Association between a marker for prenatal testosterone exposure and externalizing behavior problems in children

A Systematic Review and Meta-analysis of Prenatal, Birth, and Postnatal Factors Associated with Attention-Deficit/Hyperactivity Disorder in Children

Previous studies have shown mixed results on the relationship between prenatal, birth, and postnatal ("pregnancy-related") risk factors and attention-deficit/hyperactivity disorder (ADHD). We conducted meta-analyses to identify potentially modifiable pregnancy-related factors associated with ADHD. A comprehensive search of PubMed, Web of Science, and EMBASE in 2014, followed by an updated search in January 2021, identified 69 articles published in English on pregnancy-related risk factors and ADHD for inclusion. Risk factors were included in the meta-analysis if at least three effect sizes with clear pregnancy-related risk factor exposure were identified. Pooled effect sizes were calculated for ADHD overall, ADHD diagnosis, inattention, and hyperactivity/impulsivity. Odds ratios (OR) were calculated for dichotomous measures and correlation coefficients (CC) for continuous measures. Prenatal factors (pre-pregnancy weight, preeclampsia, pregnancy complications, elevated testosterone exposure), and postnatal factors (Apgar score, neonatal illness, no breastfeeding) were positively associated with ADHD overall; the findings for ADHD diagnosis were similar with the exception that there were too few effect sizes available to examine pre-pregnancy weight and lack of breastfeeding. Prenatal testosterone was significantly associated with inattention and hyperactivity/impulsivity. Effect sizes were generally small (range 1.1-1.6 ORs, -0.16-0.11 CCs). Risk factors occurring at the time of birth (perinatal asphyxia, labor complications, mode of delivery) were not significantly associated with ADHD. A better understanding of factors that are consistently associated with ADHD may inform future prevention strategies. The findings reported here suggest that prenatal and postnatal factors may serve as potential targets for preventing or mitigating the symptoms of ADHD.

Elevated level of prenatal testosterone and vitamin D3 deficiency during pregnancy, in the presence of prenatal maternal stress, and their association with the development of attention deficit hyperactivity disorder (ADHD)-like symptoms in toddlers

INTRODUCTION

To investigate the hypothesis that the presence of prenatal maternal stress, increased level of prenatal testosterone, and low level of vitamin D3 in pregnancy is associated with the development of ADHD-like symptoms in toddlers (< 2 years old).

MATERIAL AND METHODS

The study group comprised 53 pregnant women and 53 infants of these pregnancies. The population cohort of 53 pregnant women were recruited at their 35th to 37th week of pregnancy and investigated prospectively. The participants were selected through targeted selection. Maternal experience of stressful life events was assessed by stress standardised questionnaires, prenatal testosterone was determined in the mothers' saliva by using the immune enzymatic (ELISA) method, and maternal plasma D vitamin was measured using the ECLIA method, during pregnancy. When the age of the offspring was 6 months and then less than 2 years, the mothers completed the child behaviour and temperament checklist.

RESULTS

A small but statistically significant association was found between the common symptom complex of ADHD and the level of testosterone and vitamin D3, in the presence of prenatal maternal stress. Multiple regression analysis showed that maternal stressful events during pregnancy significantly predicted ADHD behaviours in offspring.

CONCLUSIONS

The study supported the hypothesis that prenatal maternal stress, increased level of prenatal testosterone, and low level of vitamin D3 during pregnancy increases the risk of development of ADHD-like symptoms in toddlers (< 2 years old). Also, the obtained results support the hypothesis that the influence of prenatal factors causes ADHD-like symptoms in offspring through a programming effect.

Maternal emotions during the pre/postnatal periods and children's sleep behaviors: The mediating role of children's behavior

BACKGROUND

We aimed to investigate the association of mother's perceived levels of depression and happiness across all trimesters of pregnancy and after delivery on their children's sleep problems, as well as examine the possible mediating effect of children's behavioral problems.

METHODS

Participants included 1257 children (54% boys, mean age = 5.74 ± 0.48 years). Pre- and postnatal maternal emotions were self-reported using a 5-point scale for happiness and a 3-point scale for depressive emotions. Children reported sleep and behavioral problems using the Child Behavior Checklist.

RESULTS

Adjusted models showed that children of women reporting depressive emotions during either the postnatal period (β = 3.07, p = 0.01) or both prenatal and postnatal periods (β = 2.91, p = 0.01) were more likely to report sleep disturbances. By contrast, children of women reporting higher levels of happiness in the second (β = -1.91, p = 0.04) and third (β = -2.27, p = 0.001) trimesters were less likely to report sleep problems.

LIMITATIONS

Differences in maternal-report of children's behaviors could reflect memory and recall bias, and maternal emotions were assessed by researcher-designed single item measures. All measures were completed by a single reporter. Other associated factors should be considered in clarifying the complex associations.

CONCLUSIONS

Maternal depressive emotions during pre- and postnatal periods were associated with an increase in children's sleep problems, while increased happiness during pregnancy was associated with a decrease in children's sleep problems. Children's behavioral problems significantly mediated these relationships. To our knowledge, this is the first study to examine the relationship between maternal pre- and postnatal emotions and children's sleep behavior in an Asian sample.

Association between tendencies for attention-deficit/hyperactivity disorder (ADHD) and the 2D:4D digit ratio: a cross-cultural replication in Germany and China

Prenatal testosterone is considered to be a possible factor contributing to the development of attention-deficit/hyperactivity disorder (ADHD) symptomatology, but findings regarding the connection between individual variations in prenatal testosterone exposure as (indirectly) indexed by the second-to-fourth digit (2D:4D) ratio and ADHD remain inconsistent. To clarify the inconsistent findings and to facilitate generalization on the association between subclinical variations in ADHD tendencies and lower 2D:4D ratios the current study applied a cross-cultural replication approach employing independent healthy adult cohorts from Germany and China. Samples from Germany and China were matched for gender and age (in each sample n_males = 96, n_females = 96; age_Germany: M = 21.47, SD = 2.55; age_China: M = 21.36, SD = 2.28). All participants filled in the Adult ADHD Self-Report Scale Symptom Checklist (ASRS) and provided hand scans to measure 2D:4D ratios. The German sample had significantly higher 2D:4D ratios than the Chinese sample but in both samples males had significantly lower 2D:4D ratios than females. The hypothesised negative association between 2D:4D ratios and ADHD tendencies was observed on a descriptive level in German and Chinese males and with one exception in Chinese females. But only in German males correlations gained significance (range: r = -0.198 to r = -0.177). The observed effect sizes are in line with former research that was conducted in samples from different cultures. In future research on the connection between testosterone and ADHD not only prenatal but also postnatal testosterone as well as possible moderators like childhood maltreatment should be taken into account.

ADHD pathogenesis in the immune, endocrine and nervous systems of juvenile and maturating SHR and WKY rats

RATIONALE

Attention-deficit/hyperactivity disorder (ADHD) is one of the most common neurobehavioural disorders with morphological and functional brain abnormalities. However, there is a growing body of evidence that abnormalities in the immune and endocrine systems may also account for the ADHD pathogenesis.

OBJECTIVES

To test ADHD pathogenesis in neurological, immune and endocrine systems, this study examined the concentrations of cytokines, chemokines, oxidative stress markers, metabolic parameters, steroid hormones and steroidogenic enzymes in the serum and/or tissues of spontaneously hypertensive rats (SHRs, animal model of ADHD) and Wistar Kyoto rats (WKYs, control animals). Moreover, the volume of the medial prefrontal cortex (mPFC) as well as the density of dopamine 2 (D2) receptor-expressing cells and tyrosine hydroxylase (TH)-positive nerve fibres in it was also elucidated.

METHODS

Peripheral blood, spleen and adrenal gland samples, as well as brain sections collected on day 35 (juvenile) and day 70 (maturating) from SHRs and WKYs, were processed by ELISA and immunohistochemistry, respectively.

RESULTS

The results show significant increases of serum and/or tissue concentrations of cytokines, chemokines and oxidative stress markers in juvenile SHRs when compared to the age-matched WKYs. These increases were accompanied by a lowered volume of the mPFC and up-regulation of D2 in this brain region. In maturating SHRs, the levels of inflammatory and oxidative stress markers were normalised and accompanied by elevated contents of steroid hormones.

CONCLUSIONS

Significant elevations of serum and/or tissue contents of cytokines, chemokines and oxidative stress markers as well as volumetric and neurochemical alterations in the mPFC of juvenile SHRs may suggest the cooperation of neurological and immune systems in the ADHD pathogenesis. Elevated levels of steroid hormones in maturating SHRs may be a compensatory effect involved in reducing inflammation and ADHD symptoms.

The Schizotypal Personality Questionnaire - Child (SPQ-C): Psychometric properties and relations to behavioral problems with multi-informant ratings

The Schizotypal Personality Questionnaire (SPQ) is one of the most widely used screening tools for schizotypy in adults. The Schizotypal Personality Questionnaire-Child version (SPQ-C) was recently developed to assess schizotypy in children and has a similar three-factor structure to the adult SPQ (i.e., Cognitive-Perceptual, Interpersonal-Affective, and Disorganization). However, few studies to date have reported on the psychometric properties and the usefulness of the SPQ-C in Eastern populations, including Mainland China. This study presents the first psychometric assessment of the Chinese SPQ-C in Mainland China. Exploratory factor analysis and confirmatory factor analysis were used to assess the factor structure of the SPQ-C in 1668 children (M = 12.10, SD = 0.60 years) from the China Jintan Child Cohort Study. Our findings document a three-factor structure and partial measurement invariance across residential location and gender, replicating the psychometric properties of the SPQ-C in English. The Chinese SPQ-C further correlates with standard behavioral problems (i.e., Child Behavior Checklist, Youth Self-Report and Teacher Report Form), demonstrating construct validity and utility as a child psychopathology assessment tool. Our findings provide the first robust psychometric evidence for a three-factor structure of the Chinese SPQ-C in a large Mainland Chinese sample, and suggest that the SPQ-C is suitable as a screening tool for schizotypy in community children who may be at risk for behavioral problems and later psychosis.

Digit ratio (2D:4D) and behavioral symptoms in primary-school aged boys

The second-to-forth digit length ratio (2D:4D) is considered to be a biomarker for intrauterine androgen levels. It is associated with adult and child mental health problems, primarily with behavioral symptoms and predominantly in males. Using a cross-sectional design, we examined whether 2D:4D was associated with conduct disorder (CD) symptoms in 138 primary-school aged children (54% boys, M_age = 7.70 years) and considered child sex as a moderating factor. Children's digit lengths were measured from hand scans and mothers rated the behavioral/emotional symptoms of their child. The regression analyses revealed that 2D:4D ratios were associated with behavioral symptoms in boys (β = -0.260, p = 0.026), but not in girls (β = -0.040, p = 0.762). Child emotional symptoms, analyzed as a control, were not significantly correlated with 2D:4D. In conclusion, prenatal brain hyperandrogenization - operationalized by the 2D:4D biomarker - could result in behavioral symptoms in boys at early school age, reflecting one predictor for early onset CD. Our data support the use of 2D:4D as a marker of prenatal androgen exposure.

Potential role of pre- and postnatal testosterone levels in attention-deficit/hyperactivity disorder: is there a sex difference?

OBJECTIVE

Both prenatal testosterone (T) exposure and postnatal T levels have been associated with developing neural circuitry and behavioral systems. This study examined the potential correlation between pre- and postnatal T levels and behavioral and neurocognitive profiles of children with attention-deficit/hyperactivity disorder (ADHD).

METHODS

Two hundred ADHD patients with a mean age of 8.7±2.0 years (158 boys and 42 girls) were recruited. The ratio of the length of the right index finger (2D) to that of the right ring finger (4D) (2D/4D ratio) served as a surrogate of prenatal T exposure, and postnatal T was determined using salivary T concentration. Behavioral symptoms were evaluated using the Swanson, Nolan, and Pelham - Version IV Scale for ADHD (SNAP-IV). Neurocognitive function was assessed using the Wechsler Intelligence Scale for Children - Fourth Edition (WISC-IV) and Conners' Continuous Performance Test (CPT).

RESULTS

Lower 2D/4D ratios were associated with comorbid disruptive behavior disorders (t=2.15, P=0.033) in all participants. Among the boys with ADHD, neither 2D/4D ratios nor salivary T levels were associated with behavioral symptoms or neurocognitive function. Among the girls with ADHD, the salivary T level was positively correlated with the Perceptual Reasoning Index of the WISC-IV (r=0.48, P=0.001) and the Confidence Index (r=0.37, P=0.017) and Omission Errors of the CPT (r=0.62, P<0.001).

CONCLUSION

Findings suggest that a higher prenatal T exposure is associated with a greater risk of developing disruptive behavior disorders, and T may exert differential neurocognitive effects between boys and girls with ADHD. However, the neurobiological mechanisms of T involved in the pathogenesis of ADHD warrant further investigation.

Assessment of the 2D:4D ratio in aggression-related injuries in children attending a paediatric emergency department

BACKGROUND

The 2D:4D ratio is a sexually dimorphic trait. A lower ratio is correlated with sporting prowess, successful financial trading, risk taking behaviour, aggression, and aggression-related injuries, such as the fifth metacarpal fractures.

AIMS

We aimed to assess if the ratio correlates to skeletally immature patient aggression.

METHODS

Radiology reports were searched for the terms "5th metacarpal" or "boxer". Of 537 X-rays, 142 had fractures. The mechanism of injury was recorded in 102 patients, differentiating aggressive and non-aggressive injury groups. Bone age and chronological age were recorded.

RESULTS

A clear male preponderance for aggression was identified with only 60% of non-aggressive injuries occurring in males compared to 95% in the aggression group (p < 0.001). Patients with aggression injuries were older chronologically (14.6 vs 12.7, p < 0.001) and by bone age (14.5 vs 13.0, p < 0.001). For male patients, there was no difference in the 2D:4D ratio (p = 0.94); however, for females, the difference was significant (p = 0.04).

CONCLUSIONS

Aggression injuries occur at an older age and are more common in males. In the female cohort, there was a distinct difference in digit ratio.

Relationship between acne vulgaris and attention-deficit/hyperactivity disorder symptoms in a clinical sample of women

Acne vulgaris has recently been reported to be associated with elevated rates of attention deficit/hyperactivity disorder in epidemiological studies. This report examines childhood and current attention-deficit/hyperactivity disorder symptoms in a clinical sample of female adults. Ninety-one women with acne vulgaris and 53 controls were included in this study. The aforementioned symptoms were measured in participants. No significant differences were found between patients and controls in any of the measurements. Contrary to the findings of epidemiological studies, this study did not uncover a link between acne vulgaris and attention-deficit/hyperactivity disorder

Autistic Trait, Empathy, and Attention-Deficit/Hyperactivity Symptoms in Women with Idiopathic Hirsutism

Aim:

Many psychiatric disorders, including attention-deficit/hyperactivity disorder (ADHD), disruptive behavioral disorders, autism spectrum disorders, and some psychiatric characteristics, such as poor empathizing, are regarded to be related to elevated levels of androgens or androgen sensitivity. Thus, numerous studies have investigated the potential association between androgen-related physical diseases and these psychiatric conditions. Idiopathic hirsutism (IH) is a disease characterized by an increased sensitivity of the pilosebaceous unit to circulating androgens in women. The purpose of this study was to examine whether IH has a relationship with androgen-related psychiatric conditions.

Materials and Methods:

Totally 37 females with IH and 33 healthy female controls were included in this study. Childhood and present ADHD symptoms of the participants were assessed using the Wender Utah Rating Scale (WURS) and the Adult ADHD Self-Report Scale, respectively. The Autism-spectrum quotient and the interpersonal reactivity index were used to assess autistic traits and different aspects of empathy. Hirsutism severity was measured using the Ferriman–Gallwey scoring system.

Results:

No significant difference was found between the patients and controls on psychiatric questionnaire scores, except for a trend for subjects with IH to show higher levels of the school-associated problems than controls according to WURS. The severity of hirsutism was strongly correlated with the WURS irritability and behavioral problems/impulsivity subscores and WURS total score, and moderately correlated with the WURS attentional deficit subscore.

Conclusions:

This study provides preliminary evidence that common etiological factors may be involved in both the severity of IH, ADHD, and coexisting disruptive behavioral problems.

Digit ratio (2D:4D) moderates the relationship between cortisol reactivity and self-reported externalizing behavior in young adolescent males

Although reduced cortisol reactivity to stress and increased circulating testosterone level are hypothesized to be associated with higher levels of externalizing behavior, empirical findings are inconsistent. One factor that may account for the heterogeneity in these relationships is prenatal testosterone exposure. This study examined whether the second-to-fourth digit ratio (2D:4D), a putative marker of prenatal testosterone exposure, moderates the relationships of testosterone and cortisol reactivity with externalizing behavior. Left and right hand 2D:4D and self-reported externalizing behavior were measured in a sample of 353 young adolescents (M age=11.92 years; 178 females; 79.7% African American). Saliva samples were collected before and after a stress task and later assayed for cortisol. Testosterone levels were determined from an AM saliva sample. 2D:4D interacted with cortisol reactivity to predict externalizing behavior in males, but not females. In males, low cortisol reactivity was associated with higher levels of aggression and rule-breaking behavior, but only among subjects with low 2D:4D (i.e., high prenatal testosterone). Findings suggest the importance of a multi-systems approach in which interactions between multiple hormones are taken into account. Furthermore, results demonstrate the importance of considering the organizational influence of prenatal testosterone in order to understand the activational influence of circulating hormones during adolescence.

Cohort Profile Update: The China Jintan Child Cohort Study

The China Jintan Child Cohort study began in 2004 with 1656 pre-school participants and a research focus on studying the impact of environmental exposures, such as lead, on children's neurobehavioural outcomes. This population cohort now includes around 1000 of the original participants, who have been assessed three times over a period of 10 years. Since the original IJE cohort profile publication in 2010, participants have experienced a critical developmental transition from pre-school to school age and then adolescence. The study has also witnessed an increase in breadth and depth of data collection from the original aim of risk assessment. This cohort has added new directions to investigate the mechanisms and protective factors for the relationship between early health factors and child physical and mental health outcomes, with an emphasis on neurobehavioural consequences. The study now encompasses 11 domains, composed of repeated measures of the original variables and new domains of biomarkers, sleep, psychophysiology, neurocognition, personality, peer relationship, mindfulness and family dynamics. Depth of evaluation has increased from parent/teacher report to self/peer report and intergenerational family report. Consequently, the cohort has additional directions to include: (i) classmates of the original cohort participants for peer relationship assessment; and (ii) parental and grandparental measures to assess personality and dynamics within families. We welcome interest in our study and ask investigators to contact the corresponding author for additional information on data acquisition.

Low blood zinc, iron, and other sociodemographic factors associated with behavior problems in preschoolers

Previous research supports the link among malnutrition, cognitive dysfunction, and behavioral outcomes; however, less research has focused on micronutrient deficiencies. This study investigates whether micronutrient deficiencies, specifically blood zinc and iron levels, will be associated with increased behavior problem scores, including internalizing and externalizing behaviors. 1314 Children (55% boys and 45% girls) from the Jintan Preschool Cohort in China participated in this study. Venous blood samples were collected and analyzed for zinc and iron when the children were 3-5 years old. Behavior problems were measured with the Child Behavior Checklist (CBCL), which was completed by the parents when children were in their last months of preschool (mean age 5.6 years). General linear multivariate modeling was used, with adjustment for important sociodemographic variables. The results indicate that low zinc levels alone (p = 0.024) and combined low zinc and iron levels (p = 0.022) are significantly associated with increased reports of total behavior problems. We did not find an association between low iron and behavior problems. With regards to sociodemographics, living in the suburbs is associated with increased internalizing problems, while higher mother's education and being female were associated with decreased externalizing problems. This study suggests that micronutrient deficiencies and sociodemographic facts are associated with behavior problems in preschoolers.

Breastfeeding and active bonding protects against children's internalizing behavior problems

Breastfeeding is associated with numerous health benefits to offspring and mothers and may improve maternal-infant bonding. Ample evidence suggests breastfeeding can improve child neurodevelopment, but more research is needed to establish whether breastfeeding is linked to the development of child psychopathology. This paper aims to explore the effects of both breastfeeding and mother-child interactions on child behavioral outcomes at a later age. Children from the China Jintan Child Cohort Study (N = 1267), at age six years old were assessed, along with their parents. Children who were breastfed exclusively for a period of time in the presence of active bonding were compared to those who were breastfed in the absence of active bonding as well as to children who were not exclusively breastfed, with or without active bonding. Results from ANOVA and GLM, using SPSS20, indicate that children who were breastfed and whose mothers actively engaged with them displayed the lowest risk of internalizing problems (mean = 10.01, SD = 7.21), while those who were neither exclusively breastfed nor exposed to active bonding had the least protection against later internalizing problems (mean = 12.79, SD = 8.14). The effect of breastfeeding on internalizing pathology likely represents a biosocial and holistic effect of physiological, and nutritive, and maternal-infant bonding benefits.