ADHD and female specific concerns: a review of the literature and clinical implications

Attention-deficit/hyperactivity disorder in children with epilepsy: A systematic review and meta-analysis of prevalence and risk factors

OBJECTIVE

To evaluate the prevalence of and risk factors for attention-deficit/hyperactivity disorder (ADHD) in children with epilepsy (CWE).

METHODS

We conducted a systematic search in PubMed and Embase for the meta-analysis. The pooled prevalence of ADHD was calculated using a random-effects model; subgroup analyses were performed to explore heterogeneity. We collected raw data from articles reporting potential risk factors, which were included in the subsequent risk factor analysis.

RESULTS

Forty-six articles met the inclusion criteria for the meta-analysis, which showed a pooled ADHD prevalence of 30.7% in CWE, with a predominance of the inattentive subtype of ADHD; the heterogeneity of prevalence was related to population source/study setting (clinic based, community based, or database based) and method of ADHD diagnosis (with or without clinical review). Risk factors for ADHD in epilepsy included younger age, intellectual/developmental disabilities, a family history of epilepsy, earlier epilepsy onset, absence epilepsy, more frequent seizures, and polytherapy; In contrast, risk factors such as sex, generalized epilepsy or seizures, epilepsy etiology, and electroencephalogram abnormalities were not significantly associated with the occurrence of ADHD.

SIGNIFICANCE

The prevalence of ADHD in CWE is high and several potential risk factors are associated with it. This study contributes to a better understanding of ADHD in epilepsy for screening and treatment.

PLAIN LANGUAGE SUMMARY

This systematic review summarizes the prevalence of attention-deficit/hyperactivity disorder (ADHD) occurring in children with epilepsy and analyses the risk factors for comorbid ADHD in epilepsy. By reviewing 46 articles, we concluded that the overall prevalence of ADHD in children with epilepsy was 30.7% and that intellectual/developmental disabilities were the most significant risk factor for combined ADHD in children with epilepsy. This study provides a wealth of information on comorbid ADHD in epilepsy, which will help clinicians identify and treat potential ADHD in children with epilepsy in a timely manner.

Diversity and representation in ADHD psychosocial treatment research: A comprehensive synthesis with data from over 10,000 participants

Demographic data from nearly 50 years of treatment research for children and adolescents with attention-deficit/hyperactivity disorder (ADHD) are synthesized. Comprehensive search identified ADHD treatment studies that were between-group designs, included a psychosocial, evidence-based treatment, and were conducted in the United States. One hundred and twenty-six studies that included 10,604 youth were examined. Reporting of demographics varied with 48% of studies (k = 61) reporting ethnicity, 73% (k = 92) reporting race, 80% (k = 101) reporting age (M age = 8.81, SD = 2.82), and 88% (k = 111) reporting gender. Most participants identified as non-Hispanic/Latine (15.99% Hispanic/Latine), White (62.54%), and boys (74.39%; 24.47% girls). Since the 1970s, zero youth in ADHD treatment studies identified as Middle Eastern/North African, 0.1% were American Indian/Alaskan Native or Native Hawaiian Pacific Islander, 1.77% were Asian, 15.10% were Black, and 3.14% were Multiracial. Based on publication year, the proportions of girls, racially minoritized youth, and Hispanic/Latine youth included in ADHD treatment research have increased over time. Girls, non-binary and non-cisgender youth, young children, adolescents, Hispanic/Latine youth, and youth from all racial groups other than White are underrepresented in ADHD treatment research. Research gaps are discussed, and recommendations for comprehensive demographic reporting in child and adolescent psychological research are provided.

The Impact of Sex on Cognitive Control in ADHD: Girls Slow to Inhibit, Boys Inhibit Less, and Both Show Higher Response Variability

OBJECTIVE

To determine whether girls and boys with ADHD show distinct impairments in components of cognitive control across multiple tasks (go/no-go, stop signal, and flanker) and performance metrics (response speed, variability, and errors).

METHOD

A total of 300 children, ages 8 to 12 years with ADHD (n = 210, 58 girls) or typically developing (TD; n = 99, 37 girls), completed all tasks. Traditional response measures (e.g., mean and standard deviation of reaction time, inhibition errors, and stop signal reaction time) and ex-Gaussian modeling of reaction times (mu, sigma, and tau) were analyzed.

RESULTS

Girls showed intact response inhibition in the context of slower response speed, while boys made more inhibition errors and did not slow their response speed. Both girls and boys with ADHD showed higher response variability and poorer interference control than TD children.

CONCLUSION

Girls and boys with ADHD show distinct impairments in cognitive control that may be important for understanding the pathophysiology of ADHD.

Longitudinal study on all-cause and suicide mortality among individuals with attention deficit hyperactivity disorder

BACKGROUND

Previous research has linked attention deficit hyperactivity disorder (ADHD) with an increased risk of all-cause mortality, primarily owing to unnatural causes such as accidents and suicides. This increase may be attributable to the co-occurrence of major psychiatric disorders, including schizophrenia (SCZ), bipolar disorder (BD), major depressive disorder (MDD), autism spectrum disorder (ASD), anxiety disorders, substance use disorders (SUDs), and personality disorders (PDs). This study examined the all-cause and specific-cause mortality rates in individuals with ADHD and the influence of psychiatric comorbidities.

METHODS

Between 2003 and 2017, 1.17 million individuals were enrolled in the study, of which 233,886 received a diagnosis of ADHD from the Taiwan's National Health Insurance Research Database. A 1:4 sex- and birth year-matched control group without ADHD was also included. Hazard ratios (HRs) for mortality rates were estimated between groups after adjusting for demographic data.

RESULTS

During the follow-up period, 781 individuals with ADHD died. The HR for all-cause mortality was 1.45 (95% confidence interval [CI]: 1.30-1.61), largely owing to unnatural causes, particularly suicide. Suicide rates were particularly high in individuals with ADHD and psychiatric comorbidities: the HRs for suicide were 47.06 in ADHD with SUDs (95% CI: 6.12-361.99), 32.02 in ADHD with SCZ (7.99-128.29), 23.60 in ADHD with PDs (7.27-76.66), 10.11 in ADHD with anxiety disorders (5.74-17.82), 9.30 in ADHD with BD (4.48-19.33), 8.36 in ADHD with MDD (5.66-12.35), and 6.42 in ADHD with ASD (1.83-22.53) relative to ADHD only.

DISCUSSION

ADHD was associated with increased mortality rates, primarily owing to suicide. The presence of major psychiatric comorbidities was associated with a further increase in suicide mortality risk.

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.

Object Recognition Memory Deficits in ADHD: A Meta-analysis

Object recognition memory allows us to identify previously seen objects. This type of declarative memory is a primary process for learning. Despite its crucial role in everyday life, object recognition has received far less attention in ADHD research compared to verbal recognition memory. In addition to the existence of a small number of published studies, the results have been inconsistent, possibly due to the diversity of tasks used to assess recognition memory. In the present meta-analysis, we have collected studies from Web of Science, Scopus, PubMed, and Google Scholar databases up to May 2023. We have compiled studies that assessed visual object recognition memory with specific visual recognition tests (sample-match delayed tasks) in children and adolescents diagnosed with ADHD. A total of 28 studies with 1619 participants diagnosed with ADHD were included. The studies were assessed for risk of bias using the Quadas-2 tool and for each study, Cohen's d was calculated to estimate the magnitude of the difference in performance between groups. As a main result, we have found a worse recognition memory performance in ADHD participants when compared to their matched controls (overall Cohen's d ~ 0.492). We also observed greater heterogeneity in the magnitude of this deficit among medicated participants compared to non-medicated individuals, as well as a smaller deficit in studies with a higher proportion of female participants. The magnitude of the object recognition memory impairment in ADHD also seems to depend on the assessment method used.

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.

A Female-Specific Treatment Group for ADHD-Description of the Programme and Qualitative Analysis of First Experiences

Background: The diagnostics and treatment of attention-deficit/hyperactivity disorder (ADHD) in women remain insufficient. Fluctuations of reproductive hormones during the premenstrual period, postpartum period, and (peri)menopause are neglected, even though they impact ADHD symptoms and associated mood disorders. Therefore, we created a female-specific treatment group for women with ADHD and premenstrual worsening of ADHD and/or mood symptoms. Methods: We describe the group programme and underlying rationale, offering a qualitative analysis of the participants' evaluation. Results: The seven bi-weekly sessions foreground the menstrual cycle and address several ADHD-specific topics in relation to this cyclical pattern. Concurrently, women track their menstrual cycle and (fluctuating) ADHD and mood symptoms with an adjusted premenstrual calendar. In total, 18 women (25-47 years) participated in three consecutive groups. We analysed the evaluation of the last group. Participants experienced the group as a safe and welcoming space. Recognition was valued by all. The topics discussed were deemed valuable, and the structure suited them well. Completing the premenstrual calendar augmented the awareness and recognition of individual cyclical symptoms. A lifespan approach increased self-understanding. Participants took their menstrual cycle more seriously, prioritising self-acceptance and self-care. Conclusions: Exploring a cyclical approach in a group setting seems to be a positive addition to treatment for female ADHD.

Coming to Terms with Our Racecar Brains: Academic Mothers Experiencing Adult Diagnosis of ADHD

This collaborative autoethnography explores the experiences of women academics and mothers who received late diagnoses of Attention Deficit Hyperactivity Disorder (ADHD). Due to the historical underdiagnosis of women, little research has focused on this specific demographic. We shed light on how ADHD presents in women, interweaving our stories with extant literature and emphasizing the need to understand this demographic's experiences better. This piece discusses our process of seeking diagnosis and treatment, the communicative disenfranchisement we faced, and the stigma associated with ADHD. Our narratives highlight the generational impact of ADHD, with family members often sharing our diagnosis. Through divulging our experiences, we hope to contribute to the destigmatization of ADHD, particularly for women and academics.

Impaired segregation of the attention deficit hyperactivity disorder related pattern in children

BACKGROUND

Inattention is a key characteristic of attention deficit hyperactivity disorder (ADHD). Specific brain abnormalities associated with this symptom form a discernible pattern related with ADHD in children (i.e., ADHD related pattern) in our earlier research. The developmental processes of segregation and integration may be crucial to ADHD. However, how brains reconfigure these processes of the ADHD related pattern in different subtypes of ADHD and across sexes remain unclear.

METHODS

Nested-spectral partition method was applied to identify effects of subtype and sex on segregation and integration of the ADHD related pattern, using 145 ADHD patients and 135 typically developing controls (TDC) aged 7-14. Relationships between the measures and inattention symptoms were also investigated.

RESULTS

Children with ADHD exhibited lower segregation of the ADHD related pattern (p = 1.17 × 10-8) than TDCs. Only the main effect of subtype was significant (p = 1.14 × 10-5). Both ADHD-C (p = 2.16 × 10-6) and ADHD-I (p = 2.87 × 10-6) patients had lower segregation components relative to the TDC. Moreover, segregation components were negatively correlated with inattention scores.

CONCLUSIONS

This study identified impaired segregation in the ADHD related pattern of children with ADHD and found shared neural bases among different subtypes and sexes.

Female-specific pharmacotherapy in ADHD: premenstrual adjustment of psychostimulant dosage

Objective

Attention-Deficit/Hyperactivity Disorder (ADHD) is a common neurodevelopmental condition which is underdiagnosed and undertreated in women. For decades, the ADHD field has called for more insight into female-specific therapy. Preliminary findings postulate that changes in sex hormones during the menstrual cycle may influence the effectiveness of psychostimulant medication. Yet, pharmacotherapeutic interventions tailored to women with ADHD remain scarce. Previously, our group showed an increase in mood symptoms in the premenstrual week in women with ADHD. Premenstrual worsening of depressive and ADHD symptoms represent a treatment challenge. In our adult ADHD clinic, we noted several women describing exacerbation of their ADHD and depressive symptoms in the premenstrual week and/or insufficient effect of their established dosage of psychostimulant. We responded to the need expressed by these women by increasing their stimulant dosage in the premenstrual week, while monitoring the response and side effects.

Methods

This community case study of nine consecutive women being treated for ADHD and co-occurring conditions (including depression and premenstrual dysphoric disorder), reports our local experience of increasing the individually prescribed psychostimulant dosage during the premenstrual period. We methodically monitored the effect of this increased dosage on ADHD symptoms, mood and somatic symptoms for the following 6-24 months.

Results

With premenstrual dose elevation, all nine women experienced improved ADHD and mood symptoms with minimal adverse events. Premenstrual inattention, irritability and energy levels improved, and now resembled the other non-premenstrual weeks more closely. All women decided to continue with the elevated premenstrual pharmacotherapy.

Discussion

Our preliminary results demonstrate potential benefits of increasing premenstrual psychostimulant dosage in women with ADHD, experiencing premenstrual worsening of ADHD and mood symptoms. The results concur with previous findings of diminished response to amphetamines in the late luteal phase. Increased dosage may help combat premenstrual worsening of cognitive and emotional symptoms in women with ADHD, with significant clinical implications. Better management of premenstrual ADHD and mood symptoms in vulnerable women can improve treatment outcome and meet an unmet need. However, implementation should be individually explored. Further investigation of luteal phase psychostimulant dose adjustment is required for safe, optimal and individualised treatment for women with ADHD.

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.

"Dysregulated not deficit": A qualitative study on symptomatology of ADHD in young adults

OBJECTIVE

Attention-deficit/hyperactivity disorder (ADHD) is a common condition that often persists into adulthood, although data suggest that the current diagnostic criteria may not represent how the condition presents in adults. We aimed to use qualitative methods to better understand ADHD symptomatology in young adults, especially regarding attentional and emotional dysregulation.

METHODS

Nine focus groups involving young adults (aged 18-35 years; N = 43; 84% female; 86% US and Canada) with diagnoses of ADHD were conducted. Participants were asked about their perceptions of the current diagnostic criteria and how their symptoms have presented and changed over time. Data were analyzed using an interpretive phenomenological analysis framework.

RESULTS

Most participants reported that the diagnostic criteria did not accurately capture their experiences with ADHD. They reported struggling with attention dysregulation, including hyperfocusing, and emotional dysregulation, including rejection-sensitive dysphoria. Many participants believed that their changing environments and behavioral adaptations influenced how their symptoms presented into adulthood.

CONCLUSION

Current diagnostic criteria for ADHD may not capture the range of symptoms present in young adults. More research is needed to characterize attentional and emotional dysregulation in this population.

Silver linings of ADHD: a thematic analysis of adults' positive experiences with living with ADHD

OBJECTIVES

To identify and explore positive aspects of attention deficit hyperactivity disorder (ADHD) as reported by adults with the diagnosis.

DESIGN

The current study used a qualitative survey design including the written responses to an open-ended question on positive aspects of ADHD. The participants' responses were analysed using thematic analysis.

SETTING

The participants took part in trial of a self-guided internet-delivered intervention in Norway. As part of the intervention, the participants were asked to describe positive aspects of having ADHD.

PARTICIPANTS

The study included 50 help-seeking adults with an ADHD diagnosis.

RESULTS

The participants described a variety of positive aspects related to having ADHD. The participants' experiences were conceptualised and thematically organised into four main themes: (1) the dual impact of ADHD characteristics; (2) the unconventional mind; (3) the pursuit of new experiences and (4) resilience and growth.

CONCLUSIONS

Having ADHD was experienced as both challenging and beneficial, depending on the context and one's sociocultural environment. The findings provide arguments for putting a stronger emphasis on positive aspects of ADHD, alongside the challenges, in treatment settings.

TRIAL REGISTRATION NUMBER

NCT04511169.

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.

Gait in children with and without ADHD: A systematic literature review

BACKGROUND

There is increasing speculation whether Attention-Deficit/Hyperactivity Disorder (ADHD) has phenotypic or secondary motor symptoms. Some evidence suggests even fundamental motor skills such as walking can differ in ADHD, however, the evidence is limited and has not been reviewed. Therefore, we conducted a systematic review to summarize the findings regarding gait in ADHD compared to typically developing children in (1) normal (i.e., self-paced), (2) paced or complex (i.e., walking backwards), and (3) dual-task contexts.

METHOD

Following a thorough literature search and application of stringent exclusion criteria, a total of 12 studies were included in this review. All studies examined normal walking with a variety of gait parameters in children (age range: 5-18), however, selected parameters and group differences were often inconsistent.

RESULTS

In self-paced walking, studies reporting gait with coefficients of variance (CVs) indicated several between-group differences, whereas averages of gait variables were the same for those with ADHD and typically developing children. Paced or complex walking contexts often differed between ADHD and typically developing groups, favoring the ADHD group in some cases, but primarily the typically developing participants. Finally, walking contexts with dual-tasks showed more frequent performance losses in the ADHD group.

DISCUSSION

Children with ADHD seem to have specific patterns of gait variability compared to typically developing children, particularly in complex walking contexts and at faster paces. The influence of age, medication, and method of gait normalization may have influenced the results of studies. Overall, this review highlights the potential for a unique gait profile in children with ADHD.

Effects of methylphenidate on impulsive choice and delay aversion in Lewis rats

Attention-deficit/hyperactivity disorder (ADHD), a common behavioral disorder in children and young adults, is characterized by symptoms of impulsivity, inattention, and hyperactivity. The purpose of this study was to evaluate the Lewis rat strain as a model of ADHD by testing their impulsive choices. Lewis rats were compared to their source strain, the Wistar rat, on an impulsive choice task. Rats completed the tasks on and off methylphenidate, a commonly prescribed medication for ADHD. Off methylphenidate, Lewis rats made more impulsive choices than Wistar rats. Analyses of acquisition of choice behavior suggested that both strains were able to discriminate reward sizes, but Lewis rats still chose the smaller-sooner option more than the larger-later (LL) option when the delays to reward were the same. This may be due to an aversion to the LL lever, which was associated with the longest delays to reward. Higher doses of methylphenidate increased LL choices in Lewis rats but decreased LL choices in Wistar rats. Altogether, these results suggest Lewis rats may be a viable model for ADHD in individuals whose symptoms are characterized by impulsive choices.

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.

Girls With Social and/or Attention Deficit Re-Examined in Young Adulthood: Prospective Study of Diagnostic Stability, Daily Life Functioning and Social Situation

OBJECTIVE

Investigate diagnostic stability, daily life functioning and social situation in women diagnosed with ADHD and/or ASD in childhood.

METHODS

Prospective 17 to 20-year follow-up study of 100 girls of whom 92 diagnosed in childhood with main DSM-IV ADHD or ASD, and 60 comparison girls. Ninety and 54 of these women were examined (M = 27, 4 years old) with semi-structured interviews and questionnaires, close relatives were interviewed.

RESULTS

At follow-up, 89% of women with ADHD or ASD in childhood still met the criteria for either of these diagnoses. Very few women were "in remission." In 34% the main diagnosis shifted from ADHD to ASD. Women with ADHD and ASD had significantly more disability and unfavorable social situation than comparison women.

CONCLUSION

Women with ADHD and/or ASD in childhood had impairing problems 17 to 20 years later. Early ADHD changed to ASD in adulthood in some cases. Nearly all with ASD met criteria for ADHD as adults.

Rare copy number variants in males and females with childhood attention-deficit/hyperactivity disorder

While childhood attention-deficit/hyperactivity disorder (ADHD) is more prevalent in males than females, genetic contributors to this effect have not been established. Here, we explore sex differences in the contribution of common and/or rare genetic variants to ADHD. Participants were from the Adolescent Brain and Cognitive Development study (N = 1253 youth meeting DSM-5 criteria for ADHD [mean age = 11.46 years [SD = 0.87]; 31% female] and 5577 unaffected individuals [mean age = 11.42 years [SD = 0.89]; 50% female], overall 66% White, non-Hispanic (WNH), 19% Black/African American, and 15% other races. Logistic regression tested for interactions between sex (defined genotypically) and both rare copy number variants (CNV) and polygenic (common variant) risk in association with ADHD. There was a significant interaction between sex and the presence of a CNV deletion larger than 200 kb, both in the entire cohort (β = -0.74, CI = [-1.27 to -0.20], FDR-corrected p = 0.048) and, at nominal significance levels in the WNH ancestry subcohort (β = -0.86, CI = [-1.51 to -0.20], p = 0.010). Additionally, the number of deleted genes interacted with sex in association with ADHD (whole cohort. β = -0.13, CI = [-0.23 to -0.029], FDR-corrected p = 0.048; WNH. β = -0.17, CI = [-0.29 to -0.050], FDR-corrected p = 0.044) as did the total length of CNV deletions (whole cohort. β = -0.12, CI = [-0.19 to -0.044], FDR-corrected p = 0.028; WNH. β = -0.17, CI = [-0.28 to -0.061], FDR-corrected p = 0.034). This sex effect was driven by increased odds of childhood ADHD for females but not males in the presence of CNV deletions. No similar sex effect was found for CNV duplications or polygenic risk scores. The association between CNV deletions and ADHD was partially mediated by measures of cognitive flexibility. In summary, CNV deletions were associated with increased odds for childhood ADHD in females, but not males.

Inhibitory Control Training Improves Attention Deficit-Hyperactivity Disorder Symptoms and Externalizing Behavior

BACKGROUND

Based on dysexecutive function theory of Attention deficit-hyperactivity disorder (ADHD), inhibitory control plays a crucial role in ADHD symptoms and respective behavioral problems.

METHODS

In the present study, 30 preschoolers with ADHD were recruited in a random clinical trial design in two control and intervention groups. The Flanker and Go/No-Go tasks, Swanson, Nolan, and Pelham Rating Scale, and Child Behavior Checklist were used for assessment at baseline, after the intervention, and 1-month follow-up sessions. The program for attentive rehabilitation of inhibition and selective attention (PARISA) was used for intervention in 10-12 sessions.

RESULTS

Findings showed an improvement in prepotent inhibition and interference control in the intervention group. Furthermore, the hyperactivity/impulsivity symptoms were ameliorated, and the externalizing behavioral problems were improved after the intervention.

CONCLUSION

Inhibitory control in preschoolers with ADHD is trainable, and the training gain could be transferred to ADHD symptoms and externalizing behavior.

Gender-based differences in prevalence and effects of ADHD in adults: A systematic review

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder that starts from childhood and lasts through adulthood. Historically thought as male dominant disorder, researches now emphasized that ADHD also effects females equally. Despite the ascending research on gender differences of ADHD, there is little known about its differences in prevalence and effects and there is a dearth of reviews that can draw a firm conclusion especially in adults. Data from the available medical literature published in English language literature of all time was reviewed systematically and tabulated to evaluate the gender-based differences in prevalence and effects of ADHD in adults. The studies revealed gender differences in adult ADHD in prevalence, and effects. Results showed that males have more prevalence as compared to females but females too have a significant presence of disorder. Females were more impaired as compared to men in most of the effects of ADHD like social functioning, time perception, stress tackling and mood disorder. Males were more impaired in working memory and educational functioning as compared to females. The review shows sufficient evidence of gender differences in adult ADHD in prevalence, and effects, that similarity across genders should not be assumed. It is concluded that there are plenty of conflicting evidence regarding gender differences in many areas of adult ADHD research, and to remove such discrepancies, the existing research is the need for more studies on gender differences and similarities in functioning of adults with ADHD.

Factors Influencing Post-Stroke Cognitive Impairment in Patients with Type 2 Diabetes Mellitus

Objective

Type 2 diabetes mellitus (T2DM) and ischemic stroke, which are common diseases among older people, are closely related to cognitive impairment. This study aims to investigate the influencing factors of post-stroke cognitive impairment (PSCI) in patients with T2DM.

Methods

We enrolled 161 patients with T2DM who experienced acute ischemic stroke and were hospitalized in the Department of Neurology, Jinan Central Hospital, Shandong, China. Cognitive function was evaluated with the Montreal Cognitive Assessment scale. According to the results, patients were divided into three groups-the cognitively normal group, mild cognitive impairment group, and severe cognitive impairment group. We analyzed general demographic data, laboratory information, imaging data, the results of neuropsychological evaluation, and clinical features as well as influencing factors of PSCI in these patients and established a prediction model.

Results

The three groups of patients were significantly different in terms of age, education level, course of diabetes mellitus (DM), recurrent cerebral infarction (RCI), and other factors. RCI, course of DM, and glycated hemoglobin (HbA1c) were independent risk factors of PSCI in patients with T2DM, with odds ratio (95% confidence interval): 7.17 (2.09, 30.37), 5.39 (2.40, 14.59), and 3.89 (1.66, 10.04), respectively, whereas female, senior high school, serum albumin were protective factors: 0.28 (0.07, 0.95), 0.05 (0.01, 0.21), 0.20 (0.08, 0.42), respectively. Furthermore, we constructed a prediction model using sex, age, education level, RCI, DM course, HbA1c and serum albumin and obtained a receiver operating characteristic (ROC) curve. The area under the ROC curve is 0.966, suggesting the significant association of these influencing factors with PSCI in patients with T2DM.

Conclusion

In this study, the occurrence of PSCI in patients with T2DM was related to RCI, course of DM, and HbA1c, among other factors. Attention to influencing factors is needed in these patients for early diagnosis and timely intervention of cognitive impairment.

Sex Differences in Substance Use, Prevalence, Pharmacological Therapy, and Mental Health in Adolescents with Attention-Deficit/Hyperactivity Disorder (ADHD)

Sex differences are poorly studied within the field of mental health, even though there is evidence of disparities (with respect to brain anatomy, activation patterns, and neurochemistry, etc.) that can significantly influence the etiology and course of mental disorders. The objective of this work was to review sex differences in adolescents (aged 13–18 years) diagnosed with ADHD (according to the DSM-IV, DSM-IV-TR and DSM-5 criteria) in terms of substance use disorder (SUD), prevalence, pharmacological therapy and mental health. We searched three academic databases (PubMed, Web of Science, and Scopus) and performed a narrative review of a total of 21 articles. The main conclusions of this research were (1) girls with ADHD are more at risk of substance use than boys, although there was no consensus on the prevalence of dual disorders; (2) girls are less frequently treated because of underdiagnosis and because they are more often inattentive and thereby show less disruptive behavior; (3) together with increased impairment in cognitive and executive functioning in girls, the aforementioned could be related to greater substance use and poorer functioning, especially in terms of more self-injurious behavior; and (4) early diagnosis and treatment of ADHD, especially in adolescent girls, is essential to prevent early substance use, the development of SUD, and suicidal behavior.

Clustering of social disadvantage with attention-deficit/hyperactivity disorder in young adults: A register-based study in Sweden

The clustering of social disadvantage with attention‐deficit/hyperactivity disorder (ADHD) in young adulthood is not well understood. We examined the clustering of ADHD with low educational attainment and unemployment in young adulthood; whether such clustering is stronger when unemployment is prolonged; and whether further clustering of disability pensioning, low education and unemployment occurs among those with ADHD. Data were obtained from Swedish health, demographic and social security registers from which 8,990 individuals with recorded ADHD diagnoses at the age of 10–35 and their 44,387 matched referents without mental disorders. Social disadvantage was measured using data on educational attainment, unemployment and disability pension from the diagnosis year or age 19 if diagnosed at younger age. Clustering was examined by comparing observed and expected occurrence (O/E ratio) of all possible combinations of ADHD, low education and unemployment, and, among those with ADHD, additional combinations with new‐onset disability pension. The likelihood of having neither ADHD, low education nor unemployment was increased (O/E ratio = 1.20, 95% confidence interval 1.19–1.20 at baseline; 1.18, 1.17–1.18 at follow‐up), as well as having all three characteristics (O/E ratio = 3.99, 3.89–4.10 at baseline; 5.68, 5.47–5.89 at follow‐up). This clustering was stronger among women than men and when unemployment was prolonged. The results suggest that low education and unemployment appear to cluster remarkably with ADHD among young adults, more so among women and when unemployment is prolonged.

Annual Research Review: Attention-deficit/hyperactivity disorder in girls and women: underrepresentation, longitudinal processes, and key directions

Attention-deficit/hyperactivity disorder (ADHD) - and its underlying behavioral dimensions of inattention and hyperactivity-impulsivity - have been understudied in females. We first cover the conceptual issues of prevalence, diagnostic practices, diversity, comorbidity, and causal factors, plus forces limiting awareness of ADHD in females. After a narrative review of cross-sectional and longitudinal findings, we conclude the following. (a) Girls meet diagnostic criteria for ADHD at just under half the rates of boys, a ratio that becomes much closer to equal by adulthood. (b) Girls and women with ADHD show a predominance of inattention and associated internalizing problems; boys and men display greater levels of hyperactive-impulsive symptoms and associated externalizing problems. (c) Sex differences in ADHD symptoms and related outcomes depend heavily on the clinical versus nonreferred nature of the samples under investigation. (d) Females with ADHD experience, on average, serious impairments, with a particularly heightened risk for problems in close relationships and engagement in self-harm. (e) Clinicians may overlook symptoms and impairments in females because of less overt (but still impairing) symptom manifestations in girls and women and their frequent adoption of compensatory strategies. Our review of predictors and mediators of adult outcomes highlights (a) the potential for heterotypically continuous pathways in females with childhood ADHD and (b) developmental progressions to self-harm, intimate partner violence, unplanned pregnancy, and comorbid psychopathology. Focusing on ADHD in females is necessary to characterize causal and maintaining mechanisms with accuracy and to foster responsive interventions, as highlighted in our closing list of clinical implications and research priorities.

Do we over-diagnose ADHD in North America? A critical review and clinical recommendations

There has been a marked increase in the prevalence of attention-deficit/hyperactivity disorder (ADHD) in the last 25 years in North America. Some see this trend as positive and believe that it reflects a better identification of ADHD and even think that the disorder is still under-diagnosed. Others, however, contend that ADHD is over-diagnosed. To help mental health clinicians to maintain an informed and nuanced perspective on this debate, this critical review aims to (1) summarize empirical results on factors that might contribute to increase the number of ADHD diagnoses and (2) propose clinical recommendations coherent with these findings to improve clinical practices for ADHD assessment and treatment. We conclude that artifactual factors such as current formulation of diagnostic criteria, clinical practices, and inordinate focus on performance, which is rampant in North America, likely contribute to inflated prevalence rates.

Clinical characteristics, neuroimaging findings, and neuropsychological functioning in attention-deficit hyperactivity disorder: Sex differences

Recent clinical studies, in both children/adolescents and adults, have shown the extreme neuropsychological heterogeneity of attention-deficit hyperactivity disorder (ADHD): specific neuropsychological deficits have been found only in a minority of individuals, with no direct correlation between discrete cognitive performances and the trajectory of clinical symptoms. Deficits in specific neuropsychological functions may be common in ADHD, but nevertheless no cognitive or neuropsychological profile may fully explain the disorder. Sex differences in the ADHD presentation, both at a neuropsychological and clinical level, also contribute to this clinical and neuropsychological heterogeneity. At a neuropsychological level, females with ADHD may show greater working memory problems, poorer vocabulary skills and worse visual spatial reasoning. Structural and functional imaging study also show discrete differences across sex; however, the great majority of clinical studies mainly or exclusively include male participants with insufficient data to draw firm conclusions on sex differences within the disorder. Here, we report the recent literature data, discussing still open research questions about the clinical presentation, neuroimaging findings, and neuropsychological functioning in ADHD with a focus on the impact of sex differences-a deeper insight in these unresolved issues may have relevant clinical and therapeutic implications for tailored, effective, and long-lasting interventions.

Relationship between sex hormones, reproductive stages and ADHD: a systematic review

OBJECTIVE

This systematic review aims to summarize current available evidence for the relationship between sex hormones or reproductive life stages (adrenarche in males and females, menarche, pregnancy, postpartum and menopause) and ADHD.

METHODS

We systematically reviewed studies investigating the relationship between sex hormones and symptoms of inattention and/or hyperactivity in individuals with an ADHD diagnosis or equivalent assessment of symptoms with validated scales. Articles were screened sequentially by two reviewers who were clinically and academically familiar with ADHD. Studies were rated according to Oxford Levels of Evidence (CEBM 2009).

RESULTS

Four studies matched inclusion criteria. One article was a case report of a female with ADHD and premenstrual syndrome experiencing worsening symptoms prior to each period (Quinn, J Clin Psychol 61:579-587, 2005). Another was a review article analysing literature relating to the effect of hormones on ADHD symptoms and supporting that a relationship exists between ADHD symptoms and sex hormone levels, without further characterization (Haimov-Kochman and Berger, Front Hum Neurosci 8, 2014). Giotakos and colleagues found no relationship between Wender Utah scores and sex hormone levels (Giotakos et al., J Forensic Psychiatry Psychol 16:423-433, 2005). An exploratory study by Ostojic and Miller found evidence for an association between early pubertal onset, inattention and risk-taking behaviour (Ostojic and Miller, J Atten Disord 20:782-791, 2016).

CONCLUSION

The literature on the relationship between sex hormones and ADHD is limited. Available studies present contradicting information. It is not known how this lack of evidence affects the treatment of ADHD during the lifespan. Further research is required to correctly characterize the mechanisms behind ADHD symptoms and its potential association with sex hormones.

The association between prenatal perfluoroalkyl substance exposure and symptoms of attention-deficit/hyperactivity disorder in 8-year-old children and the mediating role of thyroid hormones in the Hokkaido study

BACKGROUND

Disruption of thyroid hormone (TH) levels during pregnancy contributes to attention deficit hyperactivity disorder (ADHD). Exposure to perfluoroalkyl substances (PFAS) during gestation may affect levels of maternal and neonatal TH; however, little is known about the effect of PFAS on ADHD mediated by TH.

OBJECTIVES

We investigated the impact of maternal PFAS exposure on children's ADHD symptoms with the mediating effect of TH.

METHODS

In a prospective birth cohort (the Hokkaido study), we included 770 mother-child pairs recruited between 2002 and 2005 for whom both prenatal maternal and cord blood samples were available. Eleven PFAS were measured in maternal serum obtained at 28-32 weeks of gestation using ultra-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry. TH and thyroid antibody, including thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), free thyroxine (FT4), thyroid peroxidase antibody (TPOAb), and thyroglobulin antibody (TgAb) were measured in maternal blood during early pregnancy (median 11 gestational weeks) and in cord blood at birth. ADHD symptoms in the children at 8 years of age were rated by their parents using the ADHD-Rating Scale (ADHD-RS). The cut-off value was set at the 80th percentile for each sex.

RESULTS

Significant inverse associations were found between some PFAS in maternal serum and ADHD symptoms among first-born children. Assuming causality, we found only one significant association: maternal FT4 mediated 17.6% of the estimated effect of perfluoroundecanoic acid exposure on hyperactivity-impulsivity among first-born children.

DISCUSSION

Higher PFAS levels in maternal serum during pregnancy were associated with lower risks of ADHD symptoms at 8 years of age. The association was stronger among first-born children in relation to hyperactivity-impulsivity than with regard to inattention. There was little mediating role of TH during pregnancy in the association between maternal exposure to PFAS and reduced ADHD symptoms at 8 years of age.

Children and adolescents with ADHD followed up to adulthood: a systematic review of long-term outcomes

The objective is to highlight the clinical and social outcomes among adults who suffered from Attention-Deficit Hyperactivity Disorder (ADHD) in their childhood/adolescence. PubMed, PsycINFO, and Scopus databases were searched for prospective studies published during the last 5 years addressing patients with ADHD in childhood/adolescence followed-up to adulthood. We also included studies published before 2015 reported in other reviews with similar outcomes. Thousand four-hundred and eighty-five studies were identified, but only 39 were included for qualitative analysis and 27 for quantitative analysis. Overall, we found that ADHD persisted into adulthood with a mean rate of 43% and was mainly associated with both substance/alcohol use disorders and antisocial behavior and, less frequently, with anxiety and depressive disorders. The prevalence of persistent ADHD in adulthood reported by studies published after 2011 (55%) was higher than that reported by studies published previously from 1985 to 2011 (34%), suggesting a greater focus on ADHD in recent years. Our results highlight that ADHD can be considered not only a neurodevelopmental disorder, but also a persistent and complex condition, with detrimental consequences for quality of life in adulthood.

Understanding the complexity of neurodevelopmental profiles of females in prison

PURPOSE

This paper aims to examine the relationship between patterns of functioning in four domains (attention and concentration; social and communication; coordination and organisation; and literacy and numeracy) in women in prison. Also, to consider potential associations between functioning and previous Neurodevelopmental Disorder (NDD) diagnoses, previous mental health diagnoses and history of head injury, self-harm and attempted suicide.

DESIGN/METHODOLOGY/APPROACH

Women in one Scottish prison were invited to participate; 87 consented. Women were screened for functional difficulties and asked about their relevant educational and medical history.

FINDINGS

Half of participants reported difficulties in one or more domains. All possible combinations of functional difficulties were found. Only eight women reported previous NDD diagnoses. Functional difficulties were significantly associated with history of self-harm, history of attempted suicide and mental health diagnoses. In total, 32% of women reported at least one head injury, but this was not significantly associated with functional difficulties.

RESEARCH LIMITATIONS/IMPLICATIONS

The sample was comparatively small and questions were self-report. Analyses were based on within-cohort comparisons due to a lack of appropriate general population data.

PRACTICAL IMPLICATIONS

There is a clear need for timely, practical and comprehensive profiling of females in the Justice System. Current systems do not appear to adequately identify women with functional difficulties or other adversity. Greater use of interdisciplinary working and shared training is indicated, as is a move from categorical diagnostic systems towards dimensional approaches.

ORIGINALITY/VALUE

This study is the first to investigate associations between difficulties associated with NDDs, mental health difficulties and head injury in women in prison.

Prenatal exposure to per- and polyfluoroalkyl substances (PFAS) and associations with attention-deficit/hyperactivity disorder and autism spectrum disorder in children

BACKGROUND

Prenatal exposure to per- and polyfluoroalkyl substances (PFAS) may be a risk factor for neurodevelopmental deficits and disorders, but evidence is inconsistent.

OBJECTIVES

We investigated whether prenatal exposure to PFAS were associated with childhood diagnosis of attention-deficit/hyperactivity disorder (ADHD) or autism spectrum disorder (ASD).

METHODS

This study was based on the Norwegian Mother, Father and Child Cohort Study and included n = 821 ADHD cases, n = 400 ASD cases and n = 980 controls. Diagnostic cases were identified by linkage with the Norwegian Patient Registry. In addition, we used data from the Medical Birth Registry of Norway. The study included the following PFAS measured in maternal plasma sampled mid-pregnancy: Perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnDA), perfluorohexane sulfonate (PFHxS), perfluoroheptanesulfonic acid (PFHpS), and perfluorooctane sulfonate (PFOS). Relationships between individual PFAS and ADHD or ASD diagnoses were examined using multivariable adjusted logistic regression models. We also tested for possible non-linear exposure-outcome associations. Further, we investigated the PFAS mixture associations with ASD and ADHD diagnoses using a quantile-based g-computation approach.

RESULTS

Odds of ASD was significantly elevated in PFOA quartile 2 [OR = 1.71 (95% CI: 1.20, 2.45)] compared to quartile 1, and PFOA appeared to have a non-linear, inverted U-shaped dose-response relationship with ASD. PFOA was also associated with increased odds of ADHD, mainly in quartile 2 [OR = 1.54 (95% CI: 1.16, 2.04)] compared to quartile 1, and displayed a non-linear relationship in the restricted cubic spline model. Several PFAS (PFUnDA, PFDA, and PFOS) were inversely associated with odds of ADHD and/or ASD. Some of the associations were modified by child sex and maternal education. The overall PFAS mixture was inversely associated with ASD [OR = 0.76 (95% CI: 0.64, 0.90)] as well as the carboxylate mixture [OR = 0.79 (95% CI: 0.68, 0.93)] and the sulfonate mixture [OR = 0.84 (95% CI: 0.73, 0.96)].

CONCLUSION

Prenatal exposure to PFOA was associated with increased risk of ASD and ADHD in children. For some PFAS, as well as their mixtures, there were inverse associations with ASD and/or ADHD. However, the inverse associations reported herein should not be interpreted as protective effects, but rather that there could be some unresolved confounding for these relationships. The epidemiologic literature linking PFAS exposures with neurodevelopmental outcomes is still inconclusive, suggesting the need for more research to elucidate the neurotoxicological potential of PFAS during early development.

Sex-dependent complex association of TPH2 with multiple dimensions of ADHD

BACKGROUND

Tryptophan hydroxylase 2 (TPH2) is a key enzyme in the biosynthesis of serotonin in the brain. This study aims to investigate the role of a functional variant in TPH2 (rs17110747) in the pathophysiology of ADHD. This variant has been implicated in mood disorders in recent meta-analysis. This study uses a comprehensive approach that combines association testing and pharmaco-dynamic evaluation of behaviour, in a large sample of children with ADHD (n = 570).

METHODS

The association between various ADHD relevant traits and rs17110747 was analyzed using family-based association tests (FBAT). Children were assessed by parents, teachers and research staff under three experimental conditions (EC): baseline, placebo, and methylphenidate using a double-blind placebo-controlled crossover trial.

OUTCOMES

FBAT analysis conducted in a sample stratified based on sex of the proband, showed that there was a highly significant overtransmission of the G allele from parents to affected girls. In addition, significant association with several behavioral and cognitive dimensions of ADHD was observed only when the proband was female. Further, girls with the G/G genotype (rs17110747) had greater response to placebo when evaluated by parents.

INTERPRETATION

These results suggest that there may be a complex association of TPH2 in the etiology of ADHD, with a sex-specific effect.

Gender and age differences in the presentation of at-risk or probable Developmental Coordination Disorder in adults

BACKGROUND

Developmental Coordination Disorder (DCD), also called Dyspraxia, is a common Neurodevelopmental Disorder (NDD) that affects motor coordination with a marked impact on both academic and day-to-day living activities. It is increasingly clear that NDDs such as Attention-Deficit/Hyperactivity Disorder and Autism Spectrum Disorder may present differently in males and females, resulting in underdiagnoses of women and girls.

AIMS

To consider age and gender differences in the presentation of at-risk and probable DCD.

METHODS AND PROCEDURES

A sample of 1,476 adults aged 16-60 years were surveyed online using the Adult DCD Checklist.

OUTCOMES AND RESULTS

Women with at-risk (n = 1 8 6, 1 6. 6 %) or probable DCD (n = 6 4 3, 5 6. 6 %) reported significantly greater gross motor and non-motor difficulties and significantly greater impact on activities and participation, whereas men with at-risk (n = 58,16.3 %) or probable (n = 177,49.9 %), DCD reported significantly greater fine motor difficulties. Emerging adults (aged 16-25 years) with at-risk (n = 65,14.3 %) or probable (293,64.3 %) DCD reported significantly greater non-motor difficulty than adults (aged 26-60+ years) with at-risk (n = 179,17.5 %) or probable (n = 518, 50.8 %) DCD.

CONCLUSIONS AND IMPLICATIONS

Both age and gender differences were found in the presentation of at-risk and probable DCD in adults. This may have implications for the development of future DCD assessment tools and for the training of front-line staff who may encounter individuals with DCD throughout their lives, including teachers, doctors and employers' Human Resources and Occupational Health staff.

The subject matters: relations among types of anxiety, ADHD symptoms, math performance, and literacy performance

In this study, we extended a model of the relations among ADHD symptoms, anxiety, and academic performance. Undergraduates (N = 515) completed self-report measures of anxiety (i.e. trait, test, math, and literacy) and ADHD symptoms. During the study, they completed math and literacy measures and reported their current (i.e. state) anxiety three times. There were significant correlations among ADHD symptoms and all measures of anxiety. However, neither ADHD symptoms nor trait anxiety were correlated with math or literacy performance. Test-anxious students reported increasing state anxiety as the study progressed. In contrast, math-anxious students reported increased state anxiety following the math tasks but not the literacy tasks and literacy-anxious students reported increased state anxiety following the literacy tasks but not the math tasks. With respect to performance, math-anxious students had worse math performance and literacy-anxious students had worse literacy performance whereas test anxiety was not directly related to performance on either math or literacy tasks. Patterns of relations did not differ for men and women, but, except for literacy anxiety, women reported higher levels of all types of anxiety. These results could help educators understand how affective responses are related to university students' academic performance.

Metal and essential element concentrations during pregnancy and associations with autism spectrum disorder and attention-deficit/hyperactivity disorder in children

BACKGROUND

Prenatal exposure to toxic metals or variations in maternal levels of essential elements during pregnancy may be a risk factor for neurodevelopmental disorders such as attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) in offspring.

OBJECTIVES

We investigated whether maternal levels of toxic metals and essential elements measured in mid-pregnancy, individually and as mixtures, were associated with childhood diagnosis of ADHD or ASD.

METHODS

This study is based on the Norwegian Mother, Father and Child Cohort Study and included 705 ADHD cases, 397 ASD cases and 1034 controls. Cases were identified through linkage with the Norwegian Patient Registry. Maternal concentrations of 11 metals/elements were measured in blood at week 17 of gestation; cadmium; cesium; cobalt; copper; lead; magnesium; manganese; selenium; zinc; total arsenic; and total mercury. Multivariable adjusted logistic regression models were used to examine associations between quartile levels of individual metals/elements and outcomes. We also investigated non-linear associations using restricted cubic spline models. The joint effects of the metal/element mixture on ASD and ADHD diagnoses were estimated using a quantile-based g-computation approach.

RESULTS

For ASD, we identified positive associations (increased risks) in the second quartile of arsenic [OR = 1.77 (CI: 1.26, 2.49)] and the fourth quartiles of cadmium and manganese [OR = 1.57 (CI: 1.07 2.31); OR = 1.84 (CI: 1.30, 2.59)], respectively. In addition, there were negative associations between cesium, copper, mercury, and zinc and ASD. For ADHD, we found increased risk in the fourth quartiles of cadmium and magnesium [OR = 1.59 (CI: 1.15, 2.18); [OR = 1.42 (CI: 1.06, 1.91)]. There were also some negative associations, among others with mercury. In addition, we identified non-linear associations between ASD and arsenic, mercury, magnesium, and lead, and between ADHD and arsenic, copper, manganese, and mercury. There were no significant findings in the mixture approach analyses.

CONCLUSION

Results from the present study show several associations between levels of metals and elements during gestation and ASD and ADHD in children. The most notable ones involved arsenic, cadmium, copper, mercury, manganese, magnesium, and lead. Our results suggest that even population levels of these compounds may have negative impacts on neurodevelopment. As we observed mainly similarities among the metals' and elements' impact on ASD and ADHD, it could be that the two disorders share some neurochemical and neurodevelopmental pathways. The results warrant further investigation and replication, as well as studies of combined effects of metals/elements and mechanistic underpinnings.

Gender differences in externalizing and internalizing problems in Singaporean children and adolescents with attention-deficit/hyperactivity disorder

BACKGROUND

Studies on gender differences in attention-deficit/hyperactivity disorder (ADHD) comorbidities in the Asian populations have been limited and previous studies have shown inconclusive findings. Singapore is a city-state country in Southeast Asia with a population of 5.7 million. This study examined gender differences in internalizing and externalizing problems in Singaporean children and adolescents with ADHD. The plausible social factors underlying the gender differences were discussed.

METHODS

A total of 773 participants (aged 6 to 18, 88% males) newly diagnosed with ADHD were recruited from the largest public child and adolescent psychiatric center in Singapore. Their internalizing and externalizing problems were assessed using the Child Behavioral Checklist and Teacher's Report Form by parents and teachers respectively. Demographics and relevant social factors were collected using parent questionnaires.

RESULTS

Females with ADHD were reported to have less delinquent and aggressive behavior but more depressive symptoms than their male counterparts, similar to findings in the Western literature. Gender remained a significant predictor of externalizing problem after controlling for other factors. Lower socioeconomic status and parental use of physical punishment were significant predictors of both internalizing and externalizing problems.

CONCLUSIONS

Gender differences in ADHD comorbidities do exist in the Asian clinical population. The lack of externalizing symptoms in females with ADHD has made timely referral and diagnosis challenging. More research is needed in understanding the gender differences in ADHD and the biopsychosocial mechanism underlying the differences in order to improve the detection of ADHD in females.

Maternal Sociodemographic Factors Are Associated with Methylphenidate Initiation in Children in the Netherlands: A Population-Based Study

Multiple factors may contribute to the decision to initiate methylphenidate treatment in children such as maternal sociodemographic factors of which relatively little is known. The objective was to investigate the association between these factors and methylphenidate initiation. The study population included 4243 children from the Generation R Study in the Netherlands. Maternal sociodemographic characteristics were tested as determinants of methylphenidate initiation through a time-dependent Cox regression analysis. Subsequently, we stratified by mother-reported ADHD symptoms (present in 4.2% of the study population). When ADHD symptoms were absent, we found that girls (adjusted HR 0.25, 95%CI 0.16-0.39) and children born to a mother with a non-western ethnicity (compared to Dutch-Caucasian) (adjusted HR 0.42, 95%CI 015-0.68) were less likely to receive methylphenidate. They were more likely to receive methylphenidate when their mother completed a low (adjusted HR 2.29, 95%CI 1.10-4.77) or secondary (adjusted HR 1.71, 95%CI 1.16-2.54) education. In conclusion, boys and children born to a mother of Dutch-Caucasian ethnicity were more likely to receive methylphenidate, irrespective of the presence of ADHD symptoms.

Sex Differences in the Meaning of Parent and Teacher Ratings of ADHD Behaviors: An Observational Study

Objective: To test explanations for the underrecognition of female ADHD by examining differences in adult ratings of boys and girls matched for levels of directly observed ADHD behaviors. Method: In a secondary analysis of a population-based sample, 3- to 4-year-olds (n = 153, 79 male) and 8- to 9-year-olds (n = 144, 75 male) were grouped according to levels of directly observed ADHD behaviors (low/moderate/high). Groups were then compared with parent/teacher ADHD ratings. Results: There were no sex differences in levels of directly observed ADHD behaviors within groups. For preschoolers, parents' ratings of males, but not females, significantly increased across groups-mirroring levels of observed behaviors. For older children, both parent and teacher mean ratings were significantly higher for males than females across groups. Conclusion: Identified differences in adult ratings of males and females matched for directly observed behaviors may contribute to understanding the substantial ADHD underrecognition in females.

Gender differences in adult ADHD: Cognitive function assessed by the test of attentional performance

Introduction

The aim of this study was to assess cognitive differences between male and female adults with Attention Deficit Hyperactivity Disorder (ADHD).

Methods

Patients with an ADHD diagnosis according to the DSM-IV guidelines were included in a cross-sectional study evaluating cognitive measures. 28 women and 41 men from ages 19 to 56 completed self-report questionnaires and performed a computer-based test of attentional performance (TAP). The TAP assesses cognitive functions highly affected in ADHD patients, including working memory, alertness and attention as well as behavioral control and response inhibition.

Results

There were no measurable differences in self-report scales assessing current symptomology between the sexes, however men scored higher on the scale for childhood symptoms. Performance measures for general wakefulness were comparable between men and women, while working memory and behavioral control test results differed. Females reacted significantly slower and more unstable for both the TAP Go/NoGo paradigm and working memory subtest, while also making more errors in the latter.

Conclusions

We found gender-specific effects regarding working memory and behavioral control in this sample of adult patients with ADHD. Further studies are warranted, examining whether these differences relate to differences in clinical presentation and comorbidity patterns between men and women.

The effects of sex on prevalence and mechanisms underlying neurodevelopmental disorders

Neurodevelopmental disorders occur more frequently in boys than in girls and often differ in presentation between the sexes. The sex differences in prevalence and presentation of autism spectrum disorder, intellectual disability, communication disorders, specific learning disabilities, attention deficit/hyperactivity disorder, Tourette's syndrome, and epilepsy are discussed, as well as sex differences in the patterns of comorbidities between these disorders. Prominent theories have been proposed to explain sex biases. These include genetic factors, sex hormones, sociological factors, cognitive differences between the sexes, and environmental insult. Despite the large body of research reviewed in this chapter, many aspects of sex-related effects in neurodevelopmental disorders remain poorly understood.

The female side of pharmacotherapy for ADHD-A systematic literature review

OBJECTIVE

This comprehensive review examined sex differences in prescription rates and efficacy or effectiveness of pharmacotherapy treatment in girls and women with attention deficit hyperactivity disorder (ADHD), while identifying gaps in the scientific knowledge on this topic.

METHOD

A rigorous electronic database search was carried out in order to identify all published studies on female-specific effects of stimulants and non-stimulants in the treatment of ADHD. In total, 2672 studies were screened of which 21 studies (seven on prescription rates, 14 on effects of pharmacotherapy) met the inclusion criteria and were included for analysis.

RESULTS

In all seven studies on ADHD prescription rates, girls received significantly less prescriptions than boys, a difference however no longer seen in adults with the exception of one study. Each of the 14 studies on effectiveness / efficacy found at least one sex-difference in the effects of ADHD pharmacotherapy.

CONCLUSION

Several sex-differences are demonstrated in the prescription, usage and efficacy /effectiveness of both stimulant and non-stimulant ADHD pharmacotherapy. A single daily use of MPH may possibly not be optimal for girls with ADHD and ATX may be a promising medication for girls and women with ADHD. The robustness of this result requires further investigation.

Unseen and Stressed? Gender Differences in Parent and Teacher Ratings of ADHD Symptoms and Associations With Perceived Stress in Children With ADHD

Objective: In this study, we investigate the differences between parent and teacher ADHD ratings, and how these ratings relate to perceived stress in children with ADHD. Method: Ratings by parents and teachers with the Swanson, Nolan and Pelham ADHD symptom rating scale (SNAP-IV) were collected from children with a clinical diagnosis of ADHD (n = 137). Also, information on medication was collected. Children (≥11 years of age; n = 64) were invited to complete the Pressure-Activation-Stress scale. Results: Among girls, but not boys, teacher ratings were significantly lower than parental ratings on all symptom scales. Lower teacher ratings on hyperactivity symptoms were associated with higher levels of perceived stress. Conclusion: The findings suggest a potential gender bias in ratings among teachers. Underrated, and hence underidentified, ADHD problems in the school setting seem to increase the perception of stress in the sense of pressure for both girls and boys.

A multicenter effectiveness trial of QEEG-informed neurofeedback in ADHD: Replication and treatment prediction

•

QEEG-informed neurofeedback resulted in remission rates of 55%.

•

In the total sample, non-remitters had higher hyperactivity scores at baseline.

•

In women, non-remitters had longer P300 latencies.

•

In boys, a low individual alpha peak frequency (iAPF) was associated with remission.

Introduction

Quantitative Electroencephalogram-(QEEG-)informed neurofeedback is a method in which standard neurofeedback protocols are assigned, based on individual EEG characteristics in order to enhance effectiveness. Thus far clinical effectiveness data have only been published in a small sample of 21 ADHD patients. Therefore, this manuscript aims to replicate this effectiveness in a new sample of 114 patients treated with QEEG-informed neurofeedback, from a large multicentric dataset and to investigate potential predictors of neurofeedback response.

Methods

A sample of 114 patients were included as a replication sample. Patients were treated with standard neurofeedback protocols (Sensori-Motor-Rhythm (SMR), Theta-Beta (TBR), or Slow Cortical Potential (SCP) neurofeedback), in combination with coaching and sleep hygiene advice. The ADHD Rating Scale (ADHD-RS) and Pittsburgh Sleep Quality Index (PSQI) were assessed at baseline, every 10th session, and at outtake. Holland Sleep Disorder Questionnaire (HSDQ) was assessed at baseline and outtake. Response was defined as ≥25% reduction (R25), ≥50% reduction (R50), and remission. Predictive analyses were focused on predicting remission status.

Results

In the current sample, response rates were 85% (R25), 70% (R50), and remission was 55% and clinical effectiveness was not significantly different from the original 2012 sample. Non-remitters exhibited significantly higher baseline hyperactivity ratings. Women who remitted had significantly shorter P300 latencies and boys who remitted had significantly lower iAPF’s.

Discussion

In the current sample, clinical effectiveness was replicated, suggesting it is possible to assign patients to a protocol based on their individual baseline QEEG to enhance signal-to-noise ratio. Furthermore, remitters had lower baseline hyperactivity scores. Likewise, female remitters had shorter P300 latencies, whereas boys who remitted have a lower iAPF. Our data suggests initial specificity in treatment allocation, yet further studies are needed to replicate the predictors of neurofeedback remission.

ICP-MS Assessment of Hair Essential Trace Elements and Minerals in Russian Preschool and Primary School Children with Attention-Deficit/Hyperactivity Disorder (ADHD)

The objective of the present study was to investigate the relationship between hair essential trace element and mineral content and ADHD in preschool (4-6 years old) and primary school children (6-10 years old) in relation to age and gender. Hair essential trace element and mineral content in 90 Russian children with ADHD and 90 age- and gender-matched neurotypical controls were assessed using inductively coupled plasma mass-spectrometry after microwave digestion. The obtained data demonstrate that hair Co, Cu, Mn, Si, and Zn contents in ADHD children was significantly reduced by 18%, 10%, 27%, 16%, and 19% as compared to the control values, respectively. The most significant decrease in children with ADHD was observed for hair Mg levels, being 29% lower than those in neurotypical children. After adjustment for age and gender, the observed difference in hair element content was more characteristic for preschool children and girls, respectively. Multiple linear regression analysis demonstrated that in a crude model (hair element levels as predictors), only hair Zn content was significantly inversely associated with ADHD (β = - 0.169; p = 0.025). Adjustment for anthropometric parameters (model 2) did not increase the predictive ability of the model, although it improved the association between hair Zn and ADHD in children (β = - 0.194; p = 0.014). Hypothetically, the observed alterations may at least partially contribute to neurobehavioral disturbances in children with ADHD. Moreover, the results of the present study raise the question about the potential benefits of Zn and Mg supplementation in children with ADHD. However, further detailed studies are required to investigate micronutrient deficiencies in ADHD.

Toxoplasma gondii infection and risk of attention-deficit hyperactivity disorder: a systematic review and meta-analysis

Toxoplasma gondii (T. gondii), as an opportunistic neurotropic parasite of the Apicomplexa family, was firstly described in 1908. As attention-deficit hyperactivity disorder (ADHD) is one of the most common neuropsychiatric disorders in children and adolescents and often persists into adulthood, the purpose of this systematic review and meta-analysis was to investigate the relationship between T. gondii infection and ADHD.The data were systematically collected from seven electronic databases up to May 1^st 2019 with no language restriction. This study was registered at the International Prospective Register of Systematic Reviews (PROSPERO; code: CRD42020149353). Odds ratios (ORs) and 95% confidence intervals (CI) were estimated using a random effects model. Seven studies involving five cross-sectional and two case-control studies were included in this meta-analysis.Results indicated that there was a statistically non-significant association between exposure to T. gondii infection and increased risk of ADHD based on the detection of immunoglobulin G (IgG) antibody (2.02 [95% CI: 0.97-4.20]; I²=58.7%). However, obtained results of Egger's tests for anti-T. gondii IgG antibody showed publication bias (P=0.014).Sensitivity analysis revealed stable results for the association between anti-T. gondii IgG antibody with ADHD.Given the small number of studies in this field and the obtained results, it cannot be conclusively stated that T. gondii is a risk factor for ADHD.It is important to have reliable information about the relationship between T. gondii and ADHD around the world; as it may lead to better insight to elucidate the possible association of toxoplasmosis and the pathogenesis of ADHD.

The Functional Impact of Sleep Disorders in Children With ADHD

Objective: Children with ADHD display higher rates of sleep problems, and both sleep disorders and ADHD have been shown to affect functioning in childhood. The current study examines the frequency and relationship between sleep problems and ADHD, and their impact on quality of life (QoL) and functional impairment. Method: Parents of 192 children with ADHD (M = 10.23 years) completed measures regarding their child's ADHD symptoms (Swanson, Nolan and Pelham [SNAP]), sleep disorders (Pediatric Sleep Questionnaire [PSQ]), QoL (Child Health Illness Profile [CHIP-PE]), and functioning (Weiss Functional Impairment Rating Scale-Parent Report [WFIRS-P]). Results: Common sleep complaints in participants were insomnia, excessive daytime sleepiness (EDS), and variability in sleep schedule. Regression analysis indicated that sleep problems and ADHD symptoms independently predicted lower levels of QoL (ΔR² = .12, p < .001) and social functioning (ΔR² = .12, p < .001). Conclusion: The results suggest that ADHD may coexist with somnolence and that both conditions have a significant impact on a child's functioning and QoL.