The association between prenatal cocaine exposure and physiological regulation at 13 months of age

Developmental Pathways from Prenatal Substance Exposure to Reactive Aggression

Few studies have examined etiological pathways from prenatal substance exposure to adolescent reactive aggression. We tested a conceptual model that included hypothesized pathways from prenatal substance exposure to adolescent aggression via autonomic reactivity and violence exposure from infancy to early school age and maternal harshness across early childhood. The sample included 216 families (106 boys) who primarily self-identified as Black or Mixed Race. Results supported the hypothesized path from violence exposure across early childhood and early school age to school age autonomic reactivity and early adolescent reactive aggression. There was also a significant interaction effect of sympathetic and parasympathetic reactivity on adolescent reactive aggression, with sympathetic arousal and parasympathetic suppression at early school age associated with higher reactive relational and physical aggression in adolescence. Results emphasize the importance of early experiences and autonomic nervous system changes in contributing to the cascade of risk for reactive aggression in early adolescence.

Sex moderated and RSA mediated effects of prenatal cocaine exposure on behavior problems at age 7

This study was designed to assess whether prenatal cocaine exposure (PCE) is associated with sex differences in behavior problems in middle childhood and whether there are sex differences in the way in which parasympathetic functioning mediates the relations between PCE and behavior problems within a diverse low-income sample. Participants included 164 high risk mother-child dyads including 89 PC exposed children and 75 control children participating in an ongoing longitudinal study. Respiratory sinus arrhythmia (RSA) was measured to assess parasympathetic functioning at 13 months of age and maternal reports of child behavior problems were collected at 7 years of age. Results revealed no significant association between PCE and behavior problems for the full sample. A 2 × 2 Anova revealed a significant interaction between PCE and child sex on internalizing, externalizing, and total behavior problems (F (3, 160) = 13.45, p < .001) with cocaine exposed females averaging the highest behavior problem scores. Results also revealed a statistically significant indirect effect linking cocaine exposure to lower externalizing problems via lower baseline RSA among males. Findings indicate that cocaine exposed females may be more vulnerable to developing behavior problems than cocaine exposed males and that high baseline RSA may present a sex specific risk factor for externalizing problems among exposed males.

Pathways From Early Family Violence to Adolescent Reactive Aggression and Violence Victimization

PURPOSE

The current study examined how early childhood (EC) family violence and risk (i.e., maternal aggression, sibling aggression, environmental risk) predicted early adolescent (EA) reactive physical and relational aggression and violence victimization through middle childhood (MC) parenting (i.e., guilt induction, power assertive discipline).

METHOD

Mother-infant dyads (N = 216; 72% African American) were recruited as part of a larger longitudinal study on prenatal cocaine and other substance exposure. Observations, interviews, and maternal and child self-report measures were collected from dyads in early childhood (1 to 36 months), middle childhood (84 months), and early adolescence (12 to 15 years).

RESULTS

A cascading path model was specified where current variables were regressed on variables from the preceding time point. Primary results showed that environmental risk and EC child physical aggression predicted higher levels of MC caregiver power assertive discipline, which subsequently predicted lower levels of EA reactive relational aggression. Maternal substance use in pregnancy and the child's continuous placement with biological caregivers predicted higher levels of reactive physical aggression in EA. Finally, MC physical aggression and EA reactive relational aggression predicted higher levels of EA violence victimization.

CONCLUSION

There were a series of direct paths from early childhood family violence and demographic factors to reactive aggression and violence victimization. The current study underscores the importance of evaluating multiple facets of family violence and risk when evaluating aggressive behavior and victimization.

Autonomic functioning among cocaine-exposed kindergarten-aged children: Examination of child sex and caregiving environmental risk as potential moderators

The purpose of this study was to examine the hypothesis that child sex moderates the association between prenatal cocaine exposure (PCE) and autonomic functioning as well as to examine the role that caregiving environmental risk played in sex differences in autonomic functioning among exposed children. Measures of the parasympathetic nervous system (indexed by respiratory sinus arrhythmia [RSA]) and the sympathetic nervous system (indexed by skin conductance level [SCL]) were obtained from 146 (75 cocaine-exposed, 38 male; and 71 nonexposed, 36 male) children during baseline and a task designed to elicit negative affect (NA). We also examined the role of caregiving environmental risk as a moderator of the association between PCE and autonomic functioning separately for boys and girls. PCE boys had a significantly higher baseline RSA and lower baseline SCL than PCE girls or nonexposed children. Environmental risk also moderated the association between PCE and baseline RSA for boys, but not girls, such that boys with PCE and high environmental risk had the highest baseline RSA. These findings indicate that exposed boys had significantly lower levels of sympathetic activation while at rest. However, for autonomic reactivity, the exposed girls had a larger change in both RSA and SCL relative to nonexposed girls while exposed boys had significantly smaller increases in SCL during environmental challenge. Finally, girls with both PCE and high environmental risk had the highest levels of parasympathetic reactivity during challenge. These results underscore the importance of examining sex differences and considering comorbid environmental risk factors when examining developmental outcomes in cocaine-exposed children and highlight the complexity involved with understanding individual differences in cocaine-exposed populations.

The effect of prenatal adversity on externalizing behaviors at 24 months of age in a high-risk sample: Maternal sensitivity as a moderator

The purpose of this study was to examine the moderating role of maternal sensitivity on the association between prenatal adversity and externalizing behaviors at 24 months of age in a diverse, high-risk sample. We hypothesized that among children with higher prenatal adversity, high maternal sensitivity would serve as a protective factor. Participants were 247 primarily low-income, diverse dyads. Results indicated a significant interaction effect of maternal sensitivity and prenatal adversity on externalizing problems. The association between prenatal adversity and externalizing behaviors was significant only among children who experienced low prenatal adversity, with higher maternal sensitivity associated with lower externalizing behaviors. These findings indicate that, in the absence of high prenatal risk, responsive and sensitive parenting can buffer children in an otherwise high-risk sample from the development of externalizing behaviors.

Maternal Pregnancy Diet Quality Is Directly Associated with Autonomic Nervous System Function in 6-Month-Old Offspring

BACKGROUND

Many pregnant women are consuming diets of poor overall quality. Although many studies have linked poor prenatal diet quality to an increased risk of specific diseases in offspring, it is not known if exposure to poor prenatal diet affects core neurophysiological regulatory systems in offspring known to lie upstream of multiple diseases.

OBJECTIVE

We aimed to examine the association between prenatal diet quality and autonomic nervous system (ANS) function in infants at 6 mo of age.

METHODS

Data from 400 women (aged >18 y, with uncomplicated pregnancies) and their infants participating in the Maternal-Infant Research on Environmental Chemicals-Infant Development cohort were used to investigate links between prenatal diet quality and infant ANS function at 6 mo of age. Prenatal diet quality was assessed using the Healthy Eating Index (2010), calculated from a validated FFQ completed by women during the first trimester. Infant ANS function was measured using 2 assessments of heart rate variability (HRV) including root mean square of successive differences (RMSSD) and SD of N-N intervals (SDNN). Associations were analyzed before and after adjustment for socioeconomic status, maternal depression symptoms, maternal cardiometabolic dysfunction, breastfeeding, and prenatal smoking.

RESULTS

Poorer prenatal diet quality was associated with lower infant HRV assessed using RMSSD (B: 0.07; 95% CI: 0.01, 0.13; R2 = 0.013) and SDNN (B: 0.18; 95% CI: 0.02, 0.35; R2 = 0.011). These associations remained significant after adjustment for confounding variables [RMSSD: B: 0.09; 95% CI: 0.003, 0.18; squared semipartial correlation (sp2) = 0.14 and SDNN B: 0.24; 95% CI: 0.0, 0.49; sp2 = 0.13].

CONCLUSIONS

In a large cohort study, poorer prenatal diet quality was associated with lower offspring HRV, a marker of decreased capacity of the ANS to respond adaptively to challenge. Therefore, poor prenatal diet may play a significant role in the programming of multiple organ systems and could increase general susceptibility to disease in offspring.

Prevalence and Perceptions of Electronic Cigarette Use during Pregnancy

Objectives The current study is the first to assess pregnant women's perceptions of e-cigarettes and the prevalence of e-cigarette use during pregnancy, using a national sample of pregnant women (N = 445) recruited online. Methods An online survey was used to assess the prevalence and perceptions of e-cigarette use among pregnant women, including perceptions of e-cigarette safety. Results In our sample, 5.62% (n = 25) of women solely used tobacco cigarettes, 6.52% (n = 29) solely used e-cigarettes, 8.54% (n = 38) used both tobacco cigarettes and e-cigarettes, and 79.33% (n = 353) used neither tobacco cigarettes nor e-cigarettes during their current pregnancy. Overall, 64.27% (n = 286) of participants viewed e-cigarettes as being safer than tobacco cigarettes. Having seen advertisements for e-cigarettes increased likelihood of viewing them as safer than tobacco cigarettes (OR [Odds Ratio] = 2.5, p < .01). Conclusions for Practice Taken together, findings from this study suggest that at least as many women use e-cigarettes during pregnancy as tobacco cigarettes, that pregnant women view e-cigarettes as being safer than tobacco cigarettes, and that these views may be influenced by exposure to e-cigarette advertisements.

Effects of prenatal substance exposure on infant temperament vary by context

This was a prospective longitudinal multisite study of the effects of prenatal cocaine and/or opiate exposure on temperament in 4-month-olds of the Maternal Lifestyle Study (N = 958: 366 cocaine exposed, 37 opiate exposed, 33 exposed to both drugs, 522 matched comparison). The study evaluated positivity and negativity during The Behavior Assessment of Infant Temperament (Garcia Coll et al., 1988). Parents rated temperament (Infant Behavior Questionnaire; Rothbart, 1981). Cocaine-exposed infants showed less positivity overall, mainly during activity and threshold items, more negativity during sociability items, and less negativity during irritability and threshold items. Latent profile analysis indicated individual temperament patterns were best described by three groups: low/moderate overall reactivity, high social negative reactivity, and high nonsocial negative reactivity. Infants with heavy cocaine exposure were more likely in high social negative reactivity profile, were less negative during threshold items, and required longer soothing intervention. Cocaine- and opiate-exposed infants scored lower on Infant Behavior Questionnaire smiling and laughter and duration of orienting scales. Opiate-exposed infants were rated as less respondent to soothing. By including a multitask measure of temperament we were able to show context-specific behavioral dysregulation in prenatally cocaine-exposed infants. The findings indicate flatter temperament may be specific to nonsocial contexts, whereas social interactions may be more distressing for cocaine-exposed infants.

Prenatal substance exposure and child self-regulation: Pathways to risk and protection

A conceptual model of the association between prenatal cocaine exposure (PCE) and child self-regulation via maternal harshness and language development was examined. Specifically, the model tested whether PCE was associated with self-regulation either directly or indirectly via high maternal harshness and poor language development. The role of child sex, autonomic reactivity, and cumulative environmental risk as potential moderators was also explored. The sample was 216 mother-child dyads recruited at birth and assessed at 2, 7, 13, 24, 36, and 48 months of child ages. Participating mothers were primarily African American (72%). Results indicated a significant indirect association between PCE and child effortful control at 36 months via higher maternal harshness. Autonomic reactivity moderated the association between maternal harshness and self-regulation such that among children with poor autonomic reactivity, high maternal harshness was associated with lower conscience at 3 years. Child sex and environmental risk did not moderate the association between PCE and self-regulation. Thus, the quality of caregiving experience played a significant role in the development of self-regulation among PCE children, especially those at higher autonomic risk. In particular, PCE children who also exhibit poor autonomic reactivity may be particularly susceptible to environmental influences such as parenting.

Translational analysis of effects of prenatal cocaine exposure on human infant cries and rat pup ultrasonic vocalizations

Spectral and temporal features of human infant crying may detect neurobehavioral effects of prenatal cocaine exposure (PCE). Finding comparable measures of rodent ultrasonic vocalizations (USVs) would promote translational analyses by controlling the effects of correlated variables that confound human studies. To this end, two studies examined the sensitivity of similar acoustic structures in human infant and rat pup vocalizations to effects of PCE. In Study 1, cry sounds of 107 one month-old infants were spectrum analyzed to create a novel set of measures and to detect the presence of hyperphonation - a qualitative shift to an atypically high fundamental frequency (basic pitch) associated with neurobehavioral insult. Infants with PCE were compared to infants with prenatal polydrug-exposure (PPE) without cocaine and with infants in a standard comparison (SC) group with no prenatal drug exposure. In Study 2, USVs of 118 five day-old rat pups with either PCE, prenatal saline exposure or no prenatal exposures were spectrum analyzed to detect the presence of frequency shifts - acoustic features that have a frequency waveform similar to that of hyperphonation. Results of study 1 showed PCE had two sets of sex-dependent effects on human infants: PCE males had higher pitched cries with more dysphonation (turbulence); PCE females had longer pauses between fewer cry sounds that were of lower amplitude than comparison groups. PCE and PPE infants had more cries with hyperphonation than SC infants. In study 2, PCE pups had a greater percentage of USVs with shift in the acoustic structure than pups in the two control groups. As such, the novel measures of human infant crying and rat pup USVs were sensitive to effects of PCE. These studies provide the first known translational analysis of similar acoustic structures of vocalizations in two species to detect adverse effects of prenatal drug exposure.

Empathic responsivity at 3 years of age in a sample of cocaine-exposed children

This study examined the association between prenatal exposure to cocaine and behavioral and physiological responsivity. Participants were 216 mother-infant dyads (116 cocaine exposed-CE, 100 nonexposed-NCE) recruited at birth. Measures of heart rate (HR) and respiratory sinus arrhythmia (RSA) were obtained during baseline and during a task designed to elicit empathy (exposure to infant crying). When the effects of prenatal cocaine use were examined in the context of polydrug use, results of model testing indicated that lower gestational age, prenatal exposure to cocaine and postnatal exposure to alcohol were each associated with a reduced suppression of RSA during the empathy task. These findings provide additional support for an association between prenatal cocaine exposure and dysregulation during early childhood during affect-eliciting environmental challenges.

Behavior problems among cocaine exposed children: role of physiological regulation and parenting

This study examined interrelations between prenatal cocaine exposure, child autonomic regulation, parenting behavior and child sex on parent-reported behavior problems at 36 months of age. We hypothesized that respiratory sinus arrhythmia (RSA) at 13 months of age would mediate the relation between cocaine exposure and behavior problems. We also hypothesized that child sex, maternal negative affect, and maternal sensitivity observed at 13 months of age would moderate the relation between RSA and behavior problems. Results revealed that cocaine exposure predicted low baseline RSA and low RSA withdrawal during a negative affect task. Low baseline RSA, in turn, predicted fewer behavior problems offering support for an indirect association between cocaine exposure and behavior problems. The association between baseline RSA and behavior problems was further moderated by maternal negative affect such that high baseline RSA was more strongly related to behavior problems under conditions of high compared to low maternal negative affect. Results also revealed a near significant trend for baseline RSA to be more strongly related to behavior problems among boys than girls. These findings highlight several possible pathways toward behavior problems among cocaine exposed children.

Profiles of Reactivity in Cocaine-Exposed Children

This study explored the possibility that specific, theoretically consistent profiles of reactivity could be identified in a sample of cocaine-exposed infants and whether these profiles were associated with a range of infant and/or maternal characteristics. Cluster analysis was used to identify distinct groups of infants based on physiological, behavioral and maternal reported measures of reactivity. Five replicable clusters were identified which corresponded to 1) Dysregulated/High Maternal Report Reactors, 2) Low Behavioral Reactors, 3) High Reactors, 4) Optimal Reactors and 5) Dysregulated/Low Maternal Report Reactors. These clusters were associated with differences in prenatal cocaine exposure status, birthweight, maternal depressive symptoms, and maternal negative affect during mother-infant interactions. These results support the presence of distinct reactivity profiles among high risk infants recruited on the basis of prenatal cocaine exposure and demographically similar control group infants not exposed to cocaine.

Cocaine Exposure and Children's Self-Regulation: Indirect Association via Maternal Harshness

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, χ(2) (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.

Maternal cocaine use and mother-toddler aggression

This study examined the direct and indirect associations between maternal cocaine use during pregnancy and mother-toddler aggression in an interactive context at 2 years of child age. We hypothesized that in addition to direct effects of cocaine exposure on maternal and child aggression, the association between maternal cocaine use and mother-toddler aggression may be indirect via higher maternal psychiatric symptoms, negative affect, or poor infant autonomic regulation at 13 months. Participants consisted of 220 (119 cocaine exposed, 101 non-cocaine exposed) mother-toddler dyads participating in an ongoing longitudinal study of prenatal cocaine exposure. Results indicated that mothers who used cocaine during pregnancy displayed higher levels of aggression toward their toddlers compared to mothers in the control group. Results from model testing indicated significant indirect associations between maternal cocaine use and maternal aggression via higher maternal negative affect as well as lower infant autonomic regulation at 13 months. Although there were no direct associations between cocaine exposure and toddler aggression, there was a significant indirect effect via lower infant autonomic regulation at 13 months. Results highlight the importance of including maternal aggression in predictive models of prenatal cocaine exposure examining child aggression. Results also emphasize the important role of infant regulation as a mechanism partially explaining associations between cocaine exposure and mother-toddler aggression.

Some reflections on the use of psychiatric diagnosis in the looked after or "in care" child population

The current classification system, DSM-IV, inadequately captures the range and type of psychopathology seen in the "in care" population of children. A combination of pre-natal influences, early interpersonal trauma involving the primary caregiving relationship, disturbed and disrupted attachment relationships and other significant losses and adverse environmental effects produce a complex constellation of symptoms and a pervasive impact on development that is difficult to categorize. The challenges facing DSM-V are illustrated, highlighting unresolved topics such as quasi-autism, reactive attachment disorder and complex trauma.