitoring on cerebral palsy, the association between nonreassuring fetal status (NRFS) during labor and the incidence of long-term neurodevelopmental delays in offspring remains unclear. This study aimed to evaluate this association using a nationwide birth cohort.

METHODS

Data from 72 869 women with singleton deliveries at and after 37 weeks of gestation from the Japan Environment and Children's Study (2011-2014) were analyzed. Multivariable logistic regression models were used to analyze the odds ratios (ORs) for neurodevelopmental delays using the Ages & Stages Questionnaire (Third Edition) in offspring aged 3 years.

RESULTS

The adjusted ORs for personal-social problems were 1.52 (95% confidence interval [CI], 1.06-2.16) for offspring delivered vaginally by nulliparous mothers and 1.51 (95% CI, 1.05-2.18) (for males, 1.70 [95% CI, 1.15-2.50]) for those delivered via cesarean section. No significant changes in adjusted ORs for neurodevelopmental delays were observed among participants without neonatal Apgar scores (ASs) <7 and without umbilical arterial pH (UmA-pH) <7.20.

CONCLUSION

NRFS during labor was associated with an increased incidence of personal-social problems in offspring aged 3 years. However, this association was not confirmed after excluding participants with neonatal ASs <7 and UmA-pH <7.20. The association between NRFS and offspring's neurodevelopmental delays might vary based on delivery settings, offspring sex, and short-term neonatal outcomes.

Anti-seizure medication-induced developmental cell death in neonatal rats is unaltered by history of hypoxia

BACKGROUND

Many anti-seizure medications (ASMs) trigger neuronal cell death when administered during a confined period of early life in rodents. Prototypical ASMs used to treat early-life seizures such as phenobarbital induce this effect, whereas levetiracetam does not. However, most prior studies have examined the effect of ASMs in naïve animals, and the degree to which underlying brain injury interacts with these drugs to modify cell death is poorly studied. Moreover, the degree to which drug-induced neuronal cell death differs as a function of sex is unknown.

METHODS

We treated postnatal day 7 Sprague Dawley rat pups with vehicle, phenobarbital (75 mg/kg) or levetiracetam (200 mg/kg). Separate groups of pups were pre-exposed to either normoxia or graded global hypoxia. Separate groups of males and females were used. Twenty-four hours after drug treatment, brains were collected and processed for markers of cell death.

RESULTS

Consistent with prior studies, phenobarbital, but not levetiracetam, increased cell death in cortical regions, basal ganglia, hippocampus, septum, and lateral thalamus. Hypoxia did not modify basal levels of cell death. Females - collapsed across treatment and hypoxia status, displayed a small but significant increase in cell death as compared to males in the cingulate cortex, somatosensory cortex, and the CA1 and CA3 hippocampus; these effects were not modulated by hypoxia or drug treatment.

CONCLUSION

We found that a history of graded global hypoxia does not alter the neurotoxic profile of phenobarbital. Levetiracetam, which does not induce cell death in normal developing animals, maintained a benign profile on the background of neonatal hypoxia. We found a sex-based difference, as female animals showed elevated levels of cell death across all treatment conditions. Together, these data address several long-standing gaps in our understanding of the neurotoxic profile of antiseizure medications during early postnatal development.

Effects of season, daytime, sex, and stress on the incidence, latency, frequency, severity, and duration of neonatal seizures in a rat model of birth asphyxia

Neonatal seizures are common in newborn infants after birth asphyxia. They occur more frequently in male than female neonates, but it is not known whether sex also affects seizure severity or duration. Furthermore, although stress and diurnal, ultradian, circadian, or multidien cycles are known to affect epileptic seizures in adults, their potential impact on neonatal seizures is not understood. This prompted us to examine the effects of season, daytime, sex, and stress on neonatal seizures in a rat model of birth asphyxia. Seizures monitored in 176 rat pups exposed to asphyxia on 40 experimental days performed over 3 years were evaluated. All rat pups exhibited seizures when exposed to asphyxia at postnatal day 11 (P11), which in terms of cortical development corresponds to term human babies. A first examination of these data indicated a seasonal variation, with the highest seizure severity in the spring. Sex and daytime did not affect seizure characteristics. However, when rat pups were subdivided into animals that were exposed to acute (short-term) stress after asphyxia (restraint and i.p. injection of vehicle) and animals that were not exposed to this stress, the seizures in stress-exposed rats were more severe but less frequent. Acute stress induced an increase in hippocampal microglia density in sham-exposed rat pups, which may have an additive effect on microglia activation induced by asphyxia. When seasonal data were separately analyzed for stress-exposed vs. non-stress-exposed rat pups, no significant seasonal variation was observed. This study illustrates that without a detailed analysis of all factors, the data would have erroneously indicated significant seasonal variability in the severity of neonatal seizures. Instead, the study demonstrates that even mild, short-lasting postnatal stress has a profound effect on asphyxia-induced seizures, most likely by increasing the activity of the hypothalamic-pituitary-adrenal axis. It will be interesting to examine how postnatal stress affects the treatment and adverse outcomes of birth asphyxia and neonatal seizures in the rat model used here.

Assessing the association between supplemented puppyhood dietary fat sources and owner-reported epilepsy in adulthood, among Finnish companion dogs

Introduction

Epilepsy is a serious and common neurological condition in dogs, despite the wide number of antiepileptic drugs available, in approximately one third of the patients, epilepsy remains unsatisfactorily controlled. We aim to analyze whether feeding dietary fat sources during puppyhood was associated with canine epilepsy in adulthood.

Methods

A nested case-control study was compiled from the validated DogRisk food frequency questionnaire (DogRisk FFQ). DogRisk FFQ collected feeding, disease, and background data about the dog. The study sample consisted of 108 owner-reported epileptic cases and 397 non-epileptic controls. Each case was matched with up to four controls for the key confounding factors of sex, breed, and age. We analyzed associations between feeding as a puppy and owner-reported epilepsy as an adult dog using Cox regression. We tested 55 different food variables.

Results

We found that feeding fish fat from dietary sources at least once a week during puppyhood was inversely associated with epilepsy in later life in the unadjusted analysis [OR 0.46 (95% CI 0.25-0.83), p=0.01], while when adjusting for keeping conditions and dog characteristics the association was [OR 0.45 (95% CI 0.23-0.88), p=0.02]. When adjusted for keeping conditions, dog characteristics, and other feeding factors, the association was of similar magnitude but not significance [OR 0.56 (95% CI 0.27-1.15), p=0.12].

Discussion

The study indicates possible protective associations of feeding the dog with dietary sources of fish fat against epilepsy, although the result could be confounded by other feeding factors. Findings are compatible with current knowledge regarding the role of omega-3 fatty acids and ketogenic diet, a low carbohydrate, high fat diet as supportive treatments of epilepsy. As our findings are based on observations, we suggest the possibility of causality but do not prove it. Dietary intervention studies should now be conducted to confirm our findings.

The association between maternal diabetes and neonatal seizures: a nested case-Control study

Aim

We aimed to evaluate the association of pregestational diabetes mellitus (PGDM) and gestational diabetes mellitus (GDM) with neonatal seizures during neonatal hospitalization.

Methods

In this nested case-control study, all data were collected from the data files of the National Vital Statistics System (NVSS) 2016-2021. Considering the effect of confounders, we used the propensity-score matching (PSM; case:control = 1:4) method to select the study population. The outcome was considered the occurrence of neonatal seizures. Univariate and multivariate logistic regression analyses were adopted to assess the association of PGDM and GDM with neonatal seizures. We also conducted stratified analyses according to gestational age, birthweight, 5 min Apgar score, and maternal age to explore the potential disparities.

Results

After using the PSM method, a total of 6,674 cases of neonatal seizures and 26,696 controls were included. After adjusting for covariates, PGDM was associated with an increased risk of neonatal seizures [odds ratio (OR) = 1.51, 95% confidence interval (CI): 1.15-1.98], whereas the association between GDM and neonatal seizures is not statistically significant. In addition, the correlation between PGDM and increased risk of neonatal seizures was observed in neonates with a gestational age of 37-42 weeks and ≥42 weeks, with a 5 min Apgar score of ≥7, and with a maternal age of ≤40 years.

Conclusion

PGDM was found to be closely associated with an increased risk of neonatal seizures. The findings of our study indicated that neonatologists should consider monitoring the incidence of neonatal seizures in neonates born to mothers with PGDM.

The Swedish medical birth register during five decades: documentation of the content and quality of the register

Pregnancy-related factors are important for short- and long-term health in mothers and offspring. The nationwide population-based Swedish Medical Birth Register (MBR) was established in 1973. The present study describes the content and quality of the MBR, using original MBR data, Swedish-language and international publications based on the MBR.The MBR includes around 98% of all births in Sweden. From 1982 onwards, the MBR is based on prospectively recorded information in standardized antenatal, obstetric, and neonatal records. When the mother and infant are discharged from hospital, this information is forwarded to the MBR, which is updated annually. Maternal data include information from first antenatal visit on self-reported obstetric history, infertility, diseases, medication use, cohabitation status, smoking and snuff use, self-reported height and measured weight, allowing calculation of body mass index. Birth and neonatal data include date and time of birth, mode of delivery, singleton or multiple birth, gestational age, stillbirth, birth weight, birth length, head circumference, infant sex, Apgar scores, and maternal and infant diagnoses/procedures, including neonatal care. The overall quality of the MBR is very high, owing to the semi-automated data extraction from the standardized regional electronic health records, Sweden's universal access to antenatal care, and the possibility to compare mothers and offspring to the Total Population Register in order to identify missing records. Through the unique personal identity numbers of mothers and live-born offspring, the MBR can be linked to other health registers. The Swedish MBR contains high-quality pregnancy-related information on more than 5 million births during five decades.

Low Apgar score and asphyxia complications at birth and risk of longer-term cardiovascular disease: a nationwide population-based study of term infants

Background

Most follow-up studies have focused on the long-term consequences of asphyxia at birth on the brain. The aim of this study was to investigate associations between low Apgar score and asphyxia-related complications and subsequent risks of cardiovascular diseases (CVD) in childhood and early adulthood.

Methods

This population-based cohort study included 2,826,424 non-malformed singleton births, born at term (≥37 weeks' gestation) between 1988 and 2018 in Sweden. Primary exposure was a composite of asphyxia-related complications, defined as a) Apgar score 0-3 at 1-min; or b) Apgar score 0-3 at 5-min; or c) neonatal seizures (including hypoxic ischemic encephalopathy). Using Cox regression, we estimated the risk of CVD after 1 year of age, defined as stroke, coronary heart disease, heart failure, and atrial fibrillation.

Results

Overall, there were 4165 cases with cardiovascular diseases. Individuals with asphyxia-related complications had adjusted hazard ratios (95% confidence intervals) of 1.90 (1.54 to 2.34) for cardiovascular disease, 2.29 (1.74 to 3.03) for stroke, 2.17 (1.37 to 3.42) for heart failure, and 1.38 (0.87 to 2.17) for atrial fibrillation. Hazard ratios for CVD were elevated among individuals with Apgar score 0-3 at 1 and 5 min, and those with neonatal seizures. Compared with unexposed individuals, neonatal seizures were associated with 5 times higher rates of stroke and heart failure, respectively.

Interpretation

Asphyxia-related complications and its neonatal complications, especially low Apgar score and neonatal seizures, are associated with increased risks of CVD in childhood and early adulthood, although the absolute risk of CVD is low in young age.

Funding

Swedish Research Council and the Swedish Heart-Lung Foundation.

Increasing Pre-pregnancy Body Mass Index and Pregnancy Outcomes in the United States

INTRODUCTION

 As many Americans are becoming overweight or obese, increased body mass index (BMI) is fast becoming normalized. There is a need for more research that highlights the association between pre-pregnancy obesity and adverse pregnancy outcomes.

AIM

To determine the association between increasing pre-pregnancy BMI and adverse pregnancy outcomes.

METHODS

We utilized the United States Vital Statistics records to collate data on all childbirths in the United States between 2015 and 2019. We determined the association between increasing pre-pregnancy BMI and adverse pregnancy outcomes using multivariate analysis. Neonatal outcomes measures include the five-minute Apgar score, neonatal unit admission, neonates receiving assisted ventilation > six hours, neonatal antibiotics use, and neonatal seizures. Maternal outcomes include cesarean section rate, mothers requiring blood transfusion, unplanned hysterectomy, and intensive care unit admission. In addition, we controlled for maternal parameters such as race/ethnicity, age, insurance type, and pre-existing conditions such as chronic hypertension and prediabetes. Other covariates include paternal race, age and education level, gestational diabetes mellitus, induction of labor, weight gain during pregnancy, gestational age at delivery, and delivery weight.

RESULTS

We studied 15,627,572 deliveries in the US Vital Statistics records between 2015 and 2019. Among these women, 3.36% were underweight, 43.19% were with a normal BMI, 26.34% were overweight, 14.73% were in the obese class I, 7.23% were in the obese class II, and 5.14% were in the obese class III. Increasing pre-pregnancy BMI was associated with significant adverse outcomes across all measures of maternal and neonatal outcomes.

CONCLUSION

 A strong association exists between increasing pre-pregnancy BMI and adverse maternal and neonatal outcomes. The higher risk of adverse pregnancy outcomes among overweight and obese women remained even after controlling for other traditional risk factors of adverse maternal and neonatal outcomes.