Influence of prenatal cocaine exposure on early language development: longitudinal findings from four months to three years of age

The association of prenatal cocaine exposure with expressive and receptive language skills, phonological processing and reading ability at age 17

OBJECTIVE

Prenatal cocaine exposure (PCE) has been associated with small but significant effects on language development in childhood and early adolescence. This study examined whether this association persists into later adolescence and what relationship language skills may have with reading proficiency in this population.

METHODS

Enrolled were 338 (167 with PCE, 171 with NCE or no cocaine exposure) 17-year-olds recruited at birth who, together with their current caregiver, were seen as part of a 17-year follow-up. Participants were given assessments of reading achievement (WIAT-III), receptive and expressive language (CELF-IV), and phonological processing (CTOPP). Relationships between PCE status and language outcomes were modeled using multiple linear regression controlling for environmental and caregiver factors, and other prenatal substance exposures.

RESULTS

Adolescents with PCE scored lower in areas of phonological processing and reading related skills compared to adolescents with NCE. PCE by sex interactions were identified on language, memory and spoken language comprehension, with lower scores for girls with PCE compared to girls with NCE.

CONCLUSION

These findings suggest the persistence of PCE's relationship with phonological awareness well into adolescence. PCE was also associated with lower scores on measures of skills related to reading ability, which may be a manifestation of the observed deficits in phonological processing.

Identification, diagnosis, and early intervention of children with developmental language disorder in Ningxia

BACKGROUND

It is reported that the incidence of language development disorder in children at the age of 2 is as high as 17.0%. Timely discovery of the high-risk factors of language development disorder in children and early intervention can greatly reduce the incidence of language development disorder and shorten the course and condition of the patients with language development disorder. Therefore, in order to facilitate prompt diagnosis and early interventions for children with language development disorder (DLD) and improve their language ability, this study explored the influence of perinatal factors on the language development of children in Ningxia and identified the unfavorable and favorable factors that influenced language development.

METHODS

Children diagnosed in the General Hospital of Ningxia Medical University during 2018-2021 who met the screening criteria for DLD and practical pediatric diagnostic criteria for DLD were enrolled in this study. Perinatal factors (gestational age, weight, sex, delivery mode, maternal age, presence of intrauterine infection, asphyxia) were retrospectively analyzed. The perinatal factors affecting language development were assessed using a one-way analysis of variance (ANOVA).

RESULTS

Among 1,500 children aged 0-3, 240 cases (16.00%) had language delay. Of these, 122 were male and 118 were female. There were 115 cases of comprehension and expression disorder, 30 cases of articulation disorder, and 90 cases of mixed manifestation. And there were 194 cases with definite intrauterine and perinatal high-risk factors or neonatal diseases, accounting for 80.83% of the total number of children with language delay.

CONCLUSIONS

In Ningxia, factors in the neonatal period are the main cause of DLD, followed by fetal and maternal factors. Ischemic encephalopathy is the most common factor.

Neonatal White Matter Maturation Is Associated With Infant Language Development

BACKGROUND

While neonates have no sophisticated language skills, the neural basis for acquiring this function is assumed to already be present at birth. Receptive language is measurable by 6 months of age and meaningful speech production by 10-18 months of age. Fiber tracts supporting language processing include the corpus callosum (CC), which plays a key role in the hemispheric lateralization of language; the left arcuate fasciculus (AF), which is associated with syntactic processing; and the right AF, which plays a role in prosody and semantics. We examined if neonatal maturation of these fiber tracts is associated with receptive language development at 12 months of age.

METHODS

Diffusion-weighted imaging (DWI) was performed in 86 infants at 26.6 ± 12.2 days post-birth. Receptive language was assessed via the MacArthur-Bates Communicative Development Inventory at 12 months of age. Tract-based fractional anisotropy (FA) was determined using the NA-MIC atlas-based fiber analysis toolkit. Associations between neonatal regional FA, adjusted for gestational age at birth and age at scan, and language development at 12 months of age were tested using ANOVA models.

RESULTS

After multiple comparisons correction, higher neonatal FA was positively associated with receptive language at 12 months of age within the genu (p < 0.001), rostrum (p < 0.001), and tapetum (p < 0.001) of the CC and the left fronto-parietal AF (p = 0.008). No significant clusters were found in the right AF.

CONCLUSION

Microstructural development of the CC and the AF in the newborn is associated with receptive language at 12 months of age, demonstrating that interindividual variation in white matter microstructure is relevant for later language development, and indicating that the neural foundation for language processing is laid well ahead of the majority of language acquisition. This suggests that some origins of impaired language development may lie in the intrauterine and potentially neonatal period of life. Understanding how interindividual differences in neonatal brain maturity relate to the acquisition of function, particularly during early development when the brain is in an unparalleled window of plasticity, is key to identifying opportunities for harnessing neuroplasticity in health and disease.

A better approach to in vivo developmental neurotoxicity assessment: Alignment of rodent testing with effects seen in children after neurotoxic exposures

High throughput screens for developmental neurotoxicity (DN) will facilitate evaluation of chemicals and can be used to prioritize those designated for follow-up. DN is evaluated under different guidelines. Those for drugs generally include peri- and postnatal studies and juvenile toxicity studies. For pesticides and commercial chemicals, when triggered, include developmental neurotoxicity studies (DNT) and extended one-generation reproductive toxicity studies. Raffaele et al. (2010) reviewed 69 pesticide DNT studies and found two of the four behavioral tests underperformed. There are now many epidemiological studies on children showing adverse neurocognitive effects, yet guideline DN studies fail to assess most of the functions affected in children; nor do DN guidelines reflect the advances in brain structure-function relationships from neuroscience. By reducing the number of test ages, removing underperforming tests and replacing them with tests that assess cognitive abilities relevant to children, the value of DN protocols can be improved. Testing for the brain networks that mediate higher cognitive functions need to include assessments of working memory, attention, long-term memory (explicit, implicit, and emotional), and executive functions such as cognitive flexibility. The current DNT focus on what can be measured should be replaced with what should be measured. With the wealth of data available from human studies and neuroscience, the recommendation is made for changes to make DN studies better focused on human-relevant functions using tests of proven validity that assess comparable functions to tests used in children. Such changes will provide regulatory authorities with more relevant data.

Cocaine-induced neurodevelopmental deficits and underlying mechanisms

Exposure to drugs early in life has complex and long-lasting implications for brain structure and function. This review summarizes work to date on the immediate and long-term effects of prenatal exposure to cocaine. In utero cocaine exposure produces disruptions in brain monoamines, particularly dopamine, during sensitive periods of brain development, and leads to permanent changes in specific brain circuits, molecules, and behavior. Here, we integrate clinical studies and significance with mechanistic preclinical studies, to define our current knowledge base and identify gaps for future investigation. Birth Defects Research (Part C) 108:147-173, 2016. © 2016 Wiley Periodicals, Inc.

Language outcomes at 12 years for children exposed prenatally to cocaine

PURPOSE

In this study, the authors aimed to examine the long-term effects of prenatal cocaine exposure (PCE) on the language development of 12-year-old children using a prospective design, controlling for confounding prenatal drug exposure and environmental factors.

METHOD

Children who were exposed to cocaine in utero (PCE; n = 183) and children who were not exposed to cocaine (i.e., no cocaine exposure [NCE]; n = 181) were followed prospectively from birth to 12 years of age and were compared on language subtests of the Test of Language Development-Intermediate, Third Edition ( Hammill & Newcomer, 1997b), and phonological processing as measured by the Comprehensive Test of Phonological Processing ( Wagner & Torgesen, 1999). The authors evaluated the relationship of PCE to language development through a multivariate analysis of covariance and regression analyses while controlling for confounders.

RESULTS

Results show that PCE has small effects on specific aspects of language, including syntax and phonological processing. The caregiver variables of lower maternal vocabulary, more psychological symptoms, and a poorer home environment also had consistent effects on language and phonological processing scores.

CONCLUSIONS

These findings suggest that PCE continues to have small, subtle effects on specific aspects of language at age 12 years. Phonological processing skills were significantly related to the reading outcomes of letter-word identification, reading fluency, and reading comprehension, indicating that PCE also has small but lasting effects on the language skills that are related to later literacy skills.

Street drug use during pregnancy: potential programming effects on preschool wheeze

Street drug use during pregnancy is detrimental to fetal development. Although the prevalence of wheeze is high in offspring of substance-abusing mothers, nothing is known about the role of street drug use during pregnancy in its development. We investigated the impact of maternal street drug use and distress during pregnancy on the development of wheeze and allergy in preschool children. Questionnaire data were accessed from the Community Perinatal Care trial of 791 mother–child pairs in Calgary, Alberta. Using logistic regression, the association between maternal substance use and distress during pregnancy, and wheeze and allergy at age 3 years was determined in boys and girls. After adjusting for alcohol use during pregnancy, pre- and postnatal tobacco use, preterm birth, duration of exclusive breastfeeding, daycare attendance and maternal socioeconomic status, maternal street drug use during pregnancy [odds ratio (OR): 5.02, 95% confidence interval (CI): 1.30–19.4] and severe maternal distress during pregnancy (OR: 5.79, 95% CI: 1.25–26.8) were associated with wheeze in girls. In boys, an independent association was found between severe distress during pregnancy (OR: 3.85, 95% CI: 1.11–13.3) and allergies, but there was no association with maternal street drug use. In conclusion, we found an association between maternal street drug use and wheeze in preschool girls that could not be accounted for by maternal distress, smoking or alcohol use during pregnancy. Prenatal programming effects of street drugs may explain this association.

Developmental and behavioral consequences of prenatal cocaine exposure: a review

Substance use among pregnant women continues to be a major public health concern, posing potential risk to their drug-exposed children as well as burdens on society. This review is intended to discuss the most recent literature regarding the association between in utero cocaine exposure and developmental and behavioral outcomes from birth through adolescence across various domains of functioning (growth, neurobiology, intelligence, academic achievement, language, executive functioning, behavioral regulation and psychopathology). In addition, methodological limitations, associated biological, sociodemographic and environmental risk factors and future directions in this area of research are discussed. Given the large number of exposed children in the child welfare system and the increased need for medical, mental health and special education services within this population, more definitively documenting associations between prenatal cocaine exposure and later child outcomes is essential in order to be able to prospectively address the many significant public health, economic and public policy implications.

Prenatal IV Cocaine: Alterations in Auditory Information Processing

One clue regarding the basis of cocaine-induced deficits in attentional processing is provided by the clinical findings of changes in the infants' startle response; observations buttressed by neurophysiological evidence of alterations in brainstem transmission time. Using the IV route of administration and doses that mimic the peak arterial levels of cocaine use in humans, the present study examined the effects of prenatal cocaine on auditory information processing via tests of the auditory startle response (ASR), habituation, and prepulse inhibition (PPI) in the offspring. Nulliparous Long-Evans female rats, implanted with an IV access port prior to breeding, were administered saline, 0.5, 1.0, or 3.0 mg/kg/injection of cocaine HCL (COC) from gestation day (GD) 8-20 (1×/day-GD8-14, 2×/day-GD15-20). COC had no significant effects on maternal/litter parameters or growth of the offspring. At 18-20 days of age, one male and one female, randomly selected from each litter displayed an increased ASR (>30% for males at 1.0 mg/kg and >30% for females at 3.0 mg/kg). When reassessed in adulthood (D90-100), a linear dose-response increase was noted on response amplitude. At both test ages, within-session habituation was retarded by prenatal cocaine treatment. Testing the females in diestrus vs. estrus did not alter the results. Prenatal cocaine altered the PPI response function across interstimulus interval and induced significant sex-dependent changes in response latency. Idazoxan, an α(2)-adrenergic receptor antagonist, significantly enhanced the ASR, but less enhancement was noted with increasing doses of prenatal cocaine. Thus, in utero exposure to cocaine, when delivered via a protocol designed to capture prominent features of recreational usage, causes persistent, if not permanent, alterations in auditory information processing, and suggests dysfunction of the central noradrenergic circuitry modulating, if not mediating, these responses.

Substance use and women's health

Scientific findings show that substance abuse in women yields a higher risk of a variety of health problems than substance abuse in men. Research suggests that women experience addiction telescoping when they abuse alcohol, tobacco, specific stimulants, and possibly opioids. Medical side effects also develop more rapidly in women than men when they abuse many substances. Cancer and cardiac complications, specifically, pose a significant threat for women who abuse almost all types of substances. However, the physical consequences are not the only ones women suffer when they engage in substance abuse. Research on substance abuse in women ties opioids to mood and anxiety disorders, heroin to neurological deficiencies, cocaine to immune system suppression, and alcohol to intimate partner abuse. Additionally, female substance abusers, on average, have a lower level of education and lower rates of employment. In light of these gender-specific concerns, physicians should give particular consideration to detecting substance abuse in women.

Prenatal drug exposure: infant and toddler outcomes

This manuscript provides an overview of the current scientific literature on the impact of maternal drug use, specifically opioids and cocaine, during pregnancy on the acute and long-term outcomes of infants and toddlers from birth through age 3 years. Emphasis with regard to opioids is placed on heroin and opioid substitutes used to treat opioid addiction, including methadone, which has long been regarded as the standard of care in pregnancy, and buprenorphine, which is increasingly being investigated and prescribed as an alternative to methadone. Controlled studies comparing methadone at high and low doses, as well as those comparing methadone with buprenorphine, are highlighted and the diagnosis and management of neonatal abstinence syndrome is discussed. Over the past two decades, attention of the scientific and lay communities has also been focused on the potential adverse effects of cocaine and crack cocaine, especially during the height of the cocaine epidemic in the United States. Herein, the findings are summarized from prospective studies comparing cocaine-exposed with non-cocaine-exposed infants and toddlers with respect to anthropometric growth, infant neurobehavior, visual and auditory function, and cognitive, motor, and language development. The potentially stigmatizing label of the so-called "crack baby" preceded the evidence now accumulating from well-designed prospective investigations that have revealed less severe sequelae in the majority of prenatally exposed infants than originally anticipated. In contrast to opioids, which may produce neonatal abstinence syndrome and infant neurobehavioral deficits, prenatal cocaine exposure appears to be associated with what has been described as statistically significant but subtle decrements in neurobehavioral, cognitive, and language function, especially when viewed in the context of other exposures and the caregiving environment which may mediate or moderate the effects. Whether these early findings may herald more significant learning and behavioral problems during school-age and adolescence when the child is inevitably confronted with increasing social and academic challenges is the subject of ongoing longitudinal research.

The effects of prenatal cocaine on language development at 10 years of age

OBJECTIVE

To examine the long term effects of prenatal cocaine exposure (PCE) on the language development of 10-year-old children utilizing a prospective design, controlling for confounding drug and environmental factors.

PARTICIPANTS

Children exposed to cocaine in utero (PCE; n=175) and non-exposed children (NCE; n=175) were followed prospectively to 10years of age and were compared on language subscales of the Test of Language Development-Intermediate 3rd Edition (TOLD-I:3) and phonological processing as measured by the Comprehensive Test of Phonological Processing (CTOPP).

METHODS

Multivariate analysis of covariance (MANCOVA), linear regression, and logistic regressions were used to evaluate the relationship of prenatal cocaine exposure to language development, while controlling for confounders.

RESULTS

After controlling for confounding variables, prenatal cocaine effects were observed for specific aspects of language including syntax (Sentence Combining subtest of the TOLD-I:3, p=0.001), semantics (Malopropism subtest of the TOLD-I:3, p=0.05) and phonological processing (Phonological Awareness subscale, p=0.01). The caregiver factors of vocabulary, HOME, and psychological symptoms also had consistent effects on language subtests and phonological processing scores. Children with PCE who experienced foster or adoptive care had enhanced language development compared to those living with birth mothers or in relative care. Cocaine exposed girls had lower scores on the phonological awareness subscale of the CTOPP than non-exposed girls.

CONCLUSIONS

PCE has subtle effects on specific aspects of language development and phonological processing at age 10, even after controlling for confounding variables. Environmental factors (i.e., postnatal lead exposure, home environment, and caregiver vocabulary and psychological symptoms) also impact language skills at 10years. Adoptive or foster care appears to enrich PCE children's linguistic environment and protects children against language delay in the PCE sample.

Expression of the nociceptin receptor during zebrafish development: influence of morphine and nociceptin

The NOP system is considered to be part of the opioid system, although it exerts antiopioid actions depending on the anatomical region where it is localized. This apparent controversy has lead to the hypothesis that the NOP system interacts with the classical opioid systems (mu, delta, kappa) and regulates/modulates their activity in relation to analgesia and the development of addiction to drugs. In order to shed light into the importance of the NOP system, we have analyzed the expression of NOP during zebrafish development, and the effect of its endogenous agonist nociceptin and the opioid agonist morphine on NOP expression. Our qPCR study show that the number of NOP transcripts is different at each developmental stage studied (0.5 hpf, 2.75 hpf, 3 hpf, 8 hpf, 16 hpf, 19 hpf, 22 hpf, 24 hpf, 30 hpf, 48 hpf, 60 hpf and 72 hpf). Nociceptin enhances NOP expression at 24 hpf but decreases the number of NOP copies at 48 hpf, whereas NOP expression decreases after morphine exposure at 24 hpf and 48 hpf. Also, our ISH analysis demonstrates that nociceptin causes a change in the distribution of NOP towards rostral areas at both developmental stages. Morphine produces similar changes to those of nociceptin although only at 48 hpf. The present work leads to the conclusion that the NOP system is important during embryogenesis. Exposure to drugs changes the expression level and localization of NOP, suggesting that also during development, NOP plays a role in the apparition of dependence and addiction to drugs.

Effects of prenatal cocaine exposure on special education in school-aged children

OBJECTIVE

The objective of this study was to evaluate the effects of prenatal cocaine exposure on special education at age 7 with adjustment for covariates.

METHODS

As part of the prospective, longitudinal, multisite study of children with prenatal cocaine exposure (Maternal Lifestyle Study), school records were reviewed for 943 children at 7 years to determine involvement in special education outcomes: (1) individualized education plan; (2) special education conditions; (3) support services; (4) special education classes; and (5) speech and language services. Logistic regression was used to examine the effect of prenatal cocaine exposure on these outcomes with environmental, maternal, and infant medical variables as covariates, as well as with and without low child IQ.

RESULTS

Complete data for each analysis model were available for 737 to 916 children. When controlling for covariates including low child IQ, prenatal cocaine exposure had a significant effect on individualized education plan. When low child IQ was not included in the model, prenatal cocaine exposure had a significant effect on support services. Male gender, low birth weight, white race, and low child IQ also predicted individualized education plan. Low birth weight and low child IQ were significant in all models. White race was also significant in speech and language services. Other covariate effects were model specific. When included in the models, low child IQ accounted for more of the variance and changed the significance of other covariates.

CONCLUSIONS

Prenatal cocaine exposure increased the likelihood of receiving an individualized education plan and support services, with adjustment for covariates. Low birth weight and low child IQ increased the likelihood of all outcomes. The finding that white children were more likely to get an individualized education plan and speech and language services could indicate a greater advantage in getting educational resources for this population.

Neighborhood and individual factors in marijuana and other illicit drug use in a sample of low-income women

Few studies have systematically evaluated whether contextual variables differ in their ability to explain the use of different drugs in the same sample. Our objective was to examine correlates of use for different illicit drugs at the individual and neighborhood level in a tri-ethnic sample of low-income women, an underrepresented sample in drug research. Women 18-31 were recruited from a low-cost family planning clinic in southeast Texas from December 2001 to May 2003. Neighborhood level indicators of disadvantage, family structure, and nativity status from U.S. Census 2000 were linked with individual survey data. Multilevel logistic regression was used to examine the effect of individual and neighborhood level measures on lifetime use of marijuana only and of other illicit drugs in 594 women. Only individual level variables (younger age, non-Hispanic White ethnicity, not being married, greater peer acceptance of substance use) increased odds of exclusive marijuana use, controlling for neighborhood level factors. However, both neighborhood and individual level variables significantly predicted other illicit drug use. Residence in less disadvantaged neighborhoods, non-Hispanic White ethnicity, higher levels of education, greater acceptance of substance use by peers, and a larger number of perceived neighborhood problems increased odds of illicit drug use. Use of other illicit drugs with or without marijuana may be more closely tied to area level factors whereas factors driving exclusive marijuana use may not rely on localized structures to the same extent. Thus, community-level interventions may need to customize their approaches according to the type of drug use targeted. The implication of using neighborhood level variables in substance use research is also discussed.

A meta-analysis of animal studies on disruption of spatial navigation by prenatal cocaine exposure

Water-maze testing has been used to assess prenatal cocaine (PCOC)-induced deficits in behavioral studies of spatial navigation and memory abilities. Effects of PCOC in acquisition or in probe trials over water-maze testing days were rarely detected. Despite an absence of effects of PCOC when data were collapsed over multiple days, there was a potential difference when examined during the first day of acquisition training, characterized by a PCOC-associated decrease in learning efficiency but not capacity. Here, we review studies of PCOC-related changes in day-1 water-maze acquisition training and examine the relationship between experimental methodologies and PCOC-treatment procedures and the variability in effect size estimates across studies. The results revealed a significant increase in latencies to goal platform on acquisition training day-1 in PCOC-exposed offspring vs. controls (effect size: r=0.44). Significant effects attributable to variations in the PCOC-treatment procedures across studies were also identified. The moderating variable of PCOC "dose" was significant as lower doses of PCOC exposure yielded larger treatment effects. "Duration" of PCOC exposure was not significant, although a trend for greater effects was observed in studies that employed longer daily treatment schedules or schedules administered in later gestational periods. This analysis identified a consistent difference in acquisition training day-1 of water-maze testing in PCOC-exposed offspring indicating a PCOC-induced deficiency in spatial learning. These findings of impaired spatial learning efficiency are of particular interest given clinical scenarios involving acutely impaired spatial memory and related learning in PCOC-exposed children that highlight the potential consequences in classroom learning.

Prenatal cocaine and tobacco effects on children's language trajectories

OBJECTIVE

The objective of this study was to examine the effects of prenatal cocaine and polydrug exposure on language development of preschool children using a prospective longitudinal model, controlling for confounders.

METHODS

Children who were exposed to cocaine in utero (n = 209) and nonexposed children (n = 189) were followed prospectively at birth and at 1, 2, 4, and 6 years of age and were compared on receptive, expressive, and total language scores across time using random coefficient models, controlling for confounders.

RESULTS

A significant, stable effect of cocaine exposure on language development was observed over time for all language domains, with cocaine exposure related to poorer language performance. Cigarette exposure was related to lower receptive language scores. Environmental influences on language scores were also observed. Both the cocaine-exposed and nonexposed children declined in language performance over time.

CONCLUSIONS

Prenatal cocaine exposure has a stable negative effect on language skills during the first 6 years of life. Both cocaine-exposed and nonexposed children showed decreased language growth over time; however, cocaine-exposed children demonstrated linguistic deficits compared with nonexposed peers and did not catch up. Cigarette and environmental influences were also noted.

Learning disabilities and intellectual functioning in school-aged children with prenatal cocaine exposure

Risk for developing a learning disability (LD) or impaired intellectual functioning by age 7 was assessed in full-term children with prenatal cocaine exposure drawn from a cohort of 476 children born full term and enrolled prospectively at birth. Intellectual functioning was assessed using the Wechsler Intelligence Scale for Children-Third Edition (Wechsler, 1991) short form, and academic functioning was assessed using the Wechsler Individual Achievement Test (WIAT; Wechsler, 1993) Screener by examiners blind to exposure status. LDs were categorized based on ability-achievement discrepancy scores, using the regression-based predicted achievement method described in the WIAT manual. The sample in this report included 409 children (212 cocaine-exposed, 197 non-cocaine-exposed) from the birth cohort with available data. Cumulative incidence proportions and relative risk values were estimated using STATA software (Statacorp, 2003). No differences were found in the estimate of relative risk for impaired intellectual functioning (IQ below 70) between children with and without prenatal cocaine exposure (estimated relative risk = .95; 95% confidence interval [CI] = 0.65, 1.39; p = .79). The cocaine-exposed children had 2.8 times greater risk of developing a LD by age 7 than non-cocaine-exposed children (95% CI = 1.05, 7.67; p = .038; IQ >/= 70 cutoff). Results remained stable with adjustment for multiple child and caregiver covariates, suggesting that children with prenatal cocaine exposure are at increased risk for developing a learning disability by age 7 when compared to their non-cocaine-exposed peers.

School-age outcome of children with prenatal cocaine exposure following early case management

The impact of prenatal cocaine exposure on neurodevelopmental outcome in childhood continues to be in question. Objectives of this study were to determine if there are differences in growth, behavioral, cognitive or verbal functioning or caregiver-child dyad interactions for inner-city, school-aged children with and without prenatal cocaine exposure, and if these measures would be affected by early family case management. From an initial sample of 118 cocaine-exposed children who were evaluated to 36 months of age, 47 were able to be contacted and 39 (83%) completed a follow-up evaluation at 84 +/- 11 months of age. Subjects had been assigned at birth to early case management (CM, 24) and routine care (RC, 15). Eighteen children from the initial non-cocaine-exposed comparison sample of 41 children were able to be contacted and 12 (67%) were evaluated at 85 +/- 16 months of age. Evaluation included growth measurements, Stanford-Binet IQ, receptive and expressive language quotients, parent-reported Child Behavior Checklists (CBCL), and assessment of caregiver-child interactions by scored videotaped free-play sessions. No differences were found in growth, mean IQ, language quotients, CBCL scores or videotaped caregiver-child play interactions as a function of cocaine exposure. Within the cocaine-exposed group, there were no outcome differences between CM and RC children. However, during the play sessions, CM caregivers had more positive affect in interactions with the child than RC. Within the RC dyads, birthmothers had significantly more positive interactions than non-birthmothers. In summary, no differences in growth, behavioral, cognitive, or language function were evident for inner-city, school-aged children related to prenatal cocaine exposure or early case management. CM caregivers demonstrated more positive interactions during a play session than RC; within the RC group, non birthmothers had the least positive affective interactions. Further study of influences on caregiver-child interactions may lead to effective intervention strategies for drug-exposed infants.

Effects of prenatal cocaine, morphine, or both on postnatal opioid (μ) receptor development

We studied the effects of prenatal cocaine and morphine given separately and in combination on the (1) postnatal brain mu-opioid receptor development and (2) interaction of dopamine with mu receptors. Pregnant rats received single daily intraperitoneal (I.P.) injections of saline, cocaine (20 mg/kg), morphine (2 mg/kg), or the combination of both drugs from day 13 to day 20 of gestation. Postnatal days (P) 1, 7, 14, and 28, whole brains were analyzed for opioid receptor binding and mu mRNA. Prenatal cocaine administered by itself had no significant effect on the ontogeny of brain mu receptors on all the days studied when compared to controls. The morphine-treated group showed a significant increase in mu receptor binding on P1 and P7. Exposure to both cocaine and morphine showed a significant increase in mu receptor density on P1 and P7. In addition, there was also a significant increase in MOR mRNA in both the morphine alone and combination groups. Pretreatment with dopamine D2 receptor antagonist (sulpiride, 20 mg/kg) prior to drug administration showed decreased mu receptor binding on P1 and P7. These results suggest that prenatal exposure to morphine or a combination of cocaine and morphine significantly increases mu receptor density. By P14, mu-opioid receptor binding was no longer different than the control. This may suggest that the effect on receptor may be short-lived and that other key intracellular events may be activated to mediate the long-term effects. Also, the data show that dopaminergic mechanisms are (or opioid-dopamine interaction is) involved in the effects of morphine alone or morphine in combination with cocaine on mu receptor regulation.

Prenatal cocaine exposure and children's language functioning at 6 and 9.5 years: moderating effects of child age, birthweight, and gender

OBJECTIVE

To evaluate whether prenatal cocaine exposure (PCE), or the interaction between PCE and contextual variables, is associated with children's language at age 6 and 9.5 years, adjusting for relevant covariates.

METHODS

Analyses were based on 160 low-income, urban children from a prospective study who completed a standardized language assessment at 6 and 9.5 years. PCE was determined using neonatal meconium assays and maternal self-report.

RESULTS

Significant interaction effects of PCE on language outcomes were found in multivariate longitudinal analyses using generalized estimating equations (GEE). Children with PCE had lower receptive language than unexposed children at 6 but not at 9.5 years, lower expressive language if they had lower birthweight, and lower expressive and total language if they were female. Other risk (e.g., violence exposure) and protective factors (e.g., preschool experience) were related to language outcomes regardless of PCE status.

CONCLUSIONS

Age, birthweight, and gender moderated the relation between PCE and school-aged children's language.

Prenatal cocaine exposure specifically alters spontaneous alternation behavior

Our laboratory has previously characterized a rabbit model of gestational cocaine exposure in which permanent alterations in neuronal morphology, cell signaling and psychostimulant-induced behavior are observed. The cellular and molecular neuroadaptations produced by prenatal cocaine occur in brain regions involved in executive function and attention, such as the anterior cingulate and medial prefrontal cortices. Therefore, in the present study, we have measured the effects of prenatal cocaine exposure on specific behavioral tasks in adult offspring whose mothers were treated with cocaine (3mg/kg, twice a day, E16-E25). We assessed non-spatial, short-term memory in a two-object recognition task and found no deficits in memory or exploratory behaviors in cocaine-exposed offspring in this paradigm. We also evaluated a different memory task with a more robust attentional component, using spontaneous alternation in a Y maze. In this task, young adult rabbits exposed to cocaine prenatally exhibited a significant deficit in performance. Deficits in spontaneous alternation can be induced by a wide variety of behavioral and cognitive dysfunctions, but taken together with previous findings in this and other animal models, we hypothesize that prenatal exposure to cocaine alters highly specific aspects of cognitive and emotional development.

Prenatal alcohol and cocaine exposure: influences on cognition, speech, language, and hearing

This paper reviews research on the consequences of prenatal exposure to alcohol and cocaine on children's speech, language, hearing, and cognitive development. The review shows that cognitive impairment, learning disabilities, and behavioral disorders are the central nervous system manifestations of fetal alcohol syndrome (FAS), and cranio-facial abnormalities are also present. Delays in language acquisition, as well as receptive and expressive language deficits, are commonly reported. The cranio-facial abnormalities of FAS, which sometimes include cleft palate, make the child prone to otitis media with effusion and conductive hearing loss. The family environment in which one or both parents is a heavy alcohol user presents challenges to a child with normal intelligence, but may be especially deleterious to the child with mental retardation. Prenatal exposure to cocaine results in subtle cognitive disabilities when measured at 4 years of age. The cognitive effects may be ameliorated by a stimulating and sensitive care-giving environment. A small, deleterious "cocaine-effect" is also seen in speech and language development. The child with prenatal exposure to cocaine may be considered at increased risk for language delay or disorder. There is no evidence that prenatal cocaine exposure by itself is a risk factor for sensorineural hearing impairment, although auditory evoked potentials from the brainstem and cortex suggest some abnormalities in central auditory processing, at least during the newborn period. The strong effect of the home environment for ameliorating the effects of prenatal cocaine-exposure suggests that a family-focused approach for cognitive, language, and social-emotional habilitation would be beneficial to all.

LEARNING OUTCOMES

The learner will be able to describe the major features of fetal alcohol syndrome and how they relate to speech, language, hearing, and cognitive disorders. The learner will review the literature and determine research needs with respect to language, speech, and hearing among infants and children with fetal alcohol syndrome. Similarly, the learner will distinguish the outcomes of prenatal alcohol-exposure from those of prenatal cocaine-exposure. The learner will summarize the controversy regarding the possible stigmatization of cocaine-exposed infants. The learner will summarize the speech, language, and hearing effects of prenatal cocaine-exposure.

Expressive and receptive language functioning in preschool children with prenatal cocaine exposure

OBJECTIVE

To estimate the relationship between severity of prenatal cocaine exposure and expressive and receptive language skills in full-term, African American children at age 3 years.

METHODS

Language was assessed at age 3 using the Clinical Evaluation of Language Fundamentals-Preschool (CELF-P). The sample included 424 children (226 cocaine exposed, 198 non-cocaine exposed) who received preschool language assessments at age 3, drawn from a cohort of 476 children enrolled prospectively at birth.

RESULTS

Structural equation modeling was used to regress expressive and receptive language as intercorrelated response variables on level of prenatal cocaine exposure, measured by a latent construct including maternal self-report of cocaine use and maternal/infant urine toxicology assays and infant meconium. Results indicated a.168 SD decrease in expressive language functioning for every unit increase in exposure level (95% CI = -.320, -.015; p =.031) after consideration for fetal growth and gestational age as correlated response variables. Receptive language was more modestly related to prenatal cocaine exposure and was not statistically significant. Results for expressive language remained stable with inclusion of the McCarthy general cognitive index as a response variable (expressive language beta = -.173, 95% CI = -.330, -.016; p =.031), and with adjustment for maternal age and prenatal exposures to alcohol, tobacco, and marijuana (expressive language beta = -.175, 95% CI = -.347, -.003; p =.046). Additional child and caregiver environmental variables assessed at age 3 were also evaluated in varying statistical models with similar results.

CONCLUSION

The evidence from this study supports a gradient relationship between increased level of prenatal cocaine exposure and decreased expressive language functioning in preschool-aged cocaine-exposed children.

Prenatal cocaine exposure: a comparison of 2-year-old children in parental and nonparental care

Effects of prenatal cocaine exposure and parental versus nonparental care on outcome at 2 years of age were examined. The sample included 83 cocaine-exposed and 63 nonexposed children and their caregivers; 49 and 34 of the cocaine-exposed children experienced parental and nonparental care, respectively. Prenatal drug exposure was not related directly to children's outcome at 2 years of age. However, compared with cocaine-exposed children in parental care, those in nonparental care experienced a more optimal environment and performed better in several developmental domains at 2 years of age in spite of being at greater neonatal risk. Further analyses suggested that this protective effect of nonparental care was in part due to nonkin rather than kin care.

Severity of prenatal cocaine exposure and child language functioning through age seven years: a longitudinal latent growth curve analysis

The current study estimates the longitudinal effects of severity of prenatal cocaine exposure on language functioning in an urban sample of full-term African-American children (200 cocaine-exposed, 176 noncocaine-exposed) through age 7 years. The Miami Prenatal Cocaine Study sample was enrolled prospectively at birth, with documentation of prenatal drug exposure status through maternal interview and toxicology assays of maternal and infant urine and infant meconium. Language functioning was measured at ages 3 and 5 years using the Clinical Evaluation of Language Fundamentals--Preschool (CELF-P) and at age 7 years using the Core Language Domain of the NEPSY: A Developmental Neuropsychological Assessment. Longitudinal latent growth curve analyses were used to examine two components of language functioning, a more stable aptitude for language performance and a time-varying trajectory of language development, across the three time points and their relationship to varying levels of prenatal cocaine exposure. Severity of prenatal cocaine exposure was characterized using a latent construct combining maternal self-report of cocaine use during pregnancy by trimesters and maternal and infant bioassays, allowing all available information to be taken into account. The association between severity of exposure and language functioning was examined within a model including factors for fetal growth, gestational age, and IQ as intercorrelated response variables and child's age, gender, and prenatal alcohol, tobacco, and marijuana exposure as covariates. Results indicated that greater severity of prenatal cocaine exposure was associated with greater deficits within the more stable aptitude for language performance (D = -0.071, 95% CI = -0.133, -0.009; p = 0.026). There was no relationship between severity of prenatal cocaine exposure and the time-varying trajectory of language development. The observed cocaine-associated deficit was independent of multiple alternative suspected sources of variation in language performance, including other potential responses to prenatal cocaine exposure, such as child's intellectual functioning, and other birth and postnatal influences, including language stimulation in the home environment.