Opioids and the developing brain: time to rethink perinatal care for infants of opioid-dependent mothers

Children had smaller brain volumes and cortical surface areas after prenatal opioid maintenance therapy exposure

AIM

The studies have shown that infants with prenatal OMT exposure had smaller brain volumes than non-exposed controls, but long-term outcome data are lacking. We examined 5-13-year-old OMT-exposed children with brain MRI and tested motor and visual-motor functions and possible associations between brain morphology and outcome.

METHODS

To this retrospective cohort study, we recruited 55 children with prenatal OMT exposure and 59 age- and gender-matched controls. They were examined with brain MRI, Movement-ABC and Beery-VMI. MRI images were processed with the Free Surfer® software to obtain volumetrics and estimates of cortical surface area and thickness. We used a general linear regression model (GLM) to calculate group differences.

RESULTS

The children in the OMT group had smaller mean total intracranial volume (ICV), 1407 cm3 (CI 95% 1379-1434) versus 1450 cm3 (CI 95% 1423-1476) in the control group (p = 0.026). After adjusting for ICV, significant group differences persisted for volumes of amygdala, basal ganglia and mid-posterior part of corpus callosum. Cortical surface area was smaller in the left caudal middle frontal gyrus and the right inferior parietal lobule in the OMT-group. Visual-motor function was significantly correlated with ICV.

CONCLUSION

Prenatal OMT exposure may alter early brain development with possible negative long-term functional consequences.

Developmental Outcomes after Opioid Exposure in the Fetus and Neonate

The overall prevalence of opiate use has been increasing, currently affecting approximately 0.6% of the global population and resulting in a significant proportion of infants being born with prenatal opioid exposure. Animal and human models of prenatal opioid exposure demonstrate detrimental effects on brain anatomy as well as neurodevelopment. Less is known about the neurologic sequelae of postnatal opioid exposure in hospitalized infants. In this review, we summarize our current understanding of the impact of prenatal and postnatal opioid exposure on the brain and on neurodevelopment outcomes. We also identify resources and management strategies that may help mitigate neurodevelopmental delays and deficits associated with opioid exposure in this vulnerable population.

Treatment for Neonatal Abstinence Syndrome using Nonpharmacological Interventions

OBJECTIVE

 Management of neonatal abstinence syndrome includes nonpharmacological interventions, but their effectiveness may not be verified before implemented. The objective of this study is to evaluate the effectiveness of a type of bassinet in the treatment of infants with neonatal abstinence syndrome.

STUDY DESIGN

 This is a retrospective observational cohort study. Study setting involved a 24-bed open-bay Level III neonatal intensive care unit located in a metropolitan academic trauma facility. Participant inclusion criteria involved prenatally opioid-exposed infants ≥ 35 weeks with confirmed maternal opioid urine toxicology, required pharmacological treatment for withdrawal symptoms, and were admitted to the neonatal intensive care unit. Three subsets of study participants were analyzed over three different time periods: Group 1 were infants admitted during 2019 without nonpharmacological intervention, Group 2 who were admitted from September 2021 to February 2022 and received nonpharmacological interventions, and Group 3 included those admitted from February 2022 to March 2023 who received the same interventions as Group 2 but were managed in bassinets being used in other local facilities for neonatal abstinence syndrome.

RESULTS

 Group 3 had significant increases in length of stay compared with Group 1 (p = 0.006) and Group 2 (p = 0.013). Group 3 had a significantly greater length of treatment than Group 1 (p = 0.041) and a significantly higher total mg/kg morphine exposure than Group 1 (p = 0.006).

CONCLUSION

 Addition of the bassinet for nonpharmacological management of infants with neonatal abstinence syndrome appeared to prolong length of stay, length of treatment, and increase total mg/kg morphine exposure. As a retrospective nonrandomized study, weakness of low certainty of causality is of concern but findings strongly warrant further research before devices such as the bassinet used in this study are adopted for routine neonatal abstinence syndrome care.

KEY POINTS

· Special bassinets are promoted to enhance sleep and decrease agitation.. · Such bassinets may assist infants undergoing drug withdrawal.. · Study of the bassinet failed to show benefit to this population..

Antenatal care of women who use opioids: a qualitative study of practitioners' perceptions of strengths and challenges of current service provision in Scotland

BACKGROUND

The increasing rise of women using opioids during pregnancy across the world has warranted concern over the access and quality of antenatal care received by this group. Scotland has particularly high levels of opioid use, and correspondingly, pregnancies involving women who use opioids. The purpose of this study was to investigate the different models of antenatal care for women using opioids during pregnancy in three Scottish Health Board Areas, and to explore multi-disciplinary practitioners' perceptions of the strengths and challenges of working with women who use opioids through these specialist services.

METHODS

Thirteen semi-structured interviews were conducted with health and social care workers who had experience of providing antenatal and postnatal care to women who use drugs across three Scottish Health Board Areas: NHS Greater Glasgow and Clyde, NHS Lothian, and NHS Tayside. Framework Analysis was used to analyse interview data. The five stages of framework analysis were undertaken: familiarisation, identifying the thematic framework, indexing, charting, and mapping and interpretation.

RESULTS

Each area had a specialist antenatal pathway for women who used substances. Pathways varied, with some consisting of specialist midwives, and others comprising a multidisciplinary team (e.g. midwife, mental health nurse, social workers, and an obstetrician). Referral criteria for the specialist service differed between health board areas. These specialised pathways presented several key strengths: continuity of care with one midwife and a strong patient-practitioner relationship; increased number of appointments, support and scans; and highly specialised healthcare professionals with experience of working with substance use. In spite of this, there were a number of limitations to these pathways: a lack of additional psychological support for the mother; some staff not having the skills to engage with the complexity of patients who use substances; and problems with patient engagement.

CONCLUSIONS

Across the three areas, there appears to be high-quality multi-disciplinary antenatal services for women who use opioids during pregnancy. However, referral criteria vary and some services appear more comprehensive than others. Further research is needed into the perceptions of women who use opioids on facilitators and barriers to antenatal care, and provision in rural regions of Scotland.

Impaired vision in children prenatally exposed to methadone: an observational cohort study

BACKGROUND/OBJECTIVES

To examine prevalence of failed visual assessment at 8-10 years in children born to methadone-maintained opioid dependent (MMOD) mothers and relate this to known in utero substance exposure.

SUBJECTS/METHODS

Follow up of observational cohort study of methadone-exposed and comparison children matched for birthweight, gestation and postcode of residence at birth. Participants were 144 children (98 exposed, 46 comparison). Prenatal drug exposure was previously established via comprehensive maternal and neonatal toxicology. Children were invited to attend for visual assessment and casenotes were reviewed. Presence of acuity poorer than 0.2 logMAR, strabismus, nystagmus and/or impaired stereovision constituted a 'fail'. Fail rates were compared between methadone-exposed and comparison children after adjusting for known confounding variables.

RESULTS

33 children attended in person: data were also derived from casenote review for all children. After controlling for maternal reported tobacco use, methadone-exposed children were more likely to have a visual 'fail' outcome, adjusted odds ratio 2.6, 95% CI 1.1-6.2; adjusted relative risk 1.8 (95% CI 1.1-3.4). Visual 'fail' outcome rates did not differ between methadone-exposed children who had (n = 47) or had not (n = 51) received pharmacological treatment for neonatal abstinence/opioid withdrawal syndrome (NAS/NOWS); fail rate 62% vs 53% (95% CI of difference-11-27%).

CONCLUSIONS

Children born to MMOD mothers are almost twice as likely as unexposed peers to have significant visual abnormalities at primary school age. Prenatal methadone exposure should be considered in the differential diagnosis of nystagmus. Findings support visual assessment prior to school entry for children with any history of prenatal opioid exposure.

TRIAL REGISTRATION

The study was prospectively registered on ClinicalTrials.gov (NCT03603301), https://clinicaltrials.gov/ct2/show/NCT03603301 .

In utero methadone exposure permanently alters anatomical and functional connectivity: A preclinical evaluation

The opioid epidemic is an ongoing public health crisis, and children born following prenatal opioid exposure (POE) have increased risk of long-term cognitive and behavioral sequelae. Clinical studies have identified reduced gray matter volume and abnormal white matter microstructure in children with POE but impacts on whole-brain functional brain connectivity (FC) have not been reported. To define effects of POE on whole brain FC and white matter injury in adult animals, we performed quantitative whole-brain structural and functional MRI. We used an established rat model of POE in which we have previously reported impaired executive function in adult rats analogous to persistent neurocognitive symptoms described in humans with POE. Pregnant Sprague-Dawley rat dams received continuous methadone (12 mg/kg/day) vs. saline infusion for 28 days via osmotic mini-pumps, exposing rats to pre- and postnatal opioid until weaning. At young adult age (P60), POE and saline exposed offspring underwent in vivo MRI included diffusion tensor imaging and functional MRI (fMRI). Results indicate that fractional anisotropy (FA) was decreased in adult animals with POE [n = 11] compared to animals that received saline [n = 9] in major white matter tracts, including the corpus callosum (p < 0.001) and external capsule (p < 0.01). This change in FA was concomitant with reduced axial diffusivity in the external capsule (p < 0.01) and increased radial diffusivity in the corpus callosum (p < 0.01). fMRI analyses reveal brainwide FC was diffusely lower in POE (p < 10-6; 10% of variance explained by group). Decreased connectivity in cortical-cortical and cortico-basal ganglia circuitry was particularly prominent with large effect sizes (Glass's Δ > 1). Taken together, these data confirm POE reduces brainwide functional connectivity as well as microstructural integrity of major white matter tracts. Altered neural circuitry, dysregulated network refinement, and diffuse network dysfunction have been implicated in executive function deficits that are common in children with POE. FC may serve as a translatable biomarker in children with POE.

Future Newborns with Opioid-Induced Neonatal Abstinence Syndrome (NAS) Could Be Assessed with the Genetic Addiction Risk Severity (GARS) Test and Potentially Treated Using Precision Amino-Acid Enkephalinase Inhibition Therapy (KB220) as a Frontline Modality Instead of Potent Opioids

In this nonsystematic review and opinion, including articles primarily selected from PubMed, we examine the pharmacological and nonpharmacological treatments of neonatal abstinence syndrome (NAS) in order to craft a reasonable opinion to help forge a paradigm shift in the treatment and prevention of primarily opioid-induced NAS. Newborns of individuals who use illicit and licit substances during pregnancy are at risk for withdrawal, also known as NAS. In the US, the reported prevalence of NAS has increased from 4.0 per 1000 hospital births in 2010 to 7.3 per 1000 hospital births in 2017, which is an 82% increase. The management of NAS is varied and involves a combination of nonpharmacologic and pharmacologic therapy. The preferred first-line pharmacological treatment for NAS is opioid therapy, specifically morphine, and the goal is the short-term improvement in NAS symptomatology. Nonpharmacological therapies are individualized and typically focus on general care measures, the newborn-parent/caregiver relationship, the environment, and feeding. When used appropriately, nonpharmacologic therapies can help newborns with NAS avoid or reduce the amount of pharmacologic therapy required and the length of hospitalization. In addition, genetic polymorphisms of the catechol-o-methyltransferase (COMT) and mu-opioid receptor (OPRM1) genes appear to affect the length of stay and the need for pharmacotherapy in newborns with prenatal opioid exposure. Therefore, based on this extensive literature and additional research, this team of coauthors suggests that, in the future, in addition to the current nonpharmacological therapies, patients with opioid-induced NAS should undergo genetic assessment (i.e., the genetic addiction risk severity (GARS) test), which can subsequently be used to guide DNA-directed precision amino-acid enkephalinase inhibition (KB220) therapy as a frontline modality instead of potent opioids.

Assessing the Impact of Prenatal Medication for Opioid Use Disorder on Discharge Home With Parents Among Infants With Neonatal Opioid Withdrawal Syndrome

OBJECTIVES

The number of women with opioid-related diagnoses in the United States has significantly increased in recent decades, resulting in concomitantly higher rates of infants born with neonatal opioid withdrawal syndrome (NOWS). Addressing prenatal opioid exposure is a priority for Alaska health systems. The objectives of this study were to: (1) identify maternal and neonatal factors associated with receipt of Medication for opioid use disorder (MOUD) and (2) determine the impact of prenatal MOUD on discharge to parents among infants with NOWS in 3 Alaska hospitals.

METHODS

A retrospective chart review using a standard abstraction form was conducted to collect data on neonatal and maternal characteristics, neonatal treatment, and infant discharge disposition for infants with NOWS born at the 3 hospitals between July 2016 and December 2019. A multivariable logistic regression model was used to determine factors associated with discharge to parents.

RESULTS

There were 10,719 births at the 3 hospitals during the study period, including 193 infants (1.8%) with NOWS. Among the 193 mothers, 91 (47.2%) received MOUD during pregnancy. Among infants with NOWS, 136 (70.5%) were discharged to parents, 51 (26.4%) were discharged to a relative or foster care. Infants were significantly (odds ratio 3.9) more likely to be discharged to parents if the mother had received prenatal MOUD.

CONCLUSIONS

MOUD among pregnant women with opioid use disorder furthers the goal of keeping families together and is a critical step towards reducing the impact of the ongoing opioid epidemic on Alaska families, communities, and the child welfare system.