Fetal alcohol syndrome: review of the literature with implications for physical therapists

Prenatal alcohol exposure and infant gross motor development: a prospective cohort study

BACKGROUND

Maternal alcohol consumption in pregnancy may have adverse effects on child gross motor (GM) development. There have been few human studies on this topic, particularly ones examining low exposure. This study examined the association between prenatal alcohol exposure (PAE) and infant GM development at 12-months of age.

METHODS

Participants were 1324 women recruited from antenatal clinics in Sydney and Perth, Australia. Maternal and paternal alcohol use was assessed in pregnancy via interview; offspring GM development was measured at 12-months with the Bayley Scales of Infant Development (BSID-III).

RESULTS

Any alcohol use in pregnancy was common: 56.1%, of pregnant women drank early in Trimester one (0-6 weeks), however this reduced to 27.9% on average thereafter and at predominantly low levels. However, infant BSID GM scale scores were not found to differ significantly as a function of PAE in the first 6-weeks (low, moderate, binge or heavy PAE), nor with low PAE across pregnancy.

CONCLUSIONS

We found no evidence to suggest that low PAE is associated with measurable impairment in infant GM development at 12-months. Further research is needed to examine potential PAE impacts on GM development in heavier exposure groups and through the childhood years when subtle GM deficits may be more detectable.

Gross motor deficits in children prenatally exposed to alcohol: a meta-analysis

BACKGROUND AND OBJECTIVES

Gross motor (GM) deficits are often reported in children with prenatal alcohol exposure (PAE), but their prevalence and the domains affected are not clear. The objective of this review was to characterize GM impairment in children with a diagnosis of fetal alcohol spectrum disorder (FASD) or "moderate" to "heavy" maternal alcohol intake.

METHODS

A systematic review with meta-analysis was conducted. Medline, Embase, Allied and Complementary Medicine Database, Cumulative Index to Nursing and Allied Health Literature, PsycINFO, PEDro, and Google Scholar databases were searched. Published observational studies including children aged 0 to ≤18 years with (1) an FASD diagnosis or moderate to heavy PAE, or a mother with confirmed alcohol dependency or binge drinking during pregnancy, and (2) GM outcomes obtained by using a standardized assessment tool. Data were extracted regarding participants, exposure, diagnosis, and outcomes by using a standardized protocol. Methodological quality was evaluated by using Strengthening the Reporting of Observational Studies in Epidemiology guidelines.

RESULTS

The search recovered 2881 articles of which 14 met the systematic review inclusion criteria. The subjects' mean age ranged from 3 days to 13 years. Study limitations included failure to report cutoffs for impairment, nonstandardized reporting of PAE, and small sample sizes. The meta-analysis pooled results (n = 10) revealed a significant association between a diagnosis of FASD or moderate to heavy PAE and GM impairment (odds ratio: 2.9; 95% confidence interval: 2.1-4.0). GM deficits were found in balance, coordination, and ball skills. There was insufficient data to determine prevalence.

CONCLUSIONS

The significant results suggest evaluation of GM proficiency should be a standard component of multidisciplinary FASD diagnostic services.

Sensory-motor deficits in children with fetal alcohol spectrum disorder assessed using a robotic virtual reality platform

BACKGROUND

Fetal alcohol spectrum disorder (FASD) is associated with a large number of cognitive and sensory-motor deficits. In particular, the accurate assessment of sensory-motor deficits in children with FASD is not always simple and relies on clinical assessment tools that may be coarse and subjective. Here we present a new approach: using robotic technology to accurately and objectively assess motor deficits of children with FASD in a center-out reaching task.

METHODS

A total of 152 typically developing children and 31 children with FASD, all aged between 5 and 18 were assessed using a robotic exoskeleton device coupled with a virtual reality projection system. Children made reaching movements to 8 peripheral targets in a random order. Reach trajectories were subsequently analyzed to extract 12 parameters that had been previously determined to be good descriptors of a reaching movement, and these parameters were compared for each child with FASD to a normative model derived from the performance of the typically developing population.

RESULTS

Compared with typically developing children, the children with FASD were found to be significantly impaired on most of the parameters measured, with the greatest deficits found in initial movement direction error. Also, children with FASD tended to fail more parameters than typically developing children: 95% of typically developing children failed fewer than 3 parameters compared with 69% of children with FASD. These results were particularly pronounced for younger children.

CONCLUSIONS

The current study has shown that robotic technology is a sensitive and powerful tool that provides increased specificity regarding the type of motor problems exhibited by children with FASD. The high frequency of motor deficits in children with FASD suggests that interventions aimed at stimulating and/or improving motor development should routinely be considered for this population.

Gestational naltrexone ameliorates fetal ethanol exposures enhancing effect on the postnatal behavioral and neural response to ethanol

The association between gestational exposure to ethanol and adolescent ethanol abuse is well established. Recent animal studies support the role of fetal ethanol experience-induced chemosensory plasticity as contributing to this observation. Previously, we established that fetal ethanol exposure, delivered through a dam's diet throughout gestation, tuned the neural response of the peripheral olfactory system of early postnatal rats to the odor of ethanol. This occurred in conjunction with a loss of responsiveness to other odorants. The instinctive behavioral response to the odor of ethanol was also enhanced. Importantly, there was a significant contributory link between the altered response to the odor of ethanol and increased ethanol avidity when assessed in the same animals. Here, we tested whether the neural and behavioral olfactory plasticity, and their relationship to enhanced ethanol intake, is a result of the mere exposure to ethanol or whether it requires the animal to associate ethanol's reinforcing properties with its odor attributes. In this later respect, the opioid system is important in the mediation (or modulation) of the reinforcing aspects of ethanol. To block endogenous opiates during prenatal life, pregnant rats received daily intraperitoneal administration of the opiate antagonist naltrexone from gestational day 6-21 jointly with ethanol delivered via diet. Relative to control progeny, we found that gestational exposure to naltrexone ameliorated the enhanced postnatal behavioral response to the odor of ethanol and postnatal drug avidity. Our findings support the proposition that in utero ethanol-induced olfactory plasticity (and its relationship to postnatal intake) requires, at least in part, the associative pairing between ethanol's odor quality and its reinforcing aspects. We also found suggestive evidence that fetal naltrexone ameliorated the untoward effects of gestational ethanol exposure on the neural response to non-fetal-exposure odorants. Thus, gestational naltrexone may also have a neuroprotective and/or neuroproliferative impact on olfactory development.

Factors influencing gross motor development in young children in an urban child welfare system

PURPOSE

To determine whether young children involved with child welfare (CW) have gross motor (GM) delay; to examine relationships between GM skills and the influence of multiple factors on GM skills.

METHODS

One hundred seventy-six children involved with CW received GM assessment, physical examinations, and caseworker interviews. Descriptive statistics, correlations, t tests, analysis of variance and covariance, and multiple regression analyses were completed.

RESULTS

GM scores, lower than population norms, were associated with growth parameters. Children in kinship care had significantly higher GM scores compared with children in foster care and those with in-home protective services when adjusted for differences in time in CW. Abuse/neglect, medical neglect, and parental substance abuse produced lower scores; referral for abandonment produced higher scores. Age was most strongly related to GM outcome, with multiple regression explaining 19% of GM variance.

CONCLUSION

Children involved with CW have lower mean GM scores than population norms. Several factors specific to CW experiences may influence GM outcome.

Ethanol exhibits specificity in its effects on differentiation of hematopoietic progenitors

Ethanol is a known teratogen but the mechanisms by which this simple compound affects fetal development remain unresolved. The goal of the current study was to determine the mechanism by which ethanol affects lymphoid differentiation using an in vitro model of ethanol exposure. Primitive hematopoietic oligoclonal-neonatal-progenitor cells (ONP), with the phenotype Lin(-)HSA(lo)CD43(lo)Sca-1(-)c-Kit(+) that are present in neonatal but not adult bone marrow were sorted from the bone marrow of 2-week-old C57BL/6J mice and cultured under conditions that favor either B cell or myeloid cell differentiation with or without addition of ethanol. The overall growth of the ONP cells was not significantly affected by inclusion of up to 100mM ethanol in the culture medium. However, the differentiation of the progenitor cells along the B-cell pathway was significantly impaired by ethanol in a dose-dependent manner. Exposure of ONP cells to 100mM ethanol resulted in greater than 95% inhibition of B cell differentiation. Conversely, ethanol concentrations up to and including 100mM had no significant effect on differentiation along the myeloid pathway. The effect of ethanol on transcription factor expression was consistent with the effects on differentiation. ONP cells grown in 100mM ethanol failed to upregulate Pax5 and EBF, transcriptional regulators that are necessary for B cell development. However, ethanol had no significant effect on the upregulation of PU.1, a transcription factor that, when expressed in high concentration, favors myeloid cell development. Taken together, these results suggest that ethanol has specificity in its effects on differentiation of hematopoietic progenitors.

Sensory processing, school performance, and adaptive behavior of young school-age children with fetal alcohol spectrum disorders

This study described sensory processing behaviors and sensory-motor abilities in children with fetal alcohol spectrum disorders (FASD) and explored their relationship to home and school function. A clinic-referred sample of 25 children with FASD, ages 5 to 8 years, was compared with 26 children with typical development, balanced for age, gender, and race/ethnicity, on standardized tests examining sensory processing, sensory-motor performance, school performance, and adaptive behavior. Children with FASD scored significantly more poorly on sensory processing, sensory-motor, adaptive, and academic achievement measures, and demonstrated more problem behaviors at home and school. Correlations were significant between measures of sensory processing and sensory-motor performance, adaptive behavior, and some aspects of academic performance. Sensory processing and related foundational sensory-motor impairments should be considered when determining the developmental needs of children with FASD. These impairments may co-occur with and contribute, at least in part, to decreased adaptive and school function.

The effect of gestational ethanol exposure on voluntary ethanol intake in early postnatal and adult rats

Clinical and epidemiological studies provide strong data for a relationship between prenatal ethanol exposure and the risk for abuse in adolescent and young adult humans. However, drug-acceptance results in response to fetal exposure have differed by study, age at evaluation, and experimental animal. In the present study, the authors tested whether voluntary ethanol intake was enhanced in both the infantile and adult rat (15 and 90 days of age, respectively), as a consequence of chronic fetal drug experience. Experimental rats were exposed in utero by administering ethanol to a pregnant dam in a liquid diet during gestational Days 6-20. Compared with those for isocaloric pair-fed and ad lib chow control animals, the results for experimental animals demonstrated that fetal exposure significantly increased infantile affinity for ethanol ingestion without affecting intake patterns of an alternative fluid (water). Heightened affinity for ethanol was absent in adulthood. Moreover, the results argue against malnutrition as a principal factor underlying the infantile phenomenon. These data add to a growing literature indicative of heightened early postnatal acceptance patterns resulting from maternal use or abuse of ethanol during pregnancy.

In utero exposure to alcohol alters cell fate decisions by hematopoietic progenitors in the bone marrow of offspring mice during neonatal development

Fetal alcohol syndrome and alcohol related birth defects represent a spectrum of disorders that can result from the consumption of alcohol during pregnancy. Previous studies from this laboratory have shown that alcohol exposure in utero adversely affects hematopoietic progenitors in the bone marrow. Neonatal mice that were exposed in utero to alcohol showed a marked delay in B lymphocyte development. Recent studies have focused on an oligopotential progenitor cell, with the phenotype of HSA(lo)CD43(lo)Lin(-), which yields both B cells and myeloid lineage cells at a high frequency when cultured in vitro with stromal cells and the appropriate cytokines. However, these progenitor cells isolated from neonatal offspring of alcohol fed dams showed a significant decrease in the frequency of B cell formation following in vitro culture. In order to understand the mechanism underlying this defect we examined the expression of key transcription factors (early B cell factor, EBF, and Pax5) in this progenitor pool. Here, we report that >95% of HSA(lo)CD43(lo)Lin(-) cells express EBF and 5% express Pax5. Following liquid culture in the presence of IL-7, these progenitor cells respond by up-regulating Pax5 and the surface expression of CD19 indicating that the cells have committed to the B lineage. By contrast 75% of HSA(lo)CD43(lo)Lin(-) cells isolated from the bone marrow of neonatal animals exposed in utero to alcohol expressed EBF but at a level that was less than 25% the level of cells isolated from control animals. Furthermore, these alcohol-exposed progenitor cells failed to up-regulate Pax5 in response to IL-7 indicating a greatly reduced capacity to expand and differentiate to B lineage cells in liquid cultures. However, the HSA(lo)CD43(lo)Lin(-) cells isolated from the alcohol exposed animals retained the capacity to differentiate to myeloid lineage cells. These results suggest that the interference with the sequential expression of transcription factors in early progenitor cells by in utero alcohol exposure is a potential mechanism for the observed decrease in B lymphocytes in neonatal mice.

In utero alcohol and postnatal methylphenidate: locomotion and dopamine receptors

Prenatal alcohol exposure can cause central nervous system abnormalities and dysfunction referred to as Alcohol-Related Neurodevelopmental Disorder (ARND). Repeated intermittent methylphenidate (Ritalin) was used as a psychopharmacological challenge to reveal functional alterations in dopamine binding sites in rats exposed prenatally to alcohol. Pregnant Long-Evans dams were intubated with 0, 3, or 5 g/kg/day of alcohol from gestational day (GD) 8 to GD20. Adult offspring received repeated intraperitoneal injections of 0, 4, or 8 mg/kg of methylphenidate (MET), and were tested periodically for locomotor activity. Autoradiographic assessment of dopamine D1 and D2 receptors binding were visualized using [3H]SCH 23390 and [3H]raclopride, respectively. Prenatal alcohol did not produce significant dose-dependent effects on adult locomotor activity. Repeated MET injections produced dose-dependent sensitization of locomotor activity in all groups. The 3-g/kg prenatal alcohol group had a significantly decreased number of dopamine D2 binding sites within the dorsal and ventral striatum. This effect was reversed by MET. The neural changes detected in the lower alcohol group may indicate persistent changes within the dopaminergic system due to prenatal alcohol exposure.

Effects of in utero alcohol exposure on B cell development in neonatal spleen and bone marrow

The effects of in utero alcohol exposure on neonatal lymphopoiesis were examined in a murine model of fetal alcohol syndrome. At birth, both immature and mature B cells were decreased in the spleens of neonatal animals and these subpopulations of B cells did not recover to normal levels until 3-4 weeks of life. Pre-B cells and total B cells were decreased as well in the bone marrow of ethanol-exposed animals. By 3-4 weeks of life, the number of B cells in the bone marrow recovered to normal levels, but the pre-B cells remained below normal levels through 5 weeks of age. Furthermore, a recently described early B cell progenitor was reduced in frequency in ethanol-exposed neonates. Together, these data suggest that in utero exposure to ethanol can result in abnormalities in B cell development that may initiate at an early stage of B cell development.

Fetal alcohol syndrome: early olfactory learning as a model system to study neurobehavioral deficits

The goal of basic research examining the deficits underlying fetal alcohol syndrome is to develop an animal model which allows investigation and assessment of the neural and cognitive impairments resulting from prenatal alcohol exposure. The following review focuses on animal models and their relationship to human deficits following prenatal alcohol exposure. In addition, this review examines a unique, well-established model system which may permit an increased understanding of the role of alcohol on the developing brain and cognitive behavior. Specifically, large metabolic, neurochemical, neuropharmacological, morphological and neurophysiological changes in young rats have been reported as a consequence of early olfactory preference conditioning, a form of learning that normally occurs during both human and rat development. This olfactory odor preference training paradigm can be used to assess changes in learning as well as the neural substrates underlying this learning. Olfactory preference training has been used to examine: 1) learning, as demonstrated by a behavioral preference for an odor previously paired with stimulation which mimics maternal care; 2) metabolism, by measuring 2-deoxyglucose uptake and distribution in response to the trained odor; 3) neurotransmitter levels, by using in vivo microdialysis, to examine changes in neurotransmitter levels in the olfactory bulb in response to a trained odor. Using in vivo microdialysis enables measurement of both baseline responsiveness of alcohol-exposed pups as well as learned responses at several different developmental ages. The established neural features of this olfactory model include an increase in behavioral preference for a trained odor, increases in 2-DG uptake in specific foci within the olfactory bulb in response to the odor, and increases in dopamine in response to olfactory preference training stimuli, as well as conditioned increases in norepinephrine following olfactory preference training. Using these known behavioral, metabolic and neurochemical indices in control pups allows identification of some of the neurotransmitter systems involved in deficits and the neurobiological basis for impairments induced by prenatal alcohol exposure.

Ethanol exposure alters the development of serotonergic neurons in chick spinal cord

Exposure to ethanol is known to alter the development of the serotonergic system. However, previous studies have examined large populations of cells and have not determined the effects of ethanol on individual serotonergic neurons. In the present study, the effects of various concentrations of ethanol on the development of single serotonergic neurons in the chick embryo spinal cord were determined using immunohistochemical techniques. Between embryonic day 7 (E7) and E14, ethanol administrations produced in ovo alcohol concentrations of: a) low dose, 30-60 mg/dl, b) medium dose, 150-200 mg/dl or c) high dose, 240-300 mg/dl. In animals exposed to the medium and high ethanol doses, the normal developmental increase in cross-sectional area of the somata was not observed. At all stages examined, the numbers of primary and nonprimary processes were significantly lower in ethanol-treated groups compared to controls. These data indicate that ethanol exposure induces dose-dependent alterations in the development of identified spinal cord neurons. The ethanol-induced changes may be involved in the motor dysfunction observed after embryonic ethanol exposure.

Autistic behaviors in offspring of mothers abusing alcohol and other drugs: a series of case reports

Although autistic-like behaviors were described even in the earliest reports of fetal alcohol syndrome, it was only recently that fetal alcohol syndrome and autism were reported as a dual diagnosis in six school-aged children. The purpose of the present series of case reports is to describe marked autistic characteristics in three much younger children (25-36 months) with histories of prenatal exposure to alcohol and other drugs. The behavioral characteristics of these children are described and compared with current diagnostic criteria for autistic disorder. In addition, longitudinal scores on the Bayley Scales of Infant Development are provided to underscore the marked developmental delays shown by each of the children. Limitations of these case reports are discussed with suggestions for future prospective research.

Children Exposed to Drugs in Utero: Their Scores on the Miller Assessment for Preschoolers

This article presents findings from a retrospective study of 54 children who were prenatally exposed to drugs and who received the Miller Assessment for Preschoolers as part of a developmental follow-up clinic protocol. Data were analyzed using nonparametric descriptive statistics to examine trends in the test scores compared to the test norms and to determine if a distinctive clinical profile was present. Although a distinctive clinical profile did not emerge, the overall test results indicated a skewness toward the lower end of the spectrum with poorer performance identified on test items measuring tactile, proprioceptive and vestibular processing, and language. Performance of items that assessed aspects of non-verbal cognition tended to be within the normal range. The difficulties of conducting studies within this group of children are discussed.

Prenatal ethanol exposure: susceptibility to convulsions and ethanol's anticonvulsant effect in amygdala-kindled rats

The present experiments assessed the effects of prenatal ethanol exposure on the susceptibility to convulsions and on the anticonvulsant effect of ethanol using the electrical kindling model of epilepsy in rats. Adult male Sprague-Dawley rats from prenatal ethanol (E), pair-fed (PF), and ad libitum-fed control (C) treatment groups were tested following the implantation of a stimulation electrode in the left amygdala complex. The same rats were tested in four consecutive experiments. Both E and PF rats showed a slightly slower rate of kindling than C rats, as measured by convulsion class but not as measured by forelimb clonus duration (experiment 1). However, the groups did not differ significantly in the electrical stimulation threshold for kindled convulsions (experiment 2). Furthermore, prenatal ethanol exposure had no significant effect on the dose-response curve for ethanol's (0, 0.9, 1.1, 1.3, and 1.5 g/kg, ip) anticonvulsant effect (experiment 3), or on the rate of tolerance development to ethanol's (1.5 g/kg, ip) anticonvulsant effect (experiment 4) on kindled convulsions. Thus, prenatal exposure to ethanol does not appear to have long-term effects on the susceptibility to convulsions or on the anticonvulsant effect of ethanol in adult male rats in the kindling model as used in the present experiments.