A meta-analytic review of gender differences in ADHD

Suicidal ideation in adult ADHD: Gender difference with a specific psychopathological profile

OBJECTIVE

To investigate suicidal ideation (SI) in patients with adult ADHD (aADHD), and its association with gender and psychopathology.

METHODS

Case-control study with 206 participants (patients = 103/healthy controls = 103; matched on gender, age, and education). SI was assessed by the Beck-I Depression-Inventory. The Conners' Adult ADHD Rating Scale (CAARS) was used to characterize the ADHD symptom-domains.

RESULTS

Compared to controls, the likelihood of SI was significantly higher in females with ADHD (odds ratio[OR] = 25.0 (95%CI:2.98-200.0); the difference was not significant in males (OR = 2.09 (95%CI:0.75-5.81). In females, "Problems with Self-Concept" scores on the CAARS showed the closest association with SI (OR = 5.60,95%CI:2.34-13.41]), while in males it was "Impulsivity" scores (OR = 3.01,95%CI:1.50-6.06).

CONCLUSION

Our findings extend previously described transdiagnostic associations of specific psychopathological risk factors to aADHD, including problems with self-concept and impulsivity, which are robustly associated with suicidality across diagnostic boundaries. In addition, they indicate that these associations exhibit pronounced gender-specificity in aADHD.

Availability of dopamine transporters and auditory P300 abnormalities in adults with attention-deficit hyperactivity disorder: preliminary results

OBJECTIVE

Previous studies have indicated that there is dopamine transporter (DAT) dysregulation and P300 abnormality in adults with attention-deficit hyperactivity disorder (ADHD); however, the correlations among the three have not been fully explored.

METHODS

A total of 11 adults (9 males and 2 females) with ADHD and 11 age-, sex-, and education-level-matched controls were recruited. We explored differences in DAT availability using single-photon emission computed tomography and P300 wave of event-related potentials between the two groups. The correlation between DAT availability and P300 performance was also examined.

RESULTS

DAT availability in the basal ganglia, caudate nucleus, and putamen was significantly lower in the ADHD group. Adults with ADHD had lower auditory P300 amplitudes at the Pz and Cz sites, as well as longer Fz latency than controls. DAT availability was negatively correlated to P300 latency at Pz and Fz.

CONCLUSIONS

Adults with ADHD had both abnormal DAT availability and P300 amplitude, suggesting that ADHD is linked to dysfunction of the central dopaminergic system and poor cognitive processes related to response selection and execution.

Does Preschool Self-Regulation Predict Later Behavior Problems in General or Specific Problem Behaviors?

Findings from prior research have consistently indicated significant associations between self-regulation and externalizing behaviors. Significant associations have also been reported between children's language skills and both externalizing behaviors and self-regulation. Few studies to date, however, have examined these relations longitudinally, simultaneously, or with respect to unique clusters of externalizing problems. The current study examined the influence of preschool self-regulation on general and specific externalizing behavior problems in early elementary school and whether these relations were independent of associations between language, self-regulation, and externalizing behaviors in a sample of 815 children (44% female). Additionally, given a general pattern of sex differences in the presentations of externalizing behavior problems, self-regulation, and language skills, sex differences for these associations were examined. Results indicated unique relations of preschool self-regulation and language with both general externalizing behavior problems and specific problems of inattention. In general, self-regulation was a stronger longitudinal correlate of externalizing behavior for boys than it was for girls, and language was a stronger longitudinal predictor of hyperactive/impulsive behavior for girls than it was for boys.

Attention-Deficit/Hyperactivity Disorder in Preschoolers: The Accuracy of a Short Screener

OBJECTIVE

Although early and accurate screening is required for the remediation of attention-deficit/hyperactivity disorder (ADHD), possible gender differences have not been extensively studied. We examined the classification accuracy of the parent and preschool teacher version of the Strengths and Difficulties Questionnaire (SDQ) hyperactivity-inattention (HI) subscale in girls and boys.

METHOD

The study was part of the Norwegian Mother and Child Cohort Study (MoBa). Parents and preschool teachers rated a total of 238 girls and 276 boys (mean age 3.5 years) with the SDQ HI subscale. Blinded to the parent and teacher ratings, interviewers classified the children by ADHD diagnoses with the Preschool Age Psychiatric Assessment Interview.

RESULTS

Areas under the curves for the parent HI subscale scores were good for both girls and boys (0.87 and 0.80, respectively). Preschool teacher classifications were fair (0.76) for girls and poor (0.62) for boys, a significant difference (p = .017). The subscale accurately identified children without ADHD at low parent scores (≤4), and fairly accurately identified ADHD at high scores (≥9), with maximum probabilities of finding true cases of 0.75 in girls and 0.55 in boys. Intermediate scores gave the best balance between sensitivity and specificity with low probabilities of correctly identifying children with ADHD.

CONCLUSION

The parental SDQ HI subscale was useful for screening for ADHD in preschool girls and boys. For preschool teachers, the subscale was useful for screening girls.

Prenatal exposure to bisphenol A and hyperactivity in children: a systematic review and meta-analysis

BACKGROUND

Attention-deficit hyperactivity disorder (ADHD) has increased in prevalence in the past decade. Studies attempting to identify a specific genetic component have not been able to account for much of the heritability of ADHD, indicating there may be gene-environment interactions underlying the disorder, including early exposure to environmental chemicals. Based on several relevant studies, we chose to examine bisphenol A (BPA) as a possible contributor to ADHD in humans. BPA is a widespread environmental chemical that has been shown to disrupt neurodevelopment in rodents and humans.

OBJECTIVES

Using the Office of Health Assessment and Translation (OHAT) framework, a systematic review and meta-analysis was designed to determine the relationship between early life exposure to BPA and hyperactivity, a key diagnostic criterion of ADHD.

DATA SOURCES

Searches of PubMed, Web of Science, and Toxline were completed for all literature to January 1, 2017.

STUDY ELIGIBILITY CRITERIA

For inclusion, the studies had to publish original data, be in the English language, include a measure of BPA exposure, and assess if BPA exposure affected hyperactive behaviors in mice, rats or humans. Exposure to BPA had to occur at <3 months of age for humans, up to postnatal day 35 for rats and up to postnatal day 40 for mice. Exposure could occur either gestationally (via maternal exposure) or directly to the offspring.

STUDY APPRAISAL AND SYNTHESIS METHODS

Studies were evaluated using the OHAT risk of bias tool. The effects in humans were assessed qualitatively. For rodents exposed to 20 μg/kg/day BPA, we evaluated the study findings in a random effects meta-analytical model.

RESULTS

A review of the literature identified 29 rodent and 3 human studies. A random effects meta-analysis showed significantly increased hyperactivity in male rodents. In humans, early BPA exposure was associated with hyperactivity in boys and girls.

LIMITATIONS, CONCLUSIONS, AND IMPLICATIONS OF KEY FINDINGS

We concluded that early life BPA exposure is a presumed human hazard for the development of hyperactivity. Possible limitations of this systematic review include deficiencies in author reporting, exclusion of some literature based on language, and insufficient similarity between human studies. SRs that result in hazard-based conclusions are the first step in assessing and mitigating risks. Given the widespread exposure of BPA and increasing diagnoses of ADHD, we recommend immediate actions to complete such risk analyses and take next steps for the protection of human health. In the meantime, precautionary measures should be taken to reduce exposure in pregnant women, infants and children. The present analysis also discusses potential mechanisms by which BPA affects hyperactivity, and the most effective avenues for future research.

SYSTEMATIC REVIEW REGISTRATION NUMBER

Not available.

Oral sensitization to whey proteins induces age- and sex-dependent behavioral abnormality and neuroinflammatory responses in a mouse model of food allergy: a potential role of mast cells

BACKGROUND

Growing evidence has strengthened the association of food allergy with neuropsychiatric symptoms such as depression, anxiety, and autism. However, underlying mechanisms by which peripheral allergic responses lead to behavioral dysfunction are yet to be determined. Allergen-activated mast cells may serve as mediators by releasing histamine and other inflammatory factors that could adversely affect brain function. We hypothesized that eliciting food allergy in experimental animals would result in behavioral changes accompanied by mast cell accumulation in the brain. Our hypothesis was tested in a mouse model of milk allergy using bovine milk whey proteins (WP) as the allergen.

METHODS

Male and female C57BL/6 mice at 4 weeks (young) and 10 months (old) of age underwent 5-week WP sensitization with weekly intragastric administration of 20 mg WP and 10 μg cholera toxin as an adjuvant. Age-matched sham animals were given the vehicle containing only the adjuvant. All animals were orally challenged with 50 mg WP in week 6 and their intrinsic digging behavior was assessed the next day. Animals were sacrificed 3 days after the challenge, and WP-specific serum IgE, intestinal and brain mast cells, glial activation, and epigenetic DNA modification in the brain were examined.

RESULTS

WP-sensitized males showed significantly less digging activity than the sham males in both age groups while no apparent difference was observed in females. Mast cells and their activities were evident in the intestines in an age- and sex-dependent manner. Brain mast cells were predominantly located in the region between the lateral midbrain and medial hippocampus, and their number increased in the WP-sensitized young, but not old, male brains. Noticeable differences in for 5-hydroxymethylcytosine immunoreactivity were observed in WP mice of both age groups in the amygdala, suggesting epigenetic regulation. Increased microglial Iba1 immunoreactivity and perivascular astrocytes hypertrophy were also observed in the WP-sensitized old male mice.

CONCLUSIONS

Our results demonstrated that food allergy induced behavioral abnormality, increases in the number of mast cells, epigenetic DNA modification in the brain, microgliosis, and astrocyte hypertrophy in a sex- and age-dependent manner, providing a potential mechanism by which peripheral allergic responses evoke behavioral dysfunction.

What Predicts a Good Adolescent to Adult Transition in ADHD? The Role of Self-Reported Resilience

OBJECTIVE

ADHD is a disorder associated with impairment and comorbid psychiatric problems in young adulthood; therefore, factors that may imply a more favorable outcome among adolescents with ADHD are of interest.

METHOD

This study used a longitudinal design to assess whether adolescent personal resilience characteristics during adolescence protected against psychosocial impairment, depression, and anxiety 3 years later. Self-reported protective factors were used as baseline measures in the assessment of 190 clinically referred adolescents with ADHD. A semi-structured diagnostic interview was performed at the follow-up.

RESULTS

In a group of youth with ADHD, personal resilience characteristics were associated with better psychosocial functioning in young adulthood, and less depression and anxiety.

CONCLUSION

Although further research is needed, these results indicate that personal resilience characteristics may be protective factors in the transitional period from adolescence to early adulthood.

Moderators Influencing the Effectiveness of a Behavioral Teacher Program

Objective: This study assessed which moderators influenced the effectiveness of a low-intensive behavioral teacher program for children with symptoms of Attention-Deficit/Hyperactivity Disorder (ADHD).

Methods: Primary school children (N = 114) with ADHD symptoms in the classroom were randomly assigned to the intervention program (n = 58; 91% male) or control group (n = 56; 77% male). Multilevel regression analyses assessed differential treatment gains of the intervention program in terms of ADHD symptoms and social skills. Moderators included demographic characteristics (gender, age, parental educational level), severity and comorbidity of problem behavior (ADHD symptoms, conduct and internalizing problems), social functioning, and classroom variables (teaching experience, class size).

Results: Results revealed larger program effects for older children and children from highly educated families and smaller beneficial effects for children with comorbid conduct or anxiety problems.

Conclusion: The intervention program seems more beneficial for highly educated families and children without comorbid problem behavior, but more intensive treatments appear necessary for children facing additional challenges.

ClinicalTrials.gov registration number: NCT02518711

Cognitive-behavioural interventions for attention deficit hyperactivity disorder (ADHD) in adults

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) is a developmental condition characterised by symptoms of inattention, hyperactivity and impulsivity, along with deficits in executive function, emotional regulation and motivation. The persistence of ADHD in adulthood is a serious clinical problem.ADHD significantly affects social interactions, study and employment performance.Previous studies suggest that cognitive-behavioural therapy (CBT) could be effective in treating adults with ADHD, especially when combined with pharmacological treatment. CBT aims to change the thoughts and behaviours that reinforce harmful effects of the disorder by teaching people techniques to control the core symptoms. CBT also aims to help people cope with emotions, such as anxiety and depression, and to improve self-esteem.

OBJECTIVES

To assess the effects of cognitive-behavioural-based therapy for ADHD in adults.

SEARCH METHODS

In June 2017, we searched CENTRAL, MEDLINE, Embase, seven other databases and three trials registries. We also checked reference lists, handsearched congress abstracts, and contacted experts and researchers in the field.

SELECTION CRITERIA

Randomised controlled trials (RCTs) evaluating any form of CBT for adults with ADHD, either as a monotherapy or in conjunction with another treatment, versus one of the following: unspecific control conditions (comprising supportive psychotherapies, no treatment or waiting list) or other specific interventions.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures suggested by Cochrane.

MAIN RESULTS

We included 14 RCTs (700 participants), 13 of which were conducted in the northern hemisphere and 1 in Australia.Primary outcomes: ADHD symptomsCBT versus unspecific control conditions (supportive psychotherapies, waiting list or no treatment)- CBT versus supportive psychotherapies: CBT was more effective than supportive therapy for improving clinician-reported ADHD symptoms (1 study, 81 participants; low-quality evidence) but not for self-reported ADHD symptoms (SMD -0.16, 95% CI -0.52 to 0.19; 2 studies, 122 participants; low-quality evidence; small effect size).- CBT versus waiting list: CBT led to a larger benefit in clinician-reported ADHD symptoms (SMD -1.22, 95% CI -2.03 to -0.41; 2 studies, 126 participants; very low-quality evidence; large effect size). We also found significant differences in favour of CBT for self-reported ADHD symptoms (SMD -0.84, 95% CI -1.18 to -0.50; 5 studies, 251 participants; moderate-quality evidence; large effect size).CBT plus pharmacotherapy versus pharmacotherapy alone: CBT with pharmacotherapy was more effective than pharmacotherapy alone for clinician-reported core symptoms (SMD -0.80, 95% CI -1.31 to -0.30; 2 studies, 65 participants; very low-quality evidence; large effect size), self-reported core symptoms (MD -7.42 points, 95% CI -11.63 points to -3.22 points; 2 studies, 66 participants low-quality evidence) and self-reported inattention (1 study, 35 participants).CBT versus other interventions that included therapeutic ingredients specifically targeted to ADHD: we found a significant difference in favour of CBT for clinician-reported ADHD symptoms (SMD -0.58, 95% CI -0.98 to -0.17; 2 studies, 97 participants; low-quality evidence; moderate effect size) and for self-reported ADHD symptom severity (SMD -0.44, 95% CI -0.88 to -0.01; 4 studies, 156 participants; low-quality evidence; small effect size).Secondary outcomesCBT versus unspecific control conditions: we found differences in favour of CBT compared with waiting-list control for self-reported depression (SMD -0.36, 95% CI -0.60 to -0.11; 5 studies, 258 participants; small effect size) and for self-reported anxiety (SMD -0.45, 95% CI -0.71 to -0.19; 4 studies, 239 participants; small effect size). We also observed differences in favour of CBT for self-reported state anger (1 study, 43 participants) and self-reported self-esteem (1 study 43 participants) compared to waiting list. We found no differences between CBT and supportive therapy (1 study, 81 participants) for self-rated depression, clinician-rated anxiety or self-rated self-esteem. Additionally, there were no differences between CBT and the waiting list for self-reported trait anger (1 study, 43 participants) or self-reported quality of life (SMD 0.21, 95% CI -0.29 to 0.71; 2 studies, 64 participants; small effect size).CBT plus pharmacotherapy versus pharmacotherapy alone: we found differences in favour of CBT plus pharmacotherapy for the Clinical Global Impression score (MD -0.75 points, 95% CI -1.21 points to -0.30 points; 2 studies, 65 participants), self-reported depression (MD -6.09 points, 95% CI -9.55 points to -2.63 points; 2 studies, 66 participants) and self-reported anxiety (SMD -0.58, 95% CI -1.08 to -0.08; 2 studies, 66 participants; moderate effect size). We also observed differences favouring CBT plus pharmacotherapy (1 study, 31 participants) for clinician-reported depression and clinician-reported anxiety.CBT versus other specific interventions: we found no differences for any of the secondary outcomes, such as self-reported depression and anxiety, and findings on self-reported quality of life varied across different studies.

AUTHORS' CONCLUSIONS

There is low-quality evidence that cognitive-behavioural-based treatments may be beneficial for treating adults with ADHD in the short term. Reductions in core symptoms of ADHD were fairly consistent across the different comparisons: in CBT plus pharmacotherapy versus pharmacotherapy alone and in CBT versus waiting list. There is low-quality evidence that CBT may also improve common secondary disturbances in adults with ADHD, such as depression and anxiety. However, the paucity of long-term follow-up data, the heterogeneous nature of the measured outcomes, and the limited geographical location (northern hemisphere and Australia) limit the generalisability of the results. None of the included studies reported severe adverse events, but five participants receiving different modalities of CBT described some type of adverse event, such as distress and anxiety.

Differential Behavioral and Biochemical Responses to Caffeine in Male and Female Rats from a Validated Model of Attention Deficit and Hyperactivity Disorder

Epidemiological studies suggest sex differences in attention deficit and hyperactivity disorder (ADHD) symptomatology. The potential benefits of caffeine have been reported in the management of ADHD, but its effects were not properly addressed with respect to sex differences. The present study examined the effects of caffeine (0.3 g/L) administered since childhood in the behavior and brain-derived neurotrophic factor (BDNF) and its related proteins in both sexes of a rat model of ADHD (spontaneously hypertensive rats-SHR). Hyperlocomotion, recognition, and spatial memory disturbances were observed in adolescent SHR rats from both sexes. However, females showed lack of habituation and worsened spatial memory. Although caffeine was effective against recognition memory impairment in both sexes, spatial memory was recovered only in female SHR rats. Besides, female SHR rats showed exacerbated hyperlocomotion after caffeine treatment. SHR rats from both sexes presented increases in the BDNF, truncated and phospho-TrkB receptors and also phospho-CREB levels in the hippocampus. Caffeine normalized BDNF in males and truncated TrkB receptor at both sexes. These findings provide insight into the potential of caffeine against fully cognitive impairment displayed by females in the ADHD model. Besides, our data revealed that caffeine intake since childhood attenuated behavioral alterations in the ADHD model associated with changes in BDNF and TrkB receptors in the hippocampus.

The impact of comorbid mental health symptoms and sex on sleep functioning in children with ADHD

Children with attention-deficit/hyperactivity disorder (ADHD) display more sleep problems than their peers, but it remains unclear whether comorbid mental health symptoms [i.e., anxiety, depression, oppositional-defiant disorder (ODD)] are uniquely related to sleep functioning. It is also largely unknown whether boys and girls with ADHD differ in their sleep functioning. This study (1) examined whether boys or girls with ADHD differ in their sleep functioning, (2) evaluated comorbid symptoms as uniquely related to sleep functioning domains, and (3) explored whether sex moderated associations between comorbid symptoms and sleep. Participants were 181 children (ages 7-13; 69% male; 82% White) diagnosed with ADHD. Parents completed measures assessing their child's ADHD symptoms, comorbid symptoms, and sleep functioning. Girls had poorer sleep functioning than boys across most sleep functioning domains. Sixty percent of children met cutoff criteria for having sleep problems, though rates differed significantly between girls (75%) and boys (53%). No differences in rates of sleep problems were found between ADHD subtypes/presentations or between younger and older children. In path models including ADHD and comorbid symptom dimensions, anxiety symptoms were uniquely associated with increased bedtime resistance and sleep anxiety, ADHD hyperactive-impulsive symptoms were associated with more night wakings and more parasomnia behaviors, and ODD and depressive symptoms were associated with shorter sleep duration. Depression was also uniquely associated with increased daytime sleepiness and overall sleep problems. Sex did not moderate associations between comorbid symptoms and sleep problems. This study provides important preliminary evidence that girls with ADHD experience more sleep problems than boys with ADHD. Findings also demonstrate that the associations between comorbid symptoms and sleep functioning in children with ADHD vary based on both the specific symptoms and sleep domains examined.

Associations Among Infant Iron Deficiency, Childhood Emotion and Attention Regulation, and Adolescent Problem Behaviors

This study examined whether iron deficiency (ID) in infancy contributes to problem behaviors in adolescence through its influence on poor regulatory abilities in childhood. Chilean infants (N = 1,116) were studied when there was no national program for iron fortification (1991-1996), resulting in high rates of ID (28%) and iron-deficiency anemia (IDA, 17%). Infants (54% male) were studied at childhood (Mage  = 10 years) and adolescence (Mage  = 14 years). IDA in infancy was related to excessive alcohol use and risky sexual behavior in adolescence through its effect on poor emotion regulation in childhood. Attentional control deficits at age 10 were also related to both infant IDA and heightened risk taking in adolescence. Findings elucidate how poor childhood regulatory abilities associated with infant IDA compromise adjustment in adolescence.

Overdiagnosis of ADHD in boys: Stereotype impact on neuropsychological assessment

There is vigorous debate regarding the possibility that ADHD is overdiagnosed in boys. We investigated the impact of the gender stereotype depicting boys as inattentive and impulsive on neuropsychological assessment (observation of psychology students and child's cognitive performance). In experiment 1, after the stereotype was activated, psychology students rated a "boy," a "girl," or a "child" on a behavioral assessment scale. In experiment 2, 103 children (boys and girls) completed neuropsychological tasks under stereotype threat or neutral conditions. The gender stereotype led psychology students to assess a child's behaviors more negatively if they thought the child was a boy. Boys' performance on one cognitive score declined following stereotype threat. Regression path analyses suggested moderation by stigma consciousness. Additionally, there were mediating and suppressing (through stereotype endorsement) effects. Our results suggest that the gender stereotype might contribute to the overdiagnosis of ADHD in boys.

Weekly Calendar Planning Activity for University Students: Comparison of Individuals With and Without ADHD by Gender

OBJECTIVE

To introduce a revised version of the Weekly Calendar Planning Activity (WCPA) adapted for university students (Weekly Calendar Performance Activity for students [WCPA-S]) and compare the performance of this activity between students with and without ADHD and across gender groups.

METHOD

Participants included a total of 157 students, ages 20 to 30, enrolled in universities/colleges and divided into two groups: students with ADHD (male = 23, female = 38) and without ADHD (male = 33, female = 63). A two-way ANOVA was used for data analyses. The WCPA-S was administered to each student individually.

RESULTS

Significant differences were found between students with and without ADHD and across genders in performance, duration of performance, and in the number of strategies used.

CONCLUSION

The WCPA-S proved to be an effective performance-based diagnostic tool for the utilization of executive functions in the daily life of university students. This instrument can be used to predict success in higher education and to support learning among university students with ADHD.

Complexity Analysis of Resting-State fMRI in Adult Patients with Attention Deficit Hyperactivity Disorder: Brain Entropy

Objective

Complexity analysis of functional brain structure data represents a new multidisciplinary approach to examining complex, living structures. I aimed to construct a connectivity map of visual brain activities using resting-state functional magnetic resonance imaging (fMRI) data and to characterize the level of complexity of functional brain activity using these connectivity data.

Methods

A total of 25 healthy controls and 20 patients with attention deficit hyperactivity disorder (ADHD) participated. fMRI preprocessing analysis was performed that included head motion correction, temporal filtering, and spatial smoothing process. Brain entropy (BEN) was calculated using the Shannon entropy equation.

Results

My findings demonstrated that patients exhibited reduced brain complexity in visual brain areas compared to controls. The mean entropy value of the ADHD group was 0.56 ± 0.14, compared to 0.64 ± 0.11 in the control group.

Conclusion

My study adds an important novel result to the growing literature pertaining to abnormal visual processing in ADHD that my ADHD patients had lower BEN values, indicating more-regular functional brain structure and abnormal visual information processing.

Prevalence of Attention Deficit Hyperactivity Disorder in Detention Settings: A Systematic Review and Meta-Analysis

Background: Previous studies have reported a high prevalence of attention deficit hyperactivity disorder (ADHD) among people living in detention (PLD) corresponding to a five- to ten-fold increase compared to the general population. Our main study objective was to provide an updated ADHD prevalence rate for PLD, including PLD in psychiatric units. Sub-objectives included (i) comparing different ways of assessing ADHD, including DSM-5 criteria and (ii) identifying which types of PLD are more likely to have ADHD. Methods: We conducted a systematic review and meta-analysis following the PRISMA guidelines and the MOOSE checklist. PubMed/Medline, PsycINFO, and Web of Sciences were searched combining "ADHD" and "prison" keywords and synonyms for articles published between January 1, 1966 and January 2, 2018. Potential sources of variation to the meta-analytic ADHD prevalence rate were investigated using meta-regressions and subgroups analyses. Results: The meta-analysis pooled 102 original studies including 69,997 participants. The adult ADHD prevalence rate was 26.2% (95% confidence interval: 22.7-29.6). Retrospective assessments of ADHD in childhood were associated with an increased prevalence estimate (41.1, 95% confidence interval: 34.9-47.2, p < 0.001). There was no significant difference in the prevalence estimate between screenings and clinical interviews in adulthood. Only three studies used the DSM-5 definition of ADHD and results were non-significantly different with other DSM versions. We found no difference according to participants' characteristics. Conclusion: Our results confirmed the high prevalence rate of ADHD among PLD, corresponding to a five-fold increase compared to the general population. In light of such high ADHD prevalence, our results reinforce the importance of addressing this critical public health issue by (i) systematically offering ADHD screening and diagnosis to all individuals entering detention, and (ii) delivering treatment, monitoring, and care for ADHD during and after detention. These strategies may help reduce recidivism and reincarceration, as well as violence in detention settings, in addition to improving the health and wellbeing of people living in detention. Additionally, our study suggests that using screening scales may be a reliable way of assessing ADHD, although caution is needed because a complete evaluation by an experienced clinician is required to provide a formal diagnosis.

An open resource for transdiagnostic research in pediatric mental health and learning disorders

Technological and methodological innovations are equipping researchers with unprecedented capabilities for detecting and characterizing pathologic processes in the developing human brain. As a result, ambitions to achieve clinically useful tools to assist in the diagnosis and management of mental health and learning disorders are gaining momentum. To this end, it is critical to accrue large-scale multimodal datasets that capture a broad range of commonly encountered clinical psychopathology. The Child Mind Institute has launched the Healthy Brain Network (HBN), an ongoing initiative focused on creating and sharing a biobank of data from 10,000 New York area participants (ages 5–21). The HBN Biobank houses data about psychiatric, behavioral, cognitive, and lifestyle phenotypes, as well as multimodal brain imaging (resting and naturalistic viewing fMRI, diffusion MRI, morphometric MRI), electroencephalography, eye-tracking, voice and video recordings, genetics and actigraphy. Here, we present the rationale, design and implementation of HBN protocols. We describe the first data release (n=664) and the potential of the biobank to advance related areas (e.g., biophysical modeling, voice analysis).

Attention Deficit Hyperactivity Disorder (ADHD): Controversy, Developmental Mechanisms, and Multiple Levels of Analysis

Controversy abounds regarding the symptom dimensions of attention problems, impulsivity, and hyperactivity, developmentally extreme and impairing levels of which compose the diagnostic category of attention deficit hyperactivity disorder (ADHD). I highlight causal factors, underlying mechanisms, developmental trajectories, and female manifestations of ADHD, integrating the psychobiological underpinnings of this syndrome with contextual factors related to its clinical presentation, impairments, and soaring increases in diagnosed prevalence. Indeed, despite strong heritability, ADHD is expressed via transactional patterns of influence linked to family-, school-, peer-, neighborhood-, and policy-related factors. Moreover, intervention strategies must take into account both pharmacologic and behavioral modalities if the goal is to enhance competencies, rather than symptom reduction per se. A comprehensive understanding of ADHD mandates multiple levels of analysis-spanning genes, neurotransmission, brain pathways, individual skill levels, family socialization, peer relationships, and educational and cultural forces-which must be integrated and synthesized to surpass reductionist accounts, reduce stigma, and maximize the impact of prevention- and intervention-related efforts.

Symptom covariance accounts for behavioral approach associations across impulse control disorders

Behavioral approach system (BAS) dysfunction has been identified as a correlate of and a potential mechanism for attention-deficit/hyperactivity disorder (ADHD) and comorbid disorders. This study examined the role of symptom covariation in the relations among BAS dysfunction, ADHD symptoms, and comorbid impulsive personality disorder features. Undergraduates (N = 207) completed measures of BAS functioning, ADHD symptoms, and borderline and antisocial personality disorder symptoms, and associated features (i.e., relational aggression). Hierarchical regression suggested that age, impulsive ADHD symptoms, and relational aggression were associated with BAS functioning. Adding other ADHD symptom dimensions (inattention, hyperactivity) and antisocial and borderline scores to the model did not increase variance accounted for beyond that accounted for by ADHD impulsivity scores. Results highlight a role of symptom covariance in the previously demonstrated relation between BAS, impulsive presentations of ADHD, and comorbid impulsive personality pathology. Implications for etiological models of ADHD and its co-occurrence with other disorders are discussed.

A multilevel longitudinal study of obsessive compulsive symptoms in adolescence: male gender and emotional stability as protective factors

The severity of obsessive compulsive symptoms (OCS) is suggested to be normally distributed in the general population, and they appear to have an impact on a range of aspects of adolescent development. Importantly, there are individual differences regarding susceptibility to OCS. In the present repeated measures study, OCS were studied in relation to gender and emotional stability (as a personality trait) using a normative sample of 515 adolescents at ages 16 and 18 years. OCS were assessed with the relevant subscale of the SCL-90-R and emotional stability with the Five Factor Questionnaire. A three-level hierarchical linear model was calculated to longitudinally assess the over time variations of OCS and their over time links to gender and emotional stability, while controlling for random effects due to the nesting of the data. Experiencing OCS increased with age (between 16 and 18 years). Additionally, male gender and higher emotional stability were associated with lower OCS at 16 years and these remained stable over time. Results indicate age-related and between individual differences on reported OCS that need to be considered for prevention and intervention planning.

Testing Measurement Invariance across Groups of Children with and without Attention-Deficit/ Hyperactivity Disorder: Applications for Word Recognition and Spelling Tasks

Although studies have consistently demonstrated that children with attention-deficit/hyperactivity disorder (ADHD) perform significantly lower than controls on word recognition and spelling tests, such studies rely on the assumption that those groups are comparable in these measures. This study investigates comparability of word recognition and spelling tests based on diagnostic status for ADHD through measurement invariance methods. The participants (n = 1,935; 47% female; 11% ADHD) were children aged 6–15 with normal IQ (≥70). Measurement invariance was investigated through Confirmatory Factor Analysis and Multiple Indicators Multiple Causes models. Measurement invariance was attested in both methods, demonstrating the direct comparability of the groups. Children with ADHD were 0.51 SD lower in word recognition and 0.33 SD lower in spelling tests than controls. Results suggest that differences in performance on word recognition and spelling tests are related to true mean differences based on ADHD diagnostic status. Implications for clinical practice and research are discussed.

Sex differences in stress regulation of arousal and cognition

There are sex differences in the prevalence and presentation of many psychiatric disorders. For example, posttraumatic stress disorder (PTSD) and major depression are more common in women than men, and women with these disorders present with more hyperarousal symptoms than men. In contrast, attention deficit hyperactivity disorder (ADHD) and schizophrenia are more common in men than women, and men with these disorders have increased cognitive deficits compared to women. A shared feature of the aforementioned psychiatric disorders is the contribution of stressful events to their onset and/or severity. Here we propose that sex differences in stress responses bias females towards hyperarousal and males towards cognitive deficits. Evidence from clinical and preclinical studies is detailed. We also describe underlying neurobiological mechanisms. For example, sex differences in stress receptor signaling and trafficking in the locus coeruleus-arousal center are detailed. In learning circuits, evidence for sex differences in dendritic morphology is provided. Finally, we describe how evaluating sex-specific mechanisms for responding to stress in female and male rodents can lead to better treatments for stress-related psychiatric disorders.

How Persistent is ADHD into Adulthood? Informant Report and Diagnostic Thresholds in a Female Sample

The persistence of attention-deficit/hyperactivity disorder (ADHD) into adulthood, particularly in women, is an unresolved question. Using a diverse, prospectively followed female sample (ADHD: n = 140; comparison: n = 88), we examined (a) informant (parent- vs. self-report) and (b) symptom threshold (DSM-IV cutoffs vs. a developmentally referenced criterion [DRC]) with respect to estimates of ADHD persistence into young adulthood (M = 19.6 years). We also ascertained the linkages of ADHD status (as measured by each informant and via the different symptom cutoffs) with impairment in key outcome domains. Informant diagnostic concordance was significant but small (κ = 0.22). Via parent report, more childhood-ascertained probands (44 %) than comparison participants (1 %) met full ADHD criteria in adulthood (p < 0.001, ϕ = 0.47); parallel results were found via self-report (22 % vs. 2 %; p < 0.001, ϕ = 0.28). As expected, DRC designations yielded higher persistence estimates than DSM cutoffs. With control of key covariates, parent-reported ADHD was independently associated with poor outcomes on eight of nine measures but self-reported ADHD was associated only with low math scores. Also, participants who met the DRC cutoff but not the higher DSM threshold showed similar impairment to DSM-diagnosed participants, far greater than that of participants who met neither cutoff. A lowered symptom threshold in adulthood compared to childhood appears justified.

Adult ADHD and comorbid disorders: clinical implications of a dimensional approach

Attention-deficit/hyperactivity disorder (ADHD) in the adult population is frequently associated with comorbid psychiatric diseases that complicate its recognition, diagnosis and management.The prevalence of ADHD in the general adult population is 2.5% and it is associated with substantial personal and individual burden. The most frequent comorbid psychopathologies include mood and anxiety disorders, substance use disorders, and personality disorders. There are strong familial links and neurobiological similarities between ADHD and the various associated psychiatric comorbidities. The overlapping symptoms between ADHD and comorbid psychopathologies represent challenges for diagnosis and treatment. Guidelines recommend that when ADHD coexists with other psychopathologies in adults, the most impairing condition should generally be treated first.Early recognition and treatment of ADHD and its comorbidities has the potential to change the trajectory of psychiatric morbidity later in life. The use of validated assessment scales and high-yield clinical questions can help identify adults with ADHD who could potentially benefit from evidence-based management strategies.

In vivo and in vitro sex differences in the dendritic morphology of developing murine hippocampal and cortical neurons

Altered dendritic morphology is common in neurodevelopmental disorders (NDDs), many of which show sex biases in prevalence, onset and/or severity. However, whether dendritic morphology varies as a function of sex in juvenile mice or primary neuronal cell cultures is largely unknown even though both are widely used models for studying NDDs. To address this gap, we quantified dendritic morphology in CA1 pyramidal hippocampal and adjacent somatosensory pyramidal cortical neurons from male and female postnatal day (P)28 C57BL/6J mice. As determined by Sholl analysis of Golgi-stained brain sections, dendritic arbors of male hippocampal neurons are more complex than females. Conversely, dendritic morphology of female cortical neurons is more complex than males. In primary neuron-glia co-cultures from P0 mouse hippocampi, male neurons have more complex dendritic arbors than female neurons. Sex differences are less pronounced in cortical cultures. In vitro sex differences in dendritic morphology are driven in part by estrogen-dependent mechanisms, as evidenced by decreased dendritic complexity in male hippocampal neurons cultured in phenol red-free media or in the presence of an estrogen receptor antagonist. Evidence that sex influences dendritic morphogenesis in two models of neurodevelopment in a region-specific manner has significant mechanistic implications regarding sex biases in NDDs.

Motor Vehicle Crash Risk Among Adolescents and Young Adults With Attention-Deficit/Hyperactivity Disorder

Importance

Attention-deficit/hyperactivity disorder (ADHD) often persists into adolescence, when motor vehicle crash risk peaks. We know little about when adolescents with ADHD get licensed and, once they do, the extent to which they have increased crash risk compared with adolescents without ADHD.

Objectives

To examine the association between ADHD and both driver licensing and crash involvement and whether it varies by sex, licensing age, and/or being prescribed ADHD medication at licensure.

Design, Setting, and Participants

This retrospective cohort study was conducted at 6 primary care practices of the Children's Hospital of Philadelphia, a large pediatric health care network in southeastern Pennsylvania and southern New Jersey. Using electronic health records, we defined a cohort of 2479 adolescents and young adults with ADHD and 15 865 without ADHD who were (1) born from 1987 to 1997; (2) residents of New Jersey and patients at 1 of 6 New Jersey primary care practices at age 12 years or older; and (3) age-eligible to obtain a driver's license from 2004 through 2014. Electronic health records data were then linked with New Jersey's statewide driver licensing and crash databases for 2004 through 2014.

Main Outcomes and Measures

Acquisition of a driver's license and first involvement as a driver in a police-reported crash. Survival analysis was used to estimate adjusted hazard ratios for licensing and crash outcomes through age 25 years.

Results

The median age of individuals at the end of the study was 22.2 years (interquartile range, 19.7-24.8). Compared with individuals without ADHD, the licensing probability of individuals with ADHD 6 months after eligibility was 35% lower (for males: adjusted hazard ratio, 0.65; 95% CI, 0.61-0.70; females: adjusted hazard ratio, 0.64; 95% CI, 0.58-0.70). Among individuals with a driver's license, 764 of 1785 with ADHD (42.8%) and 4715 of 13 221 without ADHD (35.7%) crashed during the study period. The adjusted risk for first crash among licensed drivers with ADHD was 1.36 times higher than for those without ADHD (95% CI, 1.25-1.48) and did not vary by sex, licensing age, or over time. Only 129 individuals with ADHD (12.1%) were prescribed medication in the 30 days before licensure.

Conclusions and Relevance

Adolescents with ADHD get licensed less often and at an older age. Once licensed, this cohort has a greater risk of crashing. Additional research is needed to understand the specific mechanisms by which ADHD influences crash risk.

Prevalence of attention-deficit/hyperactivity and other disruptive behaviour disorder symptoms among primary school-age children in Kayseri, Turkey

Objectives This study aimed to determine the prevalence of attention-deficit/hyperactivity disorder (ADHD), oppositional defiant disorder (ODD), and conduct disorder (CD), and their influencing factors on primary school-age children. Methods This cross-sectional study was conducted among 2045 students, 7-15 years old, who were randomly selected from seven schools in Kayseri, Turkey, in 2012. Participants were stratified by socioeconomic status. Data were collected using the Turgay DSM-IV-Based Child and Adolescent Behavioural Disorders Screening and Rating Scale (T-DSM-IV-S). For statistical analyses, the t-test and analysis of variance were used. Results Rates of disruptive behaviour disorders (DBDs) among children were as follows: ADHD, 6.2%; CD, 14.4%; and ODD, 6.7%. The prevalence of ADHD was higher in boys and children whose mothers were homemakers and from poorly-educated and low-income families, compared with their peers. CD was more prevalent among boys and children 13-15 years old, whose parents had low income levels and were separated. ODD was higher in boys and children whose mothers were homemakers. Conclusions Our findings suggest that the overall prevalence of DBDs in our study area is 27.4%, which is similar to the pooled worldwide prevalence. Adverse family factors are closely associated with the prevalence of DBDs.

Co-Occurrence of ODD and CD in Preschool Children With Symptoms of ADHD

OBJECTIVE

Patterns of co-occurrence between ADHD, Oppositional Defiant Disorder (ODD), and Conduct Disorder (CD) were examined in a sample of non-referred preschool children. ADHD subtypes and sex differences were also explored.

METHOD

Children aged 3.5 years ( n = 1,048) with high scores on ADHD characteristics were recruited from the Norwegian Mother and Child Cohort Study and clinically assessed, including a semi-structured psychiatric interview.

RESULTS

In children with ADHD, concurrent ODD was present more often than CD (31% vs. 10%), but having ADHD gave higher increase in the odds of CD than of ODD (ODD: odds ratio [OR] = 6.7, 95% confidence interval [CI] = [4.2, 10.8]; CD: OR = 17.6, 95% CI = [5.9, 52.9]). We found a greater proportion of children having the combined ADHD subtype as well as more severe inattentiveness among children with co-occurring CD compared with ODD. Sex differences were minor.

CONCLUSION

There are important differences in co-occurring patterns of ODD and CD in preschool children with ADHD.

Evaluating relationships among clinical working memory assessment and inattentive and hyperactive/impulsive behaviors in a community sample of children

OBJECTIVE

This study examined relationships between inattentive and hyperactive/impulsive behaviors and working memory (WM) functioning, and the utility of WM in categorical diagnosis of ADHD versus considering ADHD symptoms on a continuum.

METHOD

The study included 50 male children (6-12 years). Inattentive and hyperactive/impulsive behaviors were measured by the Conners-3P parent report, and WM was assessed by the WISC-IV WM subtests and Working Memory Index (WMI).

RESULTS

WISC-IV Arithmetic and Digit Span Backward were most consistently related to inattentive behaviors, and no WM measure was consistently related to ADHD hyperactive/impulsive behaviors. Arithmetic and Digit Span Backward also accounted for significant variance in inattentive behaviors and ADHD inattention symptoms, respectively. Neither the WMI nor the Arithmetic subtest correctly classified individuals diagnosed with ADHD.

CONCLUSION

Measurement of inattentive behaviors on a continuum best characterized relationships between symptoms of ADHD and WM functioning; WM functioning did not have utility in categorical understanding of ADHD.

Neuroimmunology and neuroepigenetics in the establishment of sex differences in the brain

The study of sex differences in the brain is a topic of neuroscientific study that has broad reaching implications for culture, society and biomedical science. Recent research in rodent models has led to dramatic shifts in our views of the mechanisms underlying the sexual differentiation of the brain. These include the surprising discoveries of a role for immune cells and inflammatory mediators in brain masculinization and a role for epigenetic suppression in brain feminization. How and to what degree these findings will translate to human brain development will be questions of central importance in future research in this field.

Age and gender-related differences in emotional and behavioural problems and autistic features in children and adolescents with Down syndrome: a survey-based study of 674 individuals

BACKGROUND

Recent studies have indicated an increased risk of autism, behavioural and emotional problems and attention-deficit/hyperactivity disorder in individuals with Down syndrome.

METHOD

In a large-scale survey-based study, we examined the rates of these problems and their relationship to age and gender, in a sample of 674 individuals (4-18 years) with Down syndrome. The relationship with IQ level was also explored in a subsample (n = 175). The Strengths and Difficulties Questionnaire and the Social Communication Questionnaire were used to assess behavioural and emotional problems and autism traits.

RESULTS

On the Strengths and Difficulties Questionnaire, peer problems were the most frequently reported difficulty (48% > cut-off), followed by hyperactivity/inattention (34% > cut-off). On the Social Communication Questionnaire, 37% scored at or above cut-off (≥15) for autism spectrum disorder; 17% were at or above the suggested cut-off (≥22) for autism. Little association between age and behavioural or emotional problems or with severity of autistic symptomatology was found. However, peer problems were more common in adolescents than in junior school children (P < 0.001); Hyperactivity/inattention was less prevalent among adolescents (P < 0.001).

CONCLUSIONS

High rates of autistic features, emotional and behavioural problems are documented. These problems are related to age, gender and degree of intellectual disability.

Assessment of ADHD Symptoms and the Issue of Cultural Variation: Are Conners 3 Rating Scales Applicable to Children and Parents With Migration Background?

OBJECTIVE

The objective was to evaluate whether Conners 3 ( Conners 3rd edition) ratings of ADHD symptoms are robust to distortion by cultural variation when applied to children with migration background living in Germany.

METHOD

From 2010 to 2011, Conners 3 data (self-rating, parent rating, and teacher rating) of 243 children with Turkish migration background, aged 6 to 16 years, were collected in various German schools. Allocation of items to latent factors was tested with confirmatory analyses. Reliability and validity of resulting factors was calculated and influence of acculturation, gender, and age on rating-modalities was examined.

RESULTS

Confirmatory factor analyses showed high model fits for all rating-modalities. Resulting scales had good reliability and validity. There was a small influence of acculturation on parent ratings of oppositional defiant disorder but not on ADHD core symptoms.

CONCLUSION

Conners 3 ratings seem to be robust against influences of cultural variation. Their German translation can be utilized for children with Turkish migration background without limitation.

Positive alcohol expectancies mediate associations between ADHD behaviors and alcohol-related problems among college students

An increasing percentage of college students report being affected by ADHD behaviors, and this population is at increased risk of experiencing negative consequences associated with alcohol consumption. However, specific factors motivating alcohol consumption and contributing to negative outcomes among these individuals are not well understood. Recent work suggests alcohol expectancies may interact with ADHD behaviors to influence negative drinking-related outcomes among those with elevated inattention and/or hyperactivity-impulsivity. Seven-hundred-forty emerging adults (M age = 19.13 [SD = 2.25] years; 72.1% female; 85.8% Caucasian) enrolled in two public universities in the Southeast and Midwest USA completed the Brief Comprehensive Effects of Alcohol Survey (B-CEOA) and provided self-reports of ADHD symptoms and drinking-related outcomes. Multiple mediation analyses were conducted to evaluate effects of ADHD behaviors (i.e., hyperactivity-impulsivity, and inattention) and related impairment in major life domains (e.g., social interactions, occupational and educational activities, fulfillment of daily responsibilities) on drinking-related outcomes via positive and negative alcohol expectancies, controlling for sex, age, co-occurring oppositional behaviors, and data collection site. Inattention, hyperactivity-impulsivity, and impairment directly predicted both personal and social problems consequent to alcohol use. Effects of ADHD behaviors and impairment on drinking-related personal and social problems were partially mediated by positive expectancies. Findings are consistent with and extend prior work supporting a role of positive alcohol expectancies in alcohol-related negative outcomes among college students experiencing mild to moderate symptoms of ADHD.

Polymorphisms of STS gene and SULT2A1 gene and neurosteroid levels in Han Chinese boys with attention-deficit/hyperactivity disorder: an exploratory investigation

This study examined the relationships among polymorphisms of the STS gene and SULT2A1 gene, dehydroepiandrosterone (DHEA) and its sulfated form (DHEA-S), and characteristics of attention-deficit/hyperactivity disorder (ADHD). We used cheek swabs to obtain the genomic DNA of 200 ADHD male probands (mean age: 8.7 years), 192 patients’ mothers and 157 patients’ fathers. Three SNPs in the STS gene (rs6639786, rs2270112, and rs17268988) and one SNP in the SULT2A1 gene (rs182420) were genotyped. Saliva samples were collected from the ADHD patients to analyze DHEA and DHEA-S levels. The behavioral symptoms were evaluated with the Swanson, Nolan, and Pelham, and Version IV Scale for ADHD (SNAP-IV), and the neuropsychological function was assessed using the Conners’ Continuous Performance Tests (CPT). We found the C allele of rs2270112 within the STS gene to be over-transmitted in males with ADHD. Polymorphisms of rs182420 within the SULT2A1 gene were not associated with ADHD. In addition, the C allele carriers of rs2270112 demonstrated significantly higher DHEA-S levels than the G allele carriers. Levels of DHEA were positively correlated with attention as measured by the CPT. These findings support a potential role in the underlying biological pathogenesis of ADHD with regard to STS polymorphisms and neurosteroid levels.

An epidemiological study of ADHD and conduct disorder: does family conflict moderate the association?

PURPOSE

To examine the role of family conflict in the relationship between attention deficit hyperactivity disorder (ADHD) and conduct disorder (CD).

METHODS

A cross-sectional national population survey was carried out among 10,838 14-16 year old students in all secondary schools in Iceland. Three latent measures, financial status, ADHD and CD, and one observed measure, family structure, were included in the study. A structural equation model was used to evaluate direct effects between ADHD and CD for four different groups; females and males, experiencing family conflict and those not experiencing family conflict.

RESULTS

ADHD was significantly and positively associated with CD for all groups. When controlling for financial status and family structure it was found that ADHD was positively and significantly associated with CD for adolescent females and males not experiencing family conflict as well as for those experiencing family conflict. The link between ADHD and CD was significantly stronger for those adolescents who had experienced family conflict compared to those who had not experienced family conflict. These results suggest that family conflict moderates the association between ADHD and CD for both girls and boys.

CONCLUSIONS

The results of this study indicate that family environment and ADHD symptoms are important when predicting CD among adolescent youth. Most notably, family conflict exacerbates the effects of ADHD symptoms on CD among both females and males.

Methylphenidate in the treatment of an adolescent female with obsessive-compulsive disorder and attention deficit hyperactivity disorder: a case report

OBJECTIVES

We describe a case whereby a 15-year-old female with treatment-resistant obsessive-compulsive disorder (OCD) was treated with methylphenidate for co-morbid attention deficit hyperactivity disorder (ADHD). The ADHD-OCD co-morbidity has often been overlooked clinically due to conflicting opinions about their underlying neurobiology and treatment options.

CONCLUSIONS

In this adolescent with co-morbid ADHD and OCD, we observed that the adjunctive use of methylphenidate resulted in enhanced treatment response to both psychological and pharmacological interventions for OCD. This case highlights the need to identify and treat co-morbid ADHD in OCD cases where progress has stalled.

Methylphenidate use and school performance among primary school children: a descriptive study

BACKGROUND

There is no conclusive evidence that stimulants have beneficial effects on major associated outcome parameters, particularly school performance. We assessed the differences in school performance among children using methylphenidate at the end of primary school in relation to various parameters of methylphenidate use.

METHODS

We linked children from a pharmacy prescription database with standardized achievement test results at the end of primary school. We explored differences in test scores between current methylphenidate users versus never users and methylphenidate users who stopped treatment at least 6 months before the test, early versus late starters, different dosage of methylphenidate, and concurrent antipsychotic or asthma treatment.

RESULTS

Out of the 7736 children, 377 (4.9%) children were treated with methylphenidate at the time of the test. After adjusting for confounders the methylphenidate users (532.58 ± .48) performed significantly lower on the test than never users (534.72 ± .11). Compared with late starters of methylphenidate treatment (536.94 ± 1.51) we found significantly lower test scores for the early starters (532.33 ± .50).

CONCLUSION

Our study indicates that children using methylphenidate still perform less at school compared to their peers. Our study also suggests that earlier start of methylphenidate treatment is associated with a lower school performance compared to children starting later with the treatment. This result could either indicate a limited effect of long term treatment or a more strongly affected group of early starters.

Sex Differences in the Physiological and Behavioral Effects of Chronic Oral Methylphenidate Treatment in Rats

Methylphenidate (MP) is a psychostimulant prescribed for Attention Deficit Hyperactivity Disorder. Previously, we developed a dual bottle 8-h-limited-access-drinking-paradigm for oral MP treatment of rats that mimics the pharmacokinetic profile of treated patients. This study assessed sex differences in response to this treatment. Male and female Sprague Dawley rats were assigned to one of three treatment groups at 4 weeks of age (n = 12/group): Control (water), low dose (LD) MP, and high dose (HD) MP. Rats drank 4 mg/kg MP (LD) or 30 mg/kg MP (HD) during the first hour, and 10 mg/kg (LD) or 60 mg/kg MP (HD) for the remaining 7 h each day. Throughout 3 months of treatment, rats were monitored for body weight, food intake, and fluid intake; as well as tested for open field behavior, circadian activity, novel object recognition, and social interaction. Chronic MP treated rats exhibited reduced fluid intake during distinct treatment weeks to a greater extent in males, and reduced total fluid intake in males only. HD MP treatment decreased body weight in both sexes, while HD MP increased total food intake in females only, likely to offset energy deficits resulting from MP-induced hyperactivity. LD and HD MP increased locomotor activity in the open field, particularly in females and during later treatment weeks. MP dose-dependently increased activity during the dark cycle of circadian testing in females, while in males hyperactivity was only exhibited by HD rats. HD MP increased center activity to a greater extent in males, while MP increased rearing behavior in females only. MP had no effect on social behavior or novel object recognition in either sex. This study concludes that chronic oral MP treatment at clinically-relevant dosages has significant effects on food intake, body weight, open field behavior, and wake cycle activity. Particularly marked sex differences were apparent for locomotor activity, with females being significantly more sensitive to the hyperactivating effects of the drug. These findings suggest that chronic MP exposure beginning in adolescence can have significant behavioral effects that are both dose- and sex-dependent, and raise concerns regarding the reversibility of these effects post-discontinuation of treatment.

Experiences of employed women with attention deficit hyperactive disorder: A phenomenological study

BACKGROUND

Employees with attention-deficit/hyperactivity disorder (ADHD) face various risks in the workplace. Little is known of the specific challenges women with ADHD experience.

OBJECTIVE

To explore the experiences of working women with ADHD and learn the strategies and accommodations that facilitate their maintaining employment.

METHOD

Qualitative phenomenological approach was used to echo women's subjective perceptions and experiences representing their daily interactions in their workplace. In-depth interviews were conducted with eleven tertiary-educated employed women (M = 33.5; SD = 6.61 years), diagnosed with ADHD and the transcripts were analyzed by three researchers, using the qualitative phenomenological approach.

RESULTS

Most interviewed women with ADHD described interactions with their workplace as confusing, overwhelming, and chaotic. They perceived their ADHD as a significant obstacle to success in employment that also conferred some advantages. Three interview themes are explored here (1) challenges in coping with job demands and the workplace, including the disclosure dilemma; (2) personal coping strategies; (3) useful accommodations.

CONCLUSIONS

For the women interviewed, employment was important for their self-identity, beyond simply making a living. Their experiences indicate impaired executive functioning and inhibition and sensory sensitivity, consistently with theoretical models for ADHD. They identified gender-specific issues, such as using medication during pregnancy, which led them to seek for non-pharmacological coping mechanisms. They contributed practical knowledge regarding employee-led adaptations and employer-provided workplace accommodations.

Can IQ predict parent-reported behavioral and emotional problems in children with neurological deficiencies?

OBJECTIVE

The aim of the current study was to investigate whether total intelligence scores (FSIQ) and/or a discrepancy in intelligence can predict behavioral or emotional problems in children with neurological deficiencies.

METHOD

The population consists of children with neurological deficiencies (N = 610, ranging from 6 to 17 years), referred due to concerns on the (educational) development of the child to a tertiary outpatient clinic. All children were tested with the Dutch Wechsler Intelligence Scale for Children - third edition (WISC-III-NL). A VIQ-PIQ discrepancy score was calculated by subtracting the performance capacities of the verbal capacities. The effects of demographic variables, FSIQ, and the VIQ-PIQ discrepancy on two parent-rated questionnaires measuring behavior and emotions in children were analyzed with linear and logistic regression models.

RESULTS AND CONCLUSION

The VIQ-PIQ discrepancy was not predictive of behavioral or emotional problems recorded on the above-mentioned parent-rated questionnaires. The FSIQ score, age, and sex were predictive to some extent: increases in age and FSIQ led to a decrease of reported problems, and boys showed more problems than girls. Children with neurological deficiencies had on average significantly higher verbal capacities than performance capacities, in line with the neuropsychological principle that language survives brain damage whereas performance capacities are more affected.

Serotonin transporter polymorphism moderates the effects of caregiver intrusiveness on ADHD symptoms among institutionalized preschoolers

Research consistently chronicles a variety of mental health difficulties that plague institutionally reared children, including attention-deficit/hyperactivity disorder (ADHD), even if not all institutionalized children evince such problems. In seeking to extend work in this area, this research on gene × environment (GXE) interplay investigated whether the effect of the quality of institutional care-most notably, caregiver intrusiveness-on ADHD symptoms is moderated by the serotonin transporter (5-HTTLPR) polymorphism. One hundred and twenty-seven institutionalized preschoolers were evaluated using the Child Behavior Checklist. Caregiver-rated attention problems and hyperactivity were unrelated to both 5-HTTLPR polymorphism and caregiver intrusiveness. A significant GXE effect, independent of age at placement or duration of institutionalization, emerged, however, consistent with the differential-susceptibility hypothesis: s/s homozygotes manifest the most and least ADHD symptoms when they experienced, respectively, more and less intrusive caregiving. These results provide new insight into the reasons why some institutionalized children, but not others, exhibit ADHD symptoms.

Utilization of Stimulants and Atomoxetine for Attention-Deficit/Hyperactivity Disorder among 5.4 Million Children Using Population-Based Longitudinal Data

Use of stimulants to treat attention-deficit/hyperactivity disorder (ADHD) has increased over the past two decades and varies substantially between countries. The objective of this multinational population-based study was to examine utilization of ADHD drugs (stimulants and atomoxetine) including comedication with other psychotropic drugs in the entire child population in the five Nordic countries. We included longitudinal data on dispensed ADHD drugs from five Nordic prescription registers during 2008-2012, which in 2012 comprised 48,296 individuals among 5.42 million inhabitants aged 0-17 years. Prevalence of filling ≥1 prescriptions of ADHD drugs among children aged 6-17 years increased during 2008-2012 from 5.9 to 11.2 and 19.4 to 31.0 per 1000 girls and boys, respectively. Prevalence by country showed that Iceland, Finland and Sweden had a steady increase during the study period, while in Norway the prevalence was quite stable and in Denmark it levelled off from 2010. Use in preschoolers (aged 0-5 years) was rare. Iceland had much higher prevalence and incidence than the other Nordic countries. The incidence of ADHD drug use increased during the study period, from 4.0 to 4.9 and from 1.5 to 2.3 per 1000 boys and girls, respectively. The increasing number of new users levelled off somewhat after 2010. Comedication with other psychotropic drugs was more common among girls (33.9%) than boys (27.0%) and was mainly melatonin, followed by antidepressants and antipsychotics. Overall prevalence of ADHD drug use increased among Nordic girls and boys aged 6-17 years, whereas the incidence increased slightly during 2008-2010 but levelled off through 2012. The substantial differences in ADHD drug use across the Nordic countries and high degree of comedication with other psychotropic drugs underscore the importance of close monitoring of treatment for ADHD among children.

Early development of comorbidity between symptoms of attention-deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD)

Attention-deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD) are among the most common childhood disorders and frequently co-occur. The present study sought to advance our understanding of how comorbidity between ADHD and ODD develops during the preschool years by testing a cross-lagged model that integrates 2 prominent models: the developmental precursor model and the correlated risk factors model. Participants were 199 children (107 boys) who took part in a longitudinal study of preschoolers with behavior problems. Parent reports of ADHD and ODD symptoms were collected annually from ages 3 to 6 and a family history interview was administered at age 3. In support of the developmental precursors model, ADHD symptoms predicted later argumentative/defiant symptoms. In support of the correlated risk factors model, family histories of ADHD and ODD/CD symptoms were correlated risk factors that uniquely predicted ADHD and anger/irritable symptoms in children. Results suggest that the correlated risk factors model may best explain the development of comorbidity between symptoms of ADHD and anger/irritability, whereas the developmental precursors model may better explain the development of comorbidity between symptoms of ADHD and argumentative/defiance.

Cognitively and physically demanding exergaming to improve executive functions of children with attention deficit hyperactivity disorder: a randomised clinical trial

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) is one of the most common mental disorders observed in childhood and adolescence. Its key symptoms - reduced attention, poor control of impulses as well as increased motor activity - are associated with decreased executive functions performance, finally affecting academic achievement. Although drug treatments usually show some effect, alternative treatments are continually being sought, due to lack of commitment and possible side effects. Cognitive trainings are frequently used with the objectives of increasing executive function performance. However, since transfer effects are limited and novelty and diversity are frequently ignored, interventions combining physical and cognitive demands targeting a broader range of cognitive processes are demanded.

METHODS

The aim of the study is to examine the effects of a cognitively and physically demanding exergame on executive functions of children with ADHD. In a randomised clinical trial, 66 girls and boys diagnosed with ADHD (age 8-12) will be assigned either to an 8-week exergame intervention group (three training sessions per week à 30 min) or a waiting-list control group. Before and afterwards, the executive function performance (computer-based tests), the sport motor performance and ADHD symptoms will be assessed.

DISCUSSION

The current study will offer insights into the effectiveness of a combination of cognitive and physical training using exergaming. Positive effects on the executive functions, sport motor performance and ADHD symptoms are hypothesized. Beneficial effects would mean a large degree of scalability (simple and cost-effective) and high utility for patients with ADHD.

TRIAL REGISTRATION

KEK BE 393/15 (March 8, 2016); DRKS00010171 (March 14, 2016).

Temperamental predictors of developmental trajectories of inattention and hyperactivity-impulsivity problems in schoolchildren

Background

The current study aimed to examine the temperamental predictors of developmental trajectory subgroups of children's inattention and hyperactivity–impulsivity problems through a short-term longitudinal study.

Methods

Children (n = 1344) were divided into younger (age 6–8 years) and older (age 9–11 years) groups in order to observe changes in inattention and hyperactivity–impulsivity problems. Inattention and hyperactivity–impulsivity problems were measured three times at 5-month intervals and Cloninger's four temperaments (novelty seeking, harm avoidance, reward dependence, and persistence) were examined on the first occasion only. A cohort sequential design and growth mixture model were used for investigating trajectory subgroups and multiple logistic regression analysis to examine the temperamental predictors.

Results

Developmental trajectories of inattention and hyperactivity–impulsivity showed different subgroupings depending on the age group of children. Temperament (high score on novelty seeking and low score on persistence as well as high score on reward dependence) and gender predicted the likelihood of belonging to high-risk versus low-risk subgroups.

Conclusion

Suggestions taking into account the predictors of developmental trajectories in inattention and hyperactivity–impulsivity problems for future research are discussed along with the limitations of the current study.

Preschool hyperactivity specifically elevates long-term mental health risks more strongly in males than females: a prospective longitudinal study through to young adulthood

Evidence of continuities between preschool hyperactivity and adult mental health problems highlights the potential value of targeting early identification and intervention strategies. However, specific risk factors are currently unclear. This large-scale prospective longitudinal study aimed to identify which hyperactive preschoolers are at the greatest long-term risk of poor mental health. One hundred and seventy children (89 females) rated as hyperactive by their parents, and 88 non-hyperactive controls (48 females) were identified from a community sample of 4215 3-year-olds. Baseline data relating to behavioral/emotional problems and background characteristics were collected. Follow-up mental health and functional impairment outcomes were collected between 14 and 25 years of age. At age 3 years, males and females in the hyperactive group had similarly raised levels of hyperactivity and other behavior problems. In adolescence/young adulthood, these individuals showed elevated symptoms of ADHD, conduct disorder, mood disorder, anxiety and autism, as well as functional impairment. Preschool hyperactivity was strongly predictive of poor adolescent/adult outcomes for males across domains with effects being specifically driven by hyperactivity. For females, the effects of preschool hyperactivity were smaller and dropped to non-significant levels when other preschool problems were taken into account. Environmental risk factors also differed between the sexes, although these may also have been mediated by genetic risk. In conclusion, these results demonstrate marked sex differences in preschool predictors of later adolescent/adult mental health problems. Future research should include a measure of preschool inattention as well as hyperactivity. The findings highlight the potential value of tailored approaches to early identification strategies.

Trend, characteristics, and pharmacotherapy of adults diagnosed with attention-deficit/hyperactivity disorder: a nationwide survey in Taiwan

OBJECTIVE

Attention-deficit/hyperactivity disorder (ADHD) in adults may result in functional impairment warranting clinical interventions. However, few studies have investigated the diagnosis and treatment rates of adult ADHD in non-Caucasian ethnic groups. This study used nationwide population-based data to investigate the rate of diagnosis, associated characteristics, and pharmacological treatment for adult ADHD in Taiwan.

METHODS

Adults (age ≥18 years) newly diagnosed with ADHD (n=5,397) between January 2000 and December 2011 were enrolled from the National Health Insurance database in Taiwan. All patients were monitored until December 31, 2011. Patients who received treatment with immediate-release methylphenidate (IR-MPH), osmotic release oral system-methylphenidate (OROS-MPH), and atomoxetine (ATX) were analyzed.

RESULTS

The cumulative prevalence of adult ADHD was 0.028%, and the incidence increased 10.9-fold from 2000 to 2011. The male to female ratio was 1.16, and 74.9% of the patients had the inattentive type. Overall, 55% of the patients received drug therapy for ADHD, and the average treatment duration was 478.3 days. Of the total patients, 50.4%, 13.3%, and 1.7% were prescribed with IR-MPH, OROS-MPH, and ATX, for a mean duration of 453.9, 327.7, and 161.4 days, respectively.

CONCLUSION

This population-based study showed an increasing trend in the diagnosis rate of adult ADHD; however, this rate is still low compared with Western countries. Approximately 45% of the adult patients with ADHD never received medication for their ADHD. Continuous efforts are needed to increase public awareness of adult ADHD.