Foetal alcohol spectrum disorder: identifying the neurobehavioural phenotype and effective interventions

Examining the effects of prenatal alcohol exposure on performance of the sustained attention to response task in children with an FASD

Prenatal alcohol exposure (PAE), the leading known cause of childhood developmental disability, has long-lasting effects extending throughout the lifespan. It is well documented that children prenatally exposed to alcohol have difficulties inhibiting behavior and sustaining attention. Thus, the Sustained Attention to Response Task (SART), a Go/No-go paradigm, is especially well suited to assess the behavioral and neural functioning characteristics of children with PAE. In this study, we utilized neuropsychological assessment, parent/guardian questionnaires, and magnetoencephalography during SART random and fixed orders to assess characteristics of children 8-12 years old prenatally exposed to alcohol compared to typically developing children. Compared to neurotypical control children, children with a Fetal Alcohol Spectrum Disorder (FASD) diagnosis had significantly decreased performance on neuropsychological measures, had deficiencies in task-based performance, were rated as having increased Attention-Deficit/Hyperactivity Disorder (ADHD) behaviors and as having lower cognitive functioning by their caretakers, and had decreased peak amplitudes in Broadmann's Area 44 (BA44) during SART. Further, MEG peak amplitude in BA44 was found to be significantly associated with neuropsychological test results, parent/guardian questionnaires, and task-based performance such that decreased amplitude was associated with poorer performance. In exploratory analyses, we also found significant correlations between total cortical volume and MEG peak amplitude indicating that the reduced amplitude is likely related in part to reduced overall brain volume often reported in children with PAE. These findings show that children 8-12 years old with an FASD diagnosis have decreased amplitudes in BA44 during SART random order, and that these deficits are associated with multiple behavioral measures.

Interventions for improving executive functions in children with foetal alcohol spectrum disorder (FASD): A systematic review

Background

The consequences for children born with birth defects and developmental disabilities encompassed by foetal alcohol spectrum disorder (FASD) are profound, affecting all areas of social, behavioural and cognitive functioning. Given the strong evidence for a core deficit in executive functioning, underpinned by impaired self-regulation skills, there has been a growing focus on the development of interventions that enhance or support the development of executive functions (EFs).

Objectives

The primary objective of this review is to synthesise the evidence for structured psychological interventions that explicitly aim to improve EF in children. The review also sought to ascertain if the effectiveness of interventions were influenced by characteristics of the intervention, participants or type of EF targeted by the intervention.

Search Methods

Sixteen databases, 18 grey literature search locations and 9 trial registries were systematically searched to locate eligible studies (up to December 2020). These searches were supplemented with reference harvesting, forward citation searching, hand searches of topic-relevant journals and contact with experts.

Selection Criteria

Studies were included in the review if they reported on an impact evaluation of a psychological intervention aiming to improve EF in children 3-16 years who either had confirmed prenatal alcohol exposure or a formal diagnosis falling under the umbrella term of FASDs. Eligible study designs included randomised controlled trials (RCTs) and quasi-experimental designs with either no treatment, wait list control or an alternative treatment as a comparison condition. Single-group pre-post designs were also included.

Data Collection and Analysis

Standard methodological procedures expected by the Campbell Collaboration were used at all stages of this review. Standardised mean differences (SMDs) were used to estimate intervention effects, which were combined with random effects meta-analysis (data permitting). Risk of bias was assessed using the Cochrane Risk of Bias Tool (RoB2) and Cochrane Risk of Bias in Non-Randomised Studies-Interventions tool (ROBINS-I).

Main Results

The systematic search identified 3820 unique records. After title/abstract and full-text screening, 11 eligible studies (reported in 21 eligible documents) were deemed eligible, with a combined 253 participants. Of the 11 studies, 6 were RCTs, 1 was a quasi-experiment and 4 were single-group pre-post intervention designs. All studies were rated as having an overall high or serious risk of bias, with some variation across domains for RCTs. For RCT and quasi-experimental studies, the overall effect of EF interventions on direct and indirect measures of EF generally favoured the experimental condition, but was not statistically significant. There was no difference between intervention and comparison groups on direct measures of auditory attention (k = 3; SMD = 0.06, 95% confidence interval [CI] = -1.06, 1.18), visual attention (k = 2; SMD = 0.90, 95% CI = -1.41, 3.21), cognitive flexibility (k = 2; SMD = 0.23, 95% CI = -0.40, 0.86), attentional inhibition (k = 2; SMD = 0.04, 95% CI = -0.58, 0.65), response inhibition (k = 3; SMD = 0.47, 95% CI = -0.04, 0.99), or verbal working memory (k = 1; d = 0.6827; 95% CI = -0.0196, 1.385). Significant heterogeneity was found across studies on measures of auditory attention and visual attention, but not for measures of cognitive flexibility, attentional inhibition or response inhibition. Available data prohibited further exploration of heterogeneity. There was no statistical difference between intervention and comparison groups on indirect measures of global executive functioning (k = 2; SMD = 0.21, 95% CI = -0.40, 0.82), behavioural regulation (k = 2; SMD = 0.18, 95% CI = -0.43, 0.79), or emotional control (k = 3; SMD = 0.01, 95% CI = -0.33, 0.36). Effect sizes were positive and not significant for meta-cognition (k = 1; SMD = 0.23, 95% CI = -0.72, 1.19), shifting (k = 2; SMD = 0.04, 95% CI = -0.35, 0.43), initiation (k = 1; SMD = 0.04, 95% CI = -0.40, 0.49), monitoring (k = 1; SMD = 0.25, 95% CI = -0.20, 0.70) and organisation of materials (k = 1; SMD = 0.25, 95% CI = -0.19, 0.70). Effect sizes were negative and not statistically different for effortful control (k = 1; SMD = -0.53, 95% CI = -1.50, 0.45), inhibition (k = 2; SMD = -0.08, 95% CI = -0.47, 0.31), working memory (k = 1; SMD = 0.00, 95% CI = -0.45, 0.44), and planning and organisation (k = 1; SMD = -0.10, 95% CI = -0.55, 0.34). No statistically significant heterogeneity was found for any of the syntheses of indirect measures of EF. Based on pre-post single-group designs, there was evidence for small to medium sized improvements in EF based on direct measures (cognitive flexibility, verbal working memory and visual working memory) and indirect measures (behavioural regulation, shifting, inhibition and meta-cognition). However, these results must be interpreted with caution due to high risk of bias.

Authors' Conclusions

This review found limited and uncertain evidence for the effectiveness of interventions for improving executive functioning in children with FASD across 8 direct and 13 indirect measures of EF. The findings are limited by the small number of high-quality studies that could be synthesised by meta-analysis and the very small sample sizes for the included studies.

The contribution of the Neurobehavioral Screening Tool to identifying fetal alcohol spectrum disorders in children at high risk of prenatal alcohol exposure and neurobehavioral deficits

BACKGROUND

Fetal alcohol spectrum disorders (FASD) describe various conditions resulting from prenatal alcohol exposure. The diagnosis of FASD can be challenging and complex. The Neurobehavioral Screening Tool (NST), derived from Achenbach's Child Behavior Checklist, has been suggested as a tool for identifying FASD.

AIMS

To assess the external validity of the NST and to identify additional characteristics of FASD in a cohort of Israeli children and young adults referred to a neurology and child developmental clinic at a tertiary pediatric medical center in Israel.

STUDY DESIGN

An observational study based on medical records.

SUBJECTS

151 children and young adults, of whom 40 were diagnosed with FASD according to updated clinical guidelines.

OUTCOME MEASURES

NST results, as well as demographic and neurobehavioral variables, were compared between those who were and were not diagnosed with FASD.

RESULTS

The NST demonstrated 72 % to 73 % sensitivity, and 34 % to 36 % specificity, in identifying FASD. Items 4 and 5 ('Lies or cheats', 'Lacks guilt after misbehaving') were the most predictive items in the NST. Other variables that were characteristic of the FASD group included: emotional regulation difficulties (p value <0.01), being born and adopted in Israel (vs. other countries) (p value <0.01) and younger age at the first visit to the clinic (p value <0.01).

CONCLUSIONS

Our findings regarding the screening capabilities of the NST were less promising than those of most previous studies. Further research is needed to establish a valid neurobehavioral tool with the possible focus on antisocial behaviors and emotional regulation problems.

Searching for the Fetal Alcohol Behavioral Phenotype

This narrative review presents the emerging published evidence on the existence of a phenotypic behavior in children with fetal alcohol spectrum behavior. Such a phenotype, exhibiting high sensitivity, specificity, and predictive values, may assist clinicians and families in identifying children who often miss some of the information needed for full diagnosis, but who may benefit from these screening tools in mobilizing help to these youngsters and their families.

Prenatal Alcohol Exposure, FASD, and Child Behavior: A Meta-analysis

CONTEXT

Fetal alcohol spectrum disorders (FASD) and prenatal alcohol exposure (PAE) are associated with behavioral difficulties, although there are no published systematic reviews that summarize and critique the literature.

OBJECTIVE

To describe the behavioral characteristics of children with PAE and/or FASD, assessed using the Achenbach System of Empirically Based Assessments (ASEBA) for school-aged children with parent, teacher, and youth (self-report) forms.

DATA SOURCES

Electronic literature databases, reference lists, hand-searches.

STUDY SELECTION

peer-reviewed observational studies.

DATA EXTRACTION

Study appraisal and data extraction were undertaken by 2 independent assessors. Meta-analyses were performed for parent-rated Internalizing, Externalizing, and Total problems scales. All other ASEBA scales were summarized qualitatively.

RESULTS

Included were 23 articles; 16 were used in meta-analyses. Pooled results showed higher Total (mean difference 12.1, 95% confidence interval [95% CI] 7.7-16.5), Internalizing (6.3, 95% CI 3.1-9.5), and Externalizing problems scores (12.5, 95% CI 7.9-17.0) in FASD than No FASD; and greater odds of scoring in the "Clinical" range in FASD. Pooled results demonstrated higher problem scores in children with PAE (P > .05). Qualitative summaries of other scales from parents, teachers, and self-report show poorer behavior ratings in children with FASD and PAE on composite Problem and Competence scores and many Syndrome subscales.

LIMITATIONS

Findings were restricted to behaviors assessed using the ASEBA. The published literature was limited, often with only 1 study reporting on a particular scale.

CONCLUSIONS

Meta-analysis reveals that FASD and PAE are associated with problematic behavior in many, but not all domains. This clearly affects families, and should be considered in clinical practice by providers.

Adenylyl cylases 1 and 8 mediate select striatal-dependent behaviors and sensitivity to ethanol stimulation in the adolescent period following acute neonatal ethanol exposure

Neonatal alcohol exposure in rodents causes dramatic neurodegenerative effects throughout the developing nervous system, particularly in the striatum, acutely after exposure. These acute neurodegenerative effects are augmented in mice lacking adenylyl cyclases 1 and 8 (AC1/8) as neonatal mice with a genetic deletion of both AC isoforms (DKO) have increased vulnerability to ethanol-induced striatal neurotoxicity compared to wild type (WT) controls. While neonatal ethanol exposure is known to negatively impact cognitive behaviors, such as executive functioning and working memory in adolescent and adult animals, the threshold of ethanol exposure required to impinge upon developmental behaviors in mice has not been extensively examined. Therefore, the purpose of this study was to determine the behavioral effects of neonatal ethanol exposure using various striatal-dependent developmental benchmarks and to assess the impact of AC1/8 deletion on this developmental progression. WT and DKO mice were treated with 2.5 g/kg ethanol or saline on postnatal day (P)6 and later subjected to the wire suspension, negative geotaxis, postural reflex, grid hang, tail suspension and accelerating rotarod tests at various time points. At P30, mice were evaluated for their hypnotic responses to 4.0 g/kg ethanol by using the loss of righting reflex assay and ethanol-induced stimulation of locomotor activity after 2.0 g/kg ethanol. Ethanol exposure significantly impaired DKO performance in the negative geotaxis test while genetic deletion of AC1/8 alone increased grid hang time and decreased immobility time in the tail suspension test with a concomitant increase in hindlimb clasping behavior. Locomotor stimulation was significantly increased in animals that received ethanol as neonates, peaking significantly in ethanol-treated DKO mice compared to ethanol-treated WT controls, while sedation duration following high-dose ethanol challenge was unaffected. These data indicate that the maturational parameters examined in the current study may not be sensitive enough to detect effects of a single ethanol exposure during the brain growth spurt period. Genetic deletion of AC1/8 reveals a role for these cylases in attenuating ethanol-induced behavioral effects in the neonatally-exposed adolescent.