Life satisfaction for adolescents with developmental and behavioral disabilities during the COVID-19 pandemic.

BACKGROUND: This study aimed to identify contextual factors associated with life satisfaction during the COVID-19 pandemic for adolescents with mental, emotional, behavioral, and developmental (MEBD) disabilities. METHODS: Data were collected from a sample of 1084 adolescents aged 11-21 years from April 2020 to August 2021. This cross-sectional study used a sequential machine learning workflow, consisting of random forest regression and evolutionary tree regression, to identify subgroups of adolescents in the Environmental influences on Child Health Outcomes (ECHO) consortium who demonstrated enhanced vulnerability to lower life satisfaction as described by intersecting risk factors, protective factors, and MEBD disabilities. RESULTS: Adolescents with a history of depression, anxiety, autism, and attention-deficit/hyperactivity disorder were particularly susceptible to decreased life satisfaction in response to unique combinations of stressors experienced during the COVID-19 pandemic. These stressors included decreased social connectedness, decreased family engagement, stress related to medical care access, pandemic-related traumatic stress, and single-caregiver households. CONCLUSION: Findings from this study highlight the importance of interventions aimed specifically at increasing adolescent social connectedness, family engagement, and access to medical support for adolescents with MEBD disabilities, particularly in the face of stressors, such as a global pandemic. IMPACT: Through a machine learning process, we identified contextualized risks associated with life satisfaction among adolescents with neurodevelopmental disabilities during the COVID-19 pandemic. The COVID-19 pandemic resulted in large-scale social disruptions for children and families. Such disruptions were associated with worse mental health outcomes in the general pediatric population, but few studies have examined specific subgroups who may be at heightened risk. We endeavored to close that gap in knowledge. This study highlights the importance of social connectedness, family engagement, and access to medical support as contributing factors to life satisfaction during the COVID-19 pandemic for adolescents with neurodevelopmental disabilities.

Trajectories of maternal depressive symptoms from infancy through early childhood: The roles of perceived financial strain, social support, and intimate partner violence.

Although new mothers are at risk of heightened vulnerability for depressive symptoms, there is limited understanding regarding changes in maternal depressive symptoms over the course of the postpartum and early childhood of their child's life among rural, low-income mothers from diverse racial backgrounds. This study examined distinct trajectories of depressive symptoms among rural low-income mothers during the first five years of their child's life, at 6, 15, 24, and 58 months, using data from the Family Life Project (N = 1,292). Latent class growth analysis identified four distinct trajectories of maternal depressive symptoms, including Low-decreasing (50%; n = 622), Low-increasing (26%; n = 324), Moderate-decreasing (13%; n = 156), and Moderate-increasing (11%; n = 131) trajectories. Multinomial logistic regression demonstrated that higher perceived financial strain and intimate partner violence, and lower social support predicted higher-risk trajectories (Low-increasing, Moderate-decreasing, and Moderate-increasing) relative to the Low-decreasing trajectory. Compared to the Low-decreasing trajectory, lower neighborhood safety/quietness predicted to the Low-increasing trajectory. Moreover, lower social support predicted the Moderate-increasing trajectory, the highest-risk trajectory, compared to those in Moderate-decreasing. The current analyses underscore the heterogeneity on patterns of depressive symptoms among rural, low-income mothers, and that the role of both proximal and broader contexts contributing to distinct trajectories of maternal depressive symptoms over early childhood.

Increased risk of attention-deficit/hyperactivity disorder in adolescents with high salivary levels of copper, manganese, and zinc.

Exposure to toxic heavy metals has been associated with the development of attention-deficit/hyperactivity disorder (ADHD). However, fewer studies have examined the associations between abnormal levels of essential trace metals and ADHD, and none have done so using saliva. We investigated whether salivary metals were associated with ADHD in adolescents aged 12 from the Family Life Project (FLP) using a nested case-control study design that included 110 adolescents who met diagnostic criteria for inattentive (ADHD-I), hyperactive-impulsive (ADHD-H), or combined type ADHD (ADHD-C) (cases) and 173 children who did not (controls). We used inductively coupled plasma optical emission spectrophotometry to measure chromium, copper, manganese, and zinc in saliva samples. We employed logistic regression models to examine associations between quartile levels of individual metals and ADHD outcomes by subtype. Salivary copper levels were significantly associated with increased odds of any ADHD diagnosis (OR = 3.31, 95% CI: 1.08-10.12; p = 0.04) and with increased odds of ADHD-C diagnosis (OR = 8.44, 95% CI: 1.58-45.12; p = 0.01). Salivary zinc levels were significantly associated with increased odds of ADHD-C diagnosis (OR = 4.06, 95% CI: 1.21-13.69; p = 0.02). Salivary manganese levels were also significantly associated with increased odds of ADHD-C diagnosis (OR = 5.43, 95% CI: 1.08-27.27, p = 0.04). This is the first study using saliva to assess metal exposure and provide a potential link between salivary levels of copper, manganese, and zinc and ADHD diagnoses in adolescents. Public health interventions focused on metal exposures might reduce ADHD incidence in low-income, minority communities.

Sensitive caregiving and reward responsivity: A novel mechanism linking parenting and executive functions development in early childhood.

Sensitive caregiving is an essential aspect of positive parenting that influences executive functions development, but the mechanisms underlying this association are less clear. Using data from the Family Life Project, a large prospective longitudinal sample of 1292 families residing in rural, predominately low-income communities, the current study examined whether sensitive caregiving impacts executive functions development by shaping behavioral reward processing systems in early postnatal life. Results indicated that higher levels of sensitive caregiving during infancy were associated with heightened reward responsivity at age 4, which in turn predicted superior executive functions ability at age 5. Notably, children's reward responsivity partially mediated the relationship between sensitive caregiving in infancy and executive functions ability at school entry. These findings add to prior work on early experience and children's executive functions and highlight caregiver scaffolding of developing reward processing systems as a potential foundational mechanism for supporting adaptive behavior and self-regulation across the lifespan.

Profiles of early family environments and the growth of executive function: Maternal sensitivity as a protective factor.

We identified family risk profiles at 6 months using socioeconomic status (SES) and maternal mental health indicators with data from the Family Life Project (N = 1,292). We related profiles to executive function (EF) at 36 months (intercept) and growth in EF between 36 and 60 months. Latent profile analysis revealed five distinct profiles, characterized by different combinations of SES and maternal mental health symptoms. Maternal sensitivity predicted faster growth in EF among children in the profile characterized by deep poverty and the absence of maternal mental health symptoms. Maternal sensitivity also predicted higher EF intercept but slower EF growth among children in the profile characterized by deep poverty and maternal mental health symptoms, and children in the near poor (low SES), mentally healthy profile. Maternal sensitivity also predicted higher EF intercept but had no effect on growth in EF in the near poor, mentally distressed profile. In contrast, maternal sensitivity did not predict the intercept or growth of EF in the privileged SES/mentally healthy profile. Our findings using a person-centered approach provide a more nuanced understanding of the role of maternal sensitivity in the growth of EF, such that maternal sensitivity may differentially affect the growth of EF in various contexts.

Why do humans undergo an adiposity rebound? Exploring links with the energetic costs of brain development in childhood using MRI-based 4D measures of total cerebral blood flow.

BACKGROUND: Individuals typically show a childhood nadir in adiposity termed the adiposity rebound (AR). The AR serves as an early predictor of obesity risk, with early rebounders often at increased risk; however, it is unclear why this phenomenon occurs, which could impede understandings of weight gain trajectories. The brain's energy requirements account for a lifetime peak of 66% of the body's resting metabolic expenditure during childhood, around the age of the AR, and relates inversely to weight gain, pointing to a potential energy trade-off between brain development and adiposity. However, no study has compared developmental trajectories of brain metabolism and adiposity in the same individuals, which would allow a preliminary test of a brain-AR link. METHODS: We used cubic splines and generalized additive models to compare age trajectories of previously collected MRI-based 4D flow measures of total cerebral blood flow (TCBF), a proxy for cerebral energy use, to the body mass index (BMI) in a cross-sectional sample of 82 healthy individuals (0-60 years). We restricted our AR analysis to pre-pubertal individuals (0-12 years, n = 42), predicting that peak TCBF would occur slightly after the BMI nadir, consistent with evidence that lowest BMI typically precedes the nadir in adiposity. RESULTS: TCBF and the BMI showed inverse trajectories throughout childhood, while the estimated age at peak TCBF (5.6 years) was close but slightly later than the estimated age of the BMI nadir (4.9 years). CONCLUSIONS: The timing of peak TCBF in this sample points to a likely concordance between peak brain energetics and the nadir in adiposity. Inverse age trajectories between TCBF and BMI support the hypothesis that brain metabolism is a potentially important influence on early life adiposity. These findings also suggest that experiences influencing the pattern of childhood brain energy use could be important predictors of body composition trajectories.

Mothers' and fathers' executive function both predict emergent executive function in toddlerhood.

There are multivariate influences on the development of children's executive function throughout the lifespan and substantial individual differences can be seen as early as when children are 1 and 2 years of age. These individual differences are moderately stable throughout early childhood, but more research is needed to better understand their origins. To some degree, individual differences in executive function are correlated between mother and child, but no research to date has examined these associations prior to when children are preschool age, nor have any studies considered the role of fathers' and mothers' executive function in tandem. Here, we use a sample of 484 families (Mothers 89.2% white; Fathers 92.5% white) in three countries (UK, USA, Netherlands) to investigate the role of each parents' executive function on the development of children's (49.7% female) executive function from 14 (M = 14.42, SD = 0.57) to 24 (M = 24.47, SD = 0.78) months, as well as parenting practices that underlie these associations. Results of structural equation models suggest stability in some-but not all-components of executive function and growing unity between components as children age. We replicate extant findings such that mothers' executive function predicts children's executive function over and above stability and extend these findings to include associations between father and child skills. We find an additive role of fathers' EF, similar in magnitude to the role of mothers' EF. Finally, for both mothers and fathers we find that sensitivity and autonomy supportive practices mediate the relations between parents' and children's executive function.

Within-person changes in basal cortisol and caregiving modulate executive attention across infancy.

One pathway by which environments of socioeconomic risk are thought to affect cognitive development is through stress physiology. The biological systems underpinning stress and attention undergo a sensitive period of development during infancy. Psychobiological theory emphasizes a dynamic pattern of context-dependent development, however, research has yet to examine how basal cortisol and attention dynamically covary across infancy in ecologically valid contexts. Thus, to address these gaps, we leveraged longitudinal, multilevel analytic methods to disentangle between- from within-person associations of hypothalamic-pituitary-adrenal (HPA) axis activity and executive attention behaviors across infancy. We use data from a large longitudinal sample (N = 1,292) of infants in predominantly low-income, nonurban communities at 7-, 15-, and 24-months of age. Using multilevel models, we investigated longitudinal associations of infant attention and basal cortisol levels and examined caregiving behaviors as moderators of this relationship. Results indicated a negative between- and within-person association between attention and cortisol across infancy and a within-person moderation by caregiver responsiveness. In other words, on the within-person level, higher levels of cortisol were concomitantly associated with lower infant attention across the first 2 years of life. However, variation in the caregiver's level of responsiveness either buffered or sensitized the executive attention system to the negative effects of physiological stress.

A hypothesis linking the energy demand of the brain to obesity risk.

The causes of obesity are complex and multifactorial. We propose that one unconsidered but likely important factor is the energetic demand of brain development, which could constrain energy available for body growth and other functions, including fat deposition. Humans are leanest during early childhood and regain body fat in later childhood. Children reaching this adiposity rebound (AR) early are at risk for adult obesity. In aggregate data, the developing brain consumes a lifetime peak of 66% of resting energy expenditure in the years preceding the AR, and brain energy use is inversely related to body weight gain from infancy until puberty. Building on this finding, we hypothesize that individual variation in childhood brain energy expenditure will help explain variation in the timing of the AR and subsequent obesity risk. The idea that brain energetics constrain fat deposition is consistent with evidence that genes that elevate BMI are expressed in the brain and mediate a trade-off between the size of brain structures and BMI. Variability in energy expended on brain development and function could also help explain widely documented inverse relationships between the BMI and cognitive abilities. We estimate that variability in brain energetics could explain the weight differential separating children at the 50th and 70th BMI-for-age centiles immediately before the AR. Our model proposes a role for brain energetics as a driver of variation within a population's BMI distribution and suggests that educational interventions that boost global brain energy use during childhood could help reduce the burden of obesity.

Capturing Environmental Dimensions of Adversity and Resources in the Context of Poverty Across Infancy Through Early Adolescence: A Moderated Nonlinear Factor Model.

Income, education, and cumulative-risk indices likely obscure meaningful heterogeneity in the mechanisms through which poverty impacts child outcomes. This study draws from contemporary theory to specify multiple dimensions of poverty-related adversity and resources, with the aim of better capturing these nuances. Using data from the Family Life Project (N = 1,292), we leveraged moderated nonlinear factor analysis (Bauer, 2017) to establish group- and longitudinally invariant environmental measures from infancy to early adolescence. Results indicated three latent factors-material deprivation, psychosocial threat, and sociocognitive resources-were distinct from each other and from family income. Each was largely invariant across site, racial group, and development and showed convergent and discriminant relations with age-twelve criterion measures. Implications for ensuring socioculturally valid measurements of poverty are discussed.

Examining the Effects of Changes in Classroom Quality on Within-Child Changes in Achievement and Behavioral Outcomes.

This study examines whether changes in classroom quality predict within-child changes in achievement and behavioral problems in elementary school (ages spanning approximately 6-11 years old). Drawing on data from a longitudinal study of children in predominantly low-income, nonurban communities (n = 1,078), we relied on child fixed effects modeling, which controlled for stable factors that could bias the effects of classroom quality. In general, we found that changes in classroom quality had small and statistically nonsignificant effects on achievement and behavior. However, we found that moving into a high-quality classroom, particularly those rated as high in Classroom Organization, had positive effects on achievement and behavior for children with significant exposure to poverty in early life.

Prenatal mother-father cortisol linkage predicts infant executive functions at 24 months.

The present study investigated associations between prenatal mother-father cortisol linkage and infant executive functions. Data come from an international sample (N = 358) of predominantly white and middle- to upper-class first-time parents. During late pregnancy, parents collected diurnal salivary cortisol samples and reported on levels of psychological stress. At 24 months, children completed a battery of executive function tasks. Parent cortisol linkage was operationalized as the time-dependent, within-dyad association between maternal and paternal diurnal cortisol. Results indicated that prenatal linkage was positively related to infant executive functions, suggesting that stronger mother-father cortisol linkage was associated with higher executive function scores. Additionally, this relation was moderated by paternal average cortisol levels such that executive function scores were lower when fathers had higher average cortisol levels and linkage was weak. This association suggests that elevated paternal cortisol amplifies the negative relation between lower cortisol linkage and lower infant executive function scores. Importantly, these findings were observed while controlling for observational measures of caregiving and self-report measures of psychosocial functioning and infant social-emotional behavior. These results suggest that prenatal linkage of mother's and father's stress physiology plays a potentially important part in programming and regulating infant neurocognitive development.

Association between environmental tobacco smoke exposure across the first four years of life and manifestation of externalizing behavior problems in school-aged children.

BACKGROUND: Extensive literature in human and animal models has documented an association between maternal smoking during pregnancy and externalizing behavior in offspring. It remains unclear; however, the extent to which postnatal environmental smoke exposure is associated with behavioral development, particularly for children whose mothers did not smoke during pregnancy. The present study examined whether magnitude of exposure to environmental smoke across the first four years of life demonstrated a linear association with later externalizing symptoms. METHODS: Exposure was quantified through salivary cotinine measured when children were 6, 15, 24, and 48 months of age, providing a more accurate quantification of realized exposure than can be estimated from parental report of cigarettes smoked. Data were available for n = 1,096 (50% male; 44% African American) children recruited for the Family Life Project, a study of child development in areas of rural poverty. RESULTS: Analyses indicate a linear association between cotinine and children's symptoms of hyperactivity and conduct problems. This association remained significant after controlling for family poverty level, parental education, parental history of ADHD, hostility, depression, caregiver IQ, and obstetric complications. Furthermore, this association was unchanged when excluding mothers who smoked during pregnancy from the model. CONCLUSIONS: Findings are consistent with animal models demonstrating an effect of environmental exposure to nicotine on ongoing brain development in regions related to hyperactivity and impulsivity, and highlight the importance of mitigating children's exposure to environmental smoke, including sources that extend beyond the parents.

Understanding the terrible twos: A longitudinal investigation of the impact of early executive function and parent-child interactions.

Impairments in both executive function and parent-child interactions are associated with child externalizing behavior, but few studies have tested the uniqueness of these associations in the first years of life. Addressing these gaps, the current study involved an international sample (N = 438; 218 boys) who, at 14 and 24 months, completed an innovative battery of executive function tasks and were filmed at home in dyadic interaction with their mothers, enabling detailed observational ratings of maternal support. In addition, parents rated infant temperament at 4 months and externalizing behavior at 14 and 24 months. Cross-lagged longitudinal analysis showed a unidirectional developmental association between executive function at 14 months and externalizing behavior at 24 months. In addition, infant negative affect moderated the inverse association between maternal support at 14 months and externalizing behavior at 24 months. The benefits of maternal support were only evident for children with low levels of negative affect in infancy. We discuss this finding in relation to theoretical models that highlight child effects (e.g. models of vantage sensitivity).

The development of executive function in early childhood is inversely related to change in body mass index: Evidence for an energetic tradeoff?

A well-established literature demonstrates executive function (EF) deficits in obese children and adults relative to healthy weight comparisons. EF deficits in obesity are associated with overeating and impulsive consumption of high calorie foods leading to excess weight gain and to problems with metabolic regulation and low-grade inflammation that detrimentally affect the structure and function of prefrontal cortex. Here, we test a complementary explanation for the relation between EF and body mass index (BMI) grounded in the energy demand of the developing brain. Recent work shows that the brain accounts for a lifetime peak of 66% of resting metabolic rate in childhood and that developmental changes in brain energetics and normative changes in body weight gain are closely inversely related. This finding suggests a trade-off in early childhood between energy used to support brain development versus energy used to support physical growth and fat deposition. To test this theorized energetic trade-off, we analyzed data from a large longitudinal sample (N = 1,292) and found that change in EF from age 3 to 5 years, as a proxy for brain development in energetically costly prefrontal cortex, is inversely related to change in BMI from age 2 to 5 years. Greater linear decline in BMI predicted greater linear increase in EF. We interpret this finding as tentative support for a brain-body energetic trade-off in early childhood with implications for lifetime obesity risk.

Parental well-being, couple relationship quality, and children's behavioral problems in the first 2 years of life.

Adverse effects of early exposure to parental mood disturbance on child adjustment have been documented for both mothers and fathers, but are rarely examined in tandem. Other under-researched questions include effects of changes over time in parental well-being, similarities and contrasts between effects of parental mood disturbance on children's internalizing versus externalizing problems, and potential mediating effects of couple relationship quality. The current study involved 438 couples who reported symptoms of depression and anxiety at each of four time points (i.e., last trimester of pregnancy and 4, 14, and 24 months postbirth). Mothers and fathers also rated their couple relationship quality and their child's socioemotional adjustment at 14 months, as well as internalizing and externalizing problems at 24 months. Latent growth models indicated direct effects of (a) maternal prenatal well-being on externalizing problems at 24 months, and (b) paternal prenatal well-being on socioemotional problems at 14 months. Internalizing symptoms at 24 months showed only indirect associations with parental well-being, with couple relationship quality playing a mediating role. Our findings highlight the importance of prenatal exposure to parental mood disturbance and demonstrate that, even in a low-risk sample, poor couple relationship quality explains the intergenerational stability of internalizing problems.

Early life predictors of attention deficit/hyperactivity disorder symptomatology profiles from early through middle childhood.

This study used repeated measures data to identify developmental profiles of elevated risk for ADHD (i.e., six or more inattentive and/or hyperactive-impulsive symptoms), with an interest in the age at which ADHD risk first emerged. Risk factors that were measured across the first 3 years of life were used to predict profile membership. Participants included 1,173 children who were drawn from the Family Life Project, an ongoing longitudinal study of children's development in low-income, nonmetropolitan communities. Four heuristic profiles of ADHD risk were identified. Approximately two thirds of children never exhibited elevated risk for ADHD. The remaining children were characterized by early childhood onset and persistent risk (5%), early childhood limited risk (10%), and middle childhood onset risk (19%). Pregnancy and delivery complications and harsh-intrusive caregiving behaviors operated as general risk for all ADHD profiles. Parental history of ADHD was uniquely predictive of early onset and persistent ADHD risk, and low primary caregiver education was uniquely predictive of early childhood limited ADHD risk. Results are discussed with respect to how changes to the age of onset criterion for ADHD in DSM5 may affect etiological research and the need for developmental models of ADHD that inform ADHD symptom persistence and desistance.

Elevated infant cortisol is necessary but not sufficient for transmission of environmental risk to infant social development: Cross-species evidence of mother-infant physiological social transmission.

Environmental adversity increases child susceptibility to disrupted developmental outcomes, but the mechanisms by which adversity can shape development remain unclear. A translational cross-species approach was used to examine stress-mediated pathways by which poverty-related adversity can influence infant social development. Findings from a longitudinal sample of low-income mother-infant dyads indicated that infant cortisol (CORT) on its own did not mediate relations between early-life scarcity-adversity exposure and later infant behavior in a mother-child interaction task. However, maternal CORT through infant CORT served as a mediating pathway, even when controlling for parenting behavior. Findings using a rodent "scarcity-adversity" model indicated that pharmacologically blocking pup corticosterone (CORT, rodent equivalent to cortisol) in the presence of a stressed mother causally prevented social transmission of scarcity-adversity effects on pup social behavior. Furthermore, pharmacologically increasing pup CORT without the mother present was not sufficient to disrupt pup social behavior. Integration of our cross-species results suggests that elevated infant CORT may be necessary, but without elevated caregiver CORT, may not be sufficient in mediating the effects of environmental adversity on development. These findings underscore the importance of considering infant stress physiology in relation to the broader social context, including caregiver stress physiology, in research and interventional efforts.

Magnitude and Chronicity of Environmental Smoke Exposure Across Infancy and Early Childhood in a Sample of Low-Income Children.

INTRODUCTION: Infants and young children may be at an increased risk for second- and thirdhand exposure to tobacco smoke because of increased respiration rate and exposure to surface residue. However, relatively fewer studies have examined biomarkers of exposure (cotinine) in children under age 4 years. This study examines the magnitude and chronicity of exposure across early childhood among children from low-income families in order to better characterize contextual risk factors associated with exposure. METHODS: A total of 1292 families were recruited in six nonurban counties of Pennsylvania and North Carolina. Cotinine was assayed from infant saliva at 6, 15, 24, and 48 months of age (N = 1218), and categorized as low (≤0.45 ng/mL), moderate (0.46-12 ng/mL), or high (≥12 ng/mL) at each time point. Categories were highly correlated across time. Latent class analysis was used to summarize patterns of exposure categories across time. RESULTS: Magnitude of exposure in this sample was high, with approximately 12% of infants registering cotinine values at least 12 ng/mL, consistent with active smoking in adults. Greater exposure was associated with lower income, less education, more residential instability, and more instability in adult occupants in the home, whereas time spent in center-based day care was associated with lower exposure. CONCLUSIONS: Young children from low-income, nonurban communities appear to bear a higher burden of secondhand smoke exposure than previous studies have reported. Results contribute to understanding populations at greater risk, as well as specific, potentially malleable, environmental factors that may be examined as direct contributors to exposure. IMPLICATIONS: Results suggest that infants from low-income, nonurban families have higher risk for environmental smoke exposure than data from nationally representative samples. Predictors of exposure offer insights into specific factors that may be targeted for risk reduction efforts, specifically conditions of children's physical space. In addition to considering the increases in risk when an adult smoker lives in a child's home, families should also attend to the possible risk embedded within the home itself, such as residual smoke from previous occupants. For high-risk children, day care appears to mitigate the magnitude of exposure by providing extended time in a smoke-free environment.

Maternal Language and Child Vocabulary Mediate Relations Between Socioeconomic Status and Executive Function During Early Childhood.

This article examined longitudinal relations among socioeconomic risk, maternal language input, child vocabulary, and child executive function (EF) in a large sample (N = 1,009) recruited for a prospective longitudinal study. Two measures of maternal language input derived from a parent-child picture book task, vocabulary diversity (VOCD), and language complexity, showed variation by socioeconomic risk at child ages 15, 24, and 36 months. Maternal VOCD at child age 24 months and maternal language complexity at child age 36 months mediated the relation between socioeconomic risk and 48-month child EF, independent of parenting sensitivity. Moreover, 36-month child vocabulary mediated the relation between maternal language input and child EF. These findings provide novel evidence about mechanisms linking socioeconomic risk and child executive function.