Associations between Adolescent Alcohol Use and Neurocognitive Functioning in Young Adulthood.

This study examined the associations between excessive alcohol intake during adolescence and neurocognitive functioning in young adulthood and whether these relations varied by sex. Participants were working-class Chilean adolescents (N = 692; Mage 16.0 years; 54.5% female) who provided frequency of past 30-day bingeing and past-year intoxication. Neurocognitive measures were completed in young adulthood (Mage 21.2 years). Illicit substance users were excluded a priori and other substance use was controlled. When males and females were considered simultaneously, no main effects of intoxication or bingeing were found. However, several sex-specific effects emerged for intoxication, such that more frequent intoxication was associated with poorer visual memory, attention, processing speed, response inhibition, and cognitive flexibility in females, while frequent intoxication related to better attention and processing speed in males. In general, effect sizes were small. No relations emerged for verbal memory, working memory, or spatial learning. Possible factors that contribute to divergent sex effects are discussed.

Socioeconomic position and executive functioning from childhood to young adulthood: Evidence from Santiago, Chile.

BACKGROUND: Optimizing cognitive development through early adulthood has implications for population health. This study aims to understand how socioeconomic position (SEP) across development relates to executive functioning. We evaluate three frameworks in life-course epidemiology - the sensitive period, accumulation, and social mobility hypotheses. METHODS: Participants were young adults from Santiago, Chile who were studied from 6 months to 21 years. Family SEP was measured at ages 1 y, 10 y, and 16 y with the modified Graffar Index. Executive functioning was assessed at ages 16 y and 21 y by the Trail Making Test Part B (Trails B). Analyses estimating 16 y and 21 y executive function involved 581 and 469 participants, respectively. Trails B scores were modeled as a function of SEP at 1 y, 10 y, and 16 y, as the total accumulation of disadvantage, and as change in SEP between 1 y and 10 y and between 10 y and 16 y. RESULTS: Participants were low- to middle-income in infancy and, on average, experienced upwards mobility across childhood. Half of participants (58%) improved Trails B scores from 16 y and 21 y. Most (68%) experienced upward social mobility between infancy and 16 y. When examined independently, worse SEP measured at 10 y and 16 y related to worse (longer time to complete) Trails B scores at Age 21 but did not relate to the other outcomes. After mutual adjustment as a test of the sensitivity hypothesis, no SEP measure was independently related to any outcome. Testing the accumulation hypothesis, cumulative low SEP was associated with worse cognitive performance at 21 y (ß = 3.6, p = 0.04). Results for the social mobility hypothesis showed no relation to cognitive scores or to change in cognitive scores. Comparing all hypotheses, SEP at 16 y explained the most variability in executive functioning at 21 y, providing support for the sensitive period hypothesis. CONCLUSIONS: Results indicate that experiencing cumulatively low socioeconomic position from infancy to adolescence can have a negative impact on cognitive functioning in young adulthood. Findings also provide evidence in support of adolescence as a key developmental period during which SEP can most strongly impact cognitive functioning.

Breastfeeding Duration and Timing of Bottle Supplementation: Associations with Body Mass Index from Childhood to Young-Adulthood.

Evidence for the association between breastfeeding (BF) duration and later body mass index (BMI) is inconsistent. We explored how BF duration and BF type (exclusive or partial) related to BMI from childhood to young adulthood in a Chilean cohort. Infants were recruited at 6 months between 1994 and 1996 in Santiago, Chile (n = 821). Mothers reported date of first bottle and last BF; anthropometry was measured at 1, 5, 10, 16, and 23 years. We tested whether: (1) type of BF at 6 months (none, partial, exclusive) and (2) duration of exclusive BF (<1 month, 1 to <3 months, 3 to <6 months, and ≥6 months) related to BMI. At 6 months, 35% received both breastmilk and formula ("partial BF") and 38% were exclusively breastfed. We found some evidence of an association between longer BF and lower BMI z-scores at young ages but observed null effects for later BMI. Specifically, BF for 3 to <6 months compared to <1 month related to lower BMI z-scores at 1 and 5 years (both p < 0.05). Our results are in partial accordance with others who have not found a protective effect of longer BF for lower BMI.

Adolescent sedentary behavior and body composition in early adulthood: results from a cohort study.

BACKGROUND: This study investigates the cross-sectional and prospective associations between accelerometer-measured sedentary behavior and body composition from adolescence to early adulthood. METHODS: Data from the Santiago Longitudinal Study were analyzed (n = 212). Sedentary time was measured at age 16 years, and body composition (body mass index [BMI], waist circumference, waist-to-height ratio [WHtR], fat mass percentage, and lean mass percentage) was examined at both age 16 and 23 years. Adjusted linear regression models estimated associations between sedentary time, sedentary bout duration, and body composition, overall and by sex. RESULTS: In all analyses, mean sedentary bout duration was not associated with body composition. In cross-sectional analyses, more sedentary time during adolescence was significantly associated with lower BMI, waist circumference, WHtR, fat mass percentage, and higher lean mass percentage (p < 0.05). One standard deviation increase in daily sedentary time was prospectively associated with lower body mass index (ß = -1.22 kg/m2, 95% CI: -2.02, -0.42), waist circumference (ß = -2.39 cm, 95% CI: -4.03, -0.75), and WHtR (ß = -0.014, 95% CI: -0.024, -0.004). Sedentary time at 16 years was not associated with changes in body composition from 16 to 23 years. CONCLUSIONS: Sedentary behavior in adolescence is not adversely associated with body composition profiles in early adulthood. IMPACT: Little is known about the effect of device-measured sedentary behavior on body composition during the transition from adolescence to early adulthood. Among participants in the Santiago Longitudinal Study, more accelerometer-measured sedentary time during adolescence was associated with lower BMI, waist circumference, and waist-to-height ratio in early adulthood though point estimates were generally small in magnitude. Sedentary behavior in adolescence was not detrimentally associated with healthy body composition profiles in early adulthood. Public health interventions aimed at reducing obesity rates could consider other behaviors, such as physical activity and healthy diet, instead of sitting time.

Iron supplementation given to nonanemic infants: neurocognitive functioning at 16 years.

OBJECTIVE: There is concern that high iron uptake during the critical period of early brain development carries potential risks, especially for nonanemic infants. This study examined the neurocognitive functioning of 16-year-olds who were nonanemic as infants and received iron supplementation. METHODS: We studied 562 Chilean adolescents (M 16.2 years; 52.7% female) who participated in a randomized controlled iron supplementation trial in infancy. Between 6 and 12 months, 346 consumed an iron-fortified formula (12.7 Fe mg/L) or, if primarily breastfed, liquid vitamins with 15 mg elemental iron as ferrous sulfate, and 216 consumed unmodified cow milk without iron or liquid vitamins without iron if primarily breastfed. RESULTS: Compared to adolescents in the no-added iron condition in infancy, those in the iron-supplemented condition had poorer visual-motor integration, quantitative reasoning skills, and incurred more errors on neurocognitive tasks. Consuming larger amounts of iron-fortified formula in infancy was associated with lower arithmetic achievement. Of adolescents who had high hemoglobin at 6 months (Hb ≥ 125 g/L), those in the iron supplemented condition had poorer performance on arithmetic, quantitative reasoning, and response inhibition tests than those in the no-added iron condition. Of adolescents who had marginally low 6-month hemoglobin (Hb > 100 and < 110 g/L), those who received no-added iron incurred more errors on a visual searching task than those in the iron-supplemented condition. CONCLUSION: The physiologic need for iron during the period of rapid and critical brain development in young infants should be considered vis-à-vis the risks associated with supplementing nonanemic infants with high levels of iron.Clinical Trials number: NCT01166451.

Iron Deficiency in Infancy and Sluggish Cognitive Tempo and ADHD Symptoms in Childhood and Adolescence.

OBJECTIVE: To determine whether iron deficiency in infancy is associated with sluggish cognitive tempo (SCT) or attention-deficit/hyperactive-impulsive (AD-HI) symptoms in childhood and adolescence, and whether such behaviors contribute concurrently and predictively to lower verbal and mathematical abilities. METHOD: Chilean children (N = 959; 50% male, of Spanish or indigenous descent from working-class backgrounds) were rated by mothers for SCT or AD-HI symptoms at ages 5, 10, and 16 years. Children completed standardized tests assessing verbal and mathematical abilities at ages 5, 10, and 16. At ages 12 and 18 months, children were assessed for iron deficiency. RESULTS: Adjusting for a comprehensive panel of covariates, greater severity of iron deficiency in infancy was associated with more frequent SCT and AD-HI symptoms at all ages studied. Most effects of iron deficiency on children's verbal and math skills were indirect, mediated through AD-HI behaviors. Children's AD-HI symptoms related to lower verbal and math test scores within age and across age. CONCLUSIONS: The long-term associations found between infant iron deficiency and SCT and AD-HI behaviors suggest that the neurodevelopmental alterations that stem from postnatal iron deficiency might play an etiological role in the development of ADHD. Screening for early-life nutritional deficiencies among children with SCT or ADHD symptoms might prove useful, and behavioral screening of children with a history of iron deficiency seems warranted. Interventions that support brain development after early nutritional deprivation also would be beneficial.

Early-life adversity is associated with poor iron status in infancy.

Exposure to early-life adversity (ELA) and iron deficiency early in life are known risk factors for suboptimal brain and socioemotional development. Iron deficiency may arise from and co-occur with ELA, which could negatively affect development. In the present study, we investigated whether ELA is associated with iron deficiency in infants receiving no iron supplementation. This study is a secondary analysis of extant data collected in the 1990s; participants were healthy infants from working-class communities in Santiago, Chile (N = 534, 45.5% female). We measured stressful life events, maternal depression, and low home support for child development during infancy and assessed iron status when the infant was 12 months old. Slightly more than half of the infants were iron-deficient (51%), and 25.8% were iron-deficient anemic at 12 months. Results indicated that ELA was associated with lower iron levels and iron deficiency at 12 months. The findings are consistent with animal and human prenatal models of stress and iron status and provide evidence of the association between postnatal ELA and iron status in humans. The findings also highlight a nutritional pathway by which ELA may impact development and present a nutritionally-focused avenue for future research on ELA and psychopathology.

Young adult outcomes associated with lower cognitive functioning in childhood related to iron-fortified formula in infancy.

Objective: This study examined how the lower cognitive skills in children who consumed iron-fortified formula in infancy relate to outcomes in young adulthood.Methods: Participants were 443 Chilean young adults (M age = 21.2y, 55% female) who took part in a randomized controlled iron-deficiency anemia preventive trial during infancy (6-12 m). Slightly over half of participants (n = 237) received iron-fortified formula (12.7 mg/L) and 206 received a low-iron formula (2.3 mg/L). Spatial memory, IQ, and visual-motor integration were measured at age 10, and neurocognition, emotion regulation, educational level, and attainment of adult developmental milestones were assessed at age 21.Results: Consumption of iron-fortified formula in infancy was associated with poorer performance on neurocognitive tests in childhood, and these effects related to poorer neurocognitive, emotional, and educational outcomes in young adulthood. Dosage effects associated with consumption of iron-fortified formula were found for lower educational attainment and, marginally, slower mental processing. Those who received iron-fortified formula and had low age 10 cognitive abilities performed most poorly on neurocognitive tests at age 21.Conclusion: Findings suggest that the long-term development of infants who consume iron-fortified formula may be adversely affected.Clinical Trials number: NCT01166451.

Associations between adverse home environments and appetite hormones, adipokines, and adiposity among Chilean adolescents.

Little is known regarding the relationship between adverse home environments and hormones important in regulation of appetite and their impact on obesity in children and adolescents. In this study, we examined the impact of socioeconomic economic status, family stress and maternal depressive symptoms on appetite hormones, adipokines and adiposity. To determine whether adverse home environments in childhood and adolescence relate to adiposity in adolescence and disruptions in appetite hormones and adipokines, specifically lower levels of adiponectin and ghrelin and elevated levels of leptin and orexin. Adversity in the home (maternal depressive symptoms, family stress, socioeconomic disadvantage) was measured in the households of 593 Chilean youth at age 10 years (52.3% male) and in 606 youth at 16 years. At 16 years, participants provided fasting blood samples for assessment of adipokines and appetite hormones. Waist-to-height ratio was used to assess central adiposity. Correlational analyses examined associations between continuous levels of adversity in childhood and adolescence and appetite hormones and adiposity in adolescence. Multinomial logistic regressions compared hormone levels by tertiles of adversity. Participants were 52% male, with average age at the 16 years hormone assessment being 16.8 (n = 606, SD = 0.26). Those with highest maternal depression at age 10 had lower adiponectin OR = 0.95 [95% CI: 0.91, 0.99], p = 0.005) and ghrelin levels (OR = 0.98 [95% CI: 0.98, 1.00), p = 0.022) than those in the lowest maternal depression group at age 16. Those with the highest family stress at 16 years had lower adiponectin levels (OR = 0.93 [95% CI: 0.89, 0.98), p = 0.004) and higher central adiposity (OR = 1.05 [1.01, 1.08], p = 0.009) than the lowest family stress group. There were no significant associations found between socioeconomic status at either 10 or 16 years and appetite hormones. Results add new evidence regarding the relationship between household adversity to appetite hormones and adipokines, with the most consistent results for adiponectin. Current findings suggest that the relationship between home environment and adipokines and appetite hormones may play a role in altered adiposity in children and adolescents.

Resolving early obesity leads to a cardiometabolic profile within normal ranges at 23 years old in a two-decade prospective follow-up study.

Obesity is the most important predisposing factor for cardiovascular disease and type-2 diabetes. We explored the relationship between the age at onset of obesity and selected cardiometabolic parameters in young adults. Longitudinal study of n = 1,039 participants (48% males) in their early twenties. BMI was measured at birth, 1-5-10-12-14-16-23 years. BMI trajectories were interpolated. Five groups were identified: never obese (never-OB); early childhood obesity transitioning to non-obesity before adolescence (former-OB); obesity starting in preadolescence transitioning to non-obesity as adolescents (transient-OB); obesity from adolescence into early adulthood (recent-onset-OB); participants who were obese in early childhood and remained obese into adulthood (persistent-OB). Waist circumference (WC), blood pressure, lipids, glucose, and insulin were measured at 23 years. HOMA-IR and the Metabolic Syndrome Risk Z-Score were estimated. In the sample, 47% were obese during at least one time-point. Mean obesity duration was 20.7 years, 8.5 years, 6.2 years, and 3.3 years in persistent-OBs, recent-onset-OBs, former-OBs, and transient-OBs, respectively. The cardiometabolic profile was more adverse in recent-onset-OBs (12%) and persistent-OBs (15%) compared to never-OB participants (53%). Although former-OBs (15%) and transient-OBs (4%) had higher WC values than never-OBs, no differences were seen in other biomarkers. Both persistent and recent-onset obesity led to a cardiometabolic profile of risk in early adulthood, as suggested by values of WC, HOMA-IR, and hs-CRP above normal limits and HDL-chol values below normal limits. Participants who had obesity in early childhood or preadolescence but transitioned to a non-obesity status had a cardiometabolic profile similar to participants who were never obese and within normal limits. Obesity leads to risky values in a number of cardiometabolic biomarkers in young adulthood independent of age at obesity onset. Likewise, overcoming obesity during the pediatric age leads to a cardiometabolic profile within normal ranges at 23 years of age.

Iron deficiency in infancy and neurocognitive and educational outcomes in young adulthood.

This study examines the extent to which iron deficiency in infancy contributes to adverse neurocognitive and educational outcomes in young adulthood directly and indirectly, through its influence on verbal cognition and attention problems in childhood. Young adults (N = 1,000, M age = 21.3 years, 52% female; of Spanish or indigenous descent) from working-class families in Santiago, Chile, completed instruments assessing memory, processing speed, mental flexibility, and educational attainment. Iron status was assessed at ages 6, 12, and 18 months, and verbal intelligence, inattention, and sluggish cognitive tempo (SCT) symptoms were assessed at age 10. Results indicated that young adults who had iron-deficiency in infancy had poor executive control at age 21. Severity of iron deficiency during infancy was associated with lower verbal IQ and more frequent inattention and SCT symptoms in childhood, and with lower educational attainment in young adulthood through its effect on inattention. No additional indirect effects were found. Interventions directed toward improving cognitive and attention deficits linked to early-life iron deficiency appear warranted and could alter the course to adult functioning. Further research on the impact of such interventions would be helpful. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Mother-Adolescent Discrepancies in Ratings of Adolescents' Adjustment: Associations with Maternal Mental Health and Family Factors.

OBJECTIVE: Many children and adolescents are assessed for potential psychological and behavioral problems through the parent-completed Child Behavior Checklist (CBCL) and Youth Self-Report (YSR) questionnaires. However, because these assessments are based on individual reports, they are subject to disagreement. This study considered multiple family factors and aspects of mothers' mental health in discrepancies between mothers' and youths' ratings on the CBCL and YSR. METHOD: This study involved 926 mothers and their adolescent children (48.7% female children, mean age = 14.4 years) who completed the CBCL and YSR questionnaires, respectively. RESULTS: Mothers who experienced more severe mental health problems reported more internalizing symptoms of their adolescent relative to the adolescent's ratings. CONCLUSION: Findings indicate that mothers' poor mental health is related to their reports of more frequent psychological problems in their adolescents. To verify the accuracy of maternal reports, additional raters and additional methods, such as behavioral observation and clinical interview, would be helpful.

Associations Among Household Chaos, School Belonging and Risk Behaviors in Adolescents.

We examined the associations between adolescent risk behaviors and household chaos, and whether associations varied by adolescents' sense of school belonging. We collected data from 801 Chilean adolescents from working-class families (M age 16.2 years). Approximately, one-quarter of participants reported past-month cigarette use, and 8% and 9% reported past-month binge drinking and marijuana use, respectively. More than half of youth reported having sex (52%), 23% of youth reported having unprotected sex at their last encounter, and 14% reported having multiple sex partners. Within the past year, 16%, 36%, and 23% reported carrying a weapon, physically attacking someone, and threatening to physically hurt someone, respectively. Greater household chaos was related to increased odds of each risk behavior except unprotected sex. These associations did not vary significantly by level of school belonging. Results are compared to previously reported results using a U.S., largely Latinx sample in attempts to replicate findings across culture and context.

Risk taking, sensation seeking and personality as related to changes in substance use from adolescence to young adulthood.

INTRODUCTION: This study examined changes in substance use from adolescence to young adulthood as related to adolescents' risk taking, sensation seeking, antisocial activities, and personality traits. METHODS: Chilean youth (N = 890, 52% female) were studied in adolescence (14.5 and 16.2 years) and young adulthood (M age 21.3 years). Risk taking was assessed via a laboratory-based performance task (Balloon Analogue Risk Task), and self-administered questionnaires assessed sensation seeking, antisocial behaviors, personality and substance use. RESULTS: Frequent involvement in sensation seeking and antisocial activities were associated with increased odds of continued marijuana use from adolescence to young adulthood and of illicit substance use at young adulthood. High risk taking was associated with a reduced likelihood of discontinuing marijuana use at young adulthood, and high agreeableness and conscientiousness were associated with reduced likelihood of new onset marijuana use and illicit substance use at young adulthood. CONCLUSIONS: Results highlight specific risk-taking tendencies and personality characteristics that relate to initiating, continuing, or discontinuing substance use at entry into adulthood. Sensation seeking and involvement in antisocial activities were the two foremost risk factors for continued use, which is a forecaster of drug dependence. Findings suggest potential prevention and intervention targets for abstaining from or discontinuing substance use as youth transition to adulthood.

Childhood socioeconomic hardship, family conflict, and young adult hypertension: The Santiago Longitudinal Study.

OBJECTIVE: Stress derived from socioeconomic disadvantage can be damaging to mental and physical health. This study uses longitudinal data on a large prospectively studied cohort to examine how socioeconomic hardship during childhood leads to hypertension in young adulthood by its effects on family conflict, anxiety-depression, and body mass. METHOD: Data are from 1,039 participants of the Santiago Longitudinal Study who were studied in childhood (M age 10 years), adolescence (14-17 years), and young adulthood (21-26 years). As young adults, 26% had elevated blood pressure or hypertension. RESULTS: Children from more economically disadvantaged families experienced higher levels of family conflict, which related to significant increases in anxiety-depression and body mass over time, both of which were directly linked to hypertension in young adulthood. CONCLUSIONS: Findings provide an understanding of how early-life adversity associated with socioeconomic hardship manifests as stress-related health problems in adulthood. Intervention efforts that target overweight/obesity and anxiety and depression that stem from childhood poverty might be useful for reducing the socioeconomic disparities in adult health.

BMI Trajectories from Birth to 23 Years by Cardiometabolic Risks in Young Adulthood.

OBJECTIVE: The aim of this study was to investigate whether the level, rate, and acceleration of BMI growth differ according to the presence or absence of adult cardiometabolic (CM) risks. METHODS: BMI was measured in 1,000 Chileans at nine time points from birth to 23 years, and metabolic syndrome and its components were assessed at young adulthood. BMI growth was analyzed in the following three developmental periods: birth to 6 months, 6 months to 5 years, and 5 to 23 years. RESULTS: Individuals with CM risks had a specific constellation of early-life growth (faster growth after infancy, lower BMI decline approaching age 5, absence of a definitive BMI nadir in early childhood, higher 5-year BMI) and distinct young adult growth (larger BMI increases from childhood to young adulthood and lower levels of expected growth deceleration approaching young adulthood). Those with CM risks also attained BMI ≥ 25 at significantly younger ages than those absent risks (metabolic syndrome: 12.3 years vs. 20.1 years; hyperglycemia: 13.1 years vs. 18.9 years; hypertension: 13.2 years vs. 19.4 years; hypertriglyceridemia: 14.3 years vs. 19.5 years; inflammation: 15.9 years vs. 20.6 years). CONCLUSIONS: Larger and faster increases in BMI and a failure of BMI growth to decline or decelerate at specific developmental periods distinguished individuals who would and would not have adult CM risks.

Maternal Depression Trajectories Relate to Youths' Psychosocial and Cognitive Functioning at Adolescence and Young Adulthood.

This study evaluated how patterns of mothers' depressive symptoms across their child's childhood relate to children's psychosocial adjustment at adolescence and young adulthood and to cognitive functioning at adolescence. Depressive symptoms were measured in 1,273 mothers when their children were 1, 5, 10, and 14.6 years of age. Children (53.5% male; n = 1,024) completed the Youth Self-Report at adolescence (M = 14.6y), and the Adult Self-Report in young adulthood (M = 20.5y; n = 817) to assess internalizing and externalizing symptoms. Adolescents also completed standardized cognitive tests to assess verbal and mathematical skills. Growth mixture modeling analyses identified four patterns of maternal depressive symptom trajectories: infrequent (55%), increasing at adolescence (20%), decreasing at adolescence (14%), and chronic severe (11%). Results indicated that exposure to maternal depression of any duration, severity or time period during childhood portended higher levels of externalizing and attention problems at both adolescence and adulthood and higher levels of internalizing problems at adulthood. Adolescents whose mothers had chronic severe depressive symptoms had lower language, vocabulary, reading comprehension and mathematical test scores than youth whose mothers had stable infrequent depressive symptoms. Findings illustrate the significance and long-term ramifications of mothers' depressed mood for their children's mental and psychosocial health into adulthood. Findings also demonstrate that the lower cognitive abilities among children of severely depressed mothers persist beyond childhood and pertain to a broad range of cognitive abilities.

Sensitive periods for psychosocial risk in childhood and adolescence and cardiometabolic outcomes in young adulthood.

Greater psychosocial risk in childhood and adolescence predicts poorer cardiometabolic outcomes in adulthood. We assessed whether the timing of psychosocial risk from infancy through adolescence predicts cardiometabolic outcomes in young adulthood. Young adults and their mothers participated in a longitudinal study beginning in infancy in Santiago, Chile (N = 1040). At infancy, 5 years, 10 years, and adolescence, mothers reported on depressive symptoms, stressful experiences, support for child development in the home, father absence, parental education, and socioeconomic status (SES) to create a psychosocial risk composite at each time point. Young adults (52.1% female; 21-27 years) provided fasting serum samples and participated in anthropometric and blood pressure (BP) assessments, including a dual-energy X-ray absorptiometry (DXA) scan for measuring body fat. Greater infant psychosocial risk was associated with a greater young adult metabolic syndrome score (ß = 0.07, 95% confidence intervals (CI): 0.01 to 0.13, p = 0.02), a higher body mass index and waist circumference composite (ß = 0.08, 95% CI: 0.03 to 0.13, p = 0.002), and a higher body fat (DXA) composite (ß = 0.07, 95% CI: 0.01 to 0.12, p = 0.02). No psychosocial risk measure from any time point was associated with BP. Infant psychosocial risk predicted cardiometabolic outcomes in young adulthood better than psychosocial risk at 5 years, 10 years, or adolescence, mean of psychosocial risk from infancy through adolescence, and maximum of psychosocial risk at any one time. Consistent with the Developmental Origins of Health and Disease model, findings suggest that infancy is a sensitive period for psychosocial risk leading to poorer cardiometabolic outcomes in young adulthood.

Adolescent Internalizing, Externalizing, and Social Problems Following Iron Deficiency at 12-18 Months: The Role of Maternal Responsiveness.

This study tested whether maternal responsiveness moderated or mediated pathways from iron deficiency (ID) at 12-18 months to adolescent behavior problems. Participants were part of a large Chilean cohort (N = 933). Iron status was assessed at 12 and 18 months. Maternal responsiveness was assessed at 9 months and 5 years. Parents reported their child's symptomology at 5 years, 10 years, and adolescence (11-17 years; M = 14.4). Structural equation modeling identified a previously unrecognized pathway by which child externalizing problems and negative maternal responsiveness at 5 years mediated associations between ID at 12-18 months and adolescent internalizing, externalizing, and social problems. Positive maternal responsiveness in infancy did not buffer those with ID anemia from developing 5-year internalizing problems.

Effect of Infant Iron Deficiency on Children's Verbal Abilities: The Roles of Child Affect and Parent Unresponsiveness.

BACKGROUND: Infants who are iron-deficient anemic seek and receive less stimulation from their caregivers, predisposing such children to be functionally isolated. OBJECTIVES: To test the sequence whereby iron deficiency in infancy contributes to children's disengagement from the environment, which reduces parent stimulation which, in turn, contributes to children's poor verbal skills. METHODS: Chilean children (N = 875, 54% male) were studied, 45% of whom were iron deficient or iron-deficient anemic in infancy. We used structural equation modeling to test the sequence outlined above and to examine the effect of infant iron status on children's verbal performance at ages 5 and 10 years including the roles of child and parent intermediate variables. RESULTS: Severity of iron deficiency in infancy was associated with higher levels of children's dull affect and social reticence at 5 years (ß = .10, B = .26, SE = .12, p < .05), and these behaviors were associated with parent unresponsiveness (ß = .29, B = .13, SE = .03, p < .001), which related to children's lower verbal abilities at age 5 (ß = - .29, B = - 2.33, SE = .47, p < .001) and age 10 (ß = - .22, B = - 3.04, SE = .75, p < .001). An alternate model where poor iron status related directly to children's verbal ability was tested but not supported. CONCLUSIONS: Findings support functional isolation processes resulting from a nutritional deficiency, with iron-deficient anemic infants showing affective and behavioral tendencies that limit developmentally stimulating caregiving which, in turn, hinder children's verbal abilities.