A meta-analytic review of gender differences in ADHD

Impact of COVID-19 pandemic on prescription stimulant use among children and youth: a population-based study

COVID-19 associated public health measures and school closures exacerbated symptoms in some children and youth with attention-deficit hyperactivity disorder (ADHD). Less well understood is how the pandemic influenced patterns of prescription stimulant use. We conducted a population-based study of stimulant dispensing to children and youth ≤ 24 years old between January 1, 2013, and June 30, 2022. We used structural break analyses to identify the pandemic month(s) when changes in the dispensing of stimulants occurred. We used interrupted time series models to quantify changes in dispensing following the structural break and compare observed and expected stimulant use. Our main outcome was the change in the monthly rate of stimulant use per 100,000 children and youth. Following an initial immediate decline of 60.1 individuals per 100,000 (95% confidence interval [CI] - 99.0 to - 21.2), the monthly rate of stimulant dispensing increased by 11.8 individuals per 100,000 (95% CI 10.0-13.6), with the greatest increases in trend observed among females, individuals in the highest income neighbourhoods, and those aged 20 to 24. Observed rates were between 3.9% (95% CI 1.7-6.2%) and 36.9% (95% CI 34.3-39.5%) higher than predicted among females from June 2020 onward and between 7.1% (95% CI 4.2-10.0%) and 50.7% (95% CI 47.0-54.4%) higher than expected among individuals aged 20-24 from May 2020 onward. Additional research is needed to ascertain the appropriateness of stimulant use and to develop strategies supporting children and youth with ADHD during future periods of long-term stressors.

Females evaluated for autism: characteristics and co-occurring and differential DSM-5 diagnoses

Objective: While sex differences in autism spectrum disorder (ASD) have been identified in areas such as neurocognitive functioning, behavior patterns, and diagnostic criteria, less work has focused on differences within females referred for ASD evaluation, including those who did not go on to receive a diagnosis. This study examined psychological and behavioral characteristics and co-occurring and differential DSM-5 diagnoses between pediatric female participants who received an ASD diagnosis (ASD+) and those who did not (ASD-). Method: Data on cognitive functioning, adaptive functioning, internalizing symptoms, externalizing symptoms, and ADOS-2 scores were analyzed among 137 3- to 20-year-old patients. The sample was divided into two age groups (ages 3-8 and ages 9-20) for analyses of between-group differences (ASD+ vs. ASD-) and predictors of group membership. Results: Females in the ASD+ group were significantly younger, had lower cognitive scores, lower internalizing and externalizing symptoms, and had higher Autism Diagnostic Observation Schedule-2 (ADOS-2) scores than those in the ASD- group. ADOS-2 scores were also the only significant predictor of ASD group membership across age groups. The ASD+ group had a higher percentage of intellectual disability while the ASD- group had higher percentages of anxiety disorder, attention-deficit/hyperactivity disorder, and disruptive behavior disorders. Conclusions: Psychological and behavioral presentations among females referred for ASD evaluation varied with age and ASD diagnostic groups. These results highlight potential female differences in ASD referrals and identification of ASD and the need to improve care for females in consideration of demographic factors.

The pooled prevalence of attention-deficit/hyperactivity disorder among children and adolescents in Ethiopia: A systematic review and meta-analysis

BACKGROUND

Attention-deficit/hyperactivity disorder is one of the most common childhood neurobehavioral disorders, which has a serious negative effect on educational achievement, peer relationships, social functioning, behavior, and self-esteem of children. However, the pooled prevalence of attention-deficit/hyperactivity disorder is not well known in Ethiopia. Therefore, the main objective of this systematic review and meta-analysis is to estimate the pooled prevalence of attention-deficit/hyperactivity disorder among children and adolescents in Ethiopia.

METHODS

PubMed, HINARI, Science Direct, Psych INFO, Google Scholar, African Journals Online, and cross-referenced were searched to identify relevant articles. Quality appraisal was done using the Joanna Briggs Institute checklist. Heterogeneity was tested using the I-square statistics. Publication bias was tested using a funnel plot visual inspection. Further, trim and fill analysis was done to correct publication bias.Forest plots and tables were used to present results. The random effect model was used to compute the pooled prevalence of attention-deficit/hyperactivity disorder among children and adolescents.

RESULTS

The overall pooled prevalence of attention-deficit/hyperactivity disorder among children and adolescents in Ethiopia was 14.2% (95% CI: 8.48, 22.83). Being male (OR: 2.19, 95% CI: 1.54; 3.12), being aged 6-11 years (OR: 3.67, 95% CI: 1.98; 6.83), low family socioeconomic status (OR: 3.45 95% CI: 2.17; 5.47), maternal complication during pregnancy (OR: 3.29, 95% CI: 1.97; 5.51) and family history of mental illness (OR: 3.83, 95% CI:2.17; 6.77) were factors associated with a higher odds of attention-deficit/hyperactivity disorder among children and adolescents.

CONCLUSIONS

The overall pooled prevalence of attention-deficit/hyperactivity disorder among children and adolescents is high in Ethiopia as compared to previous literature. To reduce the prevalence of attention-deficit/hyperactivity disorder among children and adolescents, emphasis has to be given to prevention, early detection, and management of pregnancy-related complications. Moreover, parents with mental illness should be supported and properly treated to reduce the impact of hostile parenting on their child's health.

TRIAL REGISTRATION

Registered in PROSPERO with ID: CRD42024536334.

Reciprocal relations between dimensions of attention-deficit/hyperactivity and anxiety disorders from preschool age to adolescence: sex differences in a birth cohort sample

BACKGROUND

Symptoms of anxiety and attention-deficit/hyperactivity disorder (ADHD) are prospectively related from childhood to adolescence. However, whether the two dimensions of ADHD-inattention and hyperactivity-impulsivity-are differentially related to anxiety and whether there are developmental and sex/gender differences in these relations are unknown.

METHODS

Two birth cohorts of Norwegian children were assessed biennially from ages 4 to 16 (N = 1,077; 49% girls) with diagnostic parent interviews used to assess symptoms of anxiety and ADHD. Data were analyzed using a random intercept cross-lagged panel model, adjusting for all unobserved time-invariant confounding effects.

RESULTS

In girls, increased inattention, but not hyperactivity-impulsivity, predicted increased anxiety 2 years later across all time-points and increased anxiety at ages 12 and 14 predicted increased inattention but not hyperactivity-impulsivity. In boys, increased hyperactivity-impulsivity at ages 6 and 8, but not increased inattention, predicted increased anxiety 2 years later, whereas increased anxiety did not predict increased inattention or hyperactivity-impulsivity.

CONCLUSIONS

The two ADHD dimensions were differentially related to anxiety, and the relations were sex-specific. In girls, inattention may be involved in the development of anxiety throughout childhood and adolescence and anxiety may contribute to girls developing more inattention beginning in early adolescence. In boys, hyperactivity-impulsivity may be involved in the development of anxiety during the early school years. Effective treatment of inattention symptoms in girls may reduce anxiety risk at all time-points, while addressing anxiety may decrease inattention during adolescence. Similarly, treating hyperactivity-impulsivity may reduce anxiety risk in boys during late childhood (at ages 8-10).

Prevalence, Correlates, and Comorbidities Among Young Adults Who Screened Positive for ADHD in South Korea During the COVID-19 Pandemic

OBJECTIVE

This study examined the prevalence, associated factors, and psychiatric comorbidities of adult ADHD during the COVID-19 pandemic by analyzing nationally representative data.

METHODS

Among the 5,511 respondents of the 2021 National Mental Health Survey, South Korea, 2,764 (18-49 years) were selected. The Korean versions of the Adult ADHD Self-Report Scale, Composite International Diagnostic Interview, and Structured Clinical Interview for Internet Gaming Disorder were used as diagnostic assessments.

RESULTS

The 6-month prevalence of positive screens for adult ADHD was 3.1%. In individuals aged 18 to 29 years exhibiting adult ADHD symptoms, high prevalence rates of alcohol use, depression, and Internet gaming disorders were observed in the last 12 months. Adults who screened positive for ADHD reported significantly lower life satisfaction and resilience, and higher loneliness and social isolation (vs. non-ADHD group).

CONCLUSION

Adult ADHD symptoms significantly influenced mental well-being, highlighting the need for an appropriate treatment/prevention system, particularly for individuals aged 18 to 29 years.

The Development and Content Validation of a Clinical Screening Scale to Identify Attention-Deficit Hyperactivity Disorder Cases Based on the Gender Perspective: An e-Delphi Study

BACKGROUND

Although many studies analyse gender differences in the clinical expression of Attention-Deficit Hyperactivity Disorder (ADHD) and prevalence studies show that girls with ADHD are underdiagnosed, there are no instruments that are sensitive to the detection of girls with ADHD.

OBJECTIVE

The objective of this study is to develop a self-report early detection instrument for boys and girls with ADHD aged 7 to 16, which includes the gender perspective and is sensitive to the detection of girls with ADHD.

METHODS

The scale was developed and the items that comprised it were created from the thematic analysis of ADHD and its evaluation in children based on the diagnostic criteria of the DSM-5-TR. A modified e-Delphi method involving a three-round web survey was used to establish a consensus on the content of the scale. Ten experts were recruited to form a professional panel. The panel members were asked to assess the differential symptomatology of ADHD in boys and girls, the dimensions to be evaluated, and the importance of scale items to evaluate the content.

RESULTS

A consensus was reached regarding 13 total items distributed in three dimensions: inattention; hyperactivity/impulsivity; and, a third dimension, internalisation, which includes symptoms most present in the expression of ADHD in girls.

CONCLUSIONS

To the best of our knowledge, the development of this scale using the Delphi method is the first specific scale used for identifying ADHD that also addresses the gender perspective and the differential symptomatology between boys and girls. However, we must proceed to the analysis of psychometric properties, as the scale requires an exhaustive study of its reliability and validity. We can anticipate that this scale will provide relevant and reliable information that can be used for the identification of ADHD in both boys and girls.

Sex and intelligence quotient differences in age of diagnosis among youth with attention-deficit hyperactivity disorder

OBJECTIVES

Attention-deficit/hyperactivity disorder (ADHD) is the most common neurodevelopmental condition and is characterized by inattention, hyperactivity, and impulsivity. Research suggests that some populations, such as females and individuals with high intelligence quotients may be a risk for late ADHD diagnosis and subsequent treatment. Our goal is to advance our understanding of ADHD diagnosis, by examining (1) how child sex and cognitive abilities together are related to the age of diagnosis and (2) whether symptom presentation, current internalizing and externalizing symptoms, and demographic factors are related to age of diagnosis.

METHODS

Our analyses contained children who completed the required tests (N = 568) from a pre-existing dataset of 1380 children with ADHD from the Province of Ontario Neurodevelopmental Disorders (POND) Network (pond-network.ca). First, we conducted a moderation analysis with sex as the predictor, cognitive abilities as the moderator, and age of diagnosis as the outcome. Second, we conducted correlation analyses examining how symptom presentation, current internalizing and externalizing symptoms, and demographic factors are related to age of diagnosis.

RESULTS

Higher IQ was related to a later age of diagnosis. Higher hyperactive-impulsive symptoms and externalizing symptoms were related to an earlier age of diagnosis. Internalizing symptoms were trend associated with a later age of diagnosis in girls. Higher socioeconomic status and non-White maternal ethnicity were related to later age of diagnosis.

CONCLUSIONS

IQ, sex, ADHD symptomology, internalizing symptoms, externalizing symptoms, and socio-demographic factors affect the age of diagnosis.

How Do Mental Disorders and Combinations of Disorders Affect the Odds of Injuries and Poisoning?

ABSTRACT

Injuries and poisoning are associated with mental disorders. The association may be stronger if comorbid mental illness is involved. This study explores whether selected mental disorders (stress, anxiety, depression, attention deficit hyperactivity disorder [ADHD], bipolar, obsessive-compulsive disorder [OCD], schizophrenia) are associated with injuries and poisoning and if the presence and frequency of comorbid mental illness affect these associations. Analyses utilize medical claims data for adult employees of a large corporation during 2017-2021. Approximately half or more of the index mental disorders experience comorbid mental illness. Odds of injury and poisoning are significantly greater for each mental disorder and tend to be significantly greater when comorbid mental illness exists ( vs . the mental disorder alone), especially for the associations involving poisoning. Schizophrenia alone and in combination with other mental illness has the strongest associations with injury and poisoning. OCD is only associated with injury and poisoning, and ADHD is only associated with poisoning, if accompanied by comorbid mental illness.

Time after time: failure to identify and support females with ADHD - a Swedish population register study

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) is associated with risk taking and negative health-related outcomes across the lifespan. Due to delay in referral and diagnostics, young females with ADHD may not be identified, nor appropriately supported by adequate interventions.

METHODS

A total of 85,330 individuals with ADHD, all of whom were residents in Stockholm County between January 01, 2011, and December 31, 2021, were included as participants in this population-based, cross-sectional cohort study. Population controls (n = 426,626) were matched by age, sex, and socioeconomic status (SES). Data was obtained from Regional Healthcare Data Warehouse of Region Stockholm (VAL) in Stockholm County. Exposure was ADHD-index, defined as the first record of either ICD-10 F90 diagnosis and/or ATC-code for stimulant or non-stimulant ADHD-medication during the study period. Primary outcome was age at ADHD-index. Secondary outcome measures were psychiatric comorbidity, pharmacological treatment, and health care utilization, prior to and after ADHD-index.

RESULTS

Females were older at ADHD-index (23.5 years, SD 13.8) compared to males (19.6 years, SD 13.9, 95% CI of difference 3.74-4.11). Overall, females with ADHD showed higher rates of psychiatric comorbidity, pharmacological treatment, and health care utilization, compared to males with ADHD and female controls.

CONCLUSIONS

Females with ADHD receive diagnosis and treatment for ADHD approximately 4 years later than males. They have a higher burden of comorbid psychiatric conditions and health care utilization, compared to males with ADHD and female controls, both prior to and after ADHD-index. To prevent long-term adverse consequences for females with ADHD, methods, and tools for early diagnosis and treatments that mitigate personal suffering and societal burden are warranted.

Sex Differences in Children with Uncomplicated Attention Deficit/Hyperactivity Disorder and Sleep Problems

BACKGROUND

Approximately 7.6% of children are diagnosed with attention deficit/hyperactivity disorder (ADHD), and sleep impairments affect 25-85%. There is a noticeable lack of research on girls and sex differences. The aim of this study was to examine sex differences in children with uncomplicated ADHD and sleep problems.

METHODS

Cross-sectional baseline data were retrieved from a randomized controlled trial with weighted blankets (55 boys and 41 girls, 6-14 years) on a cohort recently diagnosed with uncomplicated ADHD and sleep problems. Differences between boys and girls in ADHD symptoms, objectively and subjectively measured sleep, anxiety, and functioning were examined via parent- or self-reported validated instruments.

RESULTS

Girls reported significantly lower (worse) satisfaction with well-being, life overall, and school, but not for family. Parents reported more sleep anxiety and night-time wakings among boys, but no sex differences in other measures and also not in self-reported measures or objective sleep measures. Children who reported worry, sadness, or unhappiness had more sleep problems.

CONCLUSIONS

Boys with ADHD and sleep problems may need support with sleep-related anxiety and night-time wakings, while girls may require support with overall functioning. Additionally, children who express feelings of worry, sadness, or unhappiness alongside their ADHD symptoms should have attention given to their sleep.

Access to early diagnosis for attention-deficit/hyperactivity disorder among children and adolescents in Mexico City at specialized mental health services

BACKGROUND

In Mexico, this pioneering research was undertaken to assess the accessibility of timely diagnosis of Dyads [Children and adolescents with Attention Deficit Hyperactivity Disorder (ADHD) and their primary caregivers] at specialized mental health services. The study was conducted in two phases. The first phase involved designing an "Access Pathway" aimed to identify barriers and facilitators for ADHD diagnosis; several barriers, with only the teacher being identified as a facilitator. In the second phase, the study aimed to determine the time taken for dyads, to obtain a timely diagnosis at each stage of the Access Pathway. As well as identify any disparities based on gender and socioeconomic factors that might affect the age at which children can access a timely diagnosis.

METHOD

In a retrospective cohort study, 177 dyads participated. To collect data, the Acceda Survey was used, based on the robust Conceptual Model Levesque, 2013. The survey consisted of 48 questions that were both dichotomous and polytomous allowing the creation of an Access Pathway that included five stages: the age of perception, the age of search, the age of first contact with a mental health professional, the age of arrival at the host hospital, and the age of diagnosis. The data was meticulously analyzed using a comprehensive descriptive approach and a nonparametric multivariate approach by sex, followed by post-hoc Mann-Whitney's U tests. Demographic factors were evaluated using univariable and multivariable Cox regression analyses.

RESULTS

71% of dyads experienced a late, significantly late, or highly late diagnosis of ADHD. Girls were detected one year later than boys. Both boys and girls took a year to seek specialized mental health care and an additional year to receive a formal specialized diagnosis. Children with more siblings had longer delays in diagnosis, while caregivers with formal employment were found to help obtain timely diagnoses.

CONCLUSIONS

Our findings suggest starting the Access Pathway where signs and symptoms of ADHD are detected, particularly at school, to prevent children from suffering consequences. Mental health school-based service models have been successfully tested in other latitudes, making them a viable option to shorten the time to obtain a timely diagnosis.

Prevalence of ADHD among Black Youth Compared to White, Latino and Asian Youth: A Meta-Analysis

OBJECTIVE

To systematically review the prevalence of Attention Deficit Hyperactivity Disorder (ADHD) among Black children and adolescents compared to White, Latino and Asian children and adolescents.

METHOD

Peer-reviewed articles were identified in seven databases and included if they reported prevalence of ADHD among Black children and adolescents living in a minority context and compared rates to at least one of White, Latino or Asian samples. A total of 7050 articles were retrieved and 155 articles were subjected to full evaluation. Twenty-three studies representing 26 independent samples were included.

RESULTS

The pooled sample size was n = 218,445 (k = 26), n = 835,505 (k = 25), n = 493,417 (k = 24), and n = 66,413 (k = 7) of Black, White, Latino, and Asian participants, respectively. Pooled prevalence rate of ADHD was 15.9% (95%CI 11.6% - 20.7%) among Black children and adolescents, 16.6% (95%CI 11.6% - 22.2%) among Whites, 10.1% (95%CI 6.9% - 13.8%) among Latinos and 12.4% (95%CI 1.4% - 31.8%) among Asians. There was no significant difference in prevalence between ethnic groups, whereas both Black and White children and adolescents had marginally statistically significant higher prevalence than Asians. The results of a meta-regression analysis showed no moderating effects of the type of sample and the year of publication of studies. A significant publication bias was observed, suggesting that other moderators were not identified in the present systematic review.

CONCLUSION

In contrast to the assertion in the DSM-5 that clinical identification among Black children and adolescents is lower than among White children and adolescents, the present meta-analysis suggests similar rates of ADHD among these two groups. The importance of considering cultural appropriateness of assessment tools and processes is emphasized.

Sex-differential patterns of neuropsychological functioning in adults with attention-deficit/hyperactivity disorder

BACKGROUND

The sex-differential prevalence of attention-deficit/hyperactivity disorder (ADHD) varies across the lifespan, but little is known about sex differences in executive functions in adults with ADHD.

METHODS

We assessed 261 adults, aged 18-40 years, diagnosed with ADHD (170 males [assigned at birth], aged 25.81 ± 5.49; 91 females, aged 27.76 ± 5.42) and 308 neurotypical adults (176 males, aged 24.62 ± 5.14; 132 female, aged 25.37 ± 5.42) via psychiatric interviews to confirm ADHD and other psychiatric diagnoses. They were assessed by the Cambridge Neuropsychological Testing Automated Battery (CANTAB) on Reaction Time (arousal/processing speed), Rapid Visual Information Processing (sustained attention), Spatial Span (spatial memory), Spatial Working Memory, Intradimentional/Extradimensional Shift (set-shifting), and Stocking of Cambridge (spatial planning). The primary analyses were adjusted for age, full-scale IQ, and co-occurring psychiatric conditions.

RESULTS

Adults with ADHD had various co-occurring psychiatric conditions without sex differences in ADHD-neurotypical differences. Both adult males and females with ADHD performed poorer in all CANTAB tasks than same-sex neurotypical adults. Significant sex-moderating effects were observed in neuropsychological performance, including greater ADHD-neurotypical differences in arousal for females than males and in location memory for spatial tasks in males than females.

CONCLUSION

There were no sex-moderating effects in the presence of co-occurring psychiatric conditions in adult ADHD. However, there were sex-moderating effects on how ADHD related to neuropsychological functioning in adulthood. ADHD was associated with more challenges in arousal/processing speed in females and more challenges in strategy use or inhibition in spatial memory in males.

Attention-deficit/hyperactivity disorder (ADHD) and anxiety during the COVID-19 pandemic: Implications for internalizing behaviors in college students

Objective: The purpose of this study was to delineate the moderating roles of negative experiences related to the coronavirus disease 2019 (COVID-19) on the association between Attention-Deficit/Hyperactivity Disorder symptoms and anxiety symptoms and internalizing behaviors during Fall 2020. Method: Participants were 200 college students. Using a moderated moderation model, researchers found that attention-deficit/hyperactivity disorder symptoms predicted anxiety symptoms for those who internalized behaviors and experienced COVID-19 more negatively. Results: Results suggested that ADHD symptoms were playing a role in the manifestation of anxiety symptoms during the COVID-19 pandemic and that college students who internalize behaviors experienced worsened ADHD symptoms. Conclusion: Clinical implications underscore the importance of providing mental health resources for students on campus, particularly during the COVID-19 pandemic. Specialized treatment may include help with developing time management skills and teaching interventions such as mindfulness exercises that may help alleviate anxiety and improve attention and concentration.

Perceived associations between the menstrual cycle and Attention Deficit Hyperactivity Disorder (ADHD): A qualitative interview study exploring lived experiences

BACKGROUND

The research gap regarding Attention Deficit Hyperactivity Disorder (ADHD) in people who were assigned female at birth has led to a lack of knowledge and adequate approaches in clinical practice, as well as diagnosis processes. Recent studies report potential associations between reproductive hormones and ADHD, but existing research remains scarce.

AIM

This study aims to explore the experiences of people who perceive an association between their menstrual cycle and their ADHD symptoms.

METHODOLOGY

Design and Method. A qualitative research design with an inductive approach was used. Ten participants were interviewed, using semi-structured, in-depth interviews. The data was transcribed, coded, and analyzed using reflexive thematic analysis according to Braun and Clarke.

RESULTS

Findings show participant's perceived associations between their ADHD and their menstrual cycle: participants reported experiencing ADHD symptom mor severe during the mid-luteal phase of the menstrual cycle. Other results showed uncertainty around ADHD medication in relation to the cycle and varied experiences with health care encounters as well as heightened challenged around menstrual health management.

CONCLUSIONS

This study provides insights to how perceived associations between ADHD and the menstrual cycle might be experienced. This report highlights the need for further research and theory about the potential associations between ADHD and reproductive hormones. The researchers strongly suggested that forthcoming ADHD studies consider times of key hormonal changes, such as puberty and menarche, menopause, hormonal birth control, pregnancy, hormone treatment, and more.

Sex Differences in ADHD: Review and Priorities for Future Research

PURPOSE OF REVIEW

In childhood, attention-deficit/hyperactivity disorder (ADHD) is diagnosed three to 16 times more frequently in males compared to females, yet in adulthood, nearly equivalent numbers of males and females are diagnosed with ADHD. Relatively few studies have prioritized examination of sex differences in ADHD even though sex differences may have critical implications for the identification and treatment of ADHD in females and males. This review highlights current research on sex differences in ADHD across the lifespan that has emerged from cross-sectional and prospective longitudinal studies of youth, adult-ascertained samples, and registry studies.

RECENT FINDINGS

Accumulating research suggests that both males and females with ADHD experience widespread impairment across the lifespan. Some evidence of sex differences emerged, although effects have generally been modest in size. Continued research that includes females and males with ADHD is needed to clarify the nature of sex differences in ADHD. Research that focuses on equitable identification of ADHD in males and females, disentangles the effects of sex and gender, probes underlying mechanisms of sex differences, and addresses the clinical impact of sex differences in ADHD must be prioritized.

Validation of the Self-Report Version of the German Strengths and Weaknesses of ADHD Symptoms and Normal Behavior Scale (SWAN-DE-SB)

Adults with attention-deficit/hyperactivity disorder (ADHD) experience impairing levels of inattention and/or hyperactivity-impulsivity, while individuals without ADHD experience these symptoms to a lesser extent. Yet, ADHD self-report scales so far hardly captured continuous distributions across the general population. In addition, they focused on weaknesses and ignored strengths. To address these shortcomings, we present here the Strengths and Weaknesses of ADHD and Normal-Behavior Scale Self-Report (SWAN-DE-SB). The normal distribution of the data collected and the scale's internal consistency, and factorial and convergent validity were assessed using data from a general population sample. Its clinical utility was evaluated by comparing scores from a clinical sample and a sample of individuals without ADHD and by calculating optimal cut-off values for specificity and sensitivity. The SWAN-DE-SB demonstrated normal distribution of the data collected, high internal consistency, and factorial and convergent validity. It reliably discriminated individuals with and without ADHD, with high specificity and sensitivity. It should therefore be considered a psychometrically convincing measure to assess strengths and weaknesses of ADHD symptoms and normal behavior in clinical and general population samples.

Differences in Ex-Gaussian Parameters from Response Time Distributions Between Individuals with and Without Attention Deficit/Hyperactivity Disorder: A Meta-analysis

Attention Deficit Hyperactivity Disorder (ADHD) is one of the most prevalent neurodevelopmental disorders in childhood and adolescence. Differences in reaction times (RT) in cognitive tasks have been consistently observed between ADHD and typical participants. Instead of estimating means and standard deviations, fitting non-symmetrical distributions like the ex-Gaussian, characterized by three parameters (µ, σ, and τ), account for the whole RT distributions. A meta-analysis is performed with all the available literature using ex-Gaussian distributions for comparisons between individuals with ADHD and controls. Results show that τ and σ are generally greater for ADHD samples, while µ tends to be larger for typical groups but only for younger ages. Differences in τ are also moderated by ADHD subtypes. τ and σ show, respectively, quadratic and linear relationships with inter-stimulus intervals from Continuous Performance Test and Go/No Go tasks. Furthermore, tasks and cognitive domains influence the three parameters. Interpretations of ex-Gaussian parameters and clinical implications of these findings are also discussed. Fitting ex-Gaussian distributions to RT data is a useful way to explore differences between individuals with ADHD and healthy controls.

Sensorimotor dysfunction due to developmental manganese exposure is less severe in adult female than male rats and partially improved by acute methylphenidate treatment

Epidemiological studies have reported associations between elevated manganese (Mn) exposure and poorer psychomotor performance in children. Our studies in adult male rats have established that this relationship is causal and that prolonged methylphenidate (MPH) treatment is efficacious in treating this area of dysfunction. However, it is unclear if sensitivity to these Mn deficits differs between females and males, and whether existing pharmacological therapies are efficacious in improving sensorimotor dysfunction in females. To address these questions, we used our rat model of childhood environmental Mn exposure and the Montoya staircase test to determine whether 1) there are sex differences in the lasting sensorimotor dysfunction caused by developmental Mn exposure, and 2) MPH treatment is efficacious in ameliorating the sensorimotor deficits in females. Female and male neonates were treated orally with Mn (50 mg Mn/kg/d) from postnatal day 1 to 21 and evaluated for skilled forelimb sensorimotor performance as adults. Subsequently, the efficacy of acute oral MPH treatment (doses of 0, 0.5, and 3.0 mg MPH/kg/d) was assessed in females using a within-subject MPH treatment design. Developmental postnatal Mn exposure produced lasting sensorimotor reaching and grasping deficits that were milder in females than in males. Acute MPH treatment of Mn-exposed females with the 0.5 mg/kg/d dose attenuated the reaching dysfunction without alleviating grasping dysfunction. These findings show sex-based variations in sensitivity to the sensorimotor impairment caused by developmental Mn exposure, and they are consistent with prior studies showing less vulnerability of females to Mn-induced dysfunction in other functional domains, possibly due to the protective effects of estrogen. Given our previous work showing the efficacy of MPH treatment to alleviate Mn-induced inattention, impulsiveness, and sensorimotor dysfunctions in adult male rats, they also highlight the need for further research into sex-based differences in cognitive and behavioral areas of brain function, and the efficacy of therapeutics in treating behavioral dysfunction in females. Supported by NIEHS R01ES028369.

Rising Trends of Childhood Attention-Deficit/Hyperactivity Disorder in a Large Integrated Healthcare Delivery System in Southern California, 2010-2021

OBJECTIVE

To evaluate trends of attention-deficit/hyperactivity disorder (ADHD) diagnosis rates among children aged 5-17 years over the past decade (2010-2021) and to investigate whether there have been differences in temporal changes based on race and ethnicity, sex, or income.

STUDY DESIGN

Childhood ADHD diagnosis was ascertained from electronic health records using International Classification of Diseases ninth revision (314.xx) and International Classification of Diseases tenth revision (F90.x) codes. Data were stratified by child's sex, race and ethnicity, and household income, and rates of ADHD were estimated before and after adjustment for potential confounders.

RESULTS

The overall ADHD diagnosis rates increased from 3.5% in 2010 to 4.0% in 2021. ADHD diagnosis was most prevalent among White children (6.1%), then Black (4.6%), Other/multiple (3.7%), Hispanic (3.1%), and Asian/Pacific Islander (PI) (1.7%). ADHD was also highly prevalent among boys (73.3%) or family income≥$70,000 (50.0%). ADHD diagnosis increased among Black (4.2% to 5.1%), Hispanic (2.8% to 3.6%), and Asian/PI children (1.5% to 2.0%) but remained stable for White (6.2% to 6.1%) and Other/multiple race/ethnic children (3.7% to 3.7%). Increases in the prevalence among girls were also observed.

CONCLUSION

The prevalence of ADHD in children has risen with the largest increases observed for Black, Hispanic, and Asian/PI children. Rates among less affluent families and girls have also been increasing, narrowing the gaps in diagnosis rates previously observed. These increases may reflect improvements in screening and provision of care among demographics where ADHD has been historically underdiagnosed.

Measurement invariance of Attention Deficit/Hyperactivity Disorder symptom criteria as rated by parents and teachers in children and adolescents: A systematic review

This systematic review aimed to establish the extent to which each Attention Deficit/Hyperactivity Disorder (ADHD) symptom criterion is being assessed without being influenced (biased) by factors such as informant, sex/gender, and age. Measurement invariance (MI) testing using confirmatory factor analysis (CFA) is the prime statistical method to ascertain how these factors may affect the measurement and colour the perception or interpretation of symptom criteria. Such effects (non-invariance) can be operationalised in the form of altered association of a symptom criterion with the measured trait (expressed via variations in CFA loadings which represent the weight of each symptom criterion) due to the factor(s) and/or artificially alter the probability of endorsement of a particular symptom criterion (expressed via variations in the CFA threshold(s) representing how mild or severe a given symptom is). Based on a pre-registered protocol (CRD42022276105), we searched PubMed, Global Health, Embase and PsycInfo up to 21-02-23 for studies that included MI assessments on specific ADHD symptom criteria in individuals aged 0-18 years old, using parental and/or teacher report. Self-reports were excluded, given the poor reliability of self-report in ADHD. All included studies met specific COnsensus-based Standards for the selection of health Measurement Instruments (COSMIN) criteria. Results were synthesised in tabular form, grouping results by factors (e.g. informant) from 44 studies retained. Most comparisons indicated both metric (same loadings) and scalar invariance (same thresholds) with regard to informant, gender, age, temporal (repeated assessments) and co-morbidity. Therefore, the available evidence supports the current diagnostic criteria. However, findings could have been improved by systematic reporting of the direction of bias and its effect size. There appears to be a bias towards reporting MI instead of non-invariance. More studies in the literature are needed where the amalgamation of information provided by different informs and the association of specific symptoms with comorbidity are analysed.

Exploring sex differences: insights into gene expression, neuroanatomy, neurochemistry, cognition, and pathology

Increased knowledge about sex differences is important for development of individualized treatments against many diseases as well as understanding behavioral and pathological differences. This review summarizes sex chromosome effects on gene expression, epigenetics, and hormones in relation to the brain. We explore neuroanatomy, neurochemistry, cognition, and brain pathology aiming to explain the current state of the art. While some domains exhibit strong differences, others reveal subtle differences whose overall significance warrants clarification. We hope that the current review increases awareness and serves as a basis for the planning of future studies that consider both sexes equally regarding similarities and differences.

Exploring Differences in Physical Health in Young Children With and Without ADHD

OBJECTIVE

To assess differences in child physical health outcomes and metrices associated with obesity in a sample of predominantly Hispanic/Latinx young children with and without attention-deficit/hyperactivity disorder (ADHD).

METHODS

Participants included 127 children diagnosed with ADHD and 96 typically developing (TD) children between 4 and 7 years of age. Objective measures of children's body composition, fitness, and physical activity were conducted. Parents of children completed food recalls to assess their child's dietary intake, diet quality was calculated based on the Healthy Eating Index-2015, and parents completed a survey about their family's health habits.

RESULTS

Logistic regression revealed that those with ADHD were more likely to be classified as having an overweight or obese (Ov/O) body mass index (BMI). Linear regression analyses indicated that children with ADHD performed worse on a fitness test and consumed more calories relative to TD children. Moderation analyses indicated that sex differences in steps were prominent in our TD sample, but not among those with ADHD.

CONCLUSIONS

Young children with ADHD are at greater risk for having an Ov/O BMI, being less fit, and eating a greater intake of calories compared to TD children.

Labour market integration among young adults diagnosed with attention-deficit/hyperactivity disorder (ADHD) at working age

METHODS

Multiple Swedish nationwide registers were used to identify 8045 individuals, aged 20-29, with an incident diagnosis of ADHD 2006-2011. Labour market integration was conceptualized according to the core-peripheral model as a continuum from a strong (core) to a weak (peripheral) connection to the labour market. Sequence analyses categorized clusters of labour market integration, from 1 year before to 5 years after their ADHD diagnosis for individuals diagnosed with ADHD and a matched control group without ADHD. Multinomial logistic regression computed odds ratios (ORs) with 95% confidence intervals (CIs) between sociodemographic factors and comorbid disorders and the identified clusters.

RESULTS

About one-fourth of the young adults diagnosed with ADHD belonged to clusters characterized by a transition to a mainly peripheral labour market position, which was approximately four-times higher compared to controls without ADHD. Foremost, those living in small cities/villages (OR 1.9; CI 1.5-2.2), those having comorbid autism-spectrum disorder (OR 13.7; CI 6.8-27.5) or schizophrenia/psychoses (OR 7.8; CI 3.8-15.9) were associated with a transition towards a peripheral labour market position throughout the study period. Those with a high educational level (OR 0.1; CI 0.1-0.1), and men (OR 0.7; CI 0.6-0.8) were less likely to have a peripheral labour market position.

CONCLUSIONS

Young adults diagnosed with ADHD are four-times more likely to be in the peripheral labour market position compared to those without ADHD. To increase labour market participation, special attention is warranted to those with low educational level, those living outside big cities and those with comorbid mental disorders.

Time-Perception Deficits in Attention-Deficit/Hyperactivity Disorder: A Systematic Review and Meta-Analysis

The present meta-analysis quantified the deficit in time perception in Attention-Deficit/Hyperactivity Disorder (ADHD) throughout the lifespan and examined potential moderators of this deficit. Our sample of 824 effect sizes showed a mean g of 0.688 that was moderated by the age of the sample and working memory. Separate moderator analyses for samples below or above the age of 18 showed that the link with working memory only applied to the samples below the age of 18, whereas an effect of ADHD subtype only applied to samples 18 and above. The discussion highlights the implications for remediation and avenues for future research.

The emerging evidence on the association between symptoms of ADHD and gaming disorder: A systematic review and meta-analysis

The co-existence of gaming disorder (GD) with other mental health problems has been widely reported. Despite the growing research interest in the comorbidity of GD with attention-deficit/hyperactivity disorder (ADHD), to date, no quantitative synthesis has been performed. The present study comprised a systematic literature search using Scopus, Science Direct, Web of Science, and PubMed databases. Three types of studies were included in the analyses: studies reporting (i) correlation coefficients between the symptoms of GD and ADHD, (ii) means, and standard deviations for comparison of GD severity between ADHD/non-ADHD individuals, and (iii) comparison of ADHD severity between GD/non-GD individuals. The results indicated a moderate relationship between GD and ADHD symptom severity when both subdomains of ADHD were combined (r = 0.296), and also when only inattention (r = 0.306) or hyperactivity (r = 0.266) symptoms were analyzed, which was also confirmed in a structural equation model meta-analysis. Studies showed a large average difference comparing the GD symptom severity of ADHD and non-ADHD individuals (g = 0.693), or ADHD symptom severity of GD and non-GD individuals (g = 0.854). In some cases, higher estimates of association were reported among studies that (i) had a higher proportion of males, (ii) assessed problematic internet use among predominantly videogame player samples rather than assessing only GD, and (iii) had been more recently published. The present review shows that this is an emerging field demonstrating significant results in cross-sectional correlational studies. However, future research should apply more rigorous methodologies to investigate the relationship further (e.g., longitudinal studies and studies using professional/clinical ratings and diagnosis). These results suggest that screening and treatment for ADHD among individuals with gaming disorder is necessary, and individuals with ADHD should be made aware of their higher susceptibility to gaming disorder.

Utility for Clinical Practice of a Bifactor ADHD Model in an Elementary School Population in Mexico

We assessed the appropriateness of the bifactor model for a Mexican ADHD symptom questionnaire (BMQ-ADHD) applied to parents and teachers of elementary school children. With a sample of 765 reports of children's behavior (48.7% with ADHD A1 criteria, 42.6% girls, mean age 8.5 years [± 1.6 sd]), we examined construct validity, measurement invariance, differences for gender and school level, and the appropriateness of using summed scores. The BMQ-ADHD questionnaire was characterized by good construct validity for the bifactor model for parents' and teachers' reports. For both corpora, we detected invariance for gender and school level. There were differences in ADHD symptoms by gender, but not by school year. The summed scores may represent the factors accurately for females but may present difficulty for males in the parents' questionnaires. The present study revealed good BMQ-ADHD psychometric properties for a unidimensional-hierarchical ADHD scale segregated by gender for parents' and teachers' reports.

Prevalence of Attention Deficit Hyperactivity Disorder in Girls With Central Precocious Puberty

OBJECTIVE

The purpose of the current study was to examine the prevalence of attention deficit hyperactivity disorder (ADHD) in girls with central precocious puberty.

METHOD

Girls with central precocious puberty were prospectively recruited from the pediatric clinic. Screening was done with ADHD Rating Scale (ADHD-RS) and Child Behavior Checklist (CBCL). Those who screened positive on ADHD-RS were referred for the diagnostic evaluation which included a Computerized Performance Test (CPT) and a clinical interview conducted by a child adolescent psychiatrist.

RESULTS

Among the 81 girls (mean age = 8.97 ± 0.91) who completed the study, 11 girls (13.58%) were diagnosed with ADHD: 5 of them were inattentive type and 6 of them were combined type.

CONCLUSION

The present exploratory study showed that the prevalence of ADHD in girls with central precocious was higher than the known worldwide prevalence of ADHD in children.

Incidence, prevalence, and global burden of ADHD from 1990 to 2019 across 204 countries: data, with critical re-analysis, from the Global Burden of Disease study

Data on incidence, prevalence and burden of ADHD are crucial for clinicians, patients, and stakeholders. We present the incidence, prevalence, and burden of ADHD globally and across countries from 1990 to 2019 from the Global Burden of Disease (GBD) study. We also: (1) calculated the ADHD prevalence based on data actually collected as opposed to the prevalence estimated by the GBD with data imputation for countries without prevalence data; (2) discussed the GBD estimated ADHD burden in the light of recent meta-analytic evidence on ADHD-related mortality. In 2019, GBD estimated global age-standardized incidence and prevalence of ADHD across the lifespan at 0.061% (95%UI = 0.040-0.087) and 1.13% (95%UI = 0.831-1.494), respectively. ADHD accounted for 0.8% of the global mental disorder DALYs, with mortality set at zero by the GBD. From 1990 to 2019 there was a decrease of -8.75% in the global age-standardized prevalence and of -4.77% in the global age-standardized incidence. The largest increase in incidence, prevalence, and burden from 1990 to 2019 was observed in the USA; the largest decrease occurred in Finland. Incidence, prevalence, and DALYs remained approximately 2.5 times higher in males than females from 1990 to 2019. Incidence peaked at age 5-9 years, and prevalence and DALYs at age 10-14 years. Our re-analysis of data prior to 2013 showed a prevalence in children/adolescents two-fold higher (5.41%, 95% CI: 4.67-6.15%) compared to the corresponding GBD estimated prevalence (2.68%, 1.83-3.72%), with no significant differences between low- and middle- and high-income countries. We also found meta-analytic evidence of significantly increased ADHD-related mortality due to unnatural causes. While it provides the most detailed evidence on temporal trends, as well as on geographic and sex variations in incidence, prevalence, and burden of ADHD, the GBD may have underestimated the ADHD prevalence and burden. Given the influence of the GBD on research and policies, methodological issues should be addressed in its future editions.

Impact of a Publicly-Funded Pharmacare Program on Prescription Stimulant use Among Children and Youth: A Population-Based Observational Natural Experiment

OBJECTIVE

Stimulants are first-line pharmacotherapy for individuals with attention-deficit hyperactivity disorder. However, disparities in drug coverage may contribute to inequitable treatment access. In January 2018, the government of Ontario, Canada, implemented a publicly-funded program (OHIP+) providing universal access to medications at no cost to children and youth between the ages of 0 and 24. In April 2019, the program was amended to cover only children and youth without private insurance. We studied whether these policy changes were associated with changes in prescription stimulant dispensing to Ontario children and youth.

METHODS

We conducted a population-based observational natural experiment study of stimulant dispensing to children and youth in Ontario between January 2013 and March 2020. We used interventional autoregressive integrated moving average models to estimate the association between OHIP+ and its subsequent modification with stimulant dispensing trends.

RESULTS

The implementation of OHIP+ was associated with a significant immediate increase in the monthly rate of stimulant dispensing of 53.6 individuals per 100,000 population (95% confidence interval [CI], 36.8 to 70.5 per 100,000) and a 14.2% (95% CI, 12.8% to 15.6%) relative percent increase in stimulant dispensing rates between December 2017 and March 2019 (1198.6 vs. 1368.7 per 100,000 population). The April 2019 OHIP+ program amendment was associated with an increase in monthly stimulant dispensing trends of 10.2 individuals per 100,000 population (95% CI, 5.0 to 15.5), with rates increasing 7.5% (95% CI, 6.2% to 8.7%) between March 2019 and March 2020 (1368.7 vs. 1470.8 per 100,000 population). These associations were most pronounced among males, children and youth living in the highest income neighbourhoods and individuals aged 20 to 24.

CONCLUSION

A publicly-funded pharmacare program was associated with more children and youth being dispensed stimulants.

Gender and Age Differences in ADHD Symptoms and Co-occurring Depression and Anxiety Symptoms Among Children and Adolescents in the BELLA Study

Attention-deficit/hyperactivity disorder (ADHD) is one of the most diagnosed neurodevelopmental disorders of childhood. Current studies addressing gender and age differences in ADHD are lacking. The present study aims to fill this research gap by dimensionally evaluating gender and age differences in ADHD symptoms, as measured by a DSM-5-based parent rating scale, in children and adolescents who participated in the two-year follow-up of the community-based BELLA study (n = 1326). Associations between ADHD symptoms and depression symptoms and anxiety symptoms were also examined. Multiple linear regressions revealed significant associations between gender and all ADHD symptoms. Age was significantly associated with hyperactive/impulsive symptoms. Additional multiple linear regressions demonstrated significant positive associations between depression and anxiety symptoms and ADHD symptoms. Further, female gender was found to be positively associated with both depression and anxiety symptoms. These findings may suggest a need for more gender-specific approaches to ADHD diagnosis and treatment, as well as more research into the intersections of ADHD and depression and anxiety symptoms in children and adolescents.

Resting-state EEG dynamics help explain differences in response control in ADHD: Insight into electrophysiological mechanisms and sex differences

Reductions in response control (greater reaction time variability and commission error rate) are consistently observed in those diagnosed with attention-deficit/hyperactivity disorder (ADHD). Previous research suggests these reductions arise from a dysregulation of large-scale cortical networks. Here, we extended our understanding of this cortical-network/response-control pathway important to the neurobiology of ADHD. First, we assessed how dynamic changes in three resting-state EEG network properties thought to be relevant to ADHD (phase-synchronization, modularity, oscillatory power) related with response control during a simple perceptual decision-making task in 112 children/adolescents (aged 8-16) with and without ADHD. Second, we tested whether these associations differed in males and females who were matched in age, ADHD-status and ADHD- subtype. We found that changes in oscillatory power (as opposed to phase-synchrony and modularity) are most related with response control, and that this relationship is stronger in ADHD compared to controls. Specifically, a tendency to dwell in an electrophysiological state characterized by high alpha/beta power (8-12/13-30Hz) and low delta/theta power (1-3/4-7Hz) supported response control, particularly in those with ADHD. Time in this state might reflect an increased initiation of alpha-suppression mechanisms, recruited by those with ADHD to suppress processing unfavourable to response control. We also found marginally significant evidence that this relationship is stronger in males compared to females, suggesting a distinct etiology for response control in the female presentation of ADHD.

Clinical utility of new cut-off scores for the world health organization ADHD self-report scale among adolescents in psychiatric outpatient care

Previous analyses of the proposed cut-off score for the 18-item World Health Organization ADHD Self-Report Scale (ASRS-18) among psychiatrically referred adolescents have shown limited clinical utility. This prospective study examined the diagnostic accuracy and clinical utility of new cut-off scores of the ASRS-18 in a consecutive sample of 111 Swedish adolescent psychiatric outpatients. Using the Kiddie Schedule of Affective Disorders and Schizophrenia (K-SADS) as the reference standard and based on predefined sensitivity and specificity criteria, multiple new general and sex-specific cut-off scores were evaluated. Results showed that clinical utility was greater for sex-specific cut-off scores than for general cut-off scores. The greatest change in pre-test to post-test probability of ADHD diagnosis was observed with a balanced, high-specificity diagnostic cut-off score for girls, where the probability of ADHD increased from 40% pre-test to 82% post-test. The proposed new cut-off levels for the ASRS-18 are useful for the detection and identification of ADHD among adolescents in general psychiatric outpatient settings.

Parenting Practices May Buffer the Impact of Adversity on Epigenetic Age Acceleration Among Young Children With Developmental Delays

This study examined whether children exposed to adversity would exhibit lower epigenetic age acceleration in the context of improved parenting. Children with developmental delays and externalizing behavior problems (N = 62; Mage = 36.26 months; 70.97% boys, 29.03% girls; 71% Latinx, 22.6% Black) were drawn from a larger randomized controlled trial (RCT), which randomized them to receive Internet-delivered parent-child interaction therapy (iPCIT; n = 30) or community referrals as usual (RAU; n = 32). Epigenetic age acceleration was estimated with the pediatric buccal epigenetic clock, using saliva. Adversity was assessed using parent, family, and neighborhood-level cumulative-risk indicators. Adversity interacted with Time 2 (T2) observations of positive and negative-parenting practices to predict epigenetic age acceleration 1.5 years later, regardless of treatment assignment. Children exposed to more adversity displayed lower epigenetic age acceleration when parents evidenced increased positive (b = -0.15, p = .001) and decreased negative (b = -0.12, p = .01) parenting practices.

Sustainable labour market participation among working young adults with diagnosed attention deficit/hyperactivity disorder (ADHD)

Background

The aims were to study the sustainability of labour-market participation five years after an incident diagnosis of attention-deficit/hyperactivity disorder (ADHD) among young adults with gainful employment, and to examine the impact of sociodemographic-, work- and health-related factors on these findings.

Methods

Swedish registers identified 2517 individuals, 19-29 years old, with an incident diagnosis of ADHD and gainful employment during 2006-2011. Labour-market participation was measured by the core-peripheral model, a model that measures the connection to the labour market from a weak connection (peripheral) to a strong connection (core). Sequence analysis analysed clusters of labour-market participation, from one year before and up to five years after diagnosis. Odds ratios (OR) with 95% confidence intervals (CI) between sociodemographic factors, comorbid disorders, and the identified clusters were analysed by multinomial logistic regression.

Results

Five clusters of labour-market participation were identified: 60% of individuals belonged to a cluster that maintained labour-market participation throughout the study period (core, close to core); 20% belonged to a cluster with a transition to a weak connection to the labour market (close to peripheral, peripheral); and 20% belonged to a cluster with "middle" labour-market participation, characterised by having long periods of sick leave and unemployment. Individuals with elementary school as highest attained education (OR:4.03;CI:2.35-6.93), comorbid mental disorders (OR:2.77;CI:2.10-3.66), or living in villages/small cities (OR:1.77;CI:1.25-2.51) were most likely to belong to a cluster transitioning towards a "peripheral" labour-market participation. Men were less likely to have peripheral labour-market participation than women (OR:0.55;CI:0.40-0.75).

Conclusions

Over half of working individuals with ADHD maintain a strong attachment to the labour market several years after their first diagnosis of ADHD. Therefore, it is important to target those who have problems maintaining a position in the labour market, including women, those with low educational levels, and those living outside large cities.

Peripheral Inflammatory Markers in Autism Spectrum Disorder and Attention Deficit/Hyperactivity Disorder at Adolescent Age

Autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD) are associated with immune dysregulation. We aimed to estimate the pro- and anti-inflammatory activity/balance in ASD and ADHD patients at a little-studied adolescent age with respect to sex. We evaluated 20 ASD patients (5 girls, average age: 12.4 ± 1.9 y), 20 ADHD patients (5 girls, average age: 13.4 ± 1.8 y), and 20 age- and gender-matched controls (average age: 13.2 ± 1.9 y). The evaluated parameters included (1) white blood cells (WBCs), neutrophils, monocytes, lymphocytes, platelets, platelet distribution width (PDW), mean platelet volume, and derived ratios, as well as (2) cytokines-interferon-gamma, interleukin (IL)-1α, IL-1β, IL-2, IL-4, IL-6, IL-8, and IL-10, tumor necrosis factor-alpha (TNF-α), and derived profiles and ratios. ASD adolescents showed higher levels of WBC, monocytes, IL-1α, IL-1β, IL-2, IL-4, IL-6, IL-8, and IL-10, macrophages (M)1 profile, and anti-inflammatory profile than the controls, with ASD males showing higher monocytes, IL-6 and IL-10, anti-inflammatory profile, and a lower T-helper (Th)1/Th2+T-regulatory cell ratio than control males. The ADHD adolescents showed higher levels of PDW, IL-1β and IL-6, TNF-α, M1 profile, proinflammatory profile, and pro-/anti-inflammatory ratio than the controls, with ADHD females showing a higher TNF-α and pro-/anti-inflammatory ratio than the control females and ADHD males showing higher levels of IL-1β and IL-6, TNF-α, and M1 profile than the control males. Immune dysregulation appeared to be different for both neurodevelopmental disorders in adolescence.

Family and developmental history of female versus male adolescents with ADHD: diagnosis-specific overlap, few gender/sex differences

Background

Gender and sex differences in the development of children and adolescents are commonly found in the psychiatric examination. Family and developmental history is an important part of the clinical diagnostic interview, the basic examination technique. Attention-deficit/hyperactivity disorder (ADHD) is associated with diagnosis-specific markers in family and development history. However, it is unclear to what extent ADHD-specific signs and narratives differ between females and males. The aim of this study was to assess and to compare the family and developmental history profiles of female versus male adolescents with ADHD.

Methods

Data were collected using the clinical diagnostic interview technique from parents of female and male patients diagnosed with ADHD (ICD-10  F90.0, F90.1 and F98.8) between the ages of 12 and 17  years (n = 92). The two groups were matched in pairs for sex, IQ and ICD-10 diagnosis (F90.0, F90.1 and F98.8). Interview data were operationalized in three categories: 0 - physiological marker, 1 - subclinical marker, 2 - clinical marker. The two groups were compared with two-way ANOVA.

Results

Information about female in comparison to male adolescents were reported in the parental interview with few differences.

Conclusion

Our study suggests that family and developmental history of the neurodevelopmental disorder ADHD is only poorly influenced by gender or sex.

Attention deficit hyperactivity disorder is associated with (a)symmetric tonic neck primitive reflexes: a systematic review and meta-analysis

Introduction

Investigation on the association between attention deficit hyperactivity disorder (ADHD) and primary reflexes is in the initial stage, with considerable differences in the findings. This study evaluated the association between ADHD and primitive reflexes using systematic review and meta-analysis.

Methods

Data were obtained from PubMed, Cochrane Library, Web of Science, EBSCO (Medical Literature Analysis and Retrieval System Online, American Psychological Association Psyclnfo, and Education Resources Information Center), Embase, Scopus, and ProQuest. Articles were searched from the date of inception of the respective databases to January 01, 2023, and StataCorp Stata (version 15) was used for the analysis.

Results

Four articles with 229 samples were included in the meta-analysis. Results showed a significant positive and moderate correlation between ADHD and primitive reflexes, particularly asymmetric tonic neck reflex: summary r value = 0.48, 95% CI = 0.27-0.64; symmetric tonic neck reflex: summary r value = 0.39, 95% CI = 0.25-0.52. Overall, findings from the sub-group analysis indicate that the behavioral problem measuring tool (Conners' scale), sex, and primitive reflex test could significantly moderate the relationships between ADHD and ATNR and STNR primitive reflexes.

Conclusion

ADHD symptoms in children are closely related to the non-integration of (a)symmetric tonic neck primitive reflexes. Longitudinal or experimental studies should be conducted to reveal the causal relationship between ADHD and primitive reflexes in the future.

Sex differences in conduct and emotional outcomes for young people with hyperactive/inattentive traits and social communication difficulties between 9 and 16 years of age: a growth curve analysis

BACKGROUND

The purpose of this paper is to identify the trajectory of conduct and emotional problems for young people within the general population at four time points (between 9 years 7 months and 16 years 6 months), investigate their relationship with hyperactive/inattentive traits and explore the moderating effect of autistic social traits (ASTs).

METHODS

Data from 9305 individuals involved in The Avon Longitudinal Study of Parents and Children (ALSPAC) study were included. Conduct and emotional problems and hyperactive/inattentive traits were measured by the Strengths and Difficulties Questionnaire. ASTs were assessed using the Social Communication Disorder Checklist. Individual trajectories for conduct and emotional problems were identified via growth curve modelling. Hyperactive/inattentive traits were included within the growth curve model as a time-varying covariate to determine their effect on these outcomes. Finally, participants were split into two groups (below and above clinical threshold ASTs Groups) and multi-group invariance testing was conducted on the data to identify the moderating effect of ASTs on the relationship between hyperactive/inattentive traits and outcomes (i.e. conduct and emotional problems).

RESULTS

Hyperactive/inattentive traits were associated with higher rates of conduct and emotional problems for both boys and girls. The presence of ASTs moderated these relationships for boys, but not for girls, by increasing the risk of boys with hyperactive/inattentive traits developing greater conduct and emotional problems.

CONCLUSIONS

These findings underscore the importance of identifying hyperactive/inattentive traits and ASTs in young people and addressing the increased risk of conduct and emotional problems. Research and clinical implications are explored.

Assessment of goal-directed behavior and prospective memory in adult ADHD with an online 3D videogame simulating everyday tasks

The diagnosis of ADHD is based on real-life attentional-executive deficits, but they are harder to detect in adults than in children and objective quantitative measures reflecting these everyday problems are lacking. We developed an online version of EPELI 3D videogame for naturalistic and scalable assessment of goal-directed action and prospective memory in adult ADHD. In EPELI, participants perform instructed everyday chores in a virtual apartment from memory. Our pre-registered hypothesis predicted weaker EPELI performances in adult ADHD compared to controls. The sample comprised 112 adults with ADHD and 255 neurotypical controls comparable in age (mean 31, SD = 8 years), gender distribution (71% females) and educational level. Using web-browser, the participants performed EPELI and other cognitive tasks, including Conner's Continuous Performance Test (CPT). They also filled out questionnaires probing everyday executive performance and kept a 5-day diary of everyday prospective memory errors. Self-reported strategy use in the EPELI game was also examined. The ADHD participants' self-ratings indicated clearly more everyday executive problems than in the controls. Differences in the EPELI game were mostly seen in the ADHD participants' higher rates of task-irrelevant actions. Gender differences and a group × gender interaction was found in the number of correctly performed tasks, indicating poorer performance particularly in ADHD males. Discriminant validity of EPELI was similar to CPT. Strategy use strongly predicted EPELI performance in both groups. The results demonstrate the feasibility of EPELI for online assessment and highlight the role of impulsivity as a distinctive everyday life problem in adult ADHD.

Sleep Architecture and EEG Power Spectrum Following Cumulative Sleep Restriction: A Comparison between Typically Developing Children and Children with ADHD

No studies have looked at the effects of cumulative sleep restriction (CSR) on sleep architecture or the power spectrum of sleep EEG (electroencephalogram) in school-age children, as recorded by PSG (polysomnography). This is true for both typically developing (TD) children and children with ADHD (attention deficit/hyperactivity disorder), who are known to have more sleep difficulties. Participants were children (ages 6-12 years), including 18 TD and 18 ADHD, who were age- and sex-matched. The CSR protocol included a two-week baseline and two randomized conditions: Typical (six nights of sleep based on baseline sleep schedules) and Restricted (one-hour reduction of baseline time in bed). This resulted in an average of 28 min per night difference in sleep. Based on ANOVAs (analysis of variance), children with ADHD took longer to reach N3 (non-rapid eye movement), had more WASO (wake after sleep onset) (within the first 5.1 h of the night), and had more REM (rapid eye movement) sleep than TD children regardless of condition. During CSR, ADHD participants had less REM and a trend toward longer durations of N1 and N2 compared to the TD group. No significant differences in the power spectrum were found between groups or conditions. In conclusion, this CSR protocol impacted some physiological aspects of sleep but may not be sufficient to cause changes in the power spectrum of sleep EEG. Although preliminary, group-by-condition interactions suggest that the homeostatic processes in children with ADHD may be impaired during CSR.

Short form Conners' Adult ADHD Rating Scales: Factor structure and measurement invariance by sex in emerging adults

INTRODUCTION

The short version of the Conners' Adult ADHD Rating Scales (CAARS-S:S) is a self-report measure used to identify symptoms of Attention Deficit/Hyperactivity Disorder (ADHD) during adulthood. However, its psychometric properties specifically in emerging adults, or the transitional age group between adolescence and adulthood, remain understudied. This study aimed to validate the factor structure of the CAARS-S:S in a sample of emerging adults.

METHOD

The CAARS-S:S measure was completed by adults (n = 591) aged 18 to 29 located in English-speaking countries, including Australia, Canada and the United States. Confirmatory factor analysis was used to test a four-factor model of Inattention/Memory Problems, Hyperactivity/Restlessness, Impulsivity/Emotional Lability and Problems with Self-Concept, as well as the model's invariance by sex. Sex was also included as a covariate in the model to examine differences in males' and females' scores on each factor.

RESULTS

Overall, the four-factor structure fit the data and was invariant across males and females. All factors demonstrated high internal reliability (average ωt and α = .86). It was observed that males tended to score higher on Inattention/Memory Problems while females scored higher on Problems with Self-Concept.

CONCLUSION

This research establishes the psychometric properties of the CAARS-S:S, placing greater confidence in using it to screen for ADHD symptoms in emerging adults living in a Westernized cultural context. The detailed findings of this research, implications for the use of the CAARS-S:S in this age group and potential future directions for examining the properties of the measure are discussed.

Necessity of an Integrative Animal Model for a Comprehensive Study of Attention-Deficit/Hyperactivity Disorder

Animal models of attention-deficit/hyperactivity disorder (ADHD) have been used to study and understand the behavioral, neural, and physiological mechanisms underlying ADHD. These models allow researchers to conduct controlled experiments and manipulate specific brain regions or neurotransmitter systems to investigate the underlying causes of ADHD and test potential drug targets or treatments. However, it is essential to note that while these models can provide valuable insights, they do not ideally mimic the complex and heterogeneous nature of ADHD and should be interpreted cautiously. Additionally, since ADHD is a multifactorial disorder, environmental and epigenetic factors should be considered simultaneously. In this review, the animal models of ADHD reported thus far are classified into genetic, pharmacological, and environmental models, and the limitations of the representative models are discussed. Furthermore, we provide insights into a more reliable alternative model for the comprehensive study of ADHD.

Sex-specific responses to juvenile stress on the dopaminergic system in an animal model of attention-deficit hyperactivity disorder

The etiology of attention-deficit hyperactivity disorder (ADHD) strongly suggests a genetic component as the main cause; however, environmental factors such as early adverse experiences in childhood may play an interactive role with the genetic susceptibility. Spontaneously hypertensive rats (SHRs), a genetic ADHD model, and control Wistar Kyoto rats (WKYs) were subjected to chronic unpredictable mild stress during the juvenile period. The behavioral characteristics were monitored, and dopamine-related factors in the core regions of dopaminergic pathways were measured. Higher ADHD symptom-related behaviors were observed in response to juvenile stress in male SHRs than control WKYs. For the SHRs subjected to juvenile stress, hyperactivity in males, recognition in females, and depressant potential in both sexes were markedly observed. In the expression of 17 dopamine-related genes and proteins, greater changes were detected in male SHRs subjected to juvenile stress, especially in dopamine metabolic factors. Dopamine clearance factors involved in dopamine degradation and transport, especially catechol-O-methyltransferase (COMT) and dopamine transporter (DAT), showed sex-specific differences induced by juvenile stress in dopamine metabolite assays. Moreover, stressed male SHRs treated with methylphenidate showed better improvement in behavior than the females, resulting in different levels of COMT and DAT amelioration. These results suggest that juvenile stress potentially increased the incidence of ADHD in a genetic rat model, which showed sex-specific differences based on the expression of COMT and DAT. Therefore, our results could help develop gender-specific diagnostics and healthcare options for juvenile stress in patients with ADHD.

Sex differences in medication-naïve adults with attention-deficit/hyperactivity disorder: a counting Stroop functional MRI study

Emerging evidence supports deficits in executive functions in the fronto-striato-parietal network in individuals with attention-deficit/hyperactivity disorder (ADHD). However, most functional studies recruited men with ADHD only, leaving it unclear whether executive deficits are also demonstrated in women with ADHD. Thus, we used functional magnetic resonance imaging to examine the sex differences in a counting Stroop task that explored interference control. The sample consisted of 55 medication-naïve adults with ADHD (28 men, 27 women) and 52 healthy controls (HC, 26 men, 26 women). The Conners' Continuous Performance Test further evaluated the performance of focused attention (standard deviation of the reaction time, RTSD) and vigilance (the reaction time change across different inter-stimulus intervals, RTISI). First, for the main effect of diagnosis, compared to the HC group, the ADHD group showed less activation in the caudate nucleus and inferior frontal gyrus (IFG). Second, for the main effect of sex, no significant effects were found. Third, a diagnosis-by-sex interaction indicated that the magnitude of ADHD-HC difference was greater for women than men in the right IFG and precuneus, reflecting greater difficulties for ADHD women to resolve interference. Conversely, no significant brain activation showed greater ADHD-HC difference in men than women. Also, reduced right IFG and precuneus activation was negatively associated with the scores assessing focused attention and vigilance in ADHD women, indicating that the attentional abilities are disrupted in ADHD women. Abnormalities in the frontoparietal areas may represent the main difference between ADHD women and ADHD men.

ADHD symptoms and diagnosis in adult preterms: systematic review, IPD meta-analysis, and register-linkage study

BACKGROUND

This study examined differences in ADHD symptoms and diagnosis between preterm and term-born adults (≥18 years), and tested if ADHD is related to gestational age, birth weight, multiple births, or neonatal complications in preterm borns.

METHODS

(1) A systematic review compared ADHD symptom self-reports and diagnosis between preterm and term-born adults published in PubMed, Web of Science, and PROQUEST until April 2021; (2) a one-stage Individual Participant Data(IPD) meta-analysis (n = 1385 preterm, n = 1633 term; born 1978-1995) examined differences in self-reported ADHD symptoms[age 18-36 years]; and (3) a population-based register-linkage study of all live births in Finland (01/01/1987-31/12/1998; n = 37538 preterm, n = 691,616 term) examined ADHD diagnosis risk in adulthood (≥18 years) until 31/12/2016.

RESULTS

Systematic review results were conflicting. In the IPD meta-analysis, ADHD symptoms levels were similar across groups (mean z-score difference 0.00;95% confidence interval [95% CI] -0.07, 0.07). Whereas in the register-linkage study, adults born preterm had a higher relative risk (RR) for ADHD diagnosis compared to term controls (RR = 1.26, 95% CI 1.12, 1.41, p < 0.001). Among preterms, as gestation length (RR = 0.93, 95% CI 0.89, 0.97, p < 0.001) and SD birth weight z-score (RR = 0.88, 95% CI 0.80, 0.97, p < 0.001) increased, ADHD risk decreased.

CONCLUSIONS

While preterm adults may not report higher levels of ADHD symptoms, their risk of ADHD diagnosis in adulthood is higher.

IMPACT

Preterm-born adults do not self-report higher levels of ADHD symptoms, yet are more likely to receive an ADHD diagnosis in adulthood compared to term-borns. Previous evidence has consisted of limited sample sizes of adults and used different methods with inconsistent findings. This study assessed adult self-reported symptoms across 8 harmonized cohorts and contrasted the findings with diagnosed ADHD in a population-based register-linkage study. Preterm-born adults may not self-report increased ADHD symptoms. However, they have a higher risk of ADHD diagnosis, warranting preventive strategies and interventions to reduce the presentation of more severe ADHD symptomatology in adulthood.

Sex and gender in neurodevelopmental conditions

Health-related conditions often differ qualitatively or quantitatively between individuals of different birth-assigned sexes and gender identities, and/or with different gendered experiences, requiring tailored care. Studying the moderating and mediating effects of sex-related and gender-related factors on impairment, disability, wellbeing and health is of paramount importance especially for neurodivergent individuals, who are diagnosed with neurodevelopmental conditions with uneven sex/gender distributions. Researchers have become aware of the myriad influences that sex-related and gender-related variables have on the manifestations of neurodevelopmental conditions, and contemporary work has begun to investigate the mechanisms through which these effects are mediated. Here we describe topical concepts of sex and gender science, summarize current knowledge, and discuss research and clinical challenges related to autism, attention-deficit/hyperactivity disorder and other neurodevelopmental conditions. We consider sex and gender in the context of epidemiology, behavioural phenotypes, neurobiology, genetics, endocrinology and neighbouring disciplines. The available evidence supports the view that sex and gender are important contributors to the biological and behavioural variability in neurodevelopmental conditions. Methodological caveats such as frequent conflation of sex and gender constructs, inappropriate measurement of these constructs and under-representation of specific demographic groups (for example, female and gender minority individuals and people with intellectual disabilities) limit the translational potential of research so far. Future research and clinical implementation should integrate sex and gender into next-generation diagnostics, mechanistic investigations and support practices.

Labour market marginalisation in young adults diagnosed with attention-deficit hyperactivity disorder (ADHD): a population-based longitudinal cohort study in Sweden

BACKGROUND

The objective of this population-based register study was (1) to investigate the association between young adults diagnosed with attention-deficit/hyperactivity disorder (ADHD) and subsequent labour market marginalisation (LMM) in two comparison groups, i.e. matched young adults from the general population without ADHD and unaffected siblings to persons with ADHD and (2) to assess the role of comorbid disorders.

METHODS

This study included all young adults in Sweden, aged 19-29 years, with an incident diagnosis of ADHD 2006-2011 (n = 9718). Crude and multivariate sex-stratified hazard ratios (HRs) with 95% confidence intervals (CIs) were measured 5 years after the diagnosis of ADHD for the risk of disability pension, long-term sickness absence (SA) (>90 days), long-term unemployment (>180 days) and a combined measure of all three in young adults with ADHD compared to their siblings without ADHD and a matched comparison group.

RESULTS

In the adjusted analyses young adults with ADHD had a 10-fold higher risk of disability pension (HR = 10.2; CI 9.3-11.2), a nearly three-fold higher risk of long-term SA (HR = 2.7; CI 2.5-2.8) and a 70% higher risk of long-term unemployment (HR = 1.7; CI 1.6-1.8) compared to the matched comparison group. The risk estimates were lower compared to siblings for disability pension (HR = 9.0; CI 6.6-12.3) and long-term SA (HR = 2.5; CI 2.1-3.1) but higher in the long-term unemployed (HR = 1.9; CI 1.6-2.1). Comorbid disorders explained about one-third of the association between ADHD and disability pension, but less regarding SA and long-term unemployment.

CONCLUSIONS

Young adults with ADHD have a high risk for different measures of LMM and comorbidities explain only a small proportion of this relationship.

Systematic Review of Gender-Specific Child and Adolescent Mental Health Care

Gender differences in mental health emerge as early as in childhood and adolescence, highlighting the potential need for gender-specific child and adolescent mental health care. However, it is unclear how gender-specific child and adolescent mental health care is implemented and whether its' approaches are useful. Therefore, this study reviews gender-specific interventions and their effectiveness for child and adolescent mental health. Five databases were searched for articles published between 2000 and 2021. In total, 43 studies were included. Most interventions were conducted in school (n = 15) or community settings (n = 8). Substance-related disorders (n = 13) and eating disorders (n = 12) were addressed most frequently. Most interventions targeted girls (n = 31). Various gender-specific aspects were considered, including gender-specific risk and protective factors (n = 35) and needs (n = 35). Although most interventions yielded significant improvements in mental health outcomes (n = 32), only few studies reported medium or large effect sizes (n = 13). Additionally, there was a lack of strong causal evidence derived from randomized controlled trials, calling for more rigorous trials in the research field. Nevertheless, our findings indicate that gender-specific mental health care can be a promising approach to meet gender-specific mental health needs.

Association of Childhood Externalizing, Internalizing, and Comorbid Symptoms With Long-term Economic and Social Outcomes

IMPORTANCE

Little is known about the long-term economic and social outcomes for children with longitudinally assessed comorbid externalizing and internalizing symptoms, especially compared with children with externalizing symptoms or internalizing symptoms only.

OBJECTIVE

To examine the association between childhood trajectories of externalizing, internalizing, and comorbid symptoms and long-term economic and social outcomes.

DESIGN, SETTING, AND PARTICIPANTS

A 32-year prospective cohort study linked with administrative data was conducted in school-aged participants aged 6 to 12 years in the Québec Longitudinal Study of Kindergarten Children (N = 3017) followed up from 1985 to 2017. Data analysis was conducted between August 1, 2021, and March 31, 2022.

EXPOSURES

Teacher-rated behavioral symptoms were used to categorize children from age 6 to 12 years into developmental profiles using group-based trajectory modeling.

MAIN OUTCOMES AND MEASURES

Multivariable regression models were used to test the association between childhood symptom profile group and adult employment earnings, welfare receipt, intimate partnership status, and having children living in the household. Participant sex, IQ, and socioeconomic background were adjusted for.

RESULTS

Of 3017 participants in this sample, 1594 (52.8%) were male and 1423 (47.2%) were female. Per confidentiality rules established by Statistics Canada, income variables were rounded to base 100 and count variables were rounded to base 10; the mean (SD) age was 37 (0.29) years at follow-up. Four symptom profiles were identified: no/low (n = 1369 [45.4%]), high externalizing (882 [29.2%]), high internalizing (354 [11.7%]), and comorbid (412 [13.7%]) symptoms. Compared with the no/low symptom profile, participants in the high externalizing-only profile earned $5904 (95% CI, -$7988 to -$3821) less per year and had 2.0 (95% CI, 1.58-2.53) times higher incidence of welfare receipt, while participants in the high internalizing group earned $8473 (95% CI, -$11 228 to -$5717) less per year, had a 2.07 (95% CI, 1.51-2.83) higher incidence of welfare receipt, and had a lower incidence of intimate partnership (incident rate ratio [IRR], 0.89; 95% CI, 0.80-0.99). Participants in the comorbid profile fared especially poorly: they earned $15 031 (95% CI, -$18 030 to -$12 031) less per year, had a 3.79 (95% CI, 2.75-5.23) times higher incidence of annual welfare receipt, and were less likely to have an intimate partner (IRR, 0.71; 95% CI, 0.63-0.79) and children living in the household (IRR, 0.86; 95% CI, 0.80-0.92). Estimated lost earnings over a 40-year working career were $140 515 for the high externalizing, $201 657 for the high internalizing, and $357 737 for the comorbid profiles.

CONCLUSIONS AND RELEVANCE

In this cohort study, children exhibiting sustained childhood high externalizing, high internalizing, or comorbid symptoms were at increased risk of poor economic and social outcomes into middle age. These findings suggest that children exhibiting comorbid problems were especially vulnerable and that early detection and support are indicated.