Prenatal paracetamol exposure and child neurodevelopment: A review

Roles of Epigenetics and Glial Cells in Drug-Induced Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by severe deficits in social communication and interaction, repetitive movements, abnormal focusing on objects, or activity that can significantly affect the quality of life of the afflicted. Neuronal and glial cells have been implicated. It has a genetic component but can also be triggered by environmental factors or drugs. For example, prenatal exposure to valproic acid or acetaminophen, or ingestion of propionic acid, can increase the risk of ASD. Recently, epigenetic influences on ASD have come to the forefront of investigations on the etiology, prevention, and treatment of this disorder. Epigenetics refers to DNA modifications that alter gene expression without making any changes to the DNA sequence. Although an increasing number of pharmaceuticals and environmental chemicals are being implicated in the etiology of ASD, here, we specifically focus on the molecular influences of the abovementioned chemicals on epigenetic alterations in neuronal and glial cells and their potential connection to ASD. We conclude that a better understanding of these phenomena can lead to more effective interventions in ASD.

Inhibition of Adult Neurogenesis in Male Mice after Repeated Exposure to Paracetamol Overdose

Paracetamol, or acetaminophen (N-acetyl-para-aminophenol, APAP), is an analgesic and antipyretic drug that is commonly used worldwide, implicated in numerous intoxications due to overdose, and causes serious liver damage. APAP can cross the blood-brain barrier and affects brain function in numerous ways, including pain signals, temperature regulation, neuroimmune response, and emotional behavior; however, its effect on adult neurogenesis has not been thoroughly investigated. We analyze, in a mouse model of hepatotoxicity, the effect of APAP overdose (750 mg/kg/day) for 3 and 4 consecutive days and after the cessation of APAP administration for 6 and 15 days on cell proliferation and survival in two relevant neurogenic zones: the subgranular zone of the dentate gyrus and the hypothalamus. The involvement of liver damage (plasma transaminases), neuronal activity (c-Fos), and astroglia (glial fibrillar acidic protein, GFAP) were also evaluated. Our results indicated that repeated APAP overdoses are associated with the inhibition of adult neurogenesis in the context of elevated liver transaminase levels, neuronal hyperactivity, and astrogliosis. These effects were partially reversed after the cessation of APAP administration for 6 and 15 days. In conclusion, these results suggest that APAP overdose impairs adult neurogenesis in the hippocampus and hypothalamus, a fact that may contribute to the effects of APAP on brain function.

News in pharmacology for the main medical pathologies of gestation

Obstetric diseases represent a highly complex medical challenge, especially regarding its clinical approach. The use of pharmacological agents during pregnancy is one of the main therapeutic alternatives in this group of patients; however, there is a general lack of knowledge about its use, efficacy, and possible adverse effects that may occur in routine clinical practice, even among medical professionals themselves. The high percentage of pregnant women who undergo drugs at some point during pregnancy, together with the developments that have occurred in recent years in the field of pharmacology, show the need for a detailed analysis that shows the existing current knowledge and helps in the clinical decision making. In this sense, the aim of this work is to conduct a review of the available scientific literature on the novelties in pharmacology for the main medical pathologies of pregnancy. Thus, the role of this field in analgesia, antibiotic therapy, digestive, respiratory, urological, psychiatric and neurological pathologies will be detailed, evaluating the indications, precautions and considerations that must be taken into account for its use.

The relationship of prenatal acetaminophen exposure and attention-related behavior in early childhood

Acetaminophen is currently the only analgesic considered safe for use throughout pregnancy, but recent studies indicate that prenatal exposure to acetaminophen may be related to poorer neurodevelopmental outcomes. Multiple studies have suggested that it may be associated with attention problems, but few have examined this association by trimester of exposure. The Illinois Kids Development Study is a prospective birth cohort located in east-central Illinois. Exposure data were collected between December 2013 and March 2020, and 535 newborns were enrolled during that period. Mothers reported the number of times they took acetaminophen at six time points across pregnancy. When children were 2, 3, and 4 years of age, caregivers completed the Child Behavior Checklist for ages 1.5-5 years (CBCL). Associations of acetaminophen use during pregnancy with scores on the Attention Problems and ADHD Problems syndrome scales, the Internalizing and Externalizing Behavior composite scales, and the Total Problems score were evaluated. Higher acetaminophen exposure during the second trimester of fetal development was associated with higher Attention Problems, ADHD Problems, Externalizing Behavior, and Total Problems scores at ages 2 and 3. Higher second trimester exposure was only associated with higher Externalizing Behavior and Total Problems scores at 4 years. Higher cumulative exposure across pregnancy was associated with higher Attention Problems and ADHD Problems scores at ages 2 and 3. Findings suggest that prenatal acetaminophen exposure, especially during the second trimester, may be related to problems with attention in early childhood.

Examining the relationship of acetaminophen use during pregnancy with early language development in children

BACKGROUND

Acetaminophen is the only analgesic considered safe for use throughout pregnancy. Recent studies suggest that use during pregnancy may be associated with poorer neurodevelopmental outcomes in children, but few have examined language development.

METHODS

The Illinois Kids Development Study is a prospective birth cohort in east-central Illinois. Between December 2013 and March 2020, 532 newborns were enrolled and had exposure data available. Participants reported the number of times they took acetaminophen six times across pregnancy. Language data were collected at 26.5-28.5 months using the MacArthur-Bates Communicative Development Inventories (CDI; n = 298), and 36-38 months using the Speech and Language Assessment Scale (SLAS; n = 254).

RESULTS

Taking more acetaminophen during the second or third trimester was associated with marginally smaller vocabularies and shorter utterance length (M3L) at 26.5-28.5 months. More acetaminophen use during the third trimester was also associated with increased odds of M3L scores ≤25th percentile in male children. More use during the second or third trimester was associated with lower SLAS scores at 36-38 months. Third trimester use was specifically related to lower SLAS scores in male children.

CONCLUSIONS

Higher prenatal acetaminophen use during pregnancy may be associated with poorer early language development.

IMPACT

Taking more acetaminophen during pregnancy, particularly during the second and third trimesters, was associated with poorer scores on measures of language development when children were 26.5-28.5 and 36-38 months of age. Only male children had lower scores in analyses stratified by child sex. To our knowledge, this is the first study that has used a standardized measure of language development to assess the potential impact of prenatal exposure to acetaminophen on language development. This study adds to the growing body of literature suggesting that the potential impact of acetaminophen use during pregnancy on fetal neurodevelopment should be carefully evaluated.

Postnatal acetaminophen exposure and neurodevelopmental outcomes at 18-21 months corrected gestational age in preterm infants <29 weeks gestation: a retrospective cohort study

BACKGROUND

Studies have reported prenatal acetaminophen exposure is associated with abnormal neurodevelopment. There is limited and conflicting data on neurodevelopmental outcomes following postnatal acetaminophen exposure. Our objective was to investigate the neurodevelopmental outcomes of preterm infants < 29 weeks gestation postnatally exposed to acetaminophen.

METHODS

Retrospective cohort study of infants born between 2008 and 2017 at a tertiary care perinatal center. Exclusion criteria included chromosomal disorders, major congenital abnormalities, and congenital infections. The primary outcome was a composite score of <85 on the cognitive, language, or motor components of the Bayley Scales of Infant and Toddler Development, 3rd edition, assessed at 18 to 21 months corrected gestational age. Multivariate logistic regression was used to assess confounders.

RESULTS

Of the 945 infants included in the study, 120 were in the acetaminophen group. There was no difference in any of Bayley-III cognitive, language or motor composite scores of < 85 between the two groups for postnatal acetaminophen exposure, adjusted odds ratios (aORs) 1.03, 95% CI 0.60-1.78, or days of acetaminophen use, aORs 1.10, 95% CI 0.93-1.29.

CONCLUSIONS

There was no difference in neurodevelopmental outcome between the acetaminophen exposed and non-exposed groups. Our results need validation in larger cohorts.

IMPACT

Animal research and cohort studies have suggested that prenatal acetaminophen exposure may be associated with an elevated risk of neurobehavioral abnormalities. However, there is limited and conflicting research on the impact of postnatal acetaminophen on neurodevelopment. The results of this study suggest that postnatal acetaminophen does not negatively impact neurodevelopment at 18 to 21 months in preterm infants born at <29 weeks gestational age. While these results need validation in larger and more longitudinal studies, this study provides reassurance for the use of postnatal acetaminophen in extremely preterm infants.

Impact of Prenatal Acetaminophen Exposure for Hippocampal Development Disorder on Mice

Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used as analgesic agents. They have been detected in various environmental matrices. The degradation of environmental contaminants and the long-term adverse effects have become a major public concern. Prenatal exposure to acetaminophen can cause damage to the developing hippocampus. However, the molecular mechanisms behind hippocampal damage following prenatal acetaminophen exposure (PAcE) remain unclear. The present study shows an increased risk of adverse neurodevelopmental outcomes in offspring following exposure to acetaminophen during pregnancy on mice. The results revealed that different doses, timings, and duration of exposure to acetaminophen during pregnancy were associated with dose-dependent changes in the hippocampus of the offspring. Furthermore, exposure to high doses, multiple-treatment courses, and late pregnancy induced pathological changes, such as wrinkling and vacuolation, inhibited hippocampal proliferation and increased apoptosis. In addition, PAcE significantly decreased the expression of genes related to synaptic development in fetal hippocampal neurons and hippocampal astrocyte and microglia were also damaged to varying degrees. The significant reduction either in SOX2, an essential gene in regulating neural progenitor cell proliferation, and reduction of genes related to the SOX2/Notch pathway may suggest that the role of SOX2/Notch pathway in impaired hippocampal development in the offspring due to PAcE. In general, PAcE at high doses, multiple-treatment courses, and mid- and late gestation were associated with neurodevelopmental toxicity to the offspring.

Early neurodevelopmental outcomes of extreme preterm infants exposed to paracetamol: a retrospective cohort study

BACKGROUND

Paracetamol is commonly used for analgesia and patent ductus arteriosus (PDA) treatment in preterm infants. We aimed to evaluate early neurodevelopmental outcomes of extreme preterm infants exposed to paracetamol during their neonatal admission.

METHODS

This retrospective cohort study included surviving infants born at <29 weeks gestation, or with a birth weight of <1000 grams. Neurodevelopmental outcomes studied were early cerebral palsy (CP) or high risk of CP diagnosis, Hammersmith Infant Neurological Examination (HINE) score and Prechtl General Movement Assessment (GMA) at 3-4 months corrected age.

RESULTS

Two hundred and forty-two infants were included, of which 123 were exposed to paracetamol. After adjusting for birth weight, sex and chronic lung disease, there were no significant associations between paracetamol exposure and early CP or high risk of CP diagnosis (aOR 1.46, 95% CI 0.61, 3.5), abnormal or absent GMA (aOR 0.82, 95% CI 0.37, 1.79) or HINE score (adjusted β -0.19, 95% CI -2.39, 2.01). Subgroup analysis stratifying paracetamol exposure into <180 mg/kg or ≥180 mg/kg cumulative dose found that neither had significant effects on outcomes.

CONCLUSIONS

In this cohort of extreme preterm infants, no significant association was found between exposure to paracetamol during the neonatal admission and adverse early neurodevelopment.

IMPACT

Paracetamol is commonly used in the neonatal period for analgesia and patent ductus arteriosus treatment in preterm infants, although prenatal paracetamol use has been associated with adverse neurodevelopmental outcomes. Exposure to paracetamol during the neonatal admission was not associated with adverse early neurodevelopment at 3-4 months corrected age in this cohort of extreme preterm infants. The findings from this observational study is consistent with the small body of literature supporting the lack of association between neonatal paracetamol exposure and adverse neurodevelopmental outcomes in preterm infants.

Gestational paracetamol exposure induces core behaviors of neurodevelopmental disorders in infant rats and modifies response to a cannabinoid agonist in females

Paracetamol (PAR) is an over-the-counter analgesic/antipyretic used during pregnancy worldwide. Epidemiological studies have been associating gestational PAR exposure with neurobehavioral alterations in the progeny resembling autism spectrum disorders and attention-deficit hyperactivity disorder symptoms. The endocannabinoid (eCB) dysfunction was previously hypothesized as one of the modes of action by which PAR may harm the developing nervous system. We aimed to evaluate possible effects of gestational exposure to PAR on male and female rat's offspring behavior and if an acute injection of WIN 55,212-2 (WIN, 0.3 mg/kg), a non-specific cannabinoid agonist, prior to behavioral tests, would induce different effects in PAR exposed and non-exposed animals. Pregnant Wistar rats were gavaged with PAR (350 mg/kg/day) or water from gestational day 6 until delivery. Nest-seeking, open field, apomorphine-induced stereotypy, marble burying and three-chamber tests were conducted in 10-, 24-, 25- or 30-days-old rats, respectively. PAR exposure resulted in increased apomorphine-induced stereotyped behavior and time spent in the central area of the open field in exposed female pups. Additionally, it induced hyperactivity in the open field and increased marble burying behavior in both male and female pups. WIN injection modified the behavioral response only in the nest seeking test, and opposite effects were observed in control and PAR-exposed neonate females. Reported alterations are relevant for the neurodevelopmental disorders that have been associated with maternal PAR exposure and suggest that eCB dysfunction may play a role in the action by which PAR may harm the developing brain.

Paracetamol use in pregnancy: Not as safe as we may think?

Paracetamol is used by more than 50% of women worldwide during pregnancy; headache representing the most frequent indication. Several studies report that long-term exposure to paracetamol in utero is associated with adverse neurodevelopmental outcomes in children, indicating a dose-response effect. However, less or no risk is found to be associated with short-term exposure. Paracetamol most likely crosses the placenta through passive diffusion, and there are several possible mechanisms for how paracetamol might affect fetal brain development. Although the literature suggests an association between prenatal paracetamol exposure and neurodevelopmental outcomes, the role of confounders cannot be ruled out. Consequently, as a precaution, we believe that pregnant women should be recommended ideally to only use paracetamol to treat conditions that might harm the fetus, such as severe pain or a high fever. This Comment aims to put focus on the potential fetal risks of paracetamol exposure in utero.

In utero acetaminophen exposure and child neurodevelopmental outcomes: Systematic review and meta-analysis

BACKGROUND

Acetaminophen is a frequently used analgesic for pain and fever. There have been reports of adverse neurodevelopmental outcomes associated with in utero acetaminophen exposure. However, it is unclear whether this association is related directly to acetaminophen use, or the reasons for use.

OBJECTIVES

To summarise the literature on the association between in utero acetaminophen exposure and child neurodevelopmental outcomes, and assess the extent to which the association is due to confounding by indication.

DATA SOURCES

OVID for Medline, Embase, and PsycINFO, and EBSCO for CINAHL, from inception to August 18, 2022.

STUDY SELECTION AND DATA EXTRACTION

We searched for peer-reviewed, English-language studies on in utero acetaminophen exposure and child neurodevelopmental outcomes. Data were extracted using a standardised form created a priori, and quality was assessed using the Systematic Assessment of Quality in Observational Research.

SYNTHESIS

We generated pooled risk ratios (RR) for outcomes examined by ≥3 studies using random-effects models; outcomes that could not be meta-analysed were narratively summarised following Synthesis Without Meta-Analysis guidelines.

RESULTS

Twenty-two studies including 23 cohorts were eligible (n = 367,775 total participants; median: 51.7% with acetaminophen exposure). Studies were primarily prospective cohort studies from Europe and the US, with attention deficit/hyperactivity disorder (ADHD) being the most common outcome. Quality assessments resulted in 13.6% of studies being classified as high, 59.1% as medium, 22.7% as low, and 4.5% as very low quality. In utero acetaminophen exposure was associated with an elevated risk of ADHD (unadjusted pooled RR 1.32, 95% confidence interval [CI] 1.20, 1.44; I²  = 47%, n = 7 studies), with little difference after adjusting for confounders, including indications for acetaminophen use (adjusted pooled RR 1.34, 95% CI 1.15, 1.55; I²  = 50%, n = 4 studies).

CONCLUSIONS

Confounding by indication did not explain the association between in utero acetaminophen exposure and child ADHD. Further, high-quality research is needed on this and other neurodevelopmental outcomes.

Safety of drugs used for the treatment of migraine during pregnancy: a narrative review

INTRODUCTION

Migraine is common in females of childbearing age and negatively impacts quality of life. The majority of those with migraine who become pregnant see an improvement in their condition but not all do. Providing evidence-based recommendations for the pharmacological management of migraine in pregnancy is challenging.

AREAS COVERED

This narrative review provides an update on the safety of drugs used for migraine in pregnancy. National and international guidelines on the management of episodic migraine in adults were used to select the drugs of relevance to pregnant women. The final list of drugs was chosen by a pain specialist who categorized them according to drug class and use in acute management or prevention. PubMed was searched from inception to 31st July 2022 for evidence on drug safety.

EXPERT OPINION

Obtaining high-quality drug safety data in pregnant migraineurs is difficult not least because exposing a fetus to research-related risks is often considered unethical. There is reliance on observational studies which often group drugs together and lack specificities pertinent to drug prescribing like timing, dosing and duration. Improved statistical tools, study designs and the creation of international collaborative frameworks are ways to advance knowledge on drug safety in pregnancy.

Prenatal exposure to acetaminophen and adolescent assessment of behavior: Discrepancies by age and reporter

Acetaminophen, which is one of the most commonly used medications during pregnancy, has been linked to adverse neurodevelopmental outcomes among offspring during childhood. Less is known about associations with outcomes occurring later in adolescence. Methods: We conducted a follow-up study of children born between 1996 and 2002. Data on illnesses and medications, including acetaminophen, during pregnancy were collected through a standardized interview after delivery. Behavioral assessments were conducted at two subsequent time points, childhood (ages 5-10) and adolescence (ages 11-17). Outcomes examined included internalizing, externalizing, and total behavior problems based on the parent-completed Child Behavior Checklist (CBCL), the teacher-completed Teacher Report Form (TRF), and the youth-completed Youth Self Report (YSR, adolescent follow-up only). Adjusted linear regression models were used to calculate mean differences (MD) and 95% confidence intervals (95% CI) in T-scores comparing those with prenatal acetaminophen exposure to those without. Stabilized inverse probability weights were used to account for attrition. Results: Among the 216 mother-child dyads with completed parent and teacher behavioral assessments at both childhood and adolescence, prenatal acetaminophen exposure was not associated with behavioral problems according to either parent or teacher assessments. Modest increases in externalizing and total behavior problems were observed according to youth report (MD: 1.9). Compared to associations observed during the childhood follow-up, associations at adolescence were attenuated according to parent-report. Conclusion: Reported associations between prenatal acetaminophen exposure and behavioral outcomes were not consistent over time nor between reporters.

Analysis of umbilical cord tissue as an indicator of in utero exposure to toxic adulterating substances

In utero drug exposure is a significant public health threat to the well-being and normal development of the neonate. Recently, testing of umbilical cord tissue (UCT) has been employed to measure illicit drug exposure, as drugs used by the mother during the third trimester may be retained in the UCT. Focus has also been given to potential adverse health effects among drug users, resulting from exposure to pharmacologically active adulterants and cutting agents in the street drug supply. The in utero effects of these substances have not been well studied in humans, nor has their presence been demonstrated as a means for assessing adverse health effects in the neonate. Here, we describe the application of a novel test method to analyze UCT for the presence of more than 20 common adulterating/cutting substances via LC/Q-TOF. In total, 300 de-identified UCT samples were analyzed-all had previously tested positive for cocaine or opiates. Generally, the positivity rates of individual compounds were similar between the Cocaine and Opiates Subgroups, apart from levamisole, xylazine, dipyrone (metabolites), and promethazine. Many of the adulterants used in the street drug supply do have legitimate medicinal/therapeutic uses, including several of the compounds most frequently detected in this study. Caffeine and lidocaine were the most frequently identified compounds both individually (>70% each) and in combination with each other. Alternatively, levamisole, an adulterant with no legitimate therapeutic use, was present in 12% of cases. Importantly, this data demonstrates that the detection of traditional drugs of abuse may serve as indicators of potential in utero exposure to toxic adulterating substances during gestation. While there is cause for concern with respect to any unintentional drug exposure, illicit drug use during pregnancy, including uncontrolled dosing, poly-adulterant consumption, and the interactions of these drug mixtures, produces a significant public health threat to the neonate which warrants further study.

Paracetamol (acetaminophen) for patent ductus arteriosus in preterm or low birth weight infants

BACKGROUND

The different management strategies for patent ductus arteriosus (PDA) in preterm infants are expectant management, surgery, or medical treatment with non-selective cyclo-oxygenase inhibitors. Randomized controlled trials (RCTs) have suggested that paracetamol may be an effective and safe agent for the closure of a PDA.

OBJECTIVES

To determine the efficacy and safety of paracetamol as monotherapy or as part of combination therapy via any route of administration, compared with placebo, no intervention, or another prostaglandin inhibitor, for prophylaxis or treatment of an echocardiographically-diagnosed PDA in preterm or low birth weight infants.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, and three trials registers on 13 October 2021, and one other database on 1 March 2022. We also checked references and contacted study authors to identify additional studies.

SELECTION CRITERIA

We included RCTs and quasi-RCTs in which paracetamol (single-agent or combination therapy) was compared to no intervention, placebo, or other agents used for closure of PDA, irrespective of dose, duration, and mode of administration in preterm infants. Two independent authors reviewed the search results and made a final selection of potentially eligible articles through discussion.

DATA COLLECTION AND ANALYSIS

We performed data collection and analyses in accordance with the methods of Cochrane Neonatal. We used the GRADE approach to assess the certainty of evidence for the following outcomes: failure of ductal closure after the first course of treatment; all-cause mortality during initial hospital stay; and necrotizing enterocolitis (NEC).

MAIN RESULTS

For this update, we included 27 studies enrolling 2278 infants. We considered the overall risk of bias in the 27 studies to vary from low to unclear. We identified 24 ongoing studies. Paracetamol versus ibuprofen  There was probably little to no difference between paracetamol and ibuprofen for failure of ductal closure after the first course (risk ratio (RR) 1.02, 95% confidence interval (CI) 0.88 to 1.18; 18 studies, 1535 infants; moderate-certainty evidence). There was likely little to no difference between paracetamol and ibuprofen for all-cause mortality during hospital stay (RR 1.09, 95% CI 0.80 to 1.48; 8 studies, 734 infants; moderate-certainty evidence), and for NEC (RR 1.30, 95% CI 0.87 to 1.94; 10 studies, 1015 infants; moderate-certainty evidence). Paracetamol versus indomethacin There was little to no difference between paracetamol and indomethacin for failure of ductal closure after the first course (RR 1.02, 95% CI 0.78 to 1.33; 4 studies, 380 infants; low-certainty evidence). There was little to no difference between paracetamol and indomethacin for all-cause mortality during hospital stay (RR 0.86, 95% CI 0.39 to 1.92; 2 studies, 114 infants; low-certainty evidence). The rate of NEC may be lower in the paracetamol group (3.7%) versus the indomethacin group(9.2%) (RR 0.42, 95% CI 0.19 to 0.96; 4 studies, 384 infants; low-certainty evidence).  Prophylactic paracetamol versus placebo/no intervention Prophylactic paracetamol (17%) compared to placebo/no intervention (61%) may reduce failure of ductal closure after one course (RR 0.27, 95% CI 0.18 to 0.42; 3 studies, 240 infants; low-certainty evidence). There was little to no difference between prophylactic paracetamol and placebo/no intervention for all-cause mortality during hospital stay (RR 0.59, 95% CI 0.24 to 1.44; 3 studies, 240 infants; low-certainty evidence). No studies reported on NEC.  Early paracetamol treatment versus placebo/no intervention Early paracetamol treatment (28%) compared to placebo/no intervention (79%) may reduce failure of ductal closure after one course when used before 14 days' postnatal age (RR 0.35, 95% CI 0.23 to 0.53; 2 studies, 127 infants; low-certainty evidence). No studies reported on all-cause mortality during hospital stay or NEC.  Late paracetamol treatment versus placebo/no intervention  There was little to no difference between late paracetamol and placebo for failure of ductal closure after one course of treatment when used at or after 14 days' postnatal age (RR 0.85, 95% CI 0.72 to 1.01; 1 study, 55 infants; low-certainty evidence) or NEC (RR 1.04, 95% CI 0.07 to 15.76; 1 study, 55 infants; low-certainty evidence). No data were reported for all-cause mortality during hospital stay.  Paracetamol combined with ibuprofen versus ibuprofen combined with placebo or no intervention There was little to no difference between paracetamol plus ibuprofen compared to ibuprofen plus placebo or no intervention for failure of ductal closure after the first course (RR 0.77, 95% CI 0.43 to 1.36; 2 studies, 111 infants; low-certainty evidence). There was little to no difference between paracetamol plus ibuprofen compared to ibuprofen plus placebo or no intervention for NEC (RR 0.33, 95% CI 0.01 to 7.45; 1 study, 24 infants; low-certainty evidence). No data were reported for all-cause mortality during hospital stay.  AUTHORS' CONCLUSIONS: Moderate-certainty evidence suggests that there is probably little or no difference in effectiveness between paracetamol and ibuprofen; low-certainty evidence suggests that there is probably little or no difference in effectiveness between paracetamol and indomethacin; low-certainty evidence suggests that prophylactic paracetamol may be more effective than placebo/no intervention; low-certainty evidence suggests that early paracetamol treatment may be more effective than placebo/no intervention; low-certainty evidence suggests that there is probably little or no difference between late paracetamol treatment and placebo, and probably little or no difference in effectiveness between the combination of paracetamol plus ibuprofen versus ibuprofen alone for the closure of PDA after the first course of treatment. The majority of neonates included in these studies were of moderate preterm gestation. Thus, establishing the efficacy and safety of paracetamol for PDA treatment in extremely low birth weight (ELBW: birth weight < 1000 grams) and extremely low gestational age neonates (ELGANs < 28 weeks' gestation) requires further studies.

Dual medication therapy (acetaminophen and ibuprofen) for the management of patent ductus arteriosus in preterm infants: a systematic review and meta-analysis

OBJECTIVE

To examine the efficacy of dual medication therapy (intervention) (DMT: acetaminophen and ibuprofen) vs. single medication therapy (control) (SMT: ibuprofen) for medical management of PDA (outcomes) in preterm infants (population).

STUDY DESIGN

We systematically searched multiple sources to identify randomized controlled trials (RCT) and non-randomized studies (NRS) that compared DMT to SMT for management of hemodynamically significant PDA.

RESULTS

We identified two RCTs and four NRS. There were no differences in the rates of successful PDA closure following the first treatment course between DMT and SMT (RR = 1.23 [95% CI 0.89-1.70] for NRS and RR = 1.18 [95% CI 0.66-2.10] for RCTs), nor were there significant differences in secondary outcomes and adverse events including PDA ligation, bronchopulmonary dysplasia, and necrotizing enterocolitis etc. Markers of hepatic/renal function did not change significantly during treatment.

CONCLUSION

We found no evidence for superiority of DMT over SMT in PDA management.

The use of paracetamol during pregnancy: A qualitative study and possible strategies for a clinical trial

Paracetamol (N-acetyl-p-aminophenol (APAP), also known as acetaminophen) is used to relieve mild to moderate pain and reduce fever. APAP is widely used during pregnancy as it is considered safe when used as directed by regulatory authorities. However, a significant amount of epidemiological and experimental research suggests that prenatal exposure potentially alters fetal development. In this paper, we summarize the potentially harmful adverse effects of APAP and the limitations of the current evidence. It highlights the urgent need for a clinical trial, and the aim of the presented qualitative pilot study on APAP use during pregnancy is the feasibility of a large-scale randomized controlled trial (RCT). In the qualitative study, we included 232 Danish women from three hospitals in the spring of 2021. After recognizing the pregnancy, 48% had taken any APAP, and 6% had taken it weekly or more than weekly. A total of 27% who had taken APAP in the first trimester of pregnancy (even rarely) would potentially participate in an RCT. In a potential clinical trial, the women would need to be included early in the 1st trimester as the suspected harmful effects of APAP lies within this early reproductive developmental window. A possible recruitment strategy was explored. These data suggest that the target population appears positive towards an RCT. As a negative attitude among users has been considered the major hindrance for such a study, we cannot see hindrances for performing an RCT.

Interleukin-1β-induced inflammation and acetaminophen during infancy: Distinct and interactive effects on social-emotional and repetitive behavior in C57BL/6J mice

Acetaminophen (APAP) exposure early in life has been associated with increased risk of neurodevelopmental disorders in epidemiological studies. In rodent models, early-life APAP has similarly been shown to produce long-term changes in brain and behavior, including altered activity levels and social behavior. Most rodent studies to date have, nevertheless, attempted to model early-life APAP without considering that most APAP exposure occurs in a context of immune activation and/or fever. To mimic the repeated infections common during infancy, we employed the cytokine interleukin-1β (IL-1β) to induce immune activation three times during early postnatal development (i.e., day 5, 8, and 11). On these days, C57BL/6J pups were administered either IL-1β (0.2 μg/kg) or saline vehicle followed, after 45 min, by either APAP (103.9 mg/kg) or vehicle. Mice were subsequently administered a battery of tests of social-emotional and repetitive behavior. A number of distinct long-term effects of IL-1β and APAP treatments were found, including sex-specific shifts in repetitive behavior and emotional hyperthermia following early-life IL-1β and increased social caution in males following early-life APAP. We also observed significant interaction between IL-1β and APAP: as adults, 'two-hit' IL-1β + APAP females displayed greater anxiety-related thigmotaxis across a number of tests, including an open field. 'Two hit' males, in turn, showed elevated levels of avoidance of an unfamiliar social partner during a social interaction test. Our results highlight that IL-1β-induced inflammation and APAP have both distinct effects and significant interactions during early life, with enduring sex-specific effects on phenotypes relevant to neurodevelopmental disorders.

In Utero Exposure to Caffeine and Acetaminophen, the Gut Microbiome, and Neurodevelopmental Outcomes: A Prospective Birth Cohort Study

Pregnant individuals are exposed to acetaminophen and caffeine, but it is unknown how these exposures interact with the developing gut microbiome. We aimed to determine whether acetaminophen and/or caffeine relate to the childhood gut microbiome and whether features of the gut microbiome alter the relationship between acetaminophen/caffeine and neurodevelopment. Forty-nine and 85 participants provided meconium and stool samples at 6-7, respectively, for exposure and microbiome assessment. Fecal acetaminophen and caffeine concentrations were quantified, and fecal DNA underwent metagenomic sequencing. Caregivers and study staff assessed the participants' motor and cognitive development using standardized scales. Prenatal exposures had stronger associations with the childhood microbiome than concurrent exposures. Prenatal acetaminophen exposure was associated with a trend of lower gut bacterial diversity in childhood [β = -0.17 Shannon Index, 95% CI: (-0.31, -0.04)] and was marginally associated with differences in the relative abundances of features of the gut microbiome at the phylum (Firmicutes, Actinobacteria) and gene pathway levels. Among the participants with a higher relative abundance of Proteobacteria, prenatal exposure to acetaminophen and caffeine was associated with lower scores on WISC-IV subscales. Acetaminophen during bacterial colonization of the naïve gut is associated with lasting alterations in childhood microbiome composition. Future studies may inform our understanding of downstream health effects.

Low reliability of DNA methylation across Illumina Infinium platforms in cord blood: implications for replication studies and meta-analyses of prenatal exposures

Background

There is an increasing interest in the role of epigenetics in epidemiology, but the emerging research field faces several critical biological and technical challenges. In particular, recent studies have shown poor correlation of measured DNA methylation (DNAm) levels within and across Illumina Infinium platforms in various tissues. In this study, we have investigated concordance between 450 k and EPIC Infinium platforms in cord blood. We could not replicate our previous findings on the association of prenatal paracetamol exposure with cord blood DNAm, which prompted an investigation of cross-platform DNAm differences.

Results

This study is based on two DNAm data sets from cord blood samples selected from the Norwegian Mother, Father and Child Cohort Study (MoBa). DNAm of one data set was measured using the 450 k platform and the other data set was measured using the EPIC platform. Initial analyses of the EPIC data could not replicate any of our previous significant findings in the 450 k data on associations between prenatal paracetamol exposure and cord blood DNAm. A subset of the samples (n = 17) was included in both data sets, which enabled analyses of technical sources potentially contributing to the negative replication. Analyses of these 17 samples with repeated measurements revealed high per-sample correlations (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\stackrel{\mathrm{-}}{\text{R}}\hspace{0.17em}\approx$$\end{document}R-≈ 0.99), but low per-CpG correlations (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\stackrel{\mathrm{-}}{\text{R}}$$\end{document}R- ≈ 0.24) between the platforms. 1.7% of the CpGs exhibited a mean DNAm difference across platforms > 0.1. Furthermore, only 26.7% of the CpGs exhibited a moderate or better cross-platform reliability (intra-class correlation coefficient ≥ 0.5).

Conclusion

The observations of low cross-platform probe correlation and reliability corroborate previous reports in other tissues. Our study cannot determine the origin of the differences between platforms. Nevertheless, it emulates the setting in studies using data from multiple Infinium platforms, often analysed several years apart. Therefore, the findings may have important implications for future epigenome-wide association studies (EWASs), in replication, meta-analyses and longitudinal studies. Cognisance and transparency of the challenges related to cross-platform studies may enhance the interpretation, replicability and validity of EWAS results both in cord blood and other tissues, ultimately improving the clinical relevance of epigenetic epidemiology.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13148-022-01299-3.

Are Brain and Cognitive Reserve Shaped by Early Life Circumstances?

When growing older, many people are faced with cognitive deterioration, which may even amount to a form of dementia at some point in time. Although neuropathological signs of dementia disorders can often be demonstrated in brains of patients, the degree to which clinical symptoms are present does mostly not accurately reflect the amount of neuropathology that is present. Sometimes existent pathology even goes without any obvious clinical presentation. An explanation for this phenomenon may be found in the concept of reserve capacity. Reserve capacity refers to the ability of the brain to effectively buffer changes that are associated with normal aging processes and to cope with pathological damage. A larger reserve capacity has been suggested to increase resilience against age-associated cognitive deterioration and dementia disorders. Traditionally, a division has been made between brain reserve, which is based on morphological characteristics of the brain, and cognitive reserve, which is based on functional characteristics of the brain. The present review discusses the premises that brain and cognitive reserve capacity are shaped by prenatal and early postnatal factors. Evidence is accumulating that circumstances during the first 1,000 days of life are of the utmost importance for the lifelong health of an individual. Cognitive deterioration and dementia disorders may also have their origin in early life and a potentially important pathway by which the early environment affects the risk for neurodegenerative diseases is by developmental programming of the reserve capacity of the brain. The basic idea behind developmental programming of brain and cognitive reserve is explained and an overview of studies that support this idea is presented. The review is concluded by a discussion of potential mechanisms, synthesis of the evidence and relevance and future directions in the field of developmental origins of reserve capacity.

Analgesic drug use in pregnancy and neurodevelopment outcomes: an umbrella review

Emerging evidence from reviews suggests that analgesic drug exposure during pregnancy may contribute to child neurodevelopment outcomes. A comprehensive overview of existing evidence is needed for firm conclusions to inform clinical guidelines. This umbrella review aims to synthesise high-quality evidence on prenatal analgesic drug exposure and risk of ASD and ADHD in children. Seven databases were searched from inception to May 2021 to identify relevant reviews of any design. The AMSTAR 2 and the GRADE quality assessments were used to evaluate risk of bias and heterogeneity. A narrative synthesis approach was used to summarise findings. Five systematic reviews and meta-analyses met the inclusion criteria. All reviews reported significant associations between maternal prenatal acetaminophen use and ADHD outcomes (risk ratio range: 1.08-1.34; no pooled incidence rate), with a potential dose-dependent relationship. Potential sources of heterogeneity included usage timing and dosage. Findings suggest minimisation of prenatal acetaminophen exposure due to risk for ADHD outcomes. Future studies should include assessing potentially interacting mechanisms associating acetaminophen use with future neurodevelopmental outcomes.

Different approaches for patent ductus arteriosus in premature infants using acetaminophen

BACKGROUND

Acetaminophen use for pharmacological treatment of hemodynamically significant patent ductus arteriosus (hsPDA) in preterm infants is becoming more popular with emerging evidence that it is effective as well as safe alternative for other agents used to close hsPDA.

DATA SOURCES

We performed a narrative review of literature about pharmacological treatment of PDA using acetaminophen.

RESULTS

Acetaminophen was used as a prophylaxis, symptomatic, targeted, and a rescue approach.

CONCLUSIONS

It appears that acetaminophen could be used in different approaches to close the hsPDA. Long-term outcomes of acetaminophen exposure early in life still lack certainty.

Paracetamol (Acetaminophen) and its Effect on the Developing Mouse Brain

Paracetamol, or acetaminophen (AAP), is the most commonly used analgesic during pregnancy and early life. While therapeutic doses of AAP are considered harmless during these periods, recent findings in both humans and rodents suggest a link between developmental exposure to AAP and behavioral consequences later in life. The aim of this study is to evaluate the impact of neonatal exposure to clinically relevant doses of AAP on adult spontaneous behavior, habituation, memory, learning, and cognitive flexibility later in life using a mouse model. Markers of oxidative stress, axon outgrowth, and glutamatergic transmission were also investigated in the hippocampus during the first 24 h after exposure. In addition, potential long-term effects on synaptic density in the hippocampus have been investigated. In a home cage setting, mice neonatally exposed to AAP (30 + 30 mg/kg, 4 h apart) on postnatal day 10 displayed altered spontaneous behavior and changed habituation patterns later in life compared to controls. These mice also displayed reduced memory, learning and cognitive flexibility compared to control animals in the Morris water maze. An increase of markers for oxidative stress was observed in the hippocampus 6 h after AAP exposure. As AAP is the first choice treatment for pain and/or fever during pregnancy and early life, these results may be of great importance for risk assessment. Here we show that AAP can have persistent negative effects on brain development and suggest that AAP, despite the relatively low doses, is capable to induce acute oxidative stress in the hippocampus.

Childhood seizures after prenatal exposure to maternal influenza infection: a population-based cohort study from Norway, Australia and Canada

OBJECTIVE

To assess whether clinical and/or laboratory-confirmed diagnosis of maternal influenza during pregnancy increases the risk of seizures in early childhood.

DESIGN

Analysis of prospectively collected registry data for children born between 2009 and 2013 in three high-income countries. We used Cox regression to estimate country-level adjusted HRs (aHRs); fixed-effects meta-analyses were used to pool adjusted estimates.

SETTING

Population-based.

PARTICIPANTS

1 360 629 children born between 1 January 2009 and 31 December 2013 in Norway, Australia (New South Wales) and Canada (Ontario).

EXPOSURE

Clinical and/or laboratory-confirmed diagnosis of maternal influenza infection during pregnancy.

MAIN OUTCOME MEASURES

We extracted data on recorded seizure diagnosis in secondary/specialist healthcare between birth and up to 7 years of age; additional analyses were performed for the specific seizure outcomes 'epilepsy' and 'febrile seizures'.

RESULTS

Among 1 360 629 children in the study population, 14 280 (1.0%) were exposed to maternal influenza in utero. Exposed children were at increased risk of seizures (aHR 1.17, 95% CI 1.07 to 1.28), and also febrile seizures (aHR 1.20, 95% CI 1.07 to 1.34). There was no strong evidence of an increased risk of epilepsy (aHR 1.07, 95% CI 0.81 to 1.41). Risk estimates for seizures were higher after influenza infection during the second and third trimester than for first trimester.

CONCLUSIONS

In this large international study, prenatal exposure to influenza infection was associated with increased risk of childhood seizures.

Prophylactic Low-Dose Paracetamol Administration for Ductal Closure and Microstructural Brain Development in Preterm Infants

INTRODUCTION

Prophylactic low-dose paracetamol administration is used to induce closure of the ductus arteriosus. Effects on the neurological outcome in preterm infants remain unknown. We compared microstructural brain development in very preterm infants with and without exposure to prophylactic paracetamol by using MR-based diffusion tensor imaging.

MATERIALS AND METHODS

Infants aged <32 gestational weeks born between October 2014 and December 2018 received prophylactic paracetamol (10 mg/kg intravenously every 8 h until echocardiography after at least 72 h) and form the paracetamol group; infants born between February 2011 and September 2014 form the control group. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) at term-equivalent age were measured in 14 defined cerebral regions and compared between the groups.

RESULTS

Included in the study were 340 infants, of whom 217 received prophylactic paracetamol, and 123 formed the control group. The paracetamol group showed significantly higher FA values and lower ADC values in the splenium of the corpus callosum, as well as higher FA values in the pons bilaterally, the left middle cerebellar peduncle, the right occipital white matter, and the right posterior limb of the internal capsule (p ≤ 0.02).

CONCLUSION

The perceived safety of prenatal paracetamol exposure has been questioned in recent years. We found no impairment on microstructural maturation processes in the brain of preterm infants at term-equivalent age following early paracetamol administration. The clinical relevance of these imaging findings has to be determined in long-term follow-up studies on neurodevelopmental outcome.

Prophylactic Low-Dose Paracetamol Administration for Ductal Closure and Amplitude-Integrated Electroencephalography in Preterm Infants

INTRODUCTION

Prophylactic low-dose paracetamol administration is used to induce closure of the ductus arteriosus in preterm infants. In our recent study we found no impairment on microstructural maturation processes in the brain of preterm infants at term-equivalent age following prophylactic low-dose paracetamol administration. We now assessed amplitude-integrated electroencephalography (aEEG) signals in preterm infants with and without exposure to prophylactic low-dose paracetamol administration.

METHODS

Infants <32 gestational weeks born between 10/2014 and 12/2018 received prophylactic paracetamol (10 mg/kg intravenously every 8 h until echocardiography after at least 72 h) and form the paracetamol group; infants born between 02/2011 and 09/2014 formed the control group. Four single parameters (continuity, cyclicity, amplitude of lower border, bandwidth span) together with their sum (Burdjalov total score) and presence of sleep-wake cycles were compared between the groups.

RESULTS

Included in the study were 338 infants. Two-hundred and seventeen infants received prophylactic paracetamol and 121 formed the control group. The paracetamol group showed a significantly higher number of sleep-wake cycles per hour and a significantly higher total scores compared to the control group (p < 0.05).

CONCLUSION

Paracetamol exposure has been regarded critically with respect to safety in preterm infants in recent years. We found no impairment on amplitude-integrated electroencephalography signals in preterm infants receiving low-dose prophylactic paracetamol compared to controls. Growing awareness and greater availability of data may encourage the clinicians to administer prophylactic paracetamol for ductal closure in preterm infants. The clinical relevance of our findings has to be evaluated in long-term follow up studies on neurodevelopmental outcome.

Strategies for the Emergency Treatment of Pregnant Women with Neurological Symptoms during the COVID-19 Pandemic

Coronavirus disease-19 (COVID-19) has been spreading all over the world for more than two years. Though several kinds of vaccines are currently available, emergence of new variants, spike mutations and immune escape have raised new challenges. Pregnant women are vulnerable to respiratory infections due to their altered immune defence and surveillance functions. Besides, whether pregnant persons should receive a COVID-19 vaccine is still under debate because limited data are available on the efficacy and safety of receiving a vaccine during pregnancy. Physiological features and lack of effective protection making pregnant women at high risk of getting infected. Another concern is that pregnancy may trigger the onset of underlying existing neurological disease, which is highly similar to those neurological symptoms of pregnant women caused by COVID-19. These similarities interfere with diagnosis and delay timely and effective management. Therefore, providing efficient emergency support for pregnant women suffering from neurological symptoms caused by COVID-19 remains a challenge among neurologists and obstetricians. To improve the diagnosis and treatment efficiency of pregnant women with neurological symptoms, we propose an emergency management framework based on the clinicians' experience and available resources. This emergency care system aimed at addressing the conundrums faced by the emergency guarantee system under COVID-19 pandemic and could serve as a potential multisystem project for clinical practice and medical education.

Paracetamol use during pregnancy - a call for precautionary action

Paracetamol (N-acetyl-p-aminophenol (APAP), otherwise known as acetaminophen) is the active ingredient in more than 600 medications used to relieve mild to moderate pain and reduce fever. APAP is widely used by pregnant women as governmental agencies, including the FDA and EMA, have long considered APAP appropriate for use during pregnancy when used as directed. However, increasing experimental and epidemiological research suggests that prenatal exposure to APAP might alter fetal development, which could increase the risks of some neurodevelopmental, reproductive and urogenital disorders. Here we summarize this evidence and call for precautionary action through a focused research effort and by increasing awareness among health professionals and pregnant women. APAP is an important medication and alternatives for treatment of high fever and severe pain are limited. We recommend that pregnant women should be cautioned at the beginning of pregnancy to: forego APAP unless its use is medically indicated; consult with a physician or pharmacist if they are uncertain whether use is indicated and before using on a long-term basis; and minimize exposure by using the lowest effective dose for the shortest possible time. We suggest specific actions to implement these recommendations. This Consensus Statement reflects our concerns and is currently supported by 91 scientists, clinicians and public health professionals from across the globe.

Maternal Immune Activation Hypotheses for Human Neurodevelopment: Some Outstanding Questions

The Maternal Immune Activation (MIA) hypothesis is a leading model for understanding prenatal influences on individual differences in, and clinical syndromes of, neurodevelopment. Experimental animal and human research has proliferated in recent years, and there is now a sizable research base. Several meta-analyses demonstrate general support for an association between prenatal immune activation and neurodevelopment in human research. However, questions remain about the nature of the immune activation, the network of underlying mechanisms involved, and the breadth of impact across behavioral phenotypes. Complementing recent reviews of results, the current review places particular emphasis on how advances in understanding mechanisms may be improved with greater attention to addressing the methodological variation and limitations of existing studies, and identifies areas for further clinical research.

Paracetamol (Acetaminophen) and the Developing Brain

Paracetamol is commonly used to treat fever and pain in pregnant women, but there are growing concerns that this may cause attention deficit hyperactivity disorder and autism spectrum disorder in the offspring. A growing number of epidemiological studies suggests that relative risks for these disorders increase by an average of about 25% following intrauterine paracetamol exposure. The data analyzed point to a dose-effect relationship but cannot fully account for unmeasured confounders, notably indication and genetic transmission. Only few experimental investigations have addressed this issue. Altered behavior has been demonstrated in offspring of paracetamol-gavaged pregnant rats, and paracetamol given at or prior to day 10 of life to newborn mice resulted in altered locomotor activity in response to a novel home environment in adulthood and blunted the analgesic effect of paracetamol given to adult animals. The molecular mechanisms that might mediate these effects are unknown. Paracetamol has diverse pharmacologic actions. It reduces prostaglandin formation via competitive inhibition of the peroxidase moiety of prostaglandin H2 synthase, while its metabolite N-arachidonoyl-phenolamine activates transient vanilloid-subtype 1 receptors and interferes with cannabinoid receptor signaling. The metabolite N-acetyl-p-benzo-quinone-imine, which is pivotal for liver damage after overdosing, exerts oxidative stress and depletes glutathione in the brain already at dosages below the hepatic toxicity threshold. Given the widespread use of paracetamol during pregnancy and the lack of safe alternatives, its impact on the developing brain deserves further investigation.

Prenatal and postnatal exposure to acetaminophen in relation to autism spectrum and attention-deficit and hyperactivity symptoms in childhood: Meta-analysis in six European population-based cohorts

The potential etiological role of early acetaminophen exposure on Autism Spectrum Conditions (ASC) and Attention-Deficit/Hyperactivity Disorder (ADHD) is inconclusive. We aimed to study this association in a collaborative study of six European population-based birth/child cohorts. A total of 73,881 mother-child pairs were included in the study. Prenatal and postnatal (up to 18 months) acetaminophen exposure was assessed through maternal questionnaires or interviews. ASC and ADHD symptoms were assessed at 4-12 years of age using validated instruments. Children were classified as having borderline/clinical symptoms using recommended cutoffs for each instrument. Hospital diagnoses were also available in one cohort. Analyses were adjusted for child and maternal characteristics along with indications for acetaminophen use. Adjusted cohort-specific effect estimates were combined using random-effects meta-analysis. The proportion of children having borderline/clinical symptoms ranged between 0.9 and 12.9% for ASC and between 1.2 and 12.2% for ADHD. Results indicated that children prenatally exposed to acetaminophen were 19% and 21% more likely to subsequently have borderline or clinical ASC (OR = 1.19, 95% CI 1.07-1.33) and ADHD symptoms (OR = 1.21, 95% CI 1.07-1.36) compared to non-exposed children. Boys and girls showed higher odds for ASC and ADHD symptoms after prenatal exposure, though these associations were slightly stronger among boys. Postnatal exposure to acetaminophen was not associated with ASC or ADHD symptoms. These results replicate previous work and support providing clear information to pregnant women and their partners about potential long-term risks of acetaminophen use.

Perinatal Acetaminophen Exposure and Childhood Attention-Deficit/Hyperactivity Disorder (ADHD): Exploring the Role of Umbilical Cord Plasma Metabolites in Oxidative Stress Pathways

Oxidative stress mechanisms may explain associations between perinatal acetaminophen exposure and childhood attention-deficit hyperactivity disorder (ADHD). We investigated whether the changes in umbilical cord plasma amino acids needed to synthesize the antioxidant glutathione and in the oxidative stress biomarker 8-hydroxy-deoxyguanosine may explain the association between cord plasma acetaminophen and ADHD in the Boston Birth Cohort (BBC). Mother–child dyads were followed at the Boston Medical Center between 1998 and 2018. Cord plasma analytes were measured from archived samples collected at birth. Physician diagnoses of childhood ADHD were obtained from medical records. The final sample consisted of 568 participants (child mean age [SD]: 9.3 [3.5] years, 315 (52.8%) male, 248 (43.7%) ADHD, 320 (56.3%) neurotypical development). Cord unmetabolized acetaminophen was positively correlated with methionine (R = 0.33, p < 0.001), serine (R = 0.30, p < 0.001), glycine (R = 0.34, p < 0.001), and glutamate (R = 0.16, p < 0.001). Children with cord acetaminophen levels >50th percentile appeared to have higher risk of ADHD for each increase in cord 8-hydroxy-deoxyguanosine level. Adjusting for covariates, increasing cord methionine, glycine, serine, and 8-hydroxy-deoxyguanosine were associated with significantly higher odds for childhood ADHD. Cord methionine statistically mediated 22.1% (natural indirect effect logOR = 0.167, SE = 0.071, p = 0.019) and glycine mediated 22.0% (natural indirect effect logOR = 0.166, SE = 0.078, p = 0.032) of the association between cord acetaminophen >50th percentile with ADHD. Our findings provide some clues, but additional investigation into oxidative stress pathways and the association of acetaminophen exposure and childhood ADHD is warranted.

Self-Medication Among Pregnant Women: Prevalence and Associated Factors

Objectives: The pregnancy period, with its peculiarities and specific symptoms that may or may not be physiological, can lead to medication use through prescription or even self-medication. This study aimed to assess self-medication practices among pregnant women, the most used medications, symptoms reported, and factors associated with this practice. Methods: This was a cross-sectional study conducted with pregnant women with an antenatal care (ANC) appointment in a tertiary teaching hospital referral in women's health. From April 2019 to February 2020, 297 pregnant women were interviewed. Self-medication was considered as the use of any medicine (including medicinal plants (MPs), herbal products, and vitamins) without a medical or dental prescription. The period considered to assess self-medication practice was the last 60 days prior to the study interview. Results: Among the 297 women interviewed, 107 (36.0%) had practiced self-medication in the previous 60 days. Acetaminophen was the most used medication, and headache was the most frequent symptom reported by self-medicated pregnant women. Pregnant women with high-school (73 (68.2%) (OR = 2.52; 95% CI 1.17-5.43; p = 0.018)) or university-level (23 (21.5%) (OR = 2.82; 95% CI 1.15-6.94; p = 0.024)) education had a higher risk of practicing self-medication when compared to women with lower education. Women in the first gestational trimester (35 (32.7%) (OR = 3.61; 95% CI 1.64-7.96; p = 0.002)) and with two or more pregnancies (87 (81.2%) (OR = 1.96; 95% CI 1.07-3.60; p = 0.029)) were more likely to practice self-medication than pregnant women in the second or third gestational trimester and in the first pregnancy, respectively. Conclusion: Self-medication was practiced by a considerable proportion of our sample, with the majority being OTC drugs. The factors associated with self-medication can help to improve prevention strategies regarding self-medication during pregnancy.

Physiological mediators of prenatal environmental influences in autism spectrum disorder

Recent research has pointed to the importance of the prenatal environment in the etiology of autism spectrum disorder (ASD) but the biological mechanisms which mitigate these environmental factors are not clear. Mitochondrial metabolism abnormalities, inflammation and oxidative stress as common physiological disturbances associated with ASD. Network analysis of the scientific literature identified several leading prenatal environmental factors associated with ASD, particularly air pollution, pesticides, the microbiome and epigenetics. These leading prenatal environmental factors were found to be most associated with inflammation, followed by oxidative stress and mitochondrial dysfunction. Other prenatal factors associated with ASD not identified by the network analysis were also found to be significantly associated with these common physiological disturbances. A better understanding of the biological mechanism which mediate the effect of prenatal environmental factors can lead to insights of how ASD develops and the development of targeted therapeutics to prevent ASD from occuring.

Prenatal exposure to acetaminophen increases the risk of atopic dermatitis in children: A nationwide nested case-control study in Taiwan

BACKGROUND

Acetaminophen (APAP) has been associated with the development of atopic diseases. However, little is known about the relationship between prenatal APAP exposure and atopic dermatitis (AD) in offspring.

OBJECTIVE

To investigate the association between prenatal APAP exposure and AD risk in offspring.

METHODS

In this study, 2029 study pairs (AD-affected children and their mothers) and 5,058 control pairs were identified between 1998 and 2008 from the Taiwan Longitudinal Health Insurance Database. Maternal APAP exposure during pregnancy was assessed.

RESULTS

After adjustment for potential confounders, there was a significant association between risk of offspring AD and exposure to acetaminophen in the first trimester (OR 1.16; 95% CI 1.05-1.28), the second trimester (OR 1.14; 95% CI 1.03-1.27), both first and second trimesters (OR 1.30; 95% CI 1.13-1.51), both first and third trimester (OR 1.20; 95% CI 1.04-1.39), any trimester (OR 1.12; 95% CI 1.00-1.26), and all three trimesters (OR 1.32; 95% CI 1.08-1.62) in a dose-response manner.

CONCLUSIONS

Prenatal exposure to acetaminophen was associated with an increased incidence of offspring AD.

Acetaminophen Therapy for Persistent Patent Ductus Arteriosus

Persistence of a left-to-right shunt caused by a patent ductus arteriosus (PDA) leads to significant sequelae in extremely premature infants as a result of pulmonary overcirculation and systemic steal. Although timing and duration of treatment for a persistent clinically significant PDA differ among institutions, standard pharmacologic interventions are the nonsteroidal anti-inflammatory drugs indomethacin and ibuprofen. Acetaminophen has emerged as an alternative to indomethacin and ibuprofen with less significant adverse effects, but there is no consensus regarding its use. This review summarizes the most recent evidence for the use of acetaminophen in PDA treatment.

Prenatal medication exposure and epigenetic outcomes: a systematic literature review and recommendations for prenatal pharmacoepigenetic studies

When used during pregnancy, analgesics and psychotropics pass the placenta to enter the foetal circulation and may induce epigenetic modifications. Where such modifications occur and whether they disrupt normal foetal developme nt, are currently unanswered questions. This field of prenatal pharmacoepigenetics has received increasing attention, with several studies reporting associations between in utero medication exposure and offspring epigenetic outcomes. Nevertheless, no recent systematic review of the literature is available. Therefore, the objectives of this review were to (i) provide an overview of the literature on the association of prenatal exposure to psychotropics a nd analgesics with epigenetic outcomes, and (ii) suggest recommendations for future studies within prenatal pharmacoepigenetics. We performed systematic literature searches in five databases. The eligible studies assessed human prenatal exposure to psychotropics or analgesics, with epigenetic analyses of offspring tissue as an outcome. We identified 18 eligible studies including 4,419 neonates exposed to either antidepressants, antiepileptic drugs, paracetamol, acetylsalicylic acid, or methadone. The epigenetic outcome in all studies was DNA methylation in cord blood, placental tissue or buccal cells. Although most studies found significant differences in DNA methylation upon medication exposure, almost no differences were persistent across studies for similar medications and sequencing methods. The reviewed studies were challenging to compare due to poor transparency in reporting, and heterogeneous methodology, design, genome coverage, and statistical modelling. We propose 10 recommendations for future prenatal pharmacoepigenetic studies considering both epidemiological and epigenetic perspectives. These recommendations may improve the quality, comparability, and clinical relevance of such studies. PROSPERO registration ID: CRD42020166675.

DNA methylation in cord blood in association with prenatal depressive symptoms

BACKGROUND

Prenatal symptoms of depression (PND) and anxiety affect up to every third pregnancy. Children of mothers with mental health problems are at higher risk of developmental problems, possibly through epigenetic mechanisms together with other factors such as genetic and environmental. We investigated DNA methylation in cord blood in relation to PND, taking into consideration a history of depression, co-morbidity with anxiety and selective serotonin reuptake inhibitors (SSRI) use, and stratified by sex of the child. Mothers (N = 373) prospectively filled out web-based questionnaires regarding mood symptoms and SSRI use throughout pregnancy. Cord blood was collected at birth and DNA methylation was measured using Illumina MethylationEPIC array at 850 000 CpG sites throughout the genome. Differentially methylated regions were identified using Kruskal-Wallis test, and Benjamini-Hochberg adjusted p-values < 0.05 were considered significant.

RESULTS

No differential DNA methylation was associated with PND alone; however, differential DNA methylation was observed in children exposed to comorbid PND with anxiety symptoms compared with healthy controls in ABCF1 (log twofold change - 0.2), but not after stratification by sex of the child. DNA methylation in children exposed to PND without SSRI treatment and healthy controls both differed in comparison with SSRI exposed children at several sites and regions, among which hypomethylation was observed in CpGs in the promoter region of CRBN (log2 fold change - 0.57), involved in brain development, and hypermethylation in MDFIC (log2 fold change 0.45), associated with the glucocorticoid stress response.

CONCLUSION

Although it is not possible to assess if these methylation differences are due to SSRI treatment itself or to more severe depression, our findings add on to existing knowledge that there might be different biological consequences for the child depending on whether maternal PND was treated with SSRIs or not.

Perinatal exposure to paracetamol: Dose and sex-dependent effects in behaviour and brain's oxidative stress markers in progeny

Paracetamol (PAR) has been employed worldwide for pain and fever treatment during pregnancy and lactation. Epidemiologic studies have shown that exposure to PAR can increase the risk for developmental disorders, such as attention-deficit hyperactive disorder and autism spectrum disorder. This study aimed to investigate if gestational and lactational exposure to human-relevant doses of PAR could alter behavioural and brain oxidative stress parameters in the rat`s offspring. Wistar dams were gavaged daily with water or PAR (35 mg/kg/ or 350 mg/kg) during gestational day 6 to weaning (postnatal day 21). Behavioural assessments occurred at post-natal days 10 (nest seeking test), 27 (behavioural stereotypy) and 28 (three chamber sociability test and open field). Concentration of advanced oxidation protein products (AOPP), reduced glutathione (GSH), lipid hydroperoxides (LOOH) and activity of superoxide dismutase (SOD) were estimate in prefrontal cortex, hippocampus, striatum and cerebellum of 22-day-old rats. Compared to CON animals, males exposed to PAR during pregnancy and lactation augmented apomorphine-induced stereotyped behaviour (350 mg/kg) and ambulation in open-field test (35 mg/kg). Reduced exploratory behaviour in three chamber sociability test was observed in pups exposed to PAR at 350 mg/kg in both sexes. PAR treatment decreased hippocampal GSH level and striatal SOD activity in males exposed to 35 mg/kg, suggesting the vulnerability of these areas in PAR-induced developmental neurotoxicity. Findings suggest PAR use during pregnancy and lactation as a potential risk factor for neurodevelopmental disorders with males being more susceptible.

Mitochondria May Mediate Prenatal Environmental Influences in Autism Spectrum Disorder

We propose that the mitochondrion, an essential cellular organelle, mediates the long-term prenatal environmental effects of disease in autism spectrum disorder (ASD). Many prenatal environmental factors which increase the risk of developing ASD influence mitochondria physiology, including toxicant exposures, immune activation, and nutritional factors. Unique types of mitochondrial dysfunction have been associated with ASD and recent studies have linked prenatal environmental exposures to long-term changes in mitochondrial physiology in children with ASD. A better understanding of the role of the mitochondria in the etiology of ASD can lead to targeted therapeutics and strategies to potentially prevent the development of ASD.

Intrauterine Exposure to Acetaminophen and Adverse Developmental Outcomes: Epidemiological Findings and Methodological Issues

PURPOSE OF REVIEW

Acetaminophen (or paracetamol) is one of the most commonly used medications during pregnancy. We reviewed recent epidemiological evidence regarding intrauterine exposure to acetaminophen and risk for asthma, neurodevelopment disorders, and reproductive health in childhood.

RECENT FINDINGS

An increasing number of cohort studies have suggested that maternal use of acetaminophen during pregnancy was associated with increased risk for asthma; neurodevelopmental disorders, especially ADHD and behavioral problems; and genital malformations in the offspring. Oxidative stress and inflammation or endocrine effects are plausible shared biological mechanisms for the exposure to influence multiple developmental outcomes. We discussed methodological challenges that can threaten the validity of these observational data, including confounding and measurement errors. Novel statistical methods and research designs that can be used to mitigate these issues were introduced. Given the high prevalence of use, findings regarding intrauterine exposure to acetaminophen on multiple child health outcomes raise concerns. Research on causal and non-causal mechanisms that might explain these associations should be a priority.

Is late treatment with acetaminophen safe and effective in avoiding surgical ligation among extremely preterm neonates with persistent patent ductus arteriosus?

OBJECTIVE

Evaluate the association of late treatment with acetaminophen vs. immediate surgical ligation with death or neurodevelopmental impairment (NDI) among extremely low gestational age neonates (ELGANs) with persistent patent ductus arteriosus (pPDA).

STUDY DESIGN

Retrospective comparative epoch study of ELGANs with pPDA being considered for surgical ligation. ELGANs in epoch 1 (2009-2012) were referred for ligation, while infants in epoch 2 (2012-2015) were treated with oral acetaminophen and referred for ligation in the absence of improvement. The primary outcome was a composite of death/NDI at 18-24 months.

RESULTS

Ninety-two ELGANs with median[IQR] GA 25.2 weeks [24.4, 26.3] had pPDA (43 in epoch 1, 49 in -epoch 2) with acetaminophen-exposed neonates receiving 7 days [7, 7] of treatment. ELGANs in epoch 2 had reduced ligation (aOR 0.30; 95%CI: [0.11, 0.87]), but there was no difference in death/NDI (aOR 1.03; 95%CI: [0.30, 3.56]).

CONCLUSIONS

Late treatment with acetaminophen to avoid surgery for pPDA is associated with reduced ligation but no difference in death/NDI, supporting the safety and effectiveness of this approach.

Evaluation of the dentate gyrus in adult mice exposed to acetaminophen (paracetamol) on postnatal day 10

Acetaminophen (AAP; or paracetamol) is a widely used nonprescription drug with antipyretic and analgesic properties. Alarmingly, there is an increasing body of evidence showing that developmental exposure to AAP is associated with adverse behavioural outcomes later in life. We have previously shown that relevant doses of AAP in 10-day-old mice affected memory, learning and locomotor activity in the adult animals. Interestingly, the neurons of the dentate gyrus (DG) have a relatively late time of origin as they are generated during the first two weeks of postnatal life in rodents. Since the generation of these cells, which are important for memory processing, coincides with our AAP exposure, we aim to investigate if the cytoarchitecture of the DG is affected by postnatal day 10 AAP treatment. In addition, we investigate if markers for differentiation and migration in the hippocampus were affected by the same treatment. We did not observe any visual effects in adult DG cytoarchitecture, nor any changes of markers for differentiation/migration in the hippocampus in 24 hr after exposure. Even though a large effect size was estimated on adult DG thickness following AAP exposure, the estimated 95% CIs around the differences of the means reveal no significant effect. Hence, larger sample sizes are warranted to clarify if neonatal AAP exposure affects adult DG thickness in mice.

Environmental risk factors, protective factors, and peripheral biomarkers for ADHD: an umbrella review

BACKGROUND

Many potential environmental risk factors, environmental protective factors, and peripheral biomarkers for ADHD have been investigated, but the consistency and magnitude of their effects are unclear. We aimed to systematically appraise the published evidence of association between potential risk factors, protective factors, or peripheral biomarkers, and ADHD.

METHODS

In this umbrella review of meta-analyses, we searched PubMed including MEDLINE, Embase, and the Cochrane Database of Systematic Reviews, from database inception to Oct 31, 2019, and screened the references of relevant articles. We included systematic reviews that provided meta-analyses of observational studies that examined associations of potential environmental risk factors, environmental protective factors, or peripheral biomarkers with diagnosis of ADHD. We included meta-analyses that used categorical ADHD diagnosis criteria according to DSM, hyperkinetic disorder according to ICD, or criteria that were less rigorous than DSM or ICD, such as self-report. We excluded articles that did not examine environmental risk factors, environmental protective factors, or peripheral biomarkers of ADHD; articles that did not include a meta-analysis; and articles that did not present enough data for re-analysis. We excluded non-human studies, primary studies, genetic studies, and conference abstracts. We calculated summary effect estimates (odds ratio [OR], relative risk [RR], weighted mean difference [WMD], Cohen's d, and Hedges' g), 95% CI, heterogeneity I² statistic, 95% prediction interval, small study effects, and excess significance biases. We did analyses under credibility ceilings, and assessed the quality of the meta-analyses with AMSTAR 2 (A Measurement Tool to Assess Systematic Reviews 2). This study is registered with PROSPERO, number CRD42019145032.

FINDINGS

We identified 1839 articles, of which 35 were eligible for inclusion. These 35 articles yielded 63 meta-analyses encompassing 40 environmental risk factors and environmental protective factors (median cases 16 850, median population 91 954) and 23 peripheral biomarkers (median cases 175, median controls 187). Evidence of association was convincing (class I) for maternal pre-pregnancy obesity (OR 1·63, 95% CI 1·49 to 1·77), childhood eczema (1·31, 1·20 to 1·44), hypertensive disorders during pregnancy (1·29, 1·22 to 1·36), pre-eclampsia (1·28, 1·21 to 1·35), and maternal acetaminophen exposure during pregnancy (RR 1·25, 95% CI 1·17 to 1·34). Evidence of association was highly suggestive (class II) for maternal smoking during pregnancy (OR 1·6, 95% CI 1·45 to 1·76), childhood asthma (1·51, 1·4 to 1·63), maternal pre-pregnancy overweight (1·28, 1·21 to 1·35), and serum vitamin D (WMD -6·93, 95% CI -9·34 to -4·51).

INTERPRETATION

Maternal pre-pregnancy obesity and overweight; pre-eclampsia, hypertension, acetaminophen exposure, and smoking during pregnancy; and childhood atopic diseases were strongly associated with ADHD. Previous familial studies suggest that maternal pre-pregnancy obesity, overweight, and smoking during pregnancy are confounded by familial or genetic factors, and further high-quality studies are therefore required to establish causality.

FUNDING

None.