Ophthalmic, clinical and visual electrophysiological findings in children born to mothers prescribed substitute methadone in pregnancy

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 .

Long-Term Visual and Neurodevelopmental Outcomes in Two Children with Congenital Nystagmus Secondary to Methadone Exposure In utero

Methadone is used as a substitute for illicit opioids during pregnancy. However, the real effect of this molecule on visual and neurodevelopmental outcomes of the children exposed is not fully understood, since studies considered subjects born to polydrug-dependent mothers and followed for few months/years. We report the long-term outcomes of two infants with congenital nystagmus solely exposed to methadone in utero. Neurological and neurovisual evaluations were performed every year from the first year of life to 11 years of age. One child was diagnosed with developmental coordination disorder. Both cases presented with ophthalmologic (refractive errors), oculomotor (nystagmus and fixation, smooth pursuit, and saccades dysfunctions), and perceptive problems (reduced visual acuity and contrast sensitivity). While nystagmus and other oculomotor dysfunctions remained stable over time, visual acuity and contrast sensitivity improved; refractive errors worsened and required corrective lenses. Both children showed normal neurodevelopmental and cognitive profile. This report highlights the long-term visual and developmental outcomes of two children exclusively exposed to methadone underlining the possibility of a visual dysfunction and motor coordination disorder. These observations prompt the need to investigate prenatal drug exposure as a cause of congenital nystagmus.

Harmful effects of opioid use in pregnancy: A scientific review commissioned by the European Board and College of obstetrics and gynaecology (EBCOG)

Caring for pregnant women who have a recreational opioid use disorder is a common clinical challenge in modern obstetric care. These are an elusive population who often have multiple social issues that complicate their pregnancy management. Comprehensive and supportive maternal care can motivate these mothers to change her lifestyle. Multidisciplinary non-judgemental approach with appropriate medication and management, can result in good pregnancy outcomes for mother and her baby.

Otolaryngologic conditions in children with neonatal abstinence syndrome: A descriptive study

PURPOSE

Literature on otolaryngologic sequelae of children with neonatal abstinence syndrome (NAS) has been scarce to date. Prior reports suggest some otologic conditions associated with long-term NAS outcomes, but no comprehensive exploration of these relationships currently exists. This study aims to characterize the breadth of otolaryngologic conditions diagnosed in children with NAS.

METHODS

This is a retrospective descriptive study conducted at a tertiary care hospital. We identified 524 children with NAS born between 1/1/2014 and 12/31/2019 who were evaluated by the otolaryngology department. Diagnoses were categorized as otologic, oropharyngeal, sinonasal, and laryngeal. Additional diagnoses of obstructive sleep apnea (OSA) and congenital abnormalities of head and neck were noted separately. Descriptive statistics were calculated, and ANCOVA testing analyzed for differences in mean number of diagnoses.

RESULTS

680 total otolaryngologic diagnoses were analyzed across 524 patients. Otologic conditions comprised 39.7 % of total diagnoses, oropharyngeal conditions 26.8 %, sinonasal conditions 18.4 %, laryngeal conditions 5.3 %, OSA 1.5 %, and congenital abnormalities 8.3 %. After adjusting for covariates, there were a significantly higher number of otologic diagnoses compared to the other subcategories with mean (standard deviation) of 0.46 (0.83), followed by oropharyngeal 0.35 (0.55), sinonasal 0.24 (0.49), and laryngeal 0.07 (0.29). Thirty total otolaryngology-related procedures were performed in our sample, with myringotomy with tube insertion as the most common.

CONCLUSION

Understanding the otolaryngologic sequelae of children with NAS is important as these conditions impact children's early development. Our study also highlights various socioeconomic factors that may impact pediatric ENT care and the follow-up of patients born with NAS.

TFOS Lifestyle: Impact of lifestyle challenges on the ocular surface

Many factors in the domains of mental, physical, and social health have been associated with various ocular surface diseases, with most of the focus centered on aspects of dry eye disease (DED). Regarding mental health factors, several cross-sectional studies have noted associations between depression and anxiety, and medications used to treat these disorders, and DED symptoms. Sleep disorders (both involving quality and quantity of sleep) have also been associated with DED symptoms. Under the domain of physical health, several factors have been linked to meibomian gland abnormalities, including obesity and face mask wear. Cross-sectional studies have also linked chronic pain conditions, specifically migraine, chronic pain syndrome and fibromyalgia, to DED, principally focusing on DED symptoms. A systematic review and meta-analysis reviewed available data and concluded that various chronic pain conditions increased the risk of DED (variably defined), with odds ratios ranging from 1.60 to 2.16. However, heterogeneity was noted, highlighting the need for additional studies examining the impact of chronic pain on DED signs and subtype (evaporative versus aqueous deficient). With respect to societal factors, tobacco use has been most closely linked to tear instability, cocaine to decreased corneal sensitivity, and alcohol to tear film disturbances and DED symptoms.

Neonatal Opioid Withdrawal Syndrome: An Update on Developmental Outcomes

Infants and children with prenatal opioid exposure generally have development within the normal range; however, they seem to be at risk for behavioral problems and for lower scores on cognitive, language, and motor assessments than children without prenatal opioid exposure. It is as of yet unclear whether prenatal opioid exposure itself causes issues with development and behavior, or whether it is simply correlated, due to other confounding factors.

Comparison of Ocular and Brain Abnormalities Among Neonates With In Utero Exposure to Opium or Other Drugs

Background

There are growing concerns regarding ocular and brain abnormalities in infants who had in utero exposure to various kinds of substances/drugs. We compared the ocular and brain abnormalities among neonates based on the type of drug used by mothers.

Methodology

This prospective cohort study of 305 neonates included all neonates at Mahdieh Hospital, Tehran, Iran, who had their records for ophthalmic screening and brain sonography and were born to mothers with a history of substance use disorder (2014-2017). Demographic data, results for viral antibodies (human immunodeficiency virus, hepatitis C, and hepatitis B), and Apgar scores at one and five minutes were collected. We excluded neonates with Apgar score <8 at one minute, weight <1,800 g, gestational age <35 weeks, asphyxia, or anomalies. The neonates’ eyes were examined using tropicamide 0.5%, phenylephrine 2.5%, and tetracaine.

Results

The prevalence of substance use disorder among pregnant women was 1.8%. The study included 305 neonates with a mean gestational age of 37.8 ± 1.6 weeks, while the mean age of their mothers with substance use disorder was 29.8 ± 6.4 years. Ophthalmologic examination showed that 37 (12%) neonates had abnormal incomplete retina vascularization, and brain abnormalities were seen in 29 (9.5%) neonates; however, no difference was identified based on the type of drug used by mothers. The birth weight (BW) of the neonates depended on the type of drugs used by the mothers (p = 0.027). Maternal use of cannabis and amphetamine were associated with the lowest and highest BWs (2,800 ± 283 and 3,750 ± 42 g), respectively.

Conclusions

The BW of neonates depended on the type of drugs used by the mothers, where cannabis and amphetamine use were associated with the lowest and highest BWs, respectively. However, our data could not identify if neonates’ ocular and brain abnormalities differed based on the types of drugs. This study highlights the importance of a drug-free pregnancy and the need for addiction-prevention programs provided to women of childbearing age.

The Multidisciplinary Guidelines for Diagnosis and Referral in Cerebral Visual Impairment

Introduction

Cerebral visual impairment (CVI) is an important cause of visual impairment in western countries. Perinatal hypoxic-ischemic damage is the most frequent cause of CVI but CVI can also be the result of a genetic disorder. The majority of children with CVI have cerebral palsy and/or developmental delay. Early diagnosis is crucial; however, there is a need for consensus on evidence based diagnostic tools and referral criteria. The aim of this study is to develop guidelines for diagnosis and referral in CVI according to the grade method.

Patients and Methods

We developed the guidelines according to the GRADE method 5 searches on CVI (children, developmental age ≤ 18 years) were performed in the databases Medline, Embase, and Psychinfo, each with a distinct topic.

Results

Based on evidence articles were selected on five topics: 1. Medical history and CVI-questionnaires 23 (out of 1,007). 2. Ophthalmological and orthoptic assessment 37 (out of 816). 3. Neuropsychological assessment 5 (out of 716). 4. Neuroradiological evaluation and magnetic resonance imaging (MRI) 9 (out of 723). 5. Genetic assessment 5 (out of 458).

Conclusion

In medical history taking, prematurity low birth weight and APGAR (Appearance, Pulse, Grimace, Activity, Respiration) Scores (<5) are important. Different questionnaires are advised for children under the age of 3 years, older children and for specific risk groups (extremely preterm). In ophthalmological examination, eye movements, specially saccades, accommodation, crowding, contrast sensitivity and visual fields should be evaluated. OCT can show objective signs of trans-synaptic degeneration and abnormalities in fixation and saccades can be measured with eye tracking. Screening of visual perceptive functioning is recommended and can be directive for further assessment. MRI findings in CVI in Cerebral Palsy can be structured in five groups: Brain maldevelopment, white and gray matter lesions, postnatal lesions and a normal MRI. In children with CVI and periventricular leukomalacia, brain lesion severity correlates with visual function impairment. A differentiation can be made between cortical and subcortical damage and related visual function impairment. Additional assessments (neurological or genetic) can be necessary to complete the diagnosis of CVI and/or to reveal the etiology.

Ophthalmic outcomes in children exposed to opioid maintenance treatment in utero: A systematic review and meta-analysis

Opioid use disorder is a significant global issue and the rate of opioid use in women of childbearing age and pregnant women is on the rise. Whilst the adverse general health, cognitive, and neurodevelopmental outcomes of in utero exposure to opioids have been explored, there is a lack of prospective, controlled, longitudinal research into the ophthalmic outcomes. Existing research suggests that there is an association between prenatal exposure and future risk of abnormalities in visual functioning. This systematic review and meta-analysis analysed studies that measured eye abnormalities in infants or children exposed to opioid maintenance therapy in utero and compared them to non-opioid exposed controls. After considering the clinical findings, limitations of the studies, confounding factors, and quantitative analysis, a causal relationship between in utero opioid exposure and future eye abnormalities could not be confirmed. The implications of the findings and their clinical relevance, in addition to identified gaps for future research are also discussed in this paper.

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

Illicit use of opioids is a global health crisis with major implications for women and children. Strategies for managing opioid use disorder (OUD) in pregnancy have been tested over the past 40 years, but studies have focused on maternal and pregnancy outcomes, with less attention given to long-term follow-up of exposed children. Here, we provide a narrative review of recent advances in the assessment and management of neonatal opioid withdrawal syndrome (NOWS), and we summarise evidence from multiple domains-neuroimaging, electrophysiology, visual development and function, neurodevelopment, behaviour, cognition and education-which suggests that prenatal opioid exposure modifies child development. Further studies are required to determine the optimal management of pregnant women with OUD and babies with NOWS. We identify knowledge gaps and suggest that future study designs should evaluate childhood outcomes, including infant brain development and long-term neurocognitive and visual function.

Prenatal opioid exposure is associated with smaller brain volumes in multiple regions

BACKGROUND

The impact of prenatal opioid exposure on brain development remains poorly understood.

METHODS

We conducted a prospective study of term-born infants with and without prenatal opioid exposure. Structural brain MRI was performed between 40 and 48 weeks postmenstrual age. T2-weighted images were processed using the Developing Human Connectome Project structural pipeline. We compared 63 relative regional brain volumes between groups.

RESULTS

Twenty-nine infants with prenatal opioid exposure and 42 unexposed controls were included. The groups had similar demographics, except exposed infants had lower birth weights, more maternal smoking and maternal Hepatitis C, fewer mothers with a college degree, and were more likely non-Hispanic White. After controlling for sex, postmenstrual age at scan, birth weight, and maternal education, exposed infants had significantly smaller relative volumes of the deep gray matter, bilateral thalamic ventrolateral nuclei, bilateral insular white matter, bilateral subthalamic nuclei, brainstem, and cerebrospinal fluid. Exposed infants had larger relative volumes of the right cingulate gyrus white matter and left occipital lobe white matter.

CONCLUSIONS

Infants with prenatal opioid exposure had smaller brain volumes in multiple regions compared to controls, with two regions larger in the opioid-exposed group. Further research should focus on the relative contributions of maternal opioids and other exposures.

IMPACT

Prenatal opioid exposure is associated with developmental and behavioral consequences, but the direct effects of opioids on the developing human brain are poorly understood. Prior small studies using MRI have shown smaller regional brain volumes in opioid-exposed infants and children. After controlling for covariates, infants with prenatal opioid exposure scanned at 40-48 weeks postmenstrual age had smaller brain volumes in multiple regions compared to controls, with two regions larger in the opioid-exposed group. This adds to the literature showing potential impact of prenatal opioid exposure on the developing brain.

Lasting effects of prenatal exposure to Cannabis in the retina of the offspring: an experimental study in mice

Background

Prenatal exposure to Cannabis is a worldwide growing problem. Although retina is part of the central nervous system, the impact of maternal Cannabis use on the retinal development and its postnatal consequences remains unknown. As the prenatal period is potentially sensitive in the normal development of the retina, we hypothesized that recreational use of Cannabis during pregnancy may alter retina structure in the offspring. To test this, we developed a murine model that mimics human exposure in terms of dose and use.

Methods

Pregnant BalbC mice were exposed daily for 5 min to Cannabis smoke (0.2 g of Cannabis) or filtered air, from gestational day 5 to 18 (N = 10/group). After weaning period, pups were separated and examined weekly. On days 60, 120, 200, and 360 after birth, 10 pups from each group were randomly selected for Spectral Domain Optical Coherence Tomography (SD-OCT) analysis of the retina. All retina layers were measured and inner, outer, and total retina thickness were calculated. Other 37 mice from both groups were sacrificed on days 20, 60, and 360 for retinal stereology (total volume of the retina and volume fraction of each retinal layer) and light microscopy. Means and standard deviations were calculated and MANOVA was performed.

Results

The retina of animals which mother was exposed to Cannabis during gestation was 17% thinner on day 120 (young adult) than controls (P = 0.003) due to 21% thinning of the outer retina (P = 0.001). The offspring of mice from the exposed group presented thickening of the IS/OS in comparison to controls on day 200 (P < 0.001). In the volumetric analyzes by retinal stereology, the exposed mice presented transitory increase of the IS/OS total volume and volume fraction on day 60 (young adult) compared to controls (P = 0.008 and P = 0.035, respectively). On light microscopy, exposed mice presented thickening of the IS/OS on day 360 (adult) compared to controls (P = 0.03).

Conclusion

Gestational exposure to Cannabis smoke may cause structural changes in the retina of the offspring that return to normal on mice adulthood. These experimental evidences suggest that children and young adults whose mothers smoked Cannabis during pregnancy may require earlier and more frequent clinical care than the non-exposed population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40942-021-00314-8.

Impact of Prenatal Exposure to Opioids, Cocaine, and Cannabis on Eye Disorders in Children

OBJECTIVES

Prenatal substance exposure is associated with abnormal visual evoked potentials in offspring, but whether ocular abnormalities are present past infancy is unclear. We determined the association between prenatal substance exposure and hospitalizations for eye disorders in childhood.

METHODS

We conducted a longitudinal cohort study of 794,099 infants born between 2006 and 2016 in all hospital centers in Quebec, Canada. We identified infants prenatally exposed to opioids, cocaine, cannabis, and other illicit substances and followed them over time to assess eye disorders that required in-hospital treatment, including retinal detachment and breaks, strabismus, and other ocular pathologies. We calculated incidence rates and hazard ratios (HR) with 95% confidence intervals (CI) for the association of prenatal substance exposure with risk of eye disorders, adjusted for patient characteristics.

RESULTS

Infants exposed to substances prenatally had a higher incidence of hospitalizations for eye disorders compared with unexposed infants (47.0 vs 32.0 per 10,000 person-years). Prenatal substance exposure was associated with 1.23 times the risk of hospital admission for any eye disorder during childhood compared with no exposure (95% CI 1.04-1.45). Risks were greatest for strabismus (HR 1.55, 95% CI 1.16-2.07) and binocular movement disorders (HR 1.96, 95% CI 1.00-3.83). Opioid use was strongly associated with the risk of ocular muscle disorders (HR 3.15, 95% CI 1.98-5.01).

CONCLUSIONS

Prenatal substance exposure is significantly associated with future hospitalizations for eye disorders in childhood. Efforts to minimize substance use in women of reproductive age are needed in light of the current opioid epidemic.

Neonatal sleep development and early learning in infants with prenatal opioid exposure

The aim of this chapter is to examine the role of sleep and cognition in the context of the cumulative risk model examining samples of at-risk infants and maternal-infant dyads. The cumulative risk model posits that non-optimal developmental outcomes are the result of multiple factors in a child's life including, but not limited to, prenatal teratogenic exposures, premature birth, family socioeconomic status, parenting style and cognitions as well as the focus of this volume, sleep. We highlight poor neonatal sleep as both an outcome of perinatal risk as well as a risk factor to developing attentional and cognitive capabilities during early childhood. Outcomes associated with and contributing to poor sleep and cognition during infancy are examined in relation to other known risks in our clinical population. Implications of this research and recommendations for interventions for this population are provided.

Longitudinal Outcomes of Children Exposed to Opioids In-utero: A Systematic Review

PURPOSE

The purpose was to summarize evidence of long-term outcomes of children, 2 years and older, exposed to opioids in-utero.

DESIGN

This was a systematic review. Studies were identified by searching the following electronic databases: PubMed, EBSCO HOST/Medline, and Web of Science. Articles were published between 1979 and 2019.

METHODS

This systematic review was reported according to the Preferred Reporting Items for Systematic Review and Meta-Analysis. Two sets of two independent reviewers extracted data and assessed study quality according to National Institutes of Health quality assessment tools.

RESULTS

Forty-three articles met inclusion criteria. Synthesis of articles identified trends toward worse outcomes for children with in-utero opioid exposure in all areas, most notably related to academic success, behavior, cognition, hospitalizations, and vision.

CONCLUSIONS

Findings reinforce the necessity of continued research in this area with improved study design. Despite limitations in the current body of evidence, findings from this review are vital knowledge for clinicians, because children exposed to opioids in-utero are clearly vulnerable to a wide variety of suboptimal health and developmental outcomes.

CLINICAL RELEVANCE

Recognition of all outcomes across childhood associated with in-utero opioid exposure will inform improved identification and interventions tailored to the most pressing needs of affected children. Despite the need for continued research, there is sufficient evidence to necessitate close, individualized follow-up throughout childhood.

Childhood Health and Educational Outcomes After Neonatal Abstinence Syndrome: A Systematic Review and Meta-analysis

OBJECTIVE

To systematically review and meta-analyze the association between neonatal abstinence syndrome (NAS) and adverse health or educational childhood outcomes.

STUDY DESIGN

An all-language search was conducted across 11 databases between January 1, 1975, and September 3, 2019; 5865 titles were identified. Observational studies of children between 28 days and 16 years of age, in whom a diagnosis of NAS was documented, were included. Outcomes included reasons for hospital admissions, childhood diagnoses, developmental outcomes, and academic attainment scores. All studies underwent independent review by 2 trained reviewers, who extracted study data and assessed risk of bias using the Newcastle Ottawa Tool.

RESULTS

Fifteen studies were identified that included 10 907 children with previous NAS and 1 730 213 children without previous NAS, aged 0-16 years. There was a strong association between NAS and subsequent child maltreatment (aOR, 6.49; 95% CI, 4.46-9.45; I² = 52%), injuries and poisoning (aOR, 1.34; 95% CI, 1.21-1.49; I² = 0%), and a variety of mental health conditions. Studies consistently demonstrated an increased incidence of strabismus and nystagmus among those with previous NAS. Children with NAS also had lower mean academic scores than the control group in every domain of testing across age groups.

CONCLUSIONS

NAS is significantly associated with future child maltreatment, mental health diagnoses, visual problems, and poor school performance. Owing to the necessary inclusion of nonrandomized studies, incomplete reporting among studies, and likely unadjusted confounding, this review does not suggest causation. However, we highlight associations requiring further investigation and targeted intervention, to positively impact the life course trajectories of this growing population of children.

Prenatal opioid exposure - Increasing evidence of harm

Prenatal opioid exposure adversely impacts upon fetal growth and places the newborn at risk of neonatal opioid withdrawal. The severity and duration of opioid withdrawal cannot be predicted in the individual baby and may be contributed to by other drugs including benzodiazepines and alcohol as well as cigarette smoking. Mitigating factors include breastfeeding, rooming in and absence of maternal polypharmacy. Less well recognised are a variety of other complications associated with prenatal opioid exposure including epigenetic changes, effects on neurophysiological function and structural alterations to the developing brain. The visual system is significantly affected, with changes to both clinical and electrophysiological function persisting at least to mid-childhood. Longer term neurodevelopmental and behavioural outcomes are confounded by multiple factors including poverty, parent-child interaction and small study numbers, but systematic reviews consistently demonstrate poorer outcomes for those children and young people prenatally exposed to opioids. Crucially, manifestation of neonatal withdrawal is not a prerequisite for important long term problems including behavioural, emotional or motor function disorder, sensory or speech disorder, strabismus and nystagmus. A body of evidence supports an independent adverse effect of prenatal opioid exposure upon fetal brain development, mediated via a systemic neuro-inflammatory process. Children prenatally exposed to opioids should remain under appropriate follow up, at least until school entry, as difficulties may only become apparent in mid-childhood. Future studies of the management of opioid use disorder in pregnancy, including maintenance methadone, must include longer term outcomes for the baby.

Congenital Nystagmus and Its Congeners

In recent years, we have made enormous strides in elucidating the phenomenology of congenital nystagmus. The purpose of this review is to briefly summarize our current understanding of congenital nystagmus in terms of its clinical symptomatology, pathophysiology, differential diagnosis, and ancillary testing, and clinical management. Finally, this discussion provides the reader with an armamentarium of clinical pearls to facilitate diagnosis of the numerous sensory visual disorders that can underlie congenital nystagmus.

Strabismus Patterns in Patients with Intrauterine Drug Exposure

Purpose: This retrospective study evaluates the patterns of strabismus, the incidence of amblyopia, and prevalence of anatomical ocular pathology in patients with intrauterine drug exposure (IDE) presenting to a tertiary referral center for an ophthalmic evaluation.Methods: We reviewed charts of patients who presented to our pediatric ophthalmology clinic from 8/2017-10/2018 with reported IDE. The mean age at presentation was 29 months. We documented the type of exposure, birth history, social history, and past medical and surgical history. Visual acuity, motility, fundus exam, and cycloplegic refraction were reviewed.Results: Thirty-eight patients met the criteria. Motility exam showed that 23 patients were exotropic, 10 were esotropic, and 5 were orthophoric. Average angle of the exotropic deviation was 27ΔXT (range X 10 to XT 50). Amblyopia, nystagmus, and anatomical ocular anomalies also occurred frequently.Conclusion: Strabismus and other eye diseases are common in patients with IDE. Exodeviations were the most common finding and occurred in 60.5% of our cohort. Patients with IDE are at a higher risk for treatable conditions such as strabismus and amblyopia. Possible history of IDE should be considered in infants who present with congenital strabismus, particularly exotropia.

Effects of cannabis and its components on the retina: a systematic review

Purpose: Cannabis is the most prevalent drug in the world and its consumption is growing. Cannabinoid receptors are present in the human central nervous system. Recent studies show evidence of the effects of cannabinoids on the retina, and synthesising the results of these studies may be relevant for ophthalmologists. Thus, this review adopts standardised, systematic review methodology to investigate the effects of exposure to cannabis and components on the retina.Methods: We searched five online databases for the combined terms for outcome ("retina") and exposure ("cannabis"). Eligibility of studies were conducted by two independent reviewers, and risk of bias was assessed.Results: We retrieved 495 studies, screened 229 studies, assessed 52 studies for eligibility, and included 16 studies for qualitative analysis. The cannabinoids most frequently investigated were delta-9-tetrahydrocannabinol (THC), abnormal cannabidiol, synthetic cannabinoid, and cannabidiol (CDB). The outcomes most studied were neuroretinal dysfunction, followed by vascular effects. The studies also included investigation of neuroprotective and anti-inflammatory effects and teratogenic effects.Conclusions: This review suggests that cannabinoids may have an important role in retinal processing and function.

Visual and oculomotor outcomes in children with prenatal opioid exposure

PURPOSE OF REVIEW

To summarize the visual and oculomotor outcomes in children with prenatal opioid exposure and review the effects of opioids on the developing central nervous system.

RECENT FINDINGS

Animal models and imaging studies in children suggest that prenatal opioid exposure may affect neuronal survival and result in delayed maturation of white matter tracts and decreased volumes in certain brain areas. Visual evoked potential testing in children demonstrates delayed maturation of the afferent visual system in opioid-exposed groups compared with controls, though 'catch-up' development is seen with longitudinal follow-up. Strabismus and nystagmus are also more common in exposed children, and these findings appear to persist.

SUMMARY

As rates of opioid dependence and prenatal opioid exposure continue to increase, it is important to evaluate the short-term and long-term effects of opioids on the developing visual system. An understanding of these risks is important when counseling the parents or guardians of opioid-exposed children, though larger studies with more long-term follow-up will improve our prognostic abilities.

Childhood neurodevelopment after prescription of maintenance methadone for opioid dependency in pregnancy: a systematic review and meta-analysis

AIM

To systematically review and meta-analyse studies of neurodevelopmental outcome of children born to mothers prescribed methadone in pregnancy.

METHOD

MEDLINE, Embase, and PsycINFO were searched for studies published from 1975 to 2017 reporting neurodevelopmental outcomes in children with prenatal methadone exposure.

RESULTS

Forty-one studies were identified (2283 participants). Eight studies were amenable to meta-analysis: at 2 years the Mental Development Index weighted mean difference of children with prenatal methadone exposure compared with unexposed infants was -4.3 (95% confidence interval [CI] -7.24 to -1.63), and the Psychomotor Development Index weighted mean difference was -5.42 (95% CI -10.55 to -0.28). Seven studies reported behavioural scores and six found scores to be lower among methadone-exposed children. Twelve studies reported visual outcomes: nystagmus and strabismus were common; five studies reported visual evoked potentials of which four described abnormalities. Factors that limited the quality of some studies, and introduced risk of bias, included absence of blinding, small sample size, high attrition, uncertainty about polydrug exposure, and lack of comparison group validity.

INTERPRETATION

Children born to mothers prescribed methadone in pregnancy are at risk of neurodevelopmental problems but risk of bias limits inference about harm. Research into management of opioid use disorder in pregnancy should include evaluation of childhood neurodevelopmental outcome.

WHAT THIS PAPER ADDS

Children born to opioid-dependent mothers prescribed methadone are at risk of neurodevelopmental impairment. Exposed infants have lower Mental Development Index and Psychomotor Development Index scores than unexposed children. Atypical visual evoked potentials, strabismus, and nystagmus have increased prevalence. Estimates of impairment may be biased by intermediate to poor quality evidence.

"Choose Physical Therapy" for Neonatal Abstinence Syndrome: Clinical Management for Infants Affected by the Opioid Crisis

In response to the opioid crisis, the American Physical Therapy Association has strongly advocated for physical therapy as a safe alternative to pharmacological pain management through the "#ChoosePT" campaign and the dedication of a PTJ special issue to the nonpharmacological management of pain. Physical therapists not only play an important role in the rehabilitation of the nearly 2 million adolescents and adults addicted to prescription opioids but also provide care to infants born to mothers with various drug addictions. This Perspective article explores the incidence, pathophysiology, and risk factors for neonatal abstinence syndrome and describes the clinical presentations of withdrawal and neurotoxicity in infants. Discipline-specific recommendations for the physical therapist examination and plan of care, including pharmacological management considerations, are outlined. Nonpharmacological management, including supportive care, feeding, parent education, social aspects of care, and follow-up services, are discussed from a physical therapy perspective. Finally, this article reviews developmental outcomes in infants with neonatal abstinence syndrome and reflects on challenges and future directions of research in this area.

Neonatal abstinence syndrome

Neonatal abstinence syndrome refers to the signs and symptoms attributed to the cessation of prenatal exposure (via placental transfer) to various substances. This Primer focuses on neonatal abstinence syndrome caused by opioid use during pregnancy - neonatal opioid withdrawal syndrome (NOWS). As the global prevalence of opioid use has alarmingly increased, so has the incidence of NOWS. NOWS can manifest with varying severity or not at all, for unknown reasons, but is likely to be associated with multiple factors, both maternal (for example, smoking and additional substance exposures) and neonatal (gestational age, sex and genetics). Care for the infant with NOWS begins with addressing the issues experienced by pregnant women with opioid use disorder. Co-occurring mental illness, economic hardship, intimate partner violence, infectious diseases and limited access to care are common in these women and can result in poor maternal and neonatal outcomes. Although there is no consensus regarding optimal NOWS management, non-pharmacological interventions (such as breastfeeding and rooming-in of the mother and the baby) have become a priority, as they can ameliorate symptoms without the need for further opioid exposure. Untreated NOWS can be associated with morbidity in early infancy, and the long-term consequences of fetal opioid exposure are only beginning to be understood.

Fetal assessment in buprenorphine-maintained women using fetal magnetoencephalography: a pilot study

BACKGROUND AND AIMS

In-utero exposure to opioids including buprenorphine (BUP) has been shown to affect fetal activity, specifically heart-rate variability (FHRV) and fetal movement (FM). Our objective was to extract simultaneous recordings of fetal cardiac and brain-related activity in BUP-maintained and non-opioid exposed pregnant women using a novel non-invasive biomagnetic technique.

DESIGN

A pilot study was conducted, recording and analyzing biomagnetic data from fetuses of BUP-maintained and non-opioid exposed pregnant women. Signals were acquired with the non-invasive 151-channel SARA (SQUID-Array for Reproductive Assessment) system. Advanced signal-processing techniques were applied to extract fetal heart and brain activity.

SETTING

University of Arkansas for Medical Sciences (UAMS, Little Rock, Arkansas, USA).

PARTICIPANTS

Eight BUP-maintained pregnant women from UAMS Women's Mental Health Program between gestational ages (GA) of 29-37 weeks who were treated with 8-24 mg of BUP daily. Sixteen pregnant women with no known opioid exposure in the same GA range were also included.

MEASUREMENTS

Outcome measures from the fetal heart and brain signals included: heart rate (FHR), FM, FHR accelerations, FHR-FM coupling, FHRV, fetal behavioral states (FBS) and power spectral density (PSD) of spontaneous brain activity. These measures were analyzed at three GA intervals.

FINDINGS

Fetal heart and brain activity parameters were extracted and quantified successfully from 18 non-opioid and 16 BUP recordings. Overall analysis in both groups show that: FHR and FM ranged from 131 to 141 beats per minute (b.p.m.) and 5 to 11 counts, respectively. In the 35-37 weeks GA, the coupling duration (~9 s) was the shortest, while three of the FHRV parameters were the highest. The PSD of brain activity revealed highest power in 0.5-4 Hz bandwidth. Transitions in FBS from quiet to active sleep were > 50% of sessions.

CONCLUSIONS

This pilot study showed that a novel biomagnetic technique allows simultaneous quantification of cardiac and brain activities of a group of buprenorphine-exposed and non-exposed fetuses in the third trimester.

ERP correlates of cognitive control in children prenatally exposed to methadone or buprenorphine

Much is still unknown about the potential long-term effects of prenatal methadone and buprenorphine exposure. We examined neural correlates of cognitive control in 19 prenatally methadone and buprenorphine exposed and 21 nondrug exposed children, aged 9-11 years. Children performed a modified version of the Eriksen Flanker task, which taps into selective attention, conflict response, and response inhibition mechanisms. We investigated behavioral responses and the ERP components N1, P2, N2, P3, and the late positive component (LPC). Children in the exposed group showed normal cognitive control function. However, an atypical ERP response related to perceptual and attention allocation processes was found in the exposed group.

Retrospective review of neurodevelopmental outcomes in infants treated for neonatal abstinence syndrome

OBJECTIVE

Little is known about developmental outcomes in neonatal abstinence syndrome (NAS). We hypothesized that children treated for NAS would score lower than the normative sample on the Bayley Scales of Infant Development, 3rd edition.

STUDY DESIGN

We performed a retrospective cohort study of 87 infants treated for NAS and evaluated at 2 years of age.

RESULTS

Children treated for NAS scored significantly lower than the norm (mean 100) on all 3 subscales (cognitive mean 96.5, language mean 93.8, motor mean 94.0, all p < 0.03). Children who lived with foster/adoptive families at follow up had higher cognitive scores (median 100 vs. 95, p = 0.03) than those who lived with biological relatives, and were less likely to have motor scores <85 (p = 0.02). Eight percent of children required treatment for strabismus.

CONCLUSIONS

Children treated for NAS are at risk for lower developmental scores and higher rates of strabismus at age 2 than the general population.

Neuroanatomical characteristics of youths with prenatal opioid and poly-drug exposure

Neuroanatomical and cognitive differences have been documented during childhood between children with prenatal opioid- and poly-drug exposure and controls in small samples. We investigated whether these differences persisted in larger samples of youth at older ages. Quantitative MRI and cognitive data were compared between 38 youths in the risk group and 44 youths in the non-exposed group (aged 17 to 22 years) who had been followed prospectively since birth. Most drug-exposed youths (84%) moved to permanent foster or adoptive homes before one year of age. The drug-exposed group displayed smaller neuroanatomical volumes (0.70 SD difference in total brain volume, p = 0.001), smaller cortical surface areas and thinner cortices than the comparison group. The birth weight accounted for some of the intergroup differences. Neuroanatomical characteristics partially mediated group differences in cognitive function. The present study cannot differentiate between causal factors but indicates persistent neurocognitive differences associated with prenatal opioid or poly-drug exposure.

Sensorimotor outcomes in children with prenatal exposure to methadone

PURPOSE

To report the presentation and characteristics of strabismus in children with prenatal methadone exposure.

METHODS

The medical records of children with prenatal methadone exposure were retrospectively reviewed. Those who were evaluated by pediatric ophthalmology were included. Information on the timing and types of prenatal exposure by trimester of pregnancy was then collected from the patients' mothers' charts. The children's perinatal histories and ophthalmologic findings were collected from their pediatric clinic charts and ophthalmology clinic charts, respectively.

RESULTS

A total of 210 children with prenatal methadone exposure were identified, of whom 32 (15.2%) underwent eye examinations and 21 (10%) had strabismus. Five patients had esodeviations, with a mean age of onset of 11.6 months; 16 had exodeviations, with a mean age of onset of 6.8 months. Three patients with strabismus were born prematurely, and 2 had intracranial disease. Two patients underwent strabismus surgery.

CONCLUSIONS

The incidence of strabismus in patients with prenatal methadone exposure was higher than in the general population (10% vs 3%-4%). Intermittent exotropia was the most common type of strabismus and presented earlier than in the general population, with no association with other systemic disease. Prenatal exposure to methadone was likely confounded by exposure to other substances, environmental factors, and genetics. Poor compliance with follow-up reduced the power of the study.

Intraprofessional Excellence in Nursing: Collaborative Strategies for Neonatal Abstinence Syndrome

Neonatal abstinence syndrome (NAS) is a growing public health concern, one that costs the health care system $190-$720 million each year. Recently, state-level perinatal quality collaborative groups have disseminated NAS action plans: customizable frameworks aimed to assist health care systems in identifying, evaluating, treating, and coordinating discharge services for neonates with NAS. Hospital-based neonatal nursing quality improvement teams, including neonatal nurse practitioners (NNPs), neonatal clinical nurse specialists (CNSs), and clinical neonatal nurses, by virtue of their collective academic, administrative, and practical years of experience, are ideally positioned to develop, implement, and evaluate NAS care bundles. The article's purpose is to discuss key elements of an NAS care bundle using the framework of the Perinatal Quality Collaborative of North Carolina NAS action plan as an exemplar. Discussion of evidence-based and nursing-driven metrics will be followed by a discussion of the emerging concept of an inpatient-to-outpatient transitional care NAS management model.

Neonatal abstinence syndrome and the gastrointestinal tract

Development of a healthy gut microbiome is essential in newborns to establish immunity and protection from pathogens. Recent studies suggest that infants who develop dysbiosis may be at risk for lifelong adverse health consequences. Exposure to opioid drugs during pregnancy is a factor of potential importance for microbiome health that has not yet been investigated. Since these infants are born after an entire gestation exposed to mu opioid receptor agonists and have severe gastrointestinal and neurological symptoms, we hypothesize that these infants are at risk for dysbiosis. We speculate that opioid exposure during gestation and development of NAS at birth may lead to a dysbiotic gut microbiome, which may impair normal microbiome succession and development, and impact future health of these children.

Long-Term Outcomes of Infants with Neonatal Abstinence Syndrome

Parents of infants with neonatal abstinence syndrome (NAS) in the NICU may have questions about the long-term consequences of prenatal exposure to methadone, both asked and unasked. Although the signs of withdrawal will abate relatively quickly, parents should be aware of potential vision, motor, and behavioral/cognitive problems, as well as sleeping disturbances and ear infections so their infants can be followed closely and monitored by their pediatrician with appropriate referrals made. Furthermore, this knowledge may inspire parents to enroll their infants in an early intervention program to help optimize their outcomes. There are still many unanswered questions about epigenetic consequences, risk for child abuse/neglect, and risk of future substance abuse in this population.

Prenatally buprenorphine-exposed children: health to 3 years of age

Our prospective study is among the first attempts to examine the health of prenatally buprenorphine-exposed children after neonatal age and to determine the types of child maltreatment in this patient group. The study population included 102 children (61/41 Caucasian males/females) who had a positive urine screen for buprenorphine as a newborn. In addition to buprenorphine, the children were also prenatally exposed to other substances. The data were collected by pediatricians in follow-up visits until 3 years of age and from medical records. Ten prenatally buprenorphine-exposed children (10 %) had some birth defect. The study children had slightly more major anomalies than newborns on average in Finland (3.4 %). Eye disorders (nystagmus, opticus atrophy, and strabismus) occurred in 11 % of children. One child was diagnosed with hepatitis C transmission. One female died of sudden infant death syndrome (SIDS), and one male died of congenital heart disease. Pediatricians submitted altogether 70 reports to child welfare services of suspected maltreatment. Of these reports, 45 (64 %) involved medical neglect. Physical abuse was suspected in four reports.

CONCLUSION

We suggest that prenatally buprenorphine-exposed children have several types of problems with their health at toddler age and that they are susceptible to child maltreatment, especially to medical neglect.

Reasons for Rehospitalization in Children Who Had Neonatal Abstinence Syndrome

BACKGROUND AND OBJECTIVES

Neonatal abstinence syndrome (NAS) occurs after in utero exposure to opioids, but outcomes after the postnatal period are unclear. Our objectives were to characterize childhood hospitalization after NAS.

METHODS

Population-based linkage study of births, hospitalization, and death records of all children registered in New South Wales (NSW), Australia, between 2000 and 2011 to a maximum of 13 years. Infants with an International Statistical Classification of Disease and Related Problems, 10th Edition, Australian Modification, coding of NAS (P96.1, n = 3842) were compared with 1,018,421 live born infants without an NAS diagnosis.

RESULTS

Infants with NAS were more likely to be admitted into a nursery (odds ratio 15.6, 95% confidence interval: 14.5-16.8) and be hospitalized longer (10.0 vs 3.0 days). In childhood, they were more likely to be rehospitalized (1.6, 1.5-1.7), die during hospitalization (3.3, 2.1-5.1), and be hospitalized for assaults (15.2, 11.3-20.6), maltreatment (21.0, 14.3-30.9), poisoning (3.6, 2.6-4.8), and mental/behavioral (2.6, 2.1-3.2) and visual (2.9, 2.5-3.5) disorders. Mothers of infants with NAS were more likely to be Indigenous (6.4, 6.0-7.0), have no antenatal care (6.6, 5.9-7.4), and be socioeconomically deprived (1.6, 1.5-1.7). Regression analyses demonstrated that NAS was the most important predictor of admissions for maltreatment (odds ratio 4.5, 95% confidence interval: 3.4-6.1) and mental and behavioral disorders (2.3, 1.9-2.9), even after accounting for prematurity, maternal age, and Indigenous status.

CONCLUSIONS

Children with NAS are more likely to be rehospitalized during childhood for maltreatment, trauma, and mental and behavioral disorders even after accounting for prematurity. This continues to adolescence and emphasizes the critical need for continued support of this vulnerable group after resolution of NAS.

Global motion perception is independent from contrast sensitivity for coherent motion direction discrimination and visual acuity in 4.5-year-old children

Global motion processing depends on a network of brain regions that includes extrastriate area V5 in the dorsal visual stream. For this reason, psychophysical measures of global motion perception have been used to provide a behavioral measure of dorsal stream function. This approach assumes that global motion is relatively independent of visual functions that arise earlier in the visual processing hierarchy such as contrast sensitivity and visual acuity. We tested this assumption by assessing the relationships between global motion perception, contrast sensitivity for coherent motion direction discrimination (henceforth referred to as contrast sensitivity) and habitual visual acuity in a large group of 4.5-year-old children (n=117). The children were born at risk of abnormal neurodevelopment because of prenatal drug exposure or risk factors for neonatal hypoglycemia. Motion coherence thresholds, a measure of global motion perception, were assessed using random dot kinematograms. The contrast of the stimuli was fixed at 100% and coherence was varied. Contrast sensitivity was measured using the same stimuli by fixing motion coherence at 100% and varying dot contrast. Stereoacuity was also measured. Motion coherence thresholds were not correlated with contrast sensitivity or visual acuity. However, lower (better) motion coherence thresholds were correlated with finer stereoacuity (ρ=0.38, p=0.004). Contrast sensitivity and visual acuity were also correlated (ρ=-0.26, p=0.004) with each other. These results indicate that global motion perception for high contrast stimuli is independent of contrast sensitivity and visual acuity and can be used to assess motion integration mechanisms in children.

Visual evoked potential latencies of three-year-old children prenatally exposed to buprenorphine or methadone compared with non-opioid exposed children: The results of a longitudinal study

This study compared the latency of pattern reversal visual evoked potentials (VEP) of 36-month old children exposed to opioid pharmacotherapy in utero to that of a group of non-exposed children. Pregnant women were enrolled as part of an open-label non-randomised flexible dosing longitudinal study. Participants were 21 children whose mothers were treated with buprenorphine- (n=11) or methadone-pharmacotherapy (n=10) during pregnancy, and 15 children not exposed to opioids in pregnancy. One-way between groups analyses of variance (ANOVA) were conducted to test the statistical significance of differences between the mean latencies of the peak response to two different sized checkerboard patterns (48' and 69' of retinal arc). Standard multiple regression analyses were conducted to determine whether there was a significant relationship between group status and VEP latencies after adjusting for the effect of covariates. VEP latencies ranged from 98 to 112 milliseconds (ms) for checks of 48' arc, and from 95 to 113ms for checks of 69' arc. Latencies were comparable across groups. After adjusting for covariates children prenatally exposed to methadone or buprenorphine did not differ significantly from non-opioid exposed children in their responses to either check size. Nor were there any significant differences in VEP latencies between children prenatally exposed to methadone and children prenatally exposed to buprenorphine. Head circumference (HC) was significantly associated with P100 latencies for both check sizes. Data from this controlled, non-randomised study suggest that neither buprenorphine nor methadone appear to have any long-term effects on visual maturity assessed at 36months of age.

Tapering from Methadone or Buprenorphine during Pregnancy: Maternal and Neonatal Outcomes in Norway 1996-2009

BACKGROUND

The tapering of methadone or buprenorphine during pregnancy is an understudied and controversial issue. The aim of this study was to determine to what extent women tapered their opioid medication dose during pregnancy and what the neonatal outcomes were for those who tapered compared to the women who did not.

METHODS

The study was a mixed prospective/retrospective national cohort study of 123 Norwegian women in opioid maintenance treatment (OMT) during pregnancy and their neonates. A standardized questionnaire was administered to the women and medical information that could be used for verification was collected from hospitals and municipalities.

RESULTS

Two of the women came off the OMT-medication during pregnancy and another 15% tapered their OMT-medication dose more than 50%. The birth weights of methadone-exposed neonates of the women who tapered more than 50% were significantly higher than for the methadone-exposed neonates of the women tapering between 11 and 50%. No other significant differences were found.

CONCLUSION

Pregnant women in OMT who taper their OMT-medication dose should be monitored closely. We need studies that document the maternal well-being and fetal safety of maternal tapering of the OMT-medication during pregnancy.

Neonatal abstinence syndrome: evaluating the effectiveness of an evidence-based multidisciplinary care approach

An evidence-based, multidisciplinary neonatal abstinence syndrome protocol was developed using a stepwise continuous quality improvement (CQI) approach with the goal of standardizing care procedures for these infants. A retrospective secondary data analysis was performed to evaluate the differential effects of each step of the CQI project on 4 key clinical outcome measures: length of stay (total and post-opioid wean), weaning time from opioids, and use of adjunct medications. Data were analyzed from 386 newborn infants with a diagnosis of neonatal abstinence syndrome undergoing treatment in a level III neonatal intensive care unit. After implementation of a pharmacologic weaning protocol as a foundational first step of the CQI project, the weaning time from opioids remained stable throughout each of the subsequent CQI steps (P = .905). The overall total neonatal intensive care unit length of stay was reduced by 10.35 days (P = .002), and the length of neonatal intensive care unit stay after completing wean from opioids was reduced by 2.79 days (P < .001). Use of adjunct medications also decreased from 30.1% of infants at the initiation of the CQI project to 24.5% at the completion of the project (P = .020). These findings indicate that this multidisciplinary treatment approach led to an overall improved efficiency of both opioid weaning and symptom management for these infants.

Neurobehavioral consequences of chronic intrauterine opioid exposure in infants and preschool children: a systematic review and meta-analysis

BACKGROUND

It is assumed within the accumulated literature that children born of pregnant opioid dependent mothers have impaired neurobehavioral function as a consequence of chronic intrauterine opioid use.

METHODS

Quantitative and systematic review of the literature on the consequences of chronic maternal opioid use during pregnancy on neurobehavioral function of children was conducted using the Meta-analysis of Observational Studies in Epidemiology (MOOSE) and the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. We searched Cinahl, EMBASE, PsychINFO and MEDLINE between the periods of January 1995 to January 2012.

RESULTS

There were only 5 studies out of the 200 identified that quantitatively reported on neurobehavioral function of children after maternal opioid use during pregnancy. All 5 were case control studies with the number of exposed subjects within the studies ranging from 33-143 and 45-85 for the controls. This meta-analysis showed no significant impairments, at a non-conservative significance level of p < 0.05, for cognitive, psychomotor or observed behavioural outcomes for chronic intra-uterine exposed infants and pre-school children compared to non-exposed infants and children. However, all domains suggested a trend to poor outcomes in infants/children of opioid using mothers. The magnitude of all possible effects was small according to Cohen's benchmark criteria.

CONCLUSIONS

Chronic intra-uterine opioid exposed infants and pre-school children experienced no significant impairment in neurobehavioral outcomes when compared to non-exposed peers, although in all domains there was a trend to poorer outcomes. The findings of this review are limited by the small number of studies analysed, the heterogenous populations and small numbers within the individual studies. Longitudinal studies are needed to determine if any neuropsychological impairments appear after the age of 5 years and to help investigate further the role of environmental risk factors on the effect of 'core' phenotypes.

Reduced fetal growth in methadone-maintained pregnancies is not fully explained by smoking or socio-economic deprivation

AIM

To determine if reduced fetal growth in infants of opioid-dependent mothers prescribed methadone maintenance in pregnancy is explained by cigarette smoking or socio-economic deprivation.

DESIGN

Retrospective cohort study.

SETTING

Inner-city maternity unit in Scotland.

PARTICIPANTS

A total of 366 singleton infants of methadone-prescribed opioid-dependent mothers compared with the Scottish birth population (n=103 366) as a whole.

MEASUREMENTS

Primary outcome measures were birth weight and head circumference.

FINDINGS

In infants of methadone-prescribed opioid-dependent mothers mean birth weight was 259 g [95% confidence interval (CI) 214-303 g; P<0.0001] less, and mean head circumference 1.01 cm (95% CI 0.87-1.15 cm; P<0.0001) less than in controls, allowing for gestation, cigarette smoking, area deprivation, infant sex and maternal age and parity. This represents an adjusted difference of -0.61 (95% CI -0.52--0.71; P<0.0001) Z-score in mean birth weight and -0.77 (95% CI -0.66--0.89; P<0.0001) Z-score in mean head circumference.

CONCLUSIONS

Reduced fetal growth in infants of opioid-dependent mothers prescribed methadone maintenance in pregnancy is not fully explained by cigarette smoking, area deprivation, maternal age or parity.

Deviant smooth pursuit in preschool children exposed prenatally to methadone or buprenorphine and tobacco affects integrative visuomotor capabilities

BACKGROUND AND AIMS

Although an increasing number of children are born to mothers in opioid maintenance therapy (OMT), little is known about the long-term effects of these opioids. Previous studies suggest an association between prenatal OMT exposure and difficulties in eye movement control. Also, the effects of tobacco smoking on eye movements have been reported. The present study examined the influence of eye movements, i.e. smooth pursuit, on visuomotor capabilities in children of smoking mothers in OMT.

DESIGN

The study comprised a 2 (OMT versus contrast group) × 2 (slow versus fast smooth pursuit) between-subject factorial design.

SETTING

The cognitive developmental research unit at the University of Oslo, Norway.

PARTICIPANTS

Participants were 26 4-year-old children of tobacco-smoking women in OMT and 23 non-exposed 4-year-old children, with non-smoking mothers, matched by gender and age.

MEASUREMENT

Eye movements and smooth pursuit were recorded using a Tobii 1750 eyetracker. Visuomotor functions were examined by Bender test.

FINDINGS

The OMT group tracked slowly moving objects with smooth pursuit in a similar manner to their non-exposed peers. When fast smooth pursuit was measured, the OMT group of children tracked the object more slowly than the contrast group, P = 0.02, ηp(2) = 0.11. A regression analysis showed that fast smooth pursuit predicted children's performance on a visuomotor task, R(2) = 0.37.

CONCLUSION

Impaired eye-tracking skills in 4-year-old children exposed to methadone or buprenorphine and tobacco prenatally could inhibit the development of some cognitive functions in later life.

Ocular manifestations of drug and alcohol abuse

PURPOSE OF REVIEW

The purpose of this study is to review commonly encountered adverse ocular effects of illicit drug use.

RECENT FINDINGS

Drug and alcohol abuse can produce a variety of ocular and neuro-ophthalmic side effects. Novel, so-called 'designer', drugs of abuse can lead to unusual ocular disorders. Legal substances, when used in manners for which they have not been prescribed, can also have devastating ophthalmic consequences.

SUMMARY

In this review, we will systematically evaluate each part of the visual pathways and discuss how individual drugs may affect them.

Congenital nystagmus in two infants born from mothers exposed to methadone during pregnancy

Background

Methadone is commonly prescribed as a substitute for illicit opioids. Use of methadone during pregnancy is associated with neonatal abstinence syndrome (NAS), reduced head circumference as well as a slight increase in neonatal mortality and morbidity. Less is known about the effects of methadone on the visual system.

Cases

We report two Italian cases of nystagmus in infants born from mothers exposed to methadone during pregnancy. Ophthalmic or central disorders were excluded as a cause of nystagmus in both infants. The first case was followed at 3, 6 and 12 months while the second one was evaluated at 5 and 8 months. Both infants had normal neurological and cognitive development. Their first evaluation revealed different characteristics but both showed progressive improvement in ocular disorder, persistence of pendular horizontal nystagmus and nearly normal visual acuity.

Conclusion

This report, the first description of Italian cases of nystagmus related to use of methadone during pregnancy, underlies the importance of a careful investigation of drug use in pregnancy in cases of unexplained congenital nystagmus.

The short- and long-term effects on the visual system of children following exposure to maternal substance misuse in pregnancy

PURPOSE

To document the prevalence of ophthalmic morbidities in babies born to mothers who misused substances in pregnancy and to assess whether it changes over 5 years.

DESIGN

Retrospective comparative case series.

METHODS

The series included: (1) a retrospective review of 301 children born between 2000 and 2004 to mothers misusing substances during pregnancy; (2) assessment at 5-year follow-up of this cohort; and (3) comparison with 7887 age-matched controls drawn from the preschool screening cohort in the north of Scotland in the same time period. Odds ratios (OR) and 95% confidence intervals (CI) were calculated. Following data collection in both patient and control groups, the following were calculated: (1) rate of referral to the ophthalmology department; (2) prevalence of nystagmus and strabismus at presentation in the study group and at 5 years of age in both patient and control group; (3) prevalence of reduced visual acuity and lack of stereopsis.

RESULTS

Ophthalmology referrals, strabismus, and nystagmus were found to be statistically significantly higher in the study group compared with the control group. In the study group, at baseline referral, 46 of 301 (15.3%) had strabismus (2.8% in control group) and 11 of 301 (3.7%) nystagmus (0.004% in control group). At 5-year follow-up, the prevalence of strabismus was 14.0% (OR 5.70, 95% CI: 4.01-8.12) and that of nystagmus was 3.3% (OR 90.34, 95% CI 24.73-330.02). A total of 42.4% of these children at age 5 had no demonstrable binocular vision and 28.2% had visual acuity of 0.3 (logMAR) or worse in 1 or both eyes. Clinic attendance at last follow-up was poor (61.9%).

CONCLUSIONS

Exposure to maternal drug misuse in utero is associated with a statistically significantly higher prevalence of strabismus and nystagmus. These abnormalities tend to persist at 5 years of age and are associated with long-term visual morbidity, such as lack of binocularity and poor visual acuity. Our study highlights the need for ophthalmologic surveillance of this population and supports attendance, as nonattendance may be linked to more problems with substance misuse in parents and greater pathology in the child.

Neonatal visual evoked potentials in infants born to mothers prescribed methadone

OBJECTIVE

Drug misuse in pregnancy is associated with impaired infant visual development. Pilot data showed abnormal flash visual evoked potentials (VEPs) in neonates exposed to methadone in utero, but results were confounded by intrauterine growth restriction, gestation, and ongoing drug misuse. This large cohort study aimed to clarify the effects on neonatal flash VEPs of maternal drug misuse in pregnancy, including prescription of substitute methadone and subsequent development of neonatal abstinence syndrome.

METHODS

This was a prospective cohort study. Flash VEPs were recorded within 3 days of birth from 100 healthy infants of drug-misusing mothers prescribed substitute methadone during pregnancy and 50 comparison infants matched for birth weight, gestation, and socioeconomic deprivation. VEP morphology was classified as mature, typical, or immature, and amplitudes and implicit times of the major waveform components measured. Drug exposure was determined by maternal history, maternal and infant urine, and meconium toxicology.

RESULTS

VEPs from maternal drug-exposed infants were more likely to be of immature waveform (P < .001) and were smaller in overall amplitude (median 27 µV vs 39 µV, P < .001) compared with non-drug-exposed infants. Most infants were exposed to illicit drugs in addition to prescribed methadone; differences in VEP parameters were independently associated with maternal prescribed methadone and persisted after correcting for birth weight, cigarette smoking, and excess in utero alcohol exposure.

CONCLUSIONS

In utero exposure to prescribed substitute methadone is associated with altered flash VEPs in the newborn period and these infants may warrant early clinical visual assessment.