We sought to determine the association between small for gestational age (SGA), birth weight, and childhood obesity within preterm polysubstance exposed children. We sampled 312 preterm children with 11-year body mass index (BMI; age- and sex-specific) data from the Maternal Lifestyle Study (51% girls, 21.5% SGA, 46% prenatal cocaine, and 55% tobacco exposed). Multinomial regression analyzed the association between 11-year obesity (OBE) and overweight (OW) and SGA, birth weight, first-year growth velocity, diet, and physical activity variables. Overall, 24% were OBE (BMI for age ≥95th percentile) and 16.7% were OW (BMI ≥85th and <95th percentiles). In adjusted analyses, SGA was associated with OW (odds ratio [OR]=3.4, confidence interval [CI] 1.5 to 7.5). Higher birth weight was associated with OBE (OR = 1.8, CI 1.3 to 2.4) and OW (OR=1.4, CI 1.1 to 2.0). Growth velocity was associated with OBE (OR=2.7, CI 1.8 to 4.0) and OW (OR=1.6, CI 1.1 to 2.4). Low exercise was associated with OBE (OR=2.1, CI 1.0 to 4.4) and OW (OR=2.1, CI 1.0 to 4.5). There was no effect of substance exposure on obesity outcomes. Many (41%) of these high-risk preterm 11-year-olds were obese/overweight. Multiple growth-related processes may be involved in obesity risk for preterm children, including fetal programming as indicated by the SGA effect.
Childhood obesity; premature birth; infant SGA; birth weight; exercise; prenatal drug exposure
To examine the relationships between sleep problems and prenatal exposure to cocaine, opiates, marijuana, alcohol, and nicotine in children 1 month to 12 years of age.
Sleep data was collected by maternal report in a prospective longitudinal follow-up of children participating in the Maternal Lifestyle multisite study.
Hospital based research centers in Providence, RI, Miami, FL, Detroit, MI, and Memphis, TN
There were 808 participants: 374 exposed to cocaine and/or opiates; 434 comparison.
Prenatal cocaine, opiate, marijuana, alcohol, and nicotine exposure.
Sleep problems in early, middle, and late childhood, assessed as composites of maternal report items.
Of the five substances, prenatal nicotine exposure was the only unique predictor of sleep problems (B = .074, R2 Δ = .008, p = .012) with adjustment for covariates including SES, marital status, physical abuse, prenatal medical care, and postnatal cigarette smoke exposure.
Prenatal exposure to nicotine was positively associated with children's sleep problems persisting throughout the first 12 years of life. Targeting this group of children for educational and behavioral efforts to prevent and treat sleep problems is merited given that good sleep may serve as a protective factor for other developmental outcomes.
Prenatal cocaine exposure has been linked to intrauterine growth retardation and poor birth outcomes; little is known about the effects on longer-term medical outcomes, such as overweight status and hypertension in childhood. Our objective was to examine the association between prenatal cocaine exposure and body mass index and blood pressure at 9 years of age among children followed prospectively in a multi-site longitudinal study evaluating the impact of maternal lifestyle during pregnancy on childhood outcome.
This analysis includes 880 children (277 cocaine exposed and 603 with no cocaine exposure) with blood pressure, height, and weight measurements at 9 years of age. Regression analyses were conducted to explore the relationship between prenatal cocaine exposure and body mass index and blood pressure at 9 years of age after controlling for demographics, other drug exposure, birth weight, maternal weight, infant postnatal weight gain, and childhood television viewing, exercise and dietary habits at 9 years. Path analyses were used to further explore these relationships.
At 9 years of age, 15% of the children were pre-hypertensive and 19% were hypertensive; 16% were at risk for overweight status and 21% were overweight. A small percentage of women were exposed to high levels of prenatal cocaine throughout pregnancy. Among children born to these women, a higher body mass index was noted. Path analysis suggested that high cocaine exposure has an indirect effect on systolic and diastolic blood pressure that is mediated through its effect on body mass index.
High levels of in-utero cocaine exposure are a marker for elevated body mass index and blood pressure among children born full term.
Prenatal cocaine exposure; Body mass index; Childhood hypertension; Overweight; Obesity
This study examines the relationship between prenatal cocaine exposure and parent-reported child behavior problems at age 7 years.
Data are from 407 African-American children (210 cocaine-exposed, 197 non-cocaine-exposed) enrolled prospectively at birth in a longitudinal study on the neurodevelopmental consequences of in utero exposure to cocaine. Prenatal cocaine exposure was assessed at delivery through maternal self-report and bioassays (maternal and infant urine and infant meconium). The Achenbach Child Behavior Checklist (CBCL), a measure of childhood externalizing and internalizing behavior problems, was completed by the child’s current primary caregiver during an assessment visit scheduled when the child was seven years old.
Structural equation and GLM/GEE models disclosed no association linking prenatal cocaine exposure status or level of cocaine exposure to child behavior (CBCL Externalizing and Internalizing scores or the eight CBCL sub-scale scores).
This evidence, based on standardized ratings by the current primary caregiver, fails to support hypothesized cocaine-associated behavioral problems in school-aged children with in utero cocaine exposure. A next step in this line of research is to secure standardized ratings from other informants (e.g., teachers, youth self-report).
cocaine; prenatal exposure; child behavior
This study examined the effects of prenatal cocaine exposure, environmental risk, and maternal verbal intelligence on children's cognitive ability. Gender and age were examined as moderators of potential cocaine exposure effects. The Stanford-Binet IV intelligence test was administered to 231 children (91 cocaine exposed, 140 unexposed) at 4, 6, and 9 years of age. Neonatal medical risk and other prenatal exposures (alcohol, cigarettes, and marijuana) were also examined for their unique effects on child IQ. Mixed models analysis indicated that prenatal cocaine exposure interacted with gender as cocaine exposed boys had lower composite IQ scores. Age of assessment did not moderate this relation, indicating that cocaine exposed boys had lower IQs across this age period. A stimulating home environment and high maternal verbal IQ also predicted higher composite IQ scores. Cocaine exposed boys had lower scores on the Abstract/Visual Reasoning subscale, with trends for lower scores on the Short-term Memory and Verbal Reasoning subscales, as exposure effects were observed across domains. The findings indicate that cocaine exposure continues to place children at risk for mild cognitive deficits into preadolescence. Possible mechanisms for the exposure by gender interaction are discussed.
prenatal cocaine exposure; environmental risk; gender differences; intelligence
To evaluate the impact of prenatal cocaine exposure and small-for-gestational-age (SGA) status on childhood growth.
Cocaine exposure was defined by history or meconium metabolites. Hierarchical linear modeling was used to examine cocaine exposure and SGA status on growth, while controlling for exposure to other drugs and alcohol use.
At birth cocaine-exposed infants (n=364) had significantly lower growth parameters compared to non-exposed children (n=771). At 6 years, weight was similar between exposed and unexposed children. SGA infants continued to be growth impaired. There was a significant interaction between prenatal cocaine exposure and SGA status at 6 years. The negative effects of cocaine on weight and height were greater among non-SGA than SGA children (432 vs. 280 gm, and 0.7 and 0.5 cm, respectively) while negative effects of SGA status on weight and height were larger in non-cocaine exposed compared to the exposed children (2.3 kg vs.1.6 kg and 2.2 and 1.0 cm).
Children exposed to prenatal cocaine were similar in weight to non-exposed children at 6 years of age. Cocaine had an unexplained greater detrimental effect on non-SGA than SGA children. SGA status at birth has an independent detrimental effect on childhood growth.
Prenatal cocaine exposure; small for gestational age; childhood growth
This study examined the influence of prenatal cocaine exposure on attention and response inhibition measured by continuous performance tests (CPTs) at ages 5 and 7 years.
The baseline sample consisted of 253 cocaine-exposed and 223 non–cocaine-exposed children enrolled prospectively at birth and assessed comprehensively through age 7 years in the longitudinal Miami Prenatal Cocaine Study. This report includes a subsample of 415 children (219 cocaine-exposed, 196 non–cocaine-exposed) who completed at least one CPT assessment at ages 5 and/or 7 years. Prenatal cocaine exposure was measured by maternal self-report and maternal and infant bioassays. Deficits in attention and response inhibition are estimated in relation to prenatal cocaine exposure using generalized estimating equations within the general linear model.
Results indicate cocaine-associated increases in omission errors at ages 5 and 7 as well as increases in response times for target tasks (i.e., slower reaction times) and decreased consistency in performance at age 7. There were no demonstrable cocaine-associated deficits in commission errors. Estimates did not change markedly with statistical adjustment for selected prenatal and postnatal covariates.
Evidence supports cocaine-associated deficits in attention processing through age 7 years.
prenatal cocaine exposure; sustained attention; response inhibition; continuous performance test
The influence of prenatal cocaine exposure on children's language functioning was evaluated longitudinally at six time points from 4 months to 3 years of age. The Miami Prenatal Cocaine Study prospectively enrolled 476 full-term African-American infants at birth, categorized as cocaine-exposed (n = 253) or non-cocaine-exposed (n = 223) by maternal self-report and bioassays (maternal/infant urine, meconium). The Bayley Scales of Infant Development, scored using the Kent Scoring Adaptation for language, was administered at 4, 8, 12, 18, and 24 months. The Clinical Evaluation of Language Fundamentals-Preschool was administered at 3 years. In longitudinal analyses using Generalized Estimating Equations, cocaine-exposed children had lower overall language skills than non-cocaine-exposed children (D = -0.151; 95% CI = -0.269, -0.033; p = .012). Longitudinal findings remained stable after evaluation of potential confounding influences including other prenatal substance exposures and sociodemographic factors. Preliminary evidence also indicated possible mediation through an intermediary effect involving cocaine-associated deficits in fetal growth.
Reports from clinical and experimental (animal) research converge on the suggestion that prenatal exposure to alcohol, cocaine, or marijuana undermines executive functioning (EF) and its neurological underpinnings. However, large, adequately controlled, prospective studies of alcohol and marijuana effects on EF have reported conflicting findings, and there have been no such studies of cocaine exposure.
EF was investigated in a cohort (n = 316) of 4-year-old children the majority of whose mothers had used varying combinations of cocaine, alcohol, and marijuana during pregnancy. With use of postpartum maternal report and biological assay, children were assigned to overlapping prenatal cocaine-exposed, alcohol-exposed, and marijuana-exposed groups and to complementary control groups. The postnatal environmental assessment included measures of maternal intellectual and psychosocial functioning, current drug or alcohol use, and home environment.
The children in the alcohol-exposed group had worse tapping-inhibition performance than children in the non–alcohol-exposed group, and this effect persisted when potential confounding environmental variables, other drug variables, and concurrent verbal intelligence were controlled for.
Prenatal alcohol is predictive of decreased EF in early childhood that could not be attributed to environmental factors. The results are discussed in terms of the age and overall high-risk status of the children.
Alcohol; Inhibition; Frontal; Prenatal; Cocaine
Objectives: This study examined the association between prenatal cocaine exposure and children’s self-regulation at 3 years of child age. In addition to direct effects of prenatal cocaine exposure on children’s self-regulation, we hypothesized there would be indirect associations between cocaine exposure and self-regulation via higher maternal harshness and poor autonomic regulation in infancy. Methods: The sample consisted of 216 mother–infant dyads recruited at delivery from local area hospitals (116 cocaine-exposed, 100 non-exposed). Infant autonomic regulation was measured at 7 months of age during an anger/frustration task, maternal harshness was coded from observations of mother–toddler interactions at 2 years of age, and children’s self-regulation was measured at 3 years of age using several laboratory paradigms. Results: Contrary to hypotheses, there were no direct associations between maternal cocaine use during pregnancy and children’s self-regulation. However, results from testing our conceptual model including the indirect effects via maternal harshness or infant parasympathetic regulation indicated that this model fit the data well, χ2 (23) = 34.36, p > 0.05, Comparative Fit Index = 0.95, RMSEA = 0.05. Cocaine using mothers displayed higher intensity of harshness toward their toddlers during lab interactions across a variety of tasks at 2 years of age (β = 0.23, p < 0.05), and higher intensity of harshness at 2 years was predictive of lower self-regulation at 3 years (β = −0.36, p < 0.01). Maternal cocaine use was also predictive of a non-adaptive increase in respiratory sinus arrhythmia (RSA) from baseline to the negative affect task, but RSA change in infancy was not predictive of self-regulation at 3 years. Conclusion: Results are supportive of animal models indicating higher aggression among cocaine treated dams, and indicate that higher maternal harshness among cocaine using mothers is predictive of child self-regulatory outcomes in the preschool period.
cocaine exposure; self-regulation; maternal harshness; autonomic regulation
Children prenatally exposed to cocaine may be at increased risk for behavioral problems due to disruptions of monaminergically regulated arousal systems and/or environmental conditions.
To assess behavioral outcomes of cocaine (CE) and non-cocaine exposed (NCE) children, 4 through 10 years old, controlling for other prenatal drug exposures and environmental factors.
Low socioeconomic status (SES), primarily African-American children (n = 381 (193 (CE), 188 (NCE)) were recruited from birth. Generalized Estimating Equation (GEE) analyses were used to assess the predictive relationship of prenatal cocaine exposure to odds of caregiver reported clinically elevated behavioral problems at 4, 6, 9 and 10 years of age, controlling for confounders.
Prenatal cocaine exposure was associated with increased rates of caregiver reported delinquency (OR=1.93, CI: 1.09-3.42, p<.02). A significant prenatal cocaine exposure by sex interaction was found for delinquency indicating that only females were affected (OR=3.57, CI: 1.67-7.60, p<.001). There was no effect of cocaine on increased odds of other CBCL subscales. Higher prenatal tobacco exposure was associated with increased odds of externalizing symptoms at 4, 9 and 10 years of age. For CE children, those in foster or adoptive care were rated as having more behavior problems than those in biologic mother or relative care. Greater caregiver psychological distress was associated with increased behavioral problems. There were no independent effects of elevated blood lead level on increased behavior problems after control for prenatal drug exposure and other environmental conditions.
Prenatal cocaine and tobacco exposure were associated with greater externalizing behavior after control for multiple prenatal drug exposures, other environmental and caregiving factors and lead exposure from 4 through 10 years of age. Greater caregiver psychological distress negatively affected caregiver ratings of all CBCL domains. Since cocaine and tobacco use during pregnancy and maternal psychological distress have the potential to be altered through prenatal educational, drug treatment and and mental health interventions, they warrant attention in efforts to reduce rates of problem behaviors in children.
behavior; delinquency; prenatal cocaine-exposure; lead exposure; longitudinal
This study evaluated how enrollment in special education services in 11 year old children relates to prenatal cocaine exposure, psychopathology, and other risk factors.
Participants were 498 children enrolled in The Maternal Lifestyle Study, a prospective, longitudinal, multisite study examining outcomes of children with prenatal cocaine exposure. Logistic regression was used to examine the effect of prenatal cocaine exposure and psychopathology on enrollment in an individualized education plan (a designation specific to children with special education needs), with environmental, maternal, and infant medical variables as covariates.
Prenatal cocaine exposure, an interaction of prenatal cocaine exposure and Oppositional Defiant Disorder, child Attention Deficit Hyperactivity Disorder, parent-reported internalizing behaviors, and teacher-reported externalizing behaviors, predicted enrollment in an individualized education plan. Other statistically significant variables in the model were male gender, low birth weight, being small for gestational age, white race, caregiver change, low socio-economic status, low child intelligence quotient, caregiver depression, and prenatal marijuana exposure.
Prenatal cocaine exposure increased the likelihood of receiving an individualized education plan with adjustment for covariates. Psychopathology also predicted this special education outcome, in combination with and independent of prenatal cocaine exposure.
cocaine; special education; behavior; prenatal substance exposure
Prenatal cocaine exposure has been linked to neurocognitive and developmental outcomes throughout childhood. The cardiovascular toxicity of cocaine is also markedly increased in pregnancy, but it is unknown whether this toxicity affects anthropometric growth and the development of cardiometabolic disease risk factors in the offspring across the lifespan. During the early 1990s, the Miami Prenatal Cocaine Study enrolled a cohort of 476 African American children (253 cocaine-exposed, 223 non-cocaine-exposed) and their biological mothers at delivery in a prospective, longitudinal study. The MPCS has collected 12 prior waves of multidomain data on over 400 infants and their mothers/alternate caregivers through mid-adolescence and is now embarking on an additional wave of data collection at ages 18-19 years. We describe here the analytical methods for examining the relationship between prenatal cocaine exposure, anthropometric growth, and cardiometabolic disease risk factors in late adolescence in this minority, urban cohort. Findings from this investigation should inform both the fields of substance use and cardiovascular research about subsequent risks of cocaine ingestion during pregnancy in offspring.
To examine the impact of prenatal cocaine exposure and maternal behavioral health (recent drug use and psychological functioning) on child behavior at age 5 years.
In this longitudinal investigation, maternal report of child behavior was assessed using the Achenbach Child Behavior Checklist (CBCL) in 140 cocaine-exposed and 181 noncocaine-exposed (61 alcohol, tobacco, and/or marijuana-exposed, and 120 nondrug-exposed) low-income, African American children. Structural equation modeling was used to estimate suspected causal relationships between indicators of maternal behavioral health at 5-year follow-up, according to self-report on a modified Addiction Severity Index (ASI) and CBCL scores.
Prenatal cocaine exposure was not related to child behavior at age 5. Recent maternal drug use and psychological functioning had relationships with CBCL Internalizing and Externalizing scores. However, when considered within a combined model, only maternal psychological functioning remained significant.
Findings highlight the importance of maternal functioning in the behavioral outcome of children exposed prenatally to cocaine.
prenatal cocaine exposure; child behavior; CBCL
The objective of this study was to evaluate the effects of prenatal cocaine exposure on special education at age 7 with adjustment for covariates.
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.
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.
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.
prenatal exposure; cocaine; education; schools
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.
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.
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 β = −.173, 95% CI = −.330, −.016; p = .031), and with adjustment for maternal age and prenatal exposures to alcohol, tobacco, and marijuana (expressive language β = −.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.
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; language functioning; preschool children; CELF-P
To examine the relationship between early parenting stress and later child behavior in a high risk sample and measure the effect of drug exposure on the relationship between parenting stress and child behavior.
A subset of child-caregiver dyads (n = 607) were selected from the Maternal Lifestyle Study, which is a large sample of children (n = 1388) with prenatal cocaine exposure and a comparison sample unexposed to cocaine. Of the 607 dyads, 221 were prenatally exposed to cocaine and 386 were unexposed to cocaine. Selection was based on the presence of a stable caregiver at 4 and 36 months with no evidence of change in caregiver between those time points.
Parenting stress at 4 months significantly predicted child externalizing behavior at 36 months. These relations were unaffected by cocaine exposure suggesting the relationship between parenting stress and behavioral outcome exists for high-risk children regardless of drug exposure history.
These results extend the findings of the relationship between parenting stress and child behavior to a sample of high-risk children with prenatal drug exposure. Implications for outcome and treatment are discussed.
disruptive behavior; parenting stress; high-risk children; prenatal drug exposure; cocaine
Children exposed prenatally to cocaine show deficits in emotion regulation and inhibitory control. While controlling for the measures of medical complication in the perinatal period, environmental risk, and prenatal polydrug exposure (alcohol, tobacco, and marijuana), we examined the effects of prenatal cocaine exposure and gender on attention and inhibitory control in 203 children at ages 6, 9, and 11. Cocaine exposure affected the performance of males, but not females. Heavily exposed males showed deficits in the attention and the inhibition tasks. In addition, a significantly greater proportion of heavily exposed males (21%) than unexposed males (7%) or heavily exposed females (7%) failed to complete the task (p < .01). Even without those poorest performing subjects, the overall accuracy for heavily exposed males (81%) was significantly reduced (p < .05) compared to lightly exposed males (87%) and unexposed males (89%). The findings highlight the importance of considering gender specificity in cocaine exposure effects. Processes by which cocaine effects may be specific to males are discussed.
attention; inhibitory control; prenatal cocaine exposure
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.
Children exposed to cocaine in utero (PCE; n=175) and non-exposed children (NCE; n=175) were followed prospectively to 10 years 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).
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.
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.
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 10 years. Adoptive or foster care appears to enrich PCE children’s linguistic environment and protects children against language delay in the PCE sample.
cocaine; lead; language outcomes; home environment; gender; tobacco; teratology
Two hundred and two primarily African American/Caribbean children (classified by maternal report and infant meconium as 38 heavier, 74 lighter and 89 not cocaine-exposed) were measured repeatedly from birth to age 8 years to assess whether there is an independent effect of prenatal cocaine exposure on physical growth patterns. Children with fetal alcohol syndrome identifiable at birth were excluded. At birth, cocaine and alcohol exposures were significantly and independently associated with lower weight, length and head circumference in cross-sectional multiple regression analyses. The relationship over time of pre-natal exposures to weight, height, and head circumference was then examined by multiple linear regression using mixed linear models including covariates: child’s gestational age, gender, ethnicity, age at assessment, current caregiver, birth mother’s use of alcohol, marijuana and tobacco during the pregnancy and pre-pregnancy weight (for child’s weight) and height (for child’s height and head circumference). The cocaine effects did not persist beyond infancy in piecewise linear mixed models, but a significant and independent negative effect of pre-natal alcohol exposure persisted for weight, height, and head circumference. Catch-up growth in cocaine-exposed infants occurred primarily by 6 months of age for all growth parameters, with some small fluctuations in growth rates in the preschool age range but no detectable differences between heavier versus unexposed nor lighter versus unexposed thereafter.
Cocaine; Alcohol; Pregnancy; Growth; Children
This study examined children’s (n = 140, age 5 years) ability to inhibit a motor response as a function of prenatal cocaine exposure. We hypothesized that cocaine-exposed children would perform worse than unexposed children on the Contrary Tapping task. Results indicated that cocaine exposure, high environmental risk, male gender, and low child IQ each were related to poorer inhibitory control. An interaction indicated that cocaine effects were specific to children who lived in relatively low-risk environments. Cocaine-exposed children made an error sooner than unexposed children if they lived in low-risk environments but not if they lived in high-risk environments. Potential underlying mechanisms and the importance of examining cocaine exposure effects in the context of children’s existing environment are discussed.
cocaine exposure; inhibitory control; impulsivity
Prenatal cocaine exposure has been linked to increased child behavior difficulties in some studies but not others.
The primary aim was to estimate the relationship between in utero cocaine exposure and child behavioral functioning at age 7 years with ratings made by blinded examiners during a structured testing session. A second aim was to examine whether caregiver drug use and psychological problems might mediate suspected relationships between prenatal cocaine exposure and aspects of examiner-rated behavior.
407 children (212 cocaine-exposed, 195 non-exposed) participating in the longitudinal Miami Prenatal Cocaine Study (MPCS) were rated with regard to their behavior during a neuropsychological assessment conducted at age 7 years. Raters were trained research psychometricians blinded to drug exposure. Individual behavioral items were summarized and the cocaine-behavior relationship was estimated within the context of latent variable modeling, using Mplus software.
Two latent variables, Behavioral Regulation and Sociability, were derived via exploratory latent structure analysis with promax rotation. Prenatal cocaine exposure, statistically controlling for child sex, test age, and prenatal exposure to alcohol, tobacco, and marijuana, was associated with Behavioral Regulation (estimated slope ß = -0.25; 95% CI = -0.48, -0.02; p = 0.04) but not Sociability (estimated slope ß = -0.03; 95% CI = -0.26, 0.20; p = 0.79). Neither postnatal drug use by caregivers nor the severity of their psychological problems at age 5 follow-up predicted levels of child Behavioral Regulation or Sociability at age 7 years (p>0.10).
Examiner ratings of child behavior at age 7 revealed less optimal behavioral regulation for prenatally cocaine-exposed compared to non-exposed children, in contrast with what had been previously found from parent-report data. This evidence highlights the potential value of trained observers in assessing behavioral outcomes of children exposed in utero to drugs and other toxicants.
prenatal cocaine exposure; behavior; examiner ratings; caregiver drug use; caregiver psychological functioning; behavioral regulation
This study examined the role of maternal psychopathology and maternal warmth as mediators of the association between prenatal cocaine and other substance exposure and toddler behavior problems. It was also hypothesized that infant cortisol reactivity and environmental risk may moderate these associations. Participants were 220 caregiver–infant dyads (119 cocaine exposed, 101 not cocaine exposed; 49% boys). Mother–infant dyads were recruited at delivery with assessments at 4–8 weeks and 7, 13, and 18 months of child ages. Results yielded no direct associations between prenatal cocaine/other substance exposure and toddler behavior problems, but significant indirect associations between prenatal cigarette/alcohol exposure and toddler behavior problems at 18 months. With regard to moderation, results indicated an indirect association between prenatal cocaine exposure and toddler behavior problems via lower maternal warmth for children with higher, but not lower, cortisol reactivity at 7 months. Results suggest potential pathways to toddler behavior problems among children at high biological risk.
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.
Prenatal cocaine exposure; Language performance
Sleep data were collected by maternal report in a prospective longitudinal follow-up of cocaine exposed and unexposed children. There were 139 subjects: 23 with no prenatal drug exposure, 55 exposed to cocaine alone or in combination with other drugs, and 61 exposed to drugs other than cocaine. Characteristics differed between exposure groups, including birth size, caretaker changes, and maternal SES and postnatal drug use. Compared to those with no drug exposure, children with prenatal drug exposure other than cocaine experienced greater sleep problems (mean [SD], 5 [4.93] vs 7.7 [4.85], p = .026). Prenatal nicotine exposure was a unique predictor of sleep problems (R2 = .028, p = .048). Early sleep problems predicted later sleep problems (all p’s <.01). Together, these preliminary findings suggest possible neurotoxic sleep effects that persist over time. Larger studies, however, need to be conducted that better control for potential postnatal confounding factors.