Association of maternal and infant variants in PNOC and COMT genes with neonatal abstinence syndrome severity

Predicting Heterogeneity in Patient Response to Morphine Treatment for Neonatal Opioid Withdrawal Syndrome

Infants with neonatal opioid withdrawal syndrome commonly receive morphine treatment to manage their withdrawal signs. However, the effectiveness of this pharmacotherapy in managing the infants' withdrawal signs vary widely. We sought to understand how information available early in infant monitoring can anticipate this treatment response, focusing on early modified Finnegan Neonatal Abstinence Scoring System (FNASS) scores, polygenic risk for opioid dependence (polygenic risk score (PRS)), and drug exposure. Using k-means clustering, we divided the 213 infants in our cohort into 3 groups based on their FNASS scores in the 12 hours before and after the initiation of pharmacotherapy. We found that these groups were pairwise significantly different for risk factors, including methadone exposure, and for in-hospital outcomes, including total morphine received, length of stay, and highest FNASS score. Whereas PRS was not predictive of receipt of treatment, PRS was pairwise significantly different between a subset of the groups. Using tree-based machine learning methods, we then constructed network graphs of the relationships among these groups, FNASS scores, PRS, drug exposures, and in-hospital outcomes. The resulting networks also showed meaningful connection between early FNASS scores and PRS, as well as between both of those and later in-hospital outcomes. These analyses present clinicians with the opportunity to better anticipate infant withdrawal progression and prepare accordingly, whether with expedited morphine treatment or non-pharmacotherapeutic alternative treatments.

Guideline No. 443b: Opioid Use Throughout Women's Lifespan: Opioid Use in Pregnancy and Breastfeeding

OBJECTIVE

To provide health care providers the best evidence on opioid use and women's health. Areas of focus include pregnancy and postpartum care.

TARGET POPULATION

The target population includes all women currently using or contemplating using opioids.

OUTCOMES

Open, evidence-informed dialogue about opioid use will improve patient care.

BENEFITS, HARMS, AND COSTS

Exploring opioid use through a trauma-informed approach provides the health care provider and patient with an opportunity to build a strong, collaborative, and therapeutic alliance. This alliance empowers women to make informed choices about their own care. It also allows for the diagnosis and possible treatment of opioid use disorders. Opioid use should not be stigmatized, as stigma leads to poor "partnered care" (i.e., the partnership between the patient and care provider). Health care providers need to understand the effect opioids can have on pregnant women and support them to make knowledgeable decisions about their health.

EVIDENCE

A literature search was designed and carried out in PubMed and the Cochrane Library databases from August 2018 until March 2023 using following MeSH terms and keywords (and variants): opioids, opioid agonist therapy, illicit drugs, fertility, pregnancy, fetal development, neonatal abstinence syndrome, and breastfeeding.

VALIDATION METHODS

The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and conditional [weak] recommendations).

INTENDED AUDIENCE

All health care providers who care for pregnant and/or post-partum women and their newborns.

TWEETABLE ABSTRACT

Opioid use during pregnancy often co-occurs with mental health issues and is associated with adverse maternal, fetal, and neonatal outcomes; treatment of opioid use disorder with agonist therapy for pregnant women can be safe during pregnancy where the risks outnumber the benefits.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Directive clinique no 443b : Opioïdes aux différentes étapes de la vie des femmes : Grossesse et allaitement

OBJECTIF

Présenter aux professionnels de la santé les données probantes concernant l'utilisation des opioïdes et la santé des femmes. Les domaines d'intérêt sont la grossesse et les soins post-partum.

POPULATION CIBLE

Toutes les femmes qui utilisent des opioïdes. RéSULTATS: Un dialogue ouvert et éclairé sur l'utilisation des opioïdes améliorera les soins aux patientes. BéNéFICES, RISQUES ET COûTS: L'exploration de l'utilisation d'opioïdes par une approche tenant compte des traumatismes antérieurs donne au professionnel de la santé et à la patiente l'occasion de bâtir une alliance solide, collaborative et thérapeutique. Cette alliance permet aux femmes de faire des choix éclairés. Elle favorise le diagnostic et le traitement possible du trouble lié à l'utilisation d'opioïdes. L'utilisation ne doit pas être stigmatisée, puisque la stigmatisation affaiblit le partenariat (le partenariat entre patiente et professionnel de la santé). Les professionnels de la santé ceus-ci doivent comprendre l'effet potentiel des opioïdes sur la santé les femmes enceintes et les aider à prendre des décisions éclairées sur leur santé. DONNéES PROBANTES: Une recherche a été conçue puis effectuée dans les bases de données PubMed et Cochrane Library pour la période d'août 2018 à mars 2023 des termes MeSH et mots clés suivants (et variantes) : opioids, opioid agonist therapy, illicit drugs, fertility, pregnancy, fetal development, neonatal abstinence syndrome et breastfeeding. MéTHODES DE VALIDATION: Les auteurs ont évalué la qualité des données probantes et la force des recommandations en utilisant le cadre méthodologique GRADE (Grading of Recommendations, Assessment, Development, and Evaluation). Voir l'annexe A en ligne (tableau A1 pour les définitions et tableau A2 pour l'interprétation des recommandations fortes et conditionnelles [faibles]). PROFESSIONNELS CONCERNéS: Tous les professionnels de la santé qui prodiguent des soins aux femmes et aux nouveaux-nés. RéSUMé POUR TWITTER: La consommation d'opioïdes pendant la grossesse coïncide souvent avec des problèmes de santé mentale et est associée à des conséquences néfastes pour la mère, le fœtus et le nouveau-né ; le traitement des troubles liés à la consommation d'opioïdes par agonistes peut être sûr pendant la grossesse lorsque les risques sont plus nombreux que les avantages. DÉCLARATIONS SOMMAIRES: RECOMMANDATIONS.

Effect of Neonatal Abstinence Syndrome Treatment Status and Maternal Depressive Symptomatology on Maternal Reports of Infant Behaviors

OBJECTIVE

The objective of this study is to investigate the effects of maternal perinatal depression symptoms and infant treatment status for neonatal abstinence syndrome (NAS) on maternal perceptions of infant regulatory behavior at 6 weeks of age.

METHODS

Mothers and their infants (N = 106; 53 dyads) were recruited from a rural, White cohort in Northeast Maine. Mothers in medication-assisted treatment (methadone) and their infants (n = 35 dyads) were divided based on the infant's NAS pharmacological treatment (n = 20, NAS+ group; n = 15, NAS- group) and compared with a demographically similar, nonexposed comparison group (n = 18 dyads; COMP group). At 6 weeks postpartum, mothers reported their depression symptoms Beck Depression Inventory-2nd Edition) and infant regulatory behaviors [Mother and Baby Scales (MABS)]. Infant neurobehavior was assessed during the same visit using the Neonatal Network Neurobehavioral Scale (NNNS).

RESULTS

Mothers in the NAS+ group showed significantly higher depression scores than the COMP group (p < .05) while the NAS- group did not. Across the sample, mothers with higher depression scores reported higher infant "unsettled-irregularity" MABS scores, regardless of group status. Agreement between maternal reports of infant regulatory behaviors and observer-assessed NNNS summary scares was poor in both the NAS+ and COMP groups.

CONCLUSIONS

Postpartum women in opioid recovery with infants requiring pharmacological intervention for NAS are more at risk for depression which may adversely influence their perceptions of their infants' regulatory profiles. Unique, targeted attachment interventions may be needed for this population.

Placental microRNA methylome signatures may serve as biomarkers and therapeutic targets for prenatally opioid-exposed infants with neonatal opioid withdrawal syndrome

Introduction: The neonate exposed to opioids in utero faces a constellation of withdrawal symptoms postpartum commonly called neonatal opioid withdrawal syndrome (NOWS). The incidence of NOWS has increased in recent years due to the opioid epidemic. MicroRNAs (miRNAs) are small non-coding RNA molecules that play a crucial role in gene regulation. Epigenetic variations in microRNAs (miRNAs) and their impact on addiction-related processes is a rapidly evolving area of research. Methods: The Illumina Infinium Methylation EPIC BeadChip was used to analyze DNA methylation levels of miRNA-encoding genes in 96 human placental tissues to identify miRNA gene methylation profiles as-sociated with NOWS: 32 from mothers whose prenatally opioid-exposed infants required pharmacologic management for NOWS, 32 from mothers whose prenatally opioid-exposed infants did not require treat-ment for NOWS, and 32 unexposed controls. Results: The study identified 46 significantly differentially methylated (FDR p-value ≤ 0.05) CpGs associated with 47 unique miRNAs, with a receiver operating characteristic (ROC) area under the curve (AUC) ≥0.75 including 28 hypomethylated and 18 hypermethylated CpGs as potentially associated with NOWS. These dysregulated microRNA methylation patterns may be a contributing factor to NOWS pathogenesis. Conclusion: This is the first study to analyze miRNA methylation profiles in NOWS infants and illustrates the unique role miRNAs might have in diagnosing and treating the disease. Furthermore, these data may provide a step toward feasible precision medicine for NOWS babies as well.

Polygenic risk scores and the need for pharmacotherapy in neonatal abstinence syndrome

BACKGROUND

The aim of this study was to identify genetic variants associated with NAS through a genome-wide association study (GWAS) and estimate a Polygenic Risk Score (PRS) model for NAS.

METHODS

A prospective case-control study included 476 in utero opioid-exposed term neonates. A GWAS of 1000 genomes-imputed genotypes was performed to identify variants associated with need for pharmacotherapy for NAS. PRS models for estimating genetic predisposition were generated via a nested cross-validation approach using 382 neonates of European ancestry. PRS predictive ability, discrimination, and calibration were assessed.

RESULTS

Cross-ancestry GWAS identified one intergenic locus on chromosome 7 downstream of SNX13 exhibiting genome-wide association with need for pharmacotherapy. PRS models derived from the GWAS for a subset of the European ancestry neonates reliably discriminated between need for pharmacotherapy using cis variant effect sizes within validation sets of European and African American ancestry neonates. PRS were less effective when applying variant effect sizes across datasets and in calibration analyses.

CONCLUSIONS

GWAS has the potential to identify genetic loci associated with need for pharmacotherapy for NAS and enable development of clinically predictive PRS models. Larger GWAS with additional ancestries are needed to confirm the observed SNX13 association and the accuracy of PRS in NAS risk prediction models.

IMPACT

Genetic associations appear to be important in neonatal abstinence syndrome. This is the first genome-wide association in neonates with neonatal abstinence syndrome. Polygenic risk scores can be developed examining single-nucleotide polymorphisms across the entire genome. Polygenic risk scores were higher in neonates receiving pharmacotherapy for treatment of their neonatal abstinence syndrome. Future studies with larger cohorts are needed to better delineate these genetic associations.

A review of the genomics of neonatal abstinence syndrome

Neonatal abstinence syndrome (NAS) is a constellation of signs of withdrawal occurring after birth following in utero exposure to licit or illicit opioids. Despite significant research and public health efforts, NAS remains challenging to diagnose, predict, and manage due to highly variable expression. Biomarker discovery in the field of NAS is crucial for stratifying risk, allocating resources, monitoring longitudinal outcomes, and identifying novel therapeutics. There is considerable interest in identifying important genetic and epigenetic markers of NAS severity and outcome that can guide medical decision making, research efforts, and public policy. A number of recent studies have suggested that genetic and epigenetic changes are associated with NAS severity, including evidence of neurodevelopmental instability. This review will provide an overview of the role of genetics and epigenetics in short and longer-term NAS outcomes. We will also describe novel research efforts using polygenic risk scores for NAS risk stratification and salivary gene expression to understand neurobehavioral modulation. Finally, emerging research focused on neuroinflammation from prenatal opioid exposure may elucidate novel mechanisms that could lead to development of future novel therapeutics.

Perinatal Morphine Exposure Leads to Sex-Dependent Executive Function Deficits and Microglial Changes in Mice

Children exposed prenatally to opioids are at an increased risk for behavioral problems and executive function deficits. The prefrontal cortex (PFC) and amygdala (AMG) regulate executive function and social behavior and are sensitive to opioids prenatally. Opioids can bind to toll-like receptor 4 (TLR4) to activate microglia, which may be developmentally important for synaptic pruning. Therefore, we tested the effects of perinatal morphine exposure on executive function and social behavior in male and female mouse offspring, along with microglial-related and synaptic-related outcomes. Dams were injected once daily subcutaneously with saline (n = 8) or morphine (MO; 10 mg/kg; n = 12) throughout pregestation, gestation, and lactation until offspring were weaned on postnatal day 21 (P21). Male MO offspring had impairments in attention and accuracy in the five-choice serial reaction time task, while female MO offspring were less affected. Targeted gene expression analysis at P21 in the PFC identified alterations in microglial-related and TLR4-related genes, while immunohistochemical analysis in adult brains indicated decreased microglial Iba1 and phagocytic CD68 proteins in the PFC and AMG in males, but females had an increase. Further, both male and female MO offspring had increased social preference. Overall, these data demonstrate male vulnerability to executive function deficits in response to perinatal opioid exposure and evidence for disruptions in neuron-microglial signaling.

The Impact of Pharmacogenetics on Pharmacokinetics and Pharmacodynamics in Neonates and Infants: A Systematic Review

In neonates, pharmacogenetics has an additional layer of complexity. This is because in addition to genetic variability in genes that code for proteins relevant to clinical pharmacology, there are rapidly maturational changes in these proteins. Consequently, pharmacotherapy in neonates has unique challenges. To provide a contemporary overview on pharmacogenetics in neonates, we conducted a systematic review to identify, describe and quantify the impact of pharmacogenetics on pharmacokinetics and -dynamics in neonates and infants (PROSPERO, CRD42022302029). The search was performed in Medline, Embase, Web of Science and Cochrane, and was extended by a PubMed search on the ‘top 100 Medicines’ (medicine + newborn/infant + pharmacogen*) prescribed to neonates. Following study selection (including data in infants, PGx related) and quality assessment (Newcastle–Ottawa scale, Joanna Briggs Institute tool), 55/789 records were retained. Retained records relate to metabolizing enzymes involved in phase I [cytochrome P450 (CYP1A2, CYP2A6, CYP2B6, CYP2C8/C9/C18, CYP2C19, CYP2D6, CYP3A5, CYP2E1)], phase II [glutathione-S-transferases, N-acetyl transferases, UDP-glucuronosyl-transferase], transporters [ATP-binding cassette transporters, organic cation transporters], or receptor/post-receptor mechanisms [opioid related receptor and post-receptor mechanisms, tumor necrosis factor, mitogen-activated protein kinase 8, vitamin binding protein diplotypes, corticotrophin-releasing hormone receptor-1, nuclear receptor subfamily-1, vitamin K epoxide reductase complex-1, and angiotensin converting enzyme variants]. Based on the available overview, we conclude that the majority of reported pharmacogenetic studies explore and extrapolate observations already described in older populations. Researchers commonly try to quantify the impact of these polymorphisms in small datasets of neonates or infants. In a next step, pharmacogenetic studies in neonatal life should go beyond confirmation of these associations and explore the impact of pharmacogenetics as a covariate limited to maturation of neonatal life (ie, fetal malformations, breastfeeding or clinical syndromes). The challenge is to identify the specific factors, genetic and non-genetic, that contribute to the best benefit/risk balance.

Racial differences in opioid withdrawal syndrome among neonates with intrauterine opioid exposure

BACKGROUND

The aim of this study was to investigate the association between race and severe neonatal opioid withdrawal syndrome (NOWS) in infants exposed to intrauterine opioids.

METHODS

This is a prospective observational study on intrauterine opioid-exposed term infants. Exposure to opioids was based on maternal disclosure, urine, or umbilical cord drug screening. Severe NOWS was defined based on modified Finnegan scoring and the need for pharmacological intervention.

RESULTS

One hundred and fifty mother-infant pairs, 60 Black and 90 White with history of opioid exposure during pregnancy, were included. More White than Black infants developed NOWS that required pharmacological treatment, 70 vs. 40%: RR = 1.75 (1.25-2.45). In adjusted analysis, there was no significant association between race and the development of severe NOWS in mothers who attended opioid maintenance treatment program (OMTP). However, in mothers who did not attend OMTP, White race remained a significant factor associated with the development of severe NAS, RR = 1.69 (1.06, 2.69).

CONCLUSIONS

Severe NOWS that required pharmacological intervention was significantly higher in White than in Black infants born to mothers who did not attend OMTP. Larger studies are needed to evaluate the association between social as well as genetic factors and the development of NOWS.

IMPACT

There is a significant association between race and development of severe NOWS.

Escaping the Finnegan - Is it time?

Neonatal Abstinence Syndrome (NAS) has significantly increased worldwide secondary to a marked increase in the incidence of opioid use disorders (OUD) in women of childbearing age. Since first described in 1975, the Finnegan Neonatal Abstinence Scoring Tool (FNAST) remains the mainstay of monitoring NAS severity and its clinical management. The complexity of the tool (21 independent variables), the need for external validation, excessive subjectivity, poor inter-rater reliability, and uncertainty regarding the clinical relevance of some items has resulted in the need to develop an alternate scoring tool. A validated, simple, clinically relevant, and universally accepted approach to assessing opioid exposed neonates would facilitate high quality clinical care while assisting in the generation of generalizable data from future research studies conducted in this vulnerable population.

Placental OPRM1 DNA methylation and associations with neonatal opioid withdrawal syndrome, a pilot study

Aims:

Epigenetic variation of DNA methylation of the mu-opioid receptor gene (OPRM1) has been identified in the blood and saliva of individuals with opioid use disorder (OUD) and infants with neonatal opioid withdrawal syndrome (NOWS). It is unknown whether epigenetic variation in OPRM1 exists within placental tissue in women with OUD and whether it is associated with NOWS outcomes. In this pilot study, the authors aimed to 1) examine the association between placental OPRM1 DNA methylation levels and NOWS outcomes, and 2) compare OPRM1 methylation levels in opioid-exposed versus non-exposed control placentas.

Methods:

Placental tissue was collected from eligible opioid (n = 64) and control (n = 29) women after delivery. Placental DNA was isolated and methylation levels at six cytosine-phosphate-guanine (CpG) sites within the OPRM1 promoter were quantified. Methylation levels were evaluated for associations with infant NOWS outcome measures: need for pharmacologic treatment, length of hospital stay (LOS), morphine treatment days, and treatment with two medications. Regression models were created and adjusted for clinical co-variates. Methylation levels between opioid and controls placentas were also compared.

Results:

The primary opioid exposures were methadone and buprenorphine. Forty-nine (76.6%) of the opioid-exposed infants required pharmacologic treatment, 10 (15.6%) two medications, and average LOS for all opioid-exposed infants was 16.5 (standard deviation 9.7) days. There were no significant associations between OPRM1 DNA methylation levels in the six CpG sites and any NOWS outcome measures. No significant differences were found in methylation levels between the opioid and control samples.

Conclusions:

No significant associations were found between OPRM1 placental DNA methylation levels and NOWS severity in this pilot cohort. In addition, no significant differences were seen in OPRM1 methylation in opioid versus control placentas. Future association studies examining methylation levels on a genome-wide level are warranted.

Placental DNA methylation profiles in opioid-exposed pregnancies and associations with the neonatal opioid withdrawal syndrome

Opioid abuse during pregnancy can result in Neonatal Opioid Withdrawal Syndrome (NOWS). We investigated genome-wide methylation analyses of 96 placental tissue samples, including 32 prenatally opioid-exposed infants with NOWS who needed therapy (+Opioids/+NOWS), 32 prenatally opioid-exposed infants with NOWS who did not require treatment (+Opioids/-NOWS), and 32 prenatally unexposed controls (-Opioids/-NOWS, control). Statistics, bioinformatics, Artificial Intelligence (AI), including Deep Learning (DL), and Ingenuity Pathway Analyses (IPA) were performed. We identified 17 dysregulated pathways thought to be important in the pathophysiology of NOWS and reported accurate AI prediction of NOWS diagnoses. The DL had an AUC (95% CI) =0.98 (0.95-1.0) with a sensitivity and specificity of 100% for distinguishing NOWS from the +Opioids/-NOWS group and AUCs (95% CI) =1.00 (1.0-1.0) with a sensitivity and specificity of 100% for distinguishing NOWS versus control and + Opioids/-NOWS group versus controls. This study provides strong evidence of methylation dysregulation of placental tissue in NOWS development.

Maternal and iatrogenic neonatal opioid withdrawal syndrome: Differences and similarities in recognition, management, and consequences

Opioids are potent analgesics used to manage pain in both young and old, but the increased use in the pregnant population has significant individual and societal implications. Infants dependent on opioids, either through maternal or iatrogenic exposure, undergo neonatal opioid withdrawal syndrome (NOWS), where they may experience withdrawal symptoms ranging from mild to severe. We present a detailed and original review of NOWS caused by maternal opioid exposure (mNOWS) and iatrogenic opioid intake (iNOWS). While these two entities have been assessed entirely separately, recognition and treatment of the clinical manifestations of NOWS overlap. Neonatal risk factors such as age, genetic predisposition, drug type, and clinical factors like type of opioid, cumulative dose of opioid exposure, and disease status affect the incidence of both mNOWS and iNOWS, as well as their severity. Recognition of withdrawal is dependent on clinical assessment of symptoms, and the use of clinical assessment tools designed to determine the need for pharmacotherapy. Treatment of NOWS relies on a combination of non-pharmacological therapies and pharmacological options. Long-term consequences of opioids and NOWS continue to generate controversy, with some evidence of anatomic brain changes, but conflicting animal and human clinical evidence of significant cognitive or behavioral impacts on school-age children. We highlight the current knowledge on clinically relevant recognition, treatment, and consequences of NOWS, and identify new advances in clinical management of the neonate. This review brings a unique clinical perspective and critically analyzes gaps between the clinical problem and our preclinical understanding of NOWS.

Neonatal Opioid Withdrawal Syndrome (NOWS): A Transgenerational Echo of the Opioid Crisis

The incidence of neonatal opioid withdrawal syndrome (NOWS) has increased substantially in the setting of the opioid epidemic, a major public health problem in the United States. At present, NOWS has commonly used assessment and treatment protocols, but new protocols have questioned old practices. However, because of limited access to opioid use disorder (OUD) treatment and socioeconomic factors, many pregnant (and postpartum) women with OUD do not receive treatment. The pathophysiology of NOWS is not completely understood, although limited research studies have been conducted in humans and animals to better understand its etiology. Moreover, there is evidence that epigenetic and genetic factors play a role in the development of NOWS, but further study is needed. Animal models have suggested that there are deleterious effects of in utero opioid exposure later in life. Clinical research has revealed the harmful long-term sequelae of NOWS, with respect to cognitive function and childhood development. Many psychiatric disorders begin during adolescence, so as infants born with NOWS approach adolescence, additional clinical and molecular studies are warranted to identify biologic and psychosocial risk factors and long-term effects of NOWS. Additionally, access to specialized OUD treatment for pregnant women must be more readily available in the United States, especially in rural areas.

Neurodevelopmental Outcomes of Children Born to Opioid-Dependent Mothers: A Systematic Review and Meta-Analysis

BACKGROUND

Children born to opioid-dependent mothers are at risk of adverse neurodevelopment. The magnitude of this risk remains inconclusive.

OBJECTIVE

To conduct a meta-analysis of studies that assessed neurodevelopmental outcomes of children aged 0 to 12 years born to opioid-dependent mothers, compared with children born to nonopioid-dependent mothers, across general cognitive, language, motor, and social-emotional domains.

DATA SOURCES

PubMed, CINAHL, PsycINFO, and Google Scholar databases.

STUDY ELIGIBILITY CRITERIA

English-language publications between January 1993 and November 2018, including prenatally opioid-exposed and nonopioid-exposed comparison children, reporting outcomes data on standardized assessments.

STUDY APPRAISAL AND SYNTHESIS METHODS

Two reviewers independently extracted data. Pooled standardized mean differences (SMDs) were analyzed using random effects models. Risk of bias was assessed with the Newcastle-Ottawa Quality Assessment Scale.

RESULTS

Across 16 studies, individual domain outcomes data were examined for between 93 to 430 opioid-exposed and 75 to 505 nonopioid-exposed infants/children. Opioid-exposed infants and children performed more poorly than their nonopioid-exposed peers across all outcomes examined, demonstrated by lower infant cognitive (SMD = 0.77) and psychomotor scores (SMD = 0.52), lower general cognition/IQ (SMD = 0.76) and language scores (SMD = 0.65-0.74), and higher parent-rated internalizing (SMD = 0.42), externalizing (SMD = 0.66), and attention problems (SMD = 0.72).

LIMITATIONS

Most studies examined early neurodevelopment; only 3 reported school-age outcomes thereby limiting the ability to assess longer-term impacts of prenatal opioid exposures.

CONCLUSIONS AND IMPLICATIONS OF FINDINGS

Children born to opioid-dependent mothers are at modest- to high-risk of adverse neurodevelopment at least to middle childhood. Future studies should identify specific clinical and social factors underlying these challenges to improve outcomes.

Endogenous opiates and behavior: 2017

This paper is the fortieth consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2017 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).

Neonatal Abstinence Syndrome: Review of Epidemiology, Care Models, and Current Understanding of Outcomes

The incidence of neonatal abstinence syndrome owing to prenatal opioid exposure has grown rapidly in recent decades and it disproportionately affects rural, non-white, and public insurance-dependent populations. Treatment consists of pharmacologic and nonpharmacologic interventions with wide variability in approaches across the United States. Standardizing clinical assessment, minimizing unnecessary interruptions, and prioritizing nonpharmacologic and family-centered care seems to improve hospital outcomes. Neonatal abstinence syndrome may have long-term developmental and biological effects, but understanding is limited owing in part confounding biosocial factors. Early intervention and longitudinal support of the infant and family promote better outcomes.

Racial association and pharmacotherapy in neonatal opioid withdrawal syndrome

OBJECTIVE

To determine if racial differences are associated with Neonatal Opioid Withdrawal Syndrome (NOWS) severity.

STUDY DESIGN

A 10-year (2008-2017) retrospective cohort of infants ≥35 weeks gestation with prenatal exposure to opioids was included. The primary measure was the need for pharmacotherapy. Multivariable logistic regression and propensity score analysis were performed.

RESULTS

Among 345 infants with NOWS, 111 (32%) were black infants with 70% of them requiring pharmacotherapy as compared with 84% of white infants. Upon adjusting for significant covariates (methadone, benzodiazepine use, and gestational age), black infants were 57% less likely than whites to require pharmacotherapy (Odds ratio: 0.43, 95%CI: 0.22-0.80, p = 0.009). Similar results were observed with propensity score analysis.

CONCLUSIONS

Significant racial disparity observed may be secondary to genetic variations in opioid pharmacogenomics and/or extrinsic factors. Large-scale studies are warranted to include race in predictive models for early pharmacological intervention.

Cognitive and Behavioral Impact on Children Exposed to Opioids During Pregnancy

The developmental impact of opioid use during pregnancy is a subject of ongoing debate. Short-term neonatal outcomes, such as lower birth weight and neonatal abstinence syndrome, are the most well-recognized outcomes. However, knowledge gaps exist regarding longer-term neurocognitive and mental health outcomes. In this article, we summarize an expert panel discussion that was held in April 2018 by the Substance Abuse and Mental Health Services Administration and attended by national experts in the field of perinatal opioid exposure and its impact on child development. Despite the challenges with research in this area, there is emerging literature revealing an association between neonates exposed to opioids in utero and longer-term adverse neurocognitive, behavioral, and developmental outcomes. Although adverse sequalae may not be apparent in the neonatal period, they may become more salient as children develop and reach preschool and school age. Multiple variables (genetic, environmental, and biological) result in a highly complex picture. The next steps and strategies to support families impacted by opioid use disorder are explored. Model programs are also considered, including integrated care for the child and mother, parenting supports, and augmentations to home visiting.

The genetics and epigenetics of Neonatal Abstinence Syndrome

Neonatal abstinence syndrome (NAS) due to in-utero opioid exposure is a growing epidemic with significant variability in clinical presentation and severity. Currently, NAS severity cannot be predicted based on clinical factors alone. To date, small studies have identified genetic variants in opioid receptor and stress response genes that are associated with differences in NAS pharmacologic treatment rates and length of hospitalization. In addition, epigenetic variation in the mu opioid receptor (OPRM1) gene has been associated with differences in NAS hospitalization outcomes. Examination of maternal genetic and epigenetic profiles may assist in prediction of NAS severity. Large-scale genomic studies are needed to elucidate the genetic architecture of and epigenetic modification related to NAS in order to develop more tailored personalized treatments for NAS.

Beyond the Finnegan scoring system: Novel assessment and diagnostic techniques for the opioid-exposed infant

Infants with in-utero opioid exposure are most commonly assessed using the Finnegan Neonatal Abstinence Scoring System (FNASS) or a modified version of that tool. Traditionally, the purpose of these tools has been to characterize the extent of withdrawal signs to guide the pharmacologic treatment for infants with neonatal opioid withdrawal syndrome (NOWS). In the past decade however, in response to some of the limitations of the FNASS tool, there has been an increasing emphasis on developing novel assessment tools not based on the FNASS in addition to the promotion of non-pharmacologic treatment options as the first line treatment for infants with opioid exposure. Additionally, several prediction tools that may be useful in determining which patients are at high or low risk for receiving pharmacologic therapy have been developed. In this review, we will evaluate the clinical utility of these novel tools and will consider new avenues for future research.

Analysis of key genes and micro-RNA-mRNA regulatory networks in women with ulcerative interstitial cystitis/pain bladder syndrome

INTRODUCTION AND HYPOTHESIS

This aim of this study was to better understand ulcerative interstitial cystitis/painful bladder syndrome (IC/PBS) at the molecular level and provide new clues related to diagnosis and treatment.

METHODS

The microarray data set GSE11783, including the mRNA and miRNA profiles of bladder tissue obtained at cystoscopic biopsy from patients with ulcerative IC/PBS (presence of at least one Hunner's ulcer) and normal controls, was downloaded from the GEO (Gene Expression Omnibus) database (National Center for Biotechnology Information). These were evaluated using Greenspring GX and Ingenuity Pathway Analysis (IPA) software. The differentially expressed genes (DEGs) and miRNAs (DEMs) in these two groups were identified. Subsequently, the DEGs were subjected to functional analysis, and a protein-protein interaction (PPI) network was constructed. Finally, the miRNA-mRNA regulatory network was visualized using Cystoscope software.

RESULTS

Four DEMs and 1521 DEGs were identified between the ulcerative IC/PBS and control groups. The PPI network of the DEGs was constructed by STRING, which was composed of 393 nodes and 1039 edges, including 221 upregulated genes and 172 downregulated genes. Moreover, 27 genes in the PPI network were identified as hub genes in the IC/PBS group, e.g., PNOC, SSTR1, FPR3, GPR18 and APLNR. Subsequently, 27 clusters were selected from the PPI network using MCODE. It was shown that the most significant cluster consisted of 22 nodes and 231 edges. Moreover, miR-21 was the most significantly upregulated miRNA and was predicted to target one upregulated gene (RASGRP1) and two downregulated genes (KLF5 and SC5D).

CONCLUSIONS

The results of this data mining and integration provide further information on the possible molecular basis of IC/PBS pathogenesis as well as potential biomarkers and therapeutic targets for ulcerative IC/PBS diagnosis and treatment.

Early life stress and environmental influences on the neurodevelopment of children with prenatal opioid exposure

Prenatal opioid exposure has reached epidemic proportions. In the last 10 years, there has been a 242% increase in the number of babies born with the drug withdrawal syndrome known as Neonatal Opioid Withdrawal Syndrome (NOWS). Developmental outcome studies of infants with prenatal opioid exposure are limited by methodological issues including small sample sizes and lack of control for confounding variables such as exposure to poverty and maternal psychopathology. Thus, there is a critical gap in the literature that limits our ability to predict short-term effects of opioid exposure. Here we review direct neurotoxic, indirect, and stress-related pathophysiologies of prenatal opioid exposure. We describe the literature on short and long-term neurodevelopmental outcomes of children with prenatal opioid exposure, highlighting sex differences and the role of early life stress. We conclude by prioritizing avenues for future research for this group of underserved women and their children at risk for neurodevelopmental delays.

Modeling prenatal opioid exposure in animals: Current findings and future directions

The past decade has seen a drastic rise in the number of infants exposed to opioids in utero. It is unclear what lasting effect this exposure may have on these children. Animal models of prenatal opioid exposure may provide insight into potential areas of vulnerability. The present review summarizes the findings across animal models of prenatal opioid exposure, including exposure to morphine, methadone, buprenorphine, and oxycodone. Details regarding the drug, doses, and duration of treatment, as well as key findings, are summarized in tables with associated references. Finally, significant gaps in the current preclinical literature and future directions are discussed.

Suggestions for Model-Informed Precision Dosing to Optimize Neonatal Drug Therapy

Evidence for dosing, efficacy, and safety of most medications used to treat neonates is sparse. Thus, dosing is usually derived by extrapolation from adult and pediatric pharmacologic data with scaling by body weight or body surface area. This may lead to drug dosing that is unsafe or ineffective. However, new strategies are being developed and studied to dose medications in critically ill neonates. Mass spectroscopy technology capable of quickly analyzing drug levels is readily available. Software that integrates population pharmacokinetics and pharmacodynamics with data from sparse samples from neonates allows for timely adjustments of dosing to achieve the desired effect while minimizing adverse outcomes. Some genetic polymorphisms that affect drug response in neonates have also been reported. This review highlights aspects of drug response and how it is impacted by prematurity, assesses pharmacogenomic studies in neonates, and offers suggestions for innovative pharmacokinetic/pharmacodynamic model-based approaches that combine population- or physiology-based pharmacology data, Bayesian analysis, and electronic decision support tools for precision dosing in neonates while illustrating examples where this approach can be used to optimize medical therapy in neonates. Barriers to implementing precision dosing in neonates and how to overcome them are also discussed.

Adult consequences of prenatal drug exposure

Maternal drug use is not new but over the last few decades, the number of mothers using drugs of addiction has escalated to epidemic levels. These drugs are both legal (e.g. prescription medication) and illegal (e.g. heroin) and all will cross the placental barrier into the developing infant. The most immediate and obvious consequence of intra-uterine drug exposure is newborn withdrawal or the Neonatal Abstinence Syndrome (NAS) which is now, with prompt recognition and treatment, an uncommon cause of neonatal death. Thousands (if not millions) of adults most likely would have had a history of passive drug exposure during gestation and the outcomes of these people are unknown. Most are physically healthy and do not need extra medical attention but the effects of prenatal drug exposure may be subtle and extensive. Drug-use disorders are accompanied by a myriad of other adverse problems, including poverty, mental and physical health problems and inadequate parenting ability that may compound the negative effects of drugs. Emerging data suggest that vulnerability to health and neurocognitive issues are pervasive and long-lasting as are lifestyle issues. This review will address current evidence in this area and highlight the knowledge gaps that must be addressed in order to optimise the outcomes for this vulnerable and marginalised but rapidly expanding population of adults.

Will Widespread Synthetic Opioid Consumption Induce Epigenetic Consequences in Future Generations?

A growing number of evidence demonstrates that ancestral exposure to xenobiotics (pollutants, drugs of abuse, etc.) can perturb the physiology and behavior of descendants. Both maternal and paternal transmission of phenotype across generations has been proved, demonstrating that parental drug history may have significant implications for subsequent generations. In the last years, the burden of novel synthetic opioid (NSO) consumption, due to increased medical prescription of pain medications and to easier accessibility of these substances on illegal market, is raising new questions first in term of public health, but also about the consequences of the parental use of these drugs on future generations. Besides being associated to the neonatal abstinence syndrome, in utero exposure to opioids has an impact on neuronal development with long-term repercussions that are potentially transmitted to subsequent generations. In addition, recent reports suggest that opioid use even before conception influences the reactivity to opioids of the progeny and the following generations, likely through epigenetic mechanisms. This review describes the current knowledge about the transgenerational effects of opioid consumption. We summarize the preclinical and clinical findings showing the implications for the subsequent generations of parental exposure to opioids earlier in life. Limitations of the existing data on NSOs and new perspectives of the research are also discussed, as well as clinical and forensic consequences.

Symptoms Associated With Attention Deficit/Hyperactivity Disorder and Autism Spectrum Disorders in School-Aged Children Prenatally Exposed to Substances

Prenatal exposure to substances may influence a child's neurodevelopment and impact on subsequent mental health. In a hospital-based population of school-aged children prenatally exposed to opiates and a number of illicit substances (n = 57), we evaluated mental health symptoms associated with attention deficit/hyperactivity disorder (ADHD) and autism spectrum disorders (ASD) using the Swanson, Nolan, and Pelham Questionnaire, revision IV (SNAP-IV) and the Autism Spectrum Screening Questionnaire (ASSQ) and compared the scores to a reference group which comprised children from the population-based Bergen Child Study (n = 171). Prenatally exposed children had significantly higher SNAP-IV scores associated with ADHD symptoms in both areas of inattention and hyperactivity/impulsivity and also reported a higher ASSQ score related to an increased number of symptoms associated with ASD, compared with the reference group. Of tested predictors of mental health outcomes in the exposed group, the intelligence quotient was a strong predictor of most mental health outcomes, and neonatal abstinence syndrome was a predictor of inattention. In conclusion, prenatally exposed children had more mental health symptoms associated with ADHD and ASD, compared with the reference group.

Neonatal abstinence syndrome: where are we, and where do we go from here?

PURPOSE OF REVIEW

Over the last 15 years the prevalence of neonatal abstinence syndrome (NAS) increased almost five-fold. A considerable diversity seems to prevail in the management of NAS. This review provides an overview of factors affecting the expression and course of NAS, and recent developments in NAS assessment and treatment.

RECENT FINDINGS

Apart from different pharmacological and nonpharmacological treatment modalities, maturity of the infant and genetic variations likely are (co)responsible for interpatient variability in NAS severity, despite similar maternal exposure. Recent efforts concerning the further development of NAS severity scoring systems focus on the development of brief screening measures; in addition, pupil diameter and skin conductance have been proposed as complements to observer-rated scales. The decrease in incidence of NAS begins in the appropriate management of medication assisted treatment of the mother.

SUMMARY

Mitigating the negative outcomes for infants affected by NAS, their mothers and the healthcare system implies, first and foremost, developing and implementing an organized protocol for the management of NAS, and the homogenous use of a standardized scoring system utilizing interobserver reliability and a guide for medication initiation, maintenance, and weaning which is consistent with traditional methods of treatment for neonates.

The Genomics of Neonatal Abstinence Syndrome

Significant variability has been observed in the development and severity of neonatal abstinence syndrome (NAS) among neonates exposed to prenatal opioids. Since maternal opioid dose does not appear to correlate directly with neonatal outcome, maternal, placental, and fetal genomic variants may play important roles in NAS. Previous studies in small cohorts have demonstrated associations of variants in maternal and infant genes that encode the μ-opioid receptor (OPRM1), catechol-O-methyltransferase (COMT), and prepronociceptin (PNOC) with a shorter length of hospital stay and less need for treatment in neonates exposed to opioids in utero. Consistently falling genomic sequencing costs and computational approaches to predict variant function will permit unbiased discovery of genomic variants and gene pathways associated with differences in maternal and fetal opioid pharmacokinetics and pharmacodynamics and with placental opioid transport and metabolism. Discovery of pathogenic variants should permit better delineation of the risk of developing more severe forms of NAS. This review provides a summary of the current role of genomic factors in the development of NAS and suggests strategies for further genomic discovery.