Comorbidity of Attention Deficit Hyperactivity Disorder and Generalized Anxiety Disorder in children and adolescents

Optimal interval and feature selection in activity data for detecting attention deficit hyperactivity disorder

Attention deficit hyperactivity disorder (ADHD) is a heterogeneous neurobehavioral disorder that is common in children and adolescents. Inattention, impulsivity, and hyperactivity are the key symptoms of ADHD patients. Traditional clinical assessments delay ADHD diagnosis and increase undiagnosed cases and costs, as well. The use of deep learning (DL) and machine learning (ML)-based objective techniques for diagnosing ADHD has grown exponentially in recent years as the efficiency of early diagnosis has improved. This research highlights the significance of utilizing feature selection techniques before constructing machine learning models on activity datasets. It also explores the distinctions between specific time-interval activity data and broader interval activity data in identifying ADHD patients from the clinical control group. Five ML models were developed and tested to assess the performance of two sets of features and different categories of activity data in predicting ADHD. The study concludes with the following findings: (i) the model's performance showed a notable improvement of 0.11 in accuracy with the adoption of a precise feature selection process; (ii) activity data recorded in the morning and at night are more significant predictors of ADHD compared to other times; (iii) the utilization of specific time interval data is crucial for ADHD prediction; (iv) the random forest performs better than the other machine learning models used in the study, with 84% accuracy, 79% precision, 85% F1-score, and 92% recall. As we move into an era where early disease prediction is possible, combining artificial intelligence methods with activity data could create a strong framework for helping doctors make decisions that can be used far beyond hospitals.

Longitudinal associations between family functioning and generalized anxiety among adolescents: the mediating role of self-identity and cognitive flexibility

BACKGROUND

Generalized anxiety (GA) is showing a high prevalence among adolescents nowadays; investigations on influencing factors and potential mechanisms are important to inform intervention development. The present two-wave study investigated the ways in which family functioning predicted GA six months later among adolescents, by considering the mediating role of self-identity and cognitive flexibility.

METHODS

Adolescents were recruited from 27 randomly selected classes in two secondary schools in Chongqing and Fujian Province, China. Survey questionnaires assessing family functioning, self-identity, cognitive flexibility and GA were obtained from 1223 adolescents (Mage = 13.14, SD = 1.35) at two time points of the 6-month interval.

RESULTS

The association between family functioning (T1) and GA (T2) was significant (r= -0.152, p < 0.01). Self-identity and cognitive flexibility sequentially mediated the relationship between family functioning (T1) and GA (T2) (with the indirect effect = -0.005, 95% CI = -0.007~ -0.002) after controlling for age, gender, and GA at baseline. Cognitive flexibility also showed a significant and direct mediating effect (with the indirect effect = -0.008, 95% CI = -0.012 ~ -0.005).

CONCLUSION

Findings indicated that family functioning can be a protective factor of GA, and self-identity and cognitive flexibility act as a crucial role in the association between family functioning and GA. Future studies should adopt more time points and long-term follow-up assessments using more robust approaches to improve the reliability of the study findings. Findings may offer some implications that building a harmonious, open and warm family and guiding adolescents to develop self-identity as well as more flexible cognitive style could be helpful to prevent and cope with anxious emotion.

Identification of Novel Genomic Loci for Anxiety and Extensive Genetic Overlap with Psychiatric Disorders

Background

Anxiety disorders are prevalent and anxiety symptoms co-occur with many psychiatric disorders. We aimed to identify genomic risk loci associated with anxiety, characterize its genetic architecture, and genetic overlap with psychiatric disorders.

Methods

We used the GWAS of anxiety symptoms, schizophrenia, bipolar disorder, major depression, and attention deficit hyperactivity disorder (ADHD). We employed MiXeR and LAVA to characterize the genetic architecture and genetic overlap between the phenotypes. Conditional and conjunctional false discovery rate analyses were performed to boost the identification of genomic loci associated with anxiety and those shared with psychiatric disorders. Gene annotation and gene set analyses were conducted using OpenTargets and FUMA, respectively.

Results

Anxiety was polygenic with 12.9k estimated genetic risk variants and overlapped extensively with psychiatric disorders (4.1-11.4k variants). MiXeR and LAVA revealed predominantly positive genetic correlations between anxiety and psychiatric disorders. We identified 114 novel loci for anxiety by conditioning on the psychiatric disorders. We also identified loci shared between anxiety and major depression (n = 47), bipolar disorder (n = 33), schizophrenia (n = 71), and ADHD (n = 20). Genes annotated to anxiety loci exhibit enrichment for a broader range of biological pathways and differential tissue expression in more diverse tissues than those annotated to the shared loci.

Conclusions

Anxiety is a highly polygenic phenotype with extensive genetic overlap with psychiatric disorders. These genetic overlaps enabled the identification of novel loci for anxiety. The shared genetic architecture may underlie the extensive cross-disorder comorbidity of anxiety, and the identified genetic loci implicate molecular pathways that may lead to potential drug targets.

Neurodevelopmental risk and adaptation as a model for comorbidity among internalizing and externalizing disorders: genomics and cell-specific expression enriched morphometric study

BACKGROUND

Comorbidity is the rule rather than the exception for childhood and adolescent onset mental disorders, but we cannot predict its occurrence and do not know the neural mechanisms underlying comorbidity. We investigate if the effects of comorbid internalizing and externalizing disorders on anatomical differences represent a simple aggregate of the effects on each disorder and if these comorbidity-associated cortical surface differences relate to a distinct genetic underpinning.

METHODS

We studied the cortical surface area (SA) and thickness (CT) of 11,878 preadolescents (9-10 years) from the Adolescent Brain and Cognitive Development Study. Linear mixed models were implemented in comparative and association analyses among internalizing (dysthymia, major depressive disorder, disruptive mood dysregulation disorder, agoraphobia, panic disorder, specific phobia, separation anxiety disorder, social anxiety disorder, generalized anxiety disorder, post-traumatic stress disorder), externalizing (attention-deficit/hyperactivity disorder, oppositional defiant disorder, conduct disorder) diagnostic groups, a group with comorbidity of the two and a healthy control group. Genome-wide association analysis (GWAS) and cell type specificity analysis were performed on 4468 unrelated European participants from this cohort.

RESULTS

Smaller cortical surface area but higher thickness was noted across patient groups when compared to controls. Children with comorbid internalizing and externalizing disorders had more pronounced areal reduction than those without comorbidity, indicating an additive burden. In contrast, cortical thickness had a non-linear effect with comorbidity: the comorbid group had no significant CT differences, while those patient groups without comorbidity had significantly higher thickness compare to healthy controls. Distinct biological pathways were implicated in regional SA and CT differences. Specifically, CT differences were associated with immune-related processes implicating astrocytes and oligodendrocytes, while SA-related differences related mainly to inhibitory neurons.

CONCLUSION

The emergence of comorbidity across distinct clusters of psychopathology is unlikely to be due to a simple additive neurobiological effect alone. Distinct developmental risk moderated by immune-related adaptation processes, with unique genetic and cell-specific factors, may contribute to underlying SA and CT differences. Children with the highest risk but lowest resilience, both captured in their developmental morphometry, may develop a comorbid illness pattern.

Combined methylphenidate and fluoxetine treatment in adolescent rats significantly impairs weight gain with minimal effects on skeletal development

Methylphenidate (MP) is frequently prescribed to treat Attention-Deficit/Hyperactivity Disorder (ADHD); however, many patients with ADHD experience depression and anxiety. As such, concomitant administration of selective serotonin reuptake inhibitors such as fluoxetine (FLX) is common. Our laboratory and others have shown that MP impairs skeletal development in preclinical and clinical settings, and FLX has also been linked to skeletal deficits. Unfortunately, little is known about the effects of combined MP and FLX treatment on skeletal development. The objective of this study was to investigate the effects of MP and FLX on bone morphology and biomechanical properties in adolescent rats. Four-week-old male Sprague-Dawley rats were randomly divided into the following 4 groups: Water, MP, FLX, and MP + FLX. As body weights in the MP, FLX, and MP + FLX groups were all lower than Water, the data were compared directly and after adjusting to body weight via linear regression. The direct comparison revealed that MP + FLX rats had significantly shorter (~12 %) and narrower femora and tibiae (~10 %) compared to most other groups, along with shorter (26-35 %), disorganized tibial growth plates. MicroCT analyses of the trabecular compartment of the proximal tibia identified reductions of 47 % for TV, 86 % for BV, 74 % for BV/TV, 68 % for Tb.N, 25 % in Tb.Th, and 74 % in vBMD concomitant with increases of 44 % for Tb.Sp for MP + FLX compared to Water. Similar analyses of femoral midshaft cortical bone identified reductions of 29 % for Ct.V, 30 % for Ps.V, 30 % for Ec. V, and 51 % for pMOI, as well as increases of 17 % for Ct.Th and 2 % for TMD for MP + FLX compared to Water. Biomechanically, MP + FLX femora were weaker, as indicated by a reduction in ultimate force (14 %) in MP + FLX compared to Water. The microstructural and biomechanical effects of MP + FLX were eliminated after adjustment for body weight, though the detrimental effects on growth plate morphology remained. We conclude that while the adverse microstructural and biomechanical effects of MP + FLX seen via direct comparison are predominantly attributable to reductions in body weight rather than direct effects on bone, MP and FLX, particularly in combination show detrimental effects on growth plate structure and chondrocyte morphology. These findings warrant further research into the effect of these drugs on weight gain, skeletal development and growth plate morphology, as well as consideration by physicians treating children and adolescents with ADHD.

Treating ADHD and Comorbid Anxiety in Children: A Guide for Clinical Practice

Attention-deficit hyperactivity disorder (ADHD) is frequently comorbid with anxiety disorders with rates as high as 25% to 50% in children and adolescents. Despite various treatment options for ADHD symptoms, limited research addresses treatment in the context of comorbidity. This article seeks to provide a review of the evidence regarding treatment of this comorbid population. Distinct emotional, cognitive, and behavioral symptoms have been observed in this population, suggesting a need for tailored treatment. Despite common concerns about anxiety exacerbation, stimulant medications demonstrate good tolerability and good response in addressing symptoms. Atomoxetine has also demonstrated some benefit and good tolerability for treating this comorbid population. Selective serotonin reuptake inhibitors can be used as adjunctive treatment for anxiety but require careful monitoring of side effects. Cognitive behavioral therapy (CBT) is an important treatment to improve anxiety symptoms in the absence of significant ADHD symptoms. Psychosocial interventions are also essential to improve outcomes.

The Impact of Internalizing Symptoms on Impairment for Children With ADHD: A Strength-Based Perspective

BACKGROUND/PURPOSE

This study aims to investigate the influence of internalizing symptoms on functional impairment for children with ADHD, and whether child strengths and parenting strengths have moderating effects on this relationship.

METHODS

Participants included 209 children with ADHD and their caregivers seeking mental health services between the ages of 5 and 11 years. To examine the moderating effects of parenting and child strengths, ordinary least squares regression models were tested using the PROCESS macro for SPSS (v3.5).

RESULTS

Results suggest that levels of internalizing symptoms influence functional impairment in children with ADHD. Child strengths moderate the relationship between internalizing symptoms and functional impairment when internalizing symptoms are medium to high.

CONCLUSION

Findings from this study demonstrate that facilitating child strengths can help moderate functional impairment for children who experience ADHD and internalizing symptoms.

Assessing anxiety among adolescents in Hong Kong: psychometric properties and validity of the Generalised Anxiety Disorder-7 (GAD-7) in an epidemiological community sample

BACKGROUND

The development of a valid and simple-to-use self-administered tool in Asian adolescents for clinical screening and intervention remains limited. The present study assessed the psychometric characteristics and validity of the Generalised Anxiety Disorder Scale-7 (GAD-7) among adolescents in Hong Kong.

METHODS

Epidemiological data from 3,261 Hong Kong adolescents aged 15 - 24 years were analysed for the construct validity, criterion validity, concurrent validity, and Rasch Model. All analyses were age- and gender-weighted according to the distributions of Hong Kong's general population.

RESULTS

The GAD-7 showed high internal consistency and strong fit to the one-factor structure. The best cut-off value was set at 7 or more. Regression models found that the total scores of the scale were positively associated with symptoms of depression and hypomania, schizotypal personality and alcohol dependence. Rasch model analysis found that the separation index was 2.18 and 16.51 for the respondents and items, respectively and all residual pairs had small correlation coefficients (i.e., &lt; 0.3).

CONCLUSIONS

All psychometric findings presented in this study support the use of the GAD-7 as a legitimate measure of anxiety severity. A cut-off score of 7 should indicate a potential diagnosable condition in Asian adolescents, which requires our attention but should not be used as a formal diagnostic screening tool. The findings revealed the local dependence of the items of the GAD-7 and that the scale can separate respondents into at least two groups and items into numerous groups according to the separation index.

ADHD-inattentive versus ADHD-Combined subtypes: A severity continuum or two distinct entities? A comprehensive analysis of clinical, cognitive and neuroimaging data

The current study aimed to explore the multimodal differences between the inattentive ADHD (ADHD-I) subtype and the combined ADHD (ADHD-C) subtype. A large sample of medication-naïve children with pure ADHD (i.e., without any comorbidity) (145 with ADHD-I, 132 with ADHD-C) and healthy controls (n = 98) were recruited. A battery of multiple scales and cognitive tests were utilized to assess the clinical and cognitive profiles of each individual. In addition, structural and diffusion magnetic resonance imaging (MRI) were acquired for 120 subjects with ADHD and 85 controls. Regional gray matter volume, white matter volume, and diffusion tensors, e.g., axial diffusivity (AD), were compared among the three groups in a whole-brain voxel-wise manner. Compared with healthy controls, both ADHD groups exhibited elevated levels of behavioral and emotional problems. The ADHD-C group had more behavioral problems and emotional liability, as well as less anxiety, than the ADHD-I group. The two ADHD groups were equally impaired in most cognitive domains, with the exception of sustained attention. Compared with healthy controls, the ADHD-C group showed a high gray matter volume (GMV) in the bilateral thalamus and a high white matter volume in the body of the corpus callosum, while the ADHD-I group presented an elevated GMV mainly in the left precentral gyrus and posterior cingulate cortex. Compared with participants with ADHD-C and healthy controls, subjects with ADHD-I showed increased AD in widespread brain regions. Our study has revealed a distinct, interconnected pattern of behavioral, cognitive, and brain structural characteristics in children with different ADHD subtypes.

Understanding the Diversity of Pharmacotherapeutic Management of ADHD With Co-occurring Autism: An Australian Cross-Sectional Survey

OBJECTIVES

Attention deficit hyperactivity disorder (ADHD) frequently co-occurs with other neurodevelopmental diagnoses, such as autism spectrum disorder (autism), which can make clinical decision making around symptom management challenging for clinicians. There is a paucity of research examining pharmacotherapeutic management of children who have ADHD with co-occurring diagnoses. We aimed to report on the co-occurring diagnoses and symptom profile of children, and report on medication use, stratified by ADHD, autism and ADHD + autism diagnoses.

METHODS AND MATERIALS

Caregivers of 505 children (2-18 years) with ADHD (n = 239), autism (n = 117), and co-occurring ADHD + autism (n = 149) completed a questionnaire on current medication use and clinical rating scales about their child's symptoms, as part of a broader project investigating diagnosis and management of symptoms in children with ADHD or autism.

RESULTS

The parents of the ADHD group reported a higher proportion of their children had learning disorders (17.15%) and speech and language disorders (4.60%) compared to the parents of the autism and ADHD + autism groups. Parents of the ADHD + autism group reported higher proportions of intellectual disability (5.37%), oppositional defiant disorder (20.13%), anxiety (38.93%), depression (6.71%) and genetic conditions (3.36%) in their children, in comparison to the parents of the ADHD and autism groups. Children with ADHD were reported to be taking a higher proportion of psychotropic medication (90%), followed by ADHD + autism (86%) and autism (39%). The parents of children with ADHD + autism reported a higher proportion of non-stimulant ADHD medication (25.5%), antipsychotic (18.79%), antidepressant (22.15%) and melatonin (31.54%) use by their children, compared to the parents of the ADHD and autism groups.

CONCLUSIONS

A similar proportion of children with ADHD + autism and ADHD were reported to be taking medication. However, the types of medication taken were different, as expected with reported co-occurring diagnoses. The complexity of symptoms and diagnoses in ADHD + autism warrants targeted research to optimize management and therapeutic outcomes.

Attention Deficit Hyperactivity Disorder (ADHD) among elementary students in rural China: Prevalence, correlates, and consequences

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) is a widely recognized mental health problem in developed countries but remains under-investigated in developing settings. This study examines the prevalence, correlates, and consequences of ADHD symptoms among elementary school students in rural China.

METHODS

Cross-sectional data were collected from 6,719 students across 120 rural primary schools in China on ADHD symptoms, demographic characteristics, and academic performance in reading and math. ADHD symptoms were evaluated using the caregiver-reported ADHD Rating Scale-IV.

RESULTS

The prevalence of ADHD symptoms was 7.5% in our sample. Male students, students in lower grade levels, and students with lower cognitive ability showed a significantly higher prevalence of ADHD symptoms (ORs = 2.56, 2.06, and 1.84, respectively; p<0.05). Left-behind children showed a significantly lower prevalence of ADHD symptoms than did children who were living with their parents (OR = 0.74, p < 0.05). Adjusted regressions show that students with ADHD symptoms scored 0.12 standardized deviations lower in reading (p < 0.05) and 0.19 standardized deviations lower in math (p < 0.01).

LIMITATIONS

The ADHD Rating Scale-IV is a screening scale rather than a diagnostic test. Caregiver self-report measures also may underestimate ADHD symptoms for our sample.

CONCLUSIONS

ADHD is a common disorder among rural students in China and appears to be contributing to poor academic outcomes. The higher prevalence of ADHD among students with low cognitive ability also suggests that many rural children in China face multifactorial learning challenges. Taken together, the findings indicate a need for educators and policymakers in rural China to develop programs to reduce risk and support students with ADHD symptoms.

Depression and anxiety in cardiac rehabilitation: differential associations with changes in exercise capacity and quality of life

BACKGROUND

Cardiac rehabilitation (CR) has been successful in improving exercise capacity (EC) and quality of life (QoL). However, depression and anxiety are highly prevalent among cardiac patients and might represent risk factors for rehabilitation outcomes. The aim of this study was to investigate the role of depression and anxiety as possible independent risk factors for CR outcomes.

METHODS

The study applied a pre-post-design. The sample comprised N = 3'434 cardiac disease patients taking part in a Swiss inpatient CR center. Variables measured at the beginning (T1) and end of rehabilitation (T2) included depression and anxiety (HADS), EC, and QoL (MacNew). A path analysis was conducted.

RESULTS

Depression at T1 had a significant negative relationship with improvements in EC and in all aspects of QoL during rehabilitation. Anxiety at T1 was positively related to improvements in EC and in emotional and physical QoL. Improvements in depression during CR were positively related with improvements in all outcomes. Improvements in anxiety showed no significant association with the outcomes.

CONCLUSION

Depression and anxiety should be screened for during CR. Depression should be treated due to the negative association found with rehabilitation outcomes. Underlying mechanisms of the positive association of anxiety with rehabilitation outcomes need further investigation.

Self esteem and clinical features in a clinical sample of children with ADHD and social anxiety disorder

OBJECTIVE

In this study, we aimed to investigate self-esteem and clinical features in clinically referred children and adolescents with attention-deficit/hyperactivity disorder (ADHD) and comorbid Social Anxiety Disorder (SAD) and compare these to children and adolescents without SAD.

METHODS

One hundred and twenty child and adolescent drug-naïve outpatients (6-15 years of age) with a primary diagnosis of ADHD were included. Schedule for Affective Disorders and Schizophrenia for School Age Children-Present and Lifetime Version (K-SADS-PL), was used to evaluate ADHD and comorbidities. Parents filled in clinical and sociodemographic data form, Conners Parent Rating Scale (CPRS) and patients filled in Rosenberg Self-esteem Scale (RSES) and Çapa Social Phobia Scale for children and adolescents (ÇESFÖ).

RESULTS

Forty-six of the 120 (38.3%) children had comorbid SAD. Forty-six patients with SAD (ADHD + SAD group) and 74 patients without SAD (ADHD without SAD group) were compared in terms of the sociodemographic and clinical features, rate of psychiatric comorbidities, and rating scale scores. The rate of inattentive subtype of ADHD (p = 0.009), and social anxiety symptom scores (p < 0.001) were higher and self-esteem was lower (p < 0.001) in the ADHD + SAD group. Additionally, there was a statistically significant correlation between ÇESFÖ scores and CPRS anxiety subscale scores (r = 0.300, p = 0.001), and also Rosenberg self-esteem scale scores (r = 0.470, p < 0.001).

CONCLUSION

Children and adolescents with ADHD who had comorbid SAD may differ from ADHD patients without SAD in terms of ADHD subtype, clinical features and self-esteem.

Elementary school teachers knowledge and attitude towards attention deficit-hyperactivity disorder in Gondar, Ethiopia: a multi-institutional study

BACKGROUND

A child suffering from attention deficit hyperactivity disorder (ADHD) faces many difficulties in social as well as academic performances. School teachers' knowledge and attitude towards ADHD play a vital role in early detection and referral of the child to treatment centers. Few existing reports, however, indicate the alarming rate at which the problem is highly neglected in sub-Saharan Africa. The present study is designed to determine the knowledge, attitude, and factors that affecting elementary school teachers about ADHD.

METHODS

An institutional-based cross-sectional study design was conducted in Gondar town and other towns nearby Gondar from February 24 to March 24, 2020. Data were collected through structured self -administered questionnaires using the Knowledge of Attention Deficit Disorders Scale and ADHD-specific attitudes measurement tools. Then, it was entered into Epi-info version 7 and exported to SPSS version 20 for analysis. Bivariable and multivariate logistic regressions were fitted to identify factors associated with the knowledge and attitude of elementary school teachers. Variables having a p-value < 0.05 at 95% CI were considered statistically significant.

RESULT

Of 636 respondents, about 44.8% (95% CI 41.2, 48.4) and 84.1% (95% CI 81.0, 86.8) of elementary school teachers had good knowledge and a favorable attitude towards ADHD, respectively. Having a diploma and above (AOR = 3.028, 95% CI 1.630-5.625), reading ADHD leaflets (AOR = 2.035, 95% CI 1.391, 2.950) and search ADHD on the internet (AOR = 1.793, 95% CI 1.090, 2.950) were significantly associated with teachers knowledge to ADHD; whereas, working experience in teaching a child with ADHD (AOR = 1.852, 95% CI 1.195-2.87) and watching ADHD on mass media (AOR = 1.72, 95% CI 1.056-2.8) were positively predicts teachers attitude towards ADHD.

CONCLUSION

the proportion of teachers' knowledge towards ADHD was low; in contrast, their attitude was relatively satisfactory. Strengthening teachers' educational upgrading system, frequent and fair distribution of leaflets written to address ADHD, installation of an internet system to the schools, and continuous ADHD awareness creation programs through mass media are highly recommended.

The prevalence of attention-deficit hyperactivity disorder and its related risk factors among children at elementary school in Shahroud

BACKGROUND

Attention-deficit hyperactivity disorder (ADHD) is one of the most common reasons for visiting psychiatrists and psychologists. This study aimed to investigate the prevalence of ADHD and its related risk factors among children at elementary schools.

MATERIALS AND METHODS

This cross-sectional study focused on teachers and parents of 779 elementary students who were selected through stratified cluster random sampling; Conners Parent and Teacher Questionnaires were used to collecting data. The data were analyzed by the use of descriptive statistics (frequency and percentage), independent samples t-test, Chi-square, one-way ANOVA, and linear regression. The significant level was set at 0.05.

RESULTS

According to teachers' responses, the prevalence of ADHD among students in elementary schools was 4.4%, whereas parents reported a prevalence of 0.5%. There was a significant relationship between childhood ADHD and marital status of parents, fathers' smoking habits, previous experience of living in rural areas, children's previous history of having diseases and using the medicine, previous history of ADHD, and psychological problems in the family.

CONCLUSIONS

According to the study, teachers and parents suffer from a lack of knowledge about ADHD. Thus, the educational workshops and programs should be held for teachers, parents, and counselors to inform them about the procedures for timely diagnosis and treatment of ADHD.

Generalized anxiety disorder: Prevalence, predictors, and comorbidity in children and adolescents

Generalized anxiety disorder (GAD) is one of the most prevalent anxiety disorders among children and adolescents.

OBJECTIVES

The purpose of this study is to determine the prevalence, sociodemographic variables, and comorbidity of GAD among children and adolescents to suggest the main predictors, using an analytical cross-sectional study.

METHOD

Data were collected via a multistage random-cluster sampling method from 29,709 children and adolescents aged 6-18 years old in Iran. We used the Persian present and lifetime version of the Kiddie Schedule for Affective Disorders and Schizophrenia (K-SADS-PL). Then, we analyzed the data via descriptive analysis and multivariate logistic regression analysis methods.

RESULTS

The lifetime prevalence rate for GAD was 2.6 % (95 % Cl, 2.4%-2.8%). Overall, logistic regression analyses revealed five variables with significant unique contributions to the prediction of GAD. Significant predictors were: age, sex, mother history of psychiatric hospitalization, mother education, and residence. Participants with these risk factors were between 0.23-2.91 times more likely to present with GAD. Besides, the highest and lowest comorbidity rates of psychiatric disorder with GAD was 57.6 % and 0.3 % related to anxiety and eating disorders, respectively. Age or sex also affects the comorbidity of GAD and some mental disorders including behavioral, neurodevelopmental, elimination, and mood disorders.

CONCLUSION

This study, which was conducted in Iran, is located at the low end of the range of international estimates for GAD. Awareness of the predictors and comorbidity of GAD could be used in the prevention of GAD in children and adolescents.

ADHD symptoms in the adult general population are associated with factors linked to ADHD in adult patients

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder in children and adults. It is characterized by inappropriate levels of inattention (IA) and/or hyperactivity and impulsivity (HI). The ADHD diagnosis is hypothesized to represent the extreme of a continuous distribution of ADHD symptoms in the general population. In this study, we investigated whether factors linked to adult ADHD as a disorder are associated with adult ADHD symptoms in the general population. Our population-based sample included 4987 adults (mean age 56.1 years; 53.8% female) recruited by the Nijmegen Biomedical Study (NBS). Participants completed the Dutch ADHD DSM-IV Rating Scale for current and childhood ADHD symptoms, the Symptom Check List-90-R (SCL-90-R) anxiety subscale, and the Eysenk Personality Questionnaire (EPQR-S). Partial Spearman correlation and Hurdle negative binomial regression analysis were used to assess how age, sex, childhood ADHD symptoms, anxiety symptoms, and personality traits (neuroticism, extraversion, and psychoticism) are associated with current IA and HI symptoms. Increasing age was associated with a lower proportion of participants reporting HI symptoms and with reduced levels of HI; IA levels remained fairly stable over the age-range, but the probability of reporting IA symptoms increased throughout middle/late adulthood. Females were more likely to report IA symptoms than males. Childhood ADHD symptoms, neuroticism, and psychoticism were positively associated with current IA and HI symptoms, while extraversion had an opposite association with these symptom domains. Anxiety symptoms affected HI symptoms in females. Our results indicate that factors associated with categorical ADHD are also correlated with ADHD symptoms in the adult population.

Shorter REM latency in children with attention-deficit/hyperactivity disorder

The discrepancies in prior research about the actual sleep problems underlying attention-deficit/hyperactivity disorder (ADHD) demand more studies of children with this disorder. This study aimed to compare the subjective and objective sleep characteristics of 20 children with ADHD (DSM-IV criteria) and 20 typically developing children (aged 7-11 years). We assessed the children using sleep questionnaires and polysomnography recordings and analysed differences between the two groups using two-tailed Mann-Whitney U exact tests and Rosenthal's r as effect size measure. We also assessed associations between sleep measures and psychopathology using Spearman's correlation coefficients. No significant difference was found between the groups in almost any objective sleep variable, except for shorter REM latency in the ADHD group. Children with ADHD also showed significantly higher levels of daytime sleepiness and greater general sleep problems than control children, as reported by their parents, after discarding the primary sleep problems commonly associated with ADHD. Significant correlations were found between psychopathology and sleep measures. Our findings might support the link between narcolepsy-like sleep phenotype and ADHD. However, longitudinal research combining objective and subjective assessments should further explore the involvement of other variables, such as ADHD subtypes, medication, and comorbid symptoms in this relationship.

Sex differences in neuropsychological functioning among children with attention-deficit/hyperactivity disorder

Cognitive impairments are often reported in research on children with attention-deficit/hyperactivity disorder (ADHD). However, studies analyzing sex differences in this context are still sparse. This study aimed to compare the neuropsychological performance of boys and girls with ADHD across several cognitive domains. Verbal comprehension, perceptual reasoning, working memory, processing speed, and general cognitive performance were assessed in 240 children aged 6-17 years: 120 children (65 boys) with a clinical diagnosis of ADHD and 120 typically developing children (60 boys). Underperformance of children with ADHD compared to controls was observed in all the evaluated cognitive domains, except for verbal comprehension. Significantly lower scores in perceptual reasoning, with a medium effect size, were found in girls with ADHD relative to boys, although the sexes did not significantly differ in terms of the remaining variables. Children's ADHD subtypes did not correlate significantly with any performance measure, and no significant interaction effects between children's age and sex were noted in the results. The performance commonalities found between boys and girls with ADHD outweighed the differences, which highlights the importance of further research on cognitive dysfunction in girls with ADHD, regardless of sex differences in the prevalence of the disorder.