Prenatal testosterone increases sensitivity to prenatal stressors in males with disruptive behavior disorders

Systematic Review and Meta-analysis of the Relationship Between Exposure to Parental Substance Use and Attention-Deficit/Hyperactivity Disorder in Children

Attention-deficit/hyperactivity disorder (ADHD) is characterized by persistent patterns of inattention, hyperactivity, and impulsiveness. Among US children and adolescents aged 3-17 years, 9.4% have a diagnosis of ADHD. Previous research suggests possible links between parental substance use and ADHD among children. We conducted a systematic review and meta-analysis of 86 longitudinal or retrospective studies of prenatal or postnatal alcohol, tobacco, or other parental substance use and substance use disorders and childhood ADHD and its related behavioral dimensions of inattention and hyperactivity-impulsivity. Meta-analyses were grouped by drug class and pre- and postnatal periods with combined sample sizes ranging from 789 to 135,732. Prenatal exposure to alcohol or tobacco and parent substance use disorders were consistently and significantly associated with ADHD among children. Other parental drug use exposures resulted in inconsistent or non-significant findings. Prevention and treatment of parental substance use may have potential for impacts on childhood ADHD.

Attention-deficit/hyperactivity disorder and the menstrual cycle: Theory and evidence

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder that exhibits striking sex differences in symptoms, prevalence, and associated problems across development. Etiological factors and mechanisms underlying these sex differences remain one of the most understudied aspects of this disorder. The current paper seeks to provide a novel theoretical framework for understanding this phenomenon by reviewing evidence that females with ADHD may experience a "double whammy" of organizational and activational pubertal hormonal effects. We propose a novel theory of activational effects of cyclical circulating ovarian hormones on ADHD with increasing risk at times of rapid declines in estrogen. These declines may decrease executive function and trait control at two points of the cycle characterized by biphasic affective risk: (1) increases in approach/risk-taking behaviors at mid-cycle (periovulatory) and (2) increases in avoidance/negative affect perimenstrually. Low estrogen and control may then interact with increases in positive and negative affect, respectively, to increase hyperactivity-impulsivity symptoms post-ovulation and inattention symptoms perimenstrually. These interactions may be exacerbated by organizational pubertal effects on relatively overdeveloped limbic circuitry and adolescent-specific social pressures magnified in females with ADHD.

Longitudinal Temperament Pathways to ADHD Between Childhood and Adolescence

The current investigation extended prior cross-sectional mapping of etiological factors, transdiagnostic effortful and affective traits, and ADHD symptoms to longitudinal pathways extending from two etiological domains: polygenic and prenatal risk. Hypotheses were (1) genetic risk for ADHD would be related to inattentive ADHD symptoms in adolescence and mediated by childhood effortful control; (2) prenatal smoking would be related to hyperactive-impulsive ADHD symptoms during childhood and mediated by childhood surgency; and (3) there would be age-related variation, such that mediation of genetic risk would be larger for older than younger ages, whereas mediation of prenatal risk would be larger in earlier childhood than at later ages. Participants were 849 children drawn from the Oregon ADHD-1000 Cohort, which used a case control sample and an accelerated longitudinal design to track development from childhood (at year 1 ages 7-13) through adolescence (at year 6 ages 13-19). Results showed the mediational pathway from prenatal smoking through surgency to hyperactivity-impulsivity at Year 1 was significant (indirect effect estimate = .053, p < .01). The mediational pathway from polygenic risk through effortful control to inattention at Year 6 was also significant (indirect effect estimate = .084, p < .01). Both results were independent of the association between inattention and hyperactivity-impulsivity and control for the alternative etiological input and held across parent- and teacher-report of ADHD symptoms. In line with dual pathway models of ADHD, early prenatal risk for hyperactivity-impulsivity appears to operate through surgency, while polygenic genetic risk for inattention appears mediated by effortful control.

2D:4D ratios as an indicator of intrauterine androgen exposure in children who stutter

AIM

We aimed to explore whether there is a relationship between stuttering and digit ratio (2D:4D), which is thought to be a marker of prenatal testosterone exposure.

METHODS

We evaluated a total of 90 children who stutter (CWS; n = 40 mild-to-moderate and n = 50 severe stutters) and 40 healthy peers (CWNS) as controls. We used the Clinical Global Impression-Severity (CGIS) scale to measure the severity of stuttering. We measured the lengths of index finger (2D) and ring finger (4D) of both hands directly and divided to calculate 2D:4D ratio. The difference between the right and the left hand 2D:4D ratio (D_R-L) was also calculated.

RESULT

Significant difference was found in right 2D:4D and the mean D_R-L between the CWS and CWNS groups. Right 2D:4D was significantly lower in stuttering boys than in control boys, and in stuttering girls than control girls. Also, D_R-L was significantly lower in stuttering boys than control boys. In ANOVA, there were significant differences between the mild-to-moderate, severe stuttering and control groups in terms of right 2D:4D and D_R-L. Right hand 2D:4D and D_R-L decreased from controls to severe stutterers.

CONCLUSION

Our results suggest that lower right 2D:4D and D_R-L were related to the presence and severity of stuttering in children, i.e. CWS had lower 2D:4D and D_R-L than CWNS. Further large-scale prospective studies are needed to clarify the reliability of 2D:4D ratio as an indicator of fetal sex hormone exposure level and its relation with the presence and severity of stuttering in children.

Differences in serum steroid hormones concentrations in Spontaneously Hypertensive Rats (SHR) - an animal model of Attention-Deficit/Hyperactivity Disorder (ADHD)

Spontaneously hypertensive rats are the most common animal model used to study attention deficit hyperactivity disorder (ADHD). The present study investigated the levels of steroid hormones in the bloodstream of hypertensive rats and its normotensive control strain, Wistar-Kyoto rats, to check if there are any hormonal differences between both strains at the onset of ADHD. Plasma samples were collected from young (5-week-old) and mature (10-week-old) male hypertensive and normotensive rats to determine the serum level of testosterone, 17beta-estradiol, free estriol, progesterone, corticosterone and cortisol using ELISA kits. The results showed statistically significant increases in serum levels of testosterone and free estriol in 10-week-old hypertensive and normotensive rats when compared to 5-week-old animals. Moreover, the concentrations of progesterone, corticosterone and cortisol were significantly elevated in 10-week-old hypertensive rats when compared to 5-week-old animals of both strains as well as 10-week-old normotensive rats. Hormonal differences observed between 10-week-old hypertensive and normotensive rats were also accompanied by differences in the volumes of lateral ventricles as well as the third ventricle and cerebral aqueduct. In conclusion, elevated contents of progesterone, corticosterone and cortisol in hypertensive rats may be associated not only with ADHD but also with developing hypertension. This question needs further study.

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.

Behavioural and emotional disorders in childhood: A brief overview for paediatricians

Mental health problems in children and adolescents include several types of emotional and behavioural disorders, including disruptive, depression, anxiety and pervasive developmental (autism) disorders, characterized as either internalizing or externalizing problems. Disruptive behavioural problems such as temper tantrums, attention deficit hyperactivity disorder, oppositional, defiant or conduct disorders are the commonest behavioural problems in preschool and school age children. The routine Paediatric clinic or Family Medicine/General Practitioner surgery presents with several desirable characteristics that make them ideal for providing effective mental health services to children and adolescents. DSM-5 and ICD-10 are the universally accepted standard criteria for the classification of mental and behaviour disorders in childhood and adults. The age and gender prevalence estimation of various childhood behavioural disorders are variable and difficult to compare worldwide. A review of relevant published literature was conducted, including published meta-analyses and national guidelines. We searched for articles indexed by Ovid, PubMed, PubMed Medical Central, CINAHL, EMBASE, Database of Abstracts and Reviews, and the Cochrane Database of Systematic reviews and other online sources. The searches were conducted using a combination of search expressions including "childhood", "behaviour", "disorders" or "problems". Childhood behaviour and emotional problems with their related disorders have significant negative impacts on the individual, the family and the society. They are commonly associated with poor academic, occupational, and psychosocial functioning. It is important for all healthcare professionals, especially the Paediatricians to be aware of the range of presentation, prevention and management of the common mental health problems in children and adolescents.

Sex steroid hormones and sex hormone binding globulin levels, CYP17 MSP AI (-34T:C) and CYP19 codon 39 (Trp:Arg) variants in children with developmental stuttering

Developmental stuttering is known to be a sexually dimorphic and male-biased speech motor control disorder. In the present case-control study, we investigated the relationship between developmental stuttering and steroid hormones. Serum levels of testosterone, dihydrotestosterone (DHT), dehydroepiandrosterone (DHEA), oestradiol, progesterone, cortisol, and sex hormone binding globulin (SHBG), as well as the 2nd/4th digit ratio (2D:4D), an indicator of prenatal testosterone level, were compared between children who stutter (CWS) and children who do not stutter (CWNS). Moreover, two SNPs (CYP17 -34 T:C (MSP AI) and CYP19 T:C (Trp:Arg)) of cytochrome P450, which is involved in steroid metabolism pathways, were analysed between the groups. Our results showed significantly higher levels of testosterone, DHT, and oestradiol in CWS in comparison with CWNS. The severity of stuttering was positively correlated with the serum levels of testosterone, DHEA, and cortisol, whereas no association was seen between the stuttering and digit ratio, progesterone, or SHBG. The CYP17CC genotype was significantly associated with the disorder.

Maternal salivary testosterone in pregnancy and fetal neuromaturation

Testosterone exposure during pregnancy has been hypothesized as a mechanism for sex differences in brain and behavioral development observed in the postnatal period. The current study documents the natural history of maternal salivary testosterone from 18 weeks gestation of pregnancy to 6 months postpartum, and investigates associations with fetal heart rate, motor activity, and their integration. Findings indicate maternal salivary testosterone increases with advancing gestation though no differences by fetal sex were detected. High intra-individual stability in prenatal testosterone levels extend into the postnatal period, particularly for pregnancies with male fetuses. With respect to fetal development, by 36 weeks gestation higher maternal prenatal salivary testosterone was significantly associated with faster fetal heart rate and less optimal somatic-cardiac integration. Measurement of testosterone in saliva is a useful tool for repeated-measures studies of hormonal concomitants of pregnancy. Moreover, higher maternal testosterone levels are associated with modest interference to fetal neurobehavioral development.

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.

The development of self-regulation across early childhood

The development of early childhood self-regulation is often considered an early life marker for later life successes. Yet little longitudinal research has evaluated whether there are different trajectories of self-regulation development across children. This study investigates the development of behavioral self-regulation between the ages of 3 and 7 years, with a direct focus on possible heterogeneity in the developmental trajectories, and a set of potential indicators that distinguish unique behavioral self-regulation trajectories. Across 3 diverse samples, 1,386 children were assessed on behavioral self-regulation from preschool through first grade. Results indicated that majority of children develop self-regulation rapidly during early childhood, and that children follow 3 distinct developmental patterns of growth. These 3 trajectories were distinguishable based on timing of rapid gains, as well as child gender, early language skills, and maternal education levels. Findings highlight early developmental differences in how self-regulation unfolds, with implications for offering individualized support across children. (PsycINFO Database Record

The gestational foundation of sex differences in development and vulnerability

Despite long-standing interest in the role of sex on human development, the functional consequences of fetal sex on early development are not well-understood. Here we explore the gestational origins of sex as a moderator of development. In accordance with the focus of this special issue, we examine evidence for a sex differential in vulnerability to prenatal and perinatal risks. Exposures evaluated include those present in the external environment (e.g., lead, pesticides), those introduced by maternal behaviors (e.g., alcohol, opioid use), and those resulting from an adverse intrauterine environment (e.g., preterm birth). We also provide current knowledge on the degree to which sex differences in fetal neurobehavioral development (i.e., cardiac and motor patterns) are present prior to birth. Also considered are contemporaneous and persistent sex of fetus effects on the pregnant woman. Converging evidence confirms that infant and early childhood developmental outcomes of male fetuses exposed to prenatal and perinatal adversities are more highly impaired than those of female fetuses. In certain circumstances, male fetuses are both more frequently exposed to early adversities and more affected by them when exposed than are female fetuses. The mechanisms through which biological sex imparts vulnerability or protection on the developing nervous system are largely unknown. We consider models that implicate variation in maturation, placental functioning, and the neuroendocrine milieu as potential contributors. Many studies use sex as a control variable, some analyze and report main effects for sex, but those that report interaction terms for sex are scarce. As a result, the true scope of sex differences in vulnerability is unknown.