Comparison of multiple measures of ADHD symptomatology: a multivariate genetic analysis

The phenotypic and genetic interrelationships underlying ADHD symptomatology assessed by various instruments were examined on a sample of 735 male and 819 female same-sex twin pairs, aged 8 to 16 years, participating in the first phase of the Virginia Twin Study of Adolescent Behavioral Development (VTSABD). Multivariate analyses were applied to parental and teacher ratings from an investigator-based interview, the CAPA, and three questionnaires (the CBCL and the Rutter Parent and Teacher Scales). Results from patterns of intercorrelations and factor analyses of maternal measures suggested that at the phenotypic level, these assessed the same underlying behavioural construct, which differed from other emotional and behavioural constructs. However, genetic analyses showed that in addition to a common factor underlying the expression of ADHD as assessed across the range of measures, additional genetic factors were identified that were method- and rater-specific. The findings suggest that although the investigator-based interview and the behavioural checklists tap similar aspects of ADHD behaviour, there is additional rater-specific variance.     

Assessing exposure to violence using multiple informants: application of hierarchical linear model

The present study assesses the effects of demographic risk factors on children's exposure to violence (ETV) and how these effects vary by informants. Data on exposure to violence of 9-, 12-, and 15-year-olds were collected from both child participants (N = 1880) and parents (N = 1776), as part of the assessment of the Project on Human Development in Chicago Neighborhoods (PHDCN). A two-level hierarchical linear model (HLM) with multivariate outcomes was employed to analyze information obtained from these two different groups of informants. The findings indicate that parents generally report less ETV than do their children and that associations of age, gender, and parent education with ETV are stronger in the self-reports than in the parent reports. The findings support a multivariate approach when information obtained from different sources is being integrated. The application of HLM allows an assessment of interactions between risk factors and informants and uses all available data, including data from one informant when data from the other informant is missing.     

Depressive symptoms in children and adolescents: changing aetiological influences with development

BACKGROUND: Evidence suggests that depressive symptoms become increasingly heritable as children grow into adolescence. However, the literature is not entirely consistent in this respect and existing longitudinal twin studies have examined changes within adolescence only. METHOD: Parent and self-report questionnaire data were used to examine the genetic and environmental influences on depressive symptoms in a UK sample of 670 twin pairs aged 5-17. Age effects were examined cross-sectionally and longitudinally using data collected over a 3-year period. RESULTS: Cross-sectional analyses showed that shared environmental effects had significant influence in younger children but not in adolescence, when depression scores were significantly more heritable. The results of these cross-sectional analyses were supported when two waves of parent-report data collected over three years were analysed. Significant new genetic influences emerged in adolescence but no new shared environmental influences. Some sex differences were found, with girls showing greater genetic influence than boys, but only from parent-report data. CONCLUSIONS: These findings support and extend earlier work which has shown increasing genetic influence on depressive symptoms as children grow into adolescence.     

Genetic influences on early word recognition abilities and disabilities: a study of 7-year-old twins

BACKGROUND: A fundamental issue for child psychology concerns the origins of individual differences in early reading development. METHOD: A measure of word recognition, the Test of Word Reading Efficiency (TOWRE), was administered by telephone to a representative population sample of 3,909 same-sex and opposite-sex pairs of 7-year-old twins. Analyses allowing for sex differences in aetiology were used to estimate the extent to which genetic and environmental influences contribute to normal variation in word recognition and word recognition difficulties, defined by scores below the 5th and 10th percentiles of the unselected sample. RESULTS: Both normal variation in word recognition and impaired word recognition abilities were substantially heritable (h2 = .65-.67; h(g)2 = .37-.72). Environmental influences were primarily shared between twins, rather than specific to each individual, and small to moderate in magnitude. There was evidence for qualitative sex differences. Quantitative sex differences were also suggested at the extremes, with genetic influences being more important as a cause of reading difficulties in boys than in girls. CONCLUSIONS: These findings indicate that early individual differences and impairments in word recognition are principally influenced by genetic factors and may involve partly distinct genetic or environmental effects in boys and girls. Crucially, they also provide evidence that reading impairments are linked genetically to the normal distribution. Genetic risk for early impairments in word recognition is continuous rather than discrete.     

Towards a family process model of maternal and paternal depressive symptoms: exploring multiple relations with child and family functioning

BACKGROUND: Research has focused on maternal dysphoria and child adjustment. However, family process models indicate gaps in the study of paternal dysphoria, broader family functioning, and diverse child outcomes. METHOD: A community sample of 235 mothers and fathers of kindergarten children completed measures of depressive symptoms, family functioning and child adjustment. Teachers also provided measures of child adjustment. RESULTS: Supportive of pervasive effects even in a community sample, increased parental depressive symptomatology was related to increased marital conflict, insecure marital attachment, less parental warmth, more psychological control in parenting, and multiple child problems. Child gender moderated child outcomes differently for paternal and maternal dysphoria. Marital relations, but not parenting, mediated child outcomes. CONCLUSIONS: Marital problems may be especially reactive to parental depressive symptomatology, so that mediational processes affecting child functioning become evident even in family contexts of relatively low risk.     

Developmental trajectories of depressive symptoms from early childhood to late adolescence: gender differences and adult outcome

BACKGROUND: Limited information is available on gender differences and young-adult poor outcome in children and adolescents following distinct developmental trajectories of depressive symptoms. METHODS: Parent information on depressive symptoms of 4- to 18-year-olds from an ongoing Dutch community-based longitudinal multiple-cohort study (N = 2,076) was used to estimate trajectories from semi-parametric mixture models. The identified trajectories were used to predict depressive problems, general mental health problems, referral to mental health care, and educational attainment in young adulthood. RESULTS: In both genders six distinct developmental trajectories were identified. Gender differences existed not only in level, but also in shape and timing of onset of depressive problems. Only in girls was a chronic trajectory of early childhood-onset depression identified. In both boys and girls a group with increasing levels of depressive symptoms was identified that reached a high level around adolescence, although boys showed an earlier onset. Two decreasing trajectories were found in boys, one reaching normative levels of depressive symptoms around late childhood and one around mid-adolescence, while none was found for girls. Individuals who followed elevated trajectories during their whole childhood or starting at adolescence had significantly more depressive and other mental health problems in young adulthood compared to those who followed normative trajectories. Boys in these elevated trajectories showed lower educational attainment, while girls were more likely to have been referred to mental health care. CONCLUSIONS: This study shows the value of estimating growth-mixture models separately for boys and girls. Girls with early childhood or adolescence-onset depressive problems and boys with depressive problems during childhood or starting in adolescence are especially at risk for poor outcome as young adults and should be considered candidates for intervention.     

Psychosocial correlates of depressive symptoms among 12-14-year-old Norwegian adolescents

BACKGROUND: The aim of the study was to examine the relationships between various psychosocial factors and depressive symptoms in early adolescence. METHODS: A representative sample of 2,465 12-14-year-old adolescents comprising 50.8% girls and 49.2% boys, with a mean age of 13.7 years, was recruited in two counties in Norway. The participation rate was 88.3%. Depressive symptoms were measured by the Mood and Feelings Questionnaire (MFQ). RESULTS: Correlations between the total sum of stressful events/daily hassles and the total sum of MFQ were moderately high, rs = .49 and rs = .53, respectively. Depressive symptoms were more strongly correlated with school-related stress among boys than girls, whereas the correlation between daily hassles and depressive symptoms was higher for girls than boys. The results of univariate analyses showed significantly higher mean total MFQ scores among adolescents not living with both natural parents, those who had moved more than twice and those with more than 3 siblings orhaving fewer than 2 close friends. Further, adolescents from Third World societies and adopted adolescents, those from lower SES groups, having unemployed parents or living in coastal areas had higher mean depressive symptom scores. The results of multiple regression analyses yielded the following six significant predictors of total MFQ scores in order of importance: Sum of daily hassles and sum of stressful life events, gender, number of friends, ethnicity and mother's employment status. Altogether, these variables accounted for 43% of the total variance in MFQ scores. CONCLUSIONS: It is concluded that these psychosocial predictors should be addressed when assessing depressive symptoms in early adolescence. The findings of the study are discussed in view of previous research in the field and their clinical significance.     

Children's skin conductance reactivity as a mechanism of risk in the context of parental depressive symptoms

BACKGROUND: Children's physiological reactivity was examined as a moderator of relations between parental dysphoria and child adjustment problems, addressing gaps in the study of child characteristics as risk processes. METHOD: One hundred fifty-seven children (86 boys, 71 girls) were assessed twice over a two-year interval. Skin conductance level reactivity (SCLR) to inter-adult argument and problem-solving tasks was observed. RESULTS: SCLR moderated longitudinal predictions of children's internalizing, externalizing and social adjustment problems, especially for paternal rather than maternal dysphoria. Higher SCLR predicted greater vulnerability to parental depressive symptomatology. CONCLUSIONS: Findings highlight that individual differences in children's physiological reactivity may relate to risk for adjustment problems in the context of parental depressive symptoms.     

The development of impulsivity,fearfulness, and helpfulness during childhood: patterns of consistency and change in the trajectories of boys and girls

BACKGROUND: The objective of the present study was to describe the development of boys and girls during the elementary-school years on three dimensions that conceptually and empirically represent risk for maladjustment. METHOD: Every year between kindergarten and grade six, teachers rated the impulsivity, fearfulness, and helpfulness dimensions among a sample of 1,865 children representative of kindergarten boys and girls in the province of Quebec (Canada) in 1986-87. A group-based trajectory method was used to 1) identify groups of boys and girls following distinct-level trajectories of behaviours (on each dimension) during the elementary-school years; 2) estimate the proportion of children in each of the identified trajectory groups; and 3) estimate the patterns of consistency and variations in trajectories. RESULTS: The results indicated that the best models comprised three distinct-level trajectory groups on fearfulness and helpfulness (a low, moderate, and high group) and four distinct-level trajectory groups on impulsivity. The helpfulness and fearfulness trajectory groups were generally more stable than the impulsivity groups. The broad patterns of development were similar across sexes. However, there were more boys on the higher impulsivity trajectories and low helpfulness trajectory, while there were more girls on the high fearfulness trajectory. CONCLUSION: We found that behavioural consistency over middle childhood varied across trajectory groups and across dimensions, and we identified sex differences in the distribution of children in the different trajectory groups that may reflect gender-specific risks for psychopathology.     

A prospective study of maternal anxiety, perceived stress, and depressive symptoms in relation to infant cognitive development

Aim

Our objective was to examine the associations between maternal psychological health (trait anxiety, perceived stress, and depressive symptoms) during pregnancy or postpartum and infant visual, language, motor, and overall cognitive development.

Study Design and Methods

In the prospective Pregnancy, Infection, and Nutrition Study (2001-2006), central North Carolina women completed self-administered questionnaires during pregnancy to assess trait anxiety and depressive symptoms. An in-person interview assessed maternal perceived stress and depressive symptoms in the 4th postpartum month. Infant development was assessed at 12 months using the Mullen Scales of Early Learning (n = 358). Multiple linear regression with restricted cubic splines was used to examine potential non-linear associations between trait anxiety, perceived stress, and depressive symptoms in relation to Mullen sub-scales and Composite scores.

Results

Increasing maternal anxiety was associated with poorer overall cognition (adjusted β for Composite = − 0.2, 95% CI: −0.4, 0.0). Postpartum stress was positively associated with language development and general cognition (adjusted β for Expressive Language = 0.2, 95% CI: 0.0, 0.4; adjusted β for Composite = 0.3, 95% CI: 0.0, 0.6). Elevated depressive symptoms throughout pregnancy and postpartum were associated with better fine motor skills (adjusted β = 9.7, 95% CI: 3.9, 15.5). Anxiety, postpartum depressive symptoms and stress were associated with gross motor skills in a non-linear fashion, as were postpartum depressive symptoms and stress with expressive language.

Conclusions

Maternal trait anxiety, depressive symptoms and stress had little negative influence on infant cognitive development. In fact, moderate psychosocial distress may slightly accelerate motor development in particular, and some aspects of language.