Prevalence of attention deficit hyperactivity disorder among children and adolescents in Spain: a systematic review and meta-analysis of epidemiological studies

Social Skills Deficits in a Virtual Environment Among Spanish Children With ADHD

OBJECTIVE

Research assessing the social skills of children with ADHD has predominantly relied upon North American samples. In addition, most existing work has been conducted using methodology that fails to use a controlled peer stimulus; such methods may be more vulnerable to cultural influence.

METHOD

We examined the social skills of 52 Spanish children (ages 8-12) with and without ADHD using a controlled Chat Room Task, which simulates a virtual social environment where peers' responses are held constant, so that participants' social skills may be assessed.

RESULTS

After statistical control of typing and reading comprehension skills, Spanish children with ADHD gave fewer prosocial comments and had greater difficulty remembering central details from the conversation between the peers, relative to comparison children.

CONCLUSION

The virtual Chat Room Task may be useful to assess social skills deficits using a controlled paradigm, resulting in the identification of common social deficiencies cross-culturally.

Gene regulatory mechanisms underlying sex differences in brain development and psychiatric disease

The sexual differentiation of the mammalian nervous system requires the precise coordination of the temporal and spatial regulation of gene expression in diverse cell types. Sex hormones act at multiple developmental time points to specify sex-typical differentiation during embryonic and early development and to coordinate subsequent responses to gonadal hormones later in life by establishing sex-typical patterns of epigenetic modifications across the genome. Thus, mutations associated with neuropsychiatric conditions may result in sexually dimorphic symptoms by acting on different neural substrates or chromatin landscapes in males and females. Finally, as stress hormone signaling may directly alter the molecular machinery that interacts with sex hormone receptors to regulate gene expression, the contribution of chronic stress to the pathogenesis or presentation of mental illness may be additionally different between the sexes. Here, we review the mechanisms that contribute to sexual differentiation in the mammalian nervous system and consider some of the implications of these processes for sex differences in neuropsychiatric conditions.

Using Brain Activation (nir-HEG/Q-EEG) and Execution Measures (CPTs) in a ADHD Assessment Protocol

Attention Deficit Hyperactivity Disorder (ADHD) is a problem that impacts academic performance and has serious consequences that result in difficulties in scholastic, social and familial contexts. One of the most common problems in the identification of this disorder relates to the apparent over diagnosis of the disorder due to the absence of global protocols for assessment. The research group of School Learning, Difficulties and Academic Performance (ADIR) from the University of Oviedo, has developed a complete protocol that suggests the existence of certain patterns of cortical activation and executive control for identifying ADHD more objectively. This protocol takes into consideration some of the hypothetical determinants of ADHD, including the relationship between activation of selected areas of the brain, and differences in performance on various aspects of executive functioning such as omissions, commissions or response times, using innovative tools of Continuous Performance Testing (based on Virtual Reality CPT and Traditional CPT) and brain activation measures (two different tools, based on Hemoencephalography- nirHEG; and Quantified Electroencephalography --Q-EEG, respectively). This model of assessment aims to provide an effective assessment of ADHD symptomatology in order to design an accurate intervention and make appropriate recommendations for parents and teachers.

Prevalence of probable Attention-Deficit/Hyperactivity Disorder symptoms: result from a Spanish sample of children

Background

The aims of our study were to: (i) determine the prevalence of children aged 4 to 6 years with probable Attention-Deficit/Hyperactivity Disorder (ADHD) symptoms in the Spanish population; and (ii) analyse the association of probable ADHD symptoms with sex, age, type of school, origin (native or foreign) and socio-economic status in these children.

Methods

This cross-sectional study included 1189 children (4 to 6 years-old) from 21 primary schools in 19 towns from the Ciudad Real and Cuenca provinces, Castilla-La Mancha region, Spain. The ADHD Rating Scales IV for parents and teachers was administered to determine the probability of ADHD. The 90th percentile cut-off was used to establish the prevalence of inattention, hyperactivity/impulsivity and combined subtype.

Results

The prevalence of children with probable ADHD symptoms was 5.4% (2.6% inattention subtype symptoms, 1.5% hyperactivity/impulsivity subtype symptoms, and 1.3% combined subtype symptoms). Children aged 4 to 5 years showed a higher prevalence of probable ADHD in the inattention subtype symptoms and in total of all subtypes than children aged 6 years, and children with low socio-economic status reported a higher prevalence of probable ADHD symptoms (each subtype and total of all of them) than those with medium and high socio-economic status.

Conclusions

Early diagnosis and an understanding of the predictors of being probable ADHD are needed to direct appropriate identification and intervention efforts. These screening efforts should be especially addressed to vulnerable groups, particularly low socio-economic status families and younger children.

ADHD Prevalence in Spanish Preschoolers: Comorbidity, Socio-Demographic Factors, and Functional Consequences

OBJECTIVE

The object was to examine the prevalence of ADHD among preschoolers, analyzing comorbidity, and the association with socio-demographic factors.

METHOD

We conducted a two-phase epidemiological study of 1,104 preschoolers aged 3 to 6 years in Catalonia, Spain. The Early Childhood Inventory-4 (ECI-4) was administered to parents and teachers. Children at risk of ADHD were assessed using open-ended face-to-face interviews and were observed in a school setting. ADHD diagnoses were based on Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) criteria.

RESULTS

The prevalence of ADHD diagnosis was 5.4%. Male sex and first-born status were risk factors for ADHD. Parents reported more symptoms (12.9%) than teachers (8.7%). Behavioral problems (odds ratio [OR] = 12, p = .001), autism spectrum disorder problems (OR = 9.5, p = .001), and obsessive-compulsive problems and tics (OR = 5.9, p = .001) were specifically related to ADHD diagnosis. Mother's health status and school achievement were lower in ADHD children.

CONCLUSION

Even at early stages of development, ADHD has high rates of comorbidity and a significant impact on school performance and family health.

Child/Adolescent's ADHD and Parenting Stress: The Mediating Role of Family Impact and Conduct Problems

Objective: The demands of parenting are usually associated with some stress, and elevated levels of stress may affect the parent-child relationships and parenting practices. This is especially the case of families where children have special needs conditions or disorders, like Attention Deficit Hyperactivity Disorder (ADHD). Method: This study examined parenting stress among mothers of children and adolescents with ADHD. The sample comprised 126 mothers of girls (36; 29%) and boys (90; 71%) aged 6-17 years old. Results: Mothers reported their own stress levels as well as the children and adolescents' variables (severity of their ADHD symptoms, conduct, and emotional problems) and family-contextual variables (negative impact on family's social life, impact on couple relationship, and perceived social support). Hierarchical multiple regression showed that (a) negative impact on social life and conduct problems were the strongest predictors of mother's stress. Bootstrap mediation analyses revealed that (b) the association between child and adolescent's ADHD and parenting stress was mediated by children's conduct problems and by negative impact on family's social life, and not by children's emotional problems nor by mother's perceived social support. The mediation analysis also suggested (c) a pathway from child/adolescent's ADHD through children's conduct problems and then through their negative impact on family's social life to mother's parenting stress. Conclusion: These results suggest that both child/adolescent's and family factors should be considered in the designing of interventions for reducing parenting stress in families of children and adolescents with ADHD.

[Associations and dissociations: agents, discourses and controversies surrounding child hyperactivity]

Attention deficit hyperactivity disorder (ADHD) generates debates and confrontations among diverse social agents with different conceptions of normality, health, the individual and the social. In this scenario of controversy, parents have tried to improve the living conditions of their children through a number of models of social participation in health. Using a qualitative ethnographic approach, fieldwork was carried out from 2013 to 2015 with the purpose of analyzing the universe of organizations regarding ADHD in Spain as well as other individual parenting initiatives with collective repercussions. The work seeks to identify the different relationships with expert knowledge in existence and the models of knowledge circulation that take place within those relationships, focusing on the way they configure discursive stances, establish collective dynamics, and develop actions. The disputed character of ADHD is evidenced in models more complex than that of the expert/layperson duality, as well as in new strategies of production and collectivization of knowledge facilitated by the Internet.

[The epidemiology of pharmacologically treated attention deficit hyperactivity disorder (ADHD) in the Region of Murcia, Spain: Differences by gender, age and location of residence]

INTRODUCTION

Attention deficit hyperactivity disorder (ADHD) is the most frequent disorder in childhood and adolescence, and is seen as a public health problem. The recommended treatment includes pharmacological and psychosocial treatment. The aim of this work was to study the changes in the prescribing of the medicines used in ADHD treatment in the Region of Murcia, as well as their socio-demographic variability.

METHOD

A retrospective observational study was conducted using the dispensing of medicines for ADHD treatment by means of prescription in the Region of Murcia from 2010 to 2014. The consumption rates were determined as defined daily doses (DDD) per thousand inhabitants/day (DHD), stratified by gender and age. The reasons for prevalence of treatment by gender were also determined by comparing male and female consumption rates.

RESULTS

The consumption of medicines for ADHD treatment had almost doubled in the period studied, from 5.58 DHD and 3.39 DHD in 2010 to 9.34 DHD and 6.71 DHD in 2014, for the age range of 10-14 and 15-19, respectively. Boys from 10-14 showed the highest consumption rates, showing a high geographical variability with less consumption in rural areas.

CONCLUSION

The results showed a large increase in the use of medicines for ADHD treatment in the Region of Murcia, although the consumption rates are still lower than in other Autonomous Communities or neighbouring countries. A wide geographical variability was found, with a higher consumption in adolescents from urban areas.

Prevalence of Attention-Deficit/Hyperactivity Disorder and its Comorbidity among Korean Children in a Community Population

The aim of this study was to determine the prevalence of attention deficit hyperactivity disorders (ADHD) in children according to socio-demographic factors and the distribution of ADHD subtypes in a community in Korea. A screening survey using the Korean version of ADHD Rating Scale (K-ARS) was conducted between 2007 and 2008, and clinical interviews by a pediatric psychiatrist were performed for selected children between 2009 and 2010. A total of 49,573 elementary school students, between ages of 7 and 12, constituted the target population, among which 38,365 students (77.2%) and respective parents gave consent to participate. Of the participants, 200 screened children were clinically examined to confirm the diagnosis of ADHD. We estimated the prevalence of ADHD and its comorbidity in the population, after adjusting for nonresponse and nonparticipation. The prevalence of ADHD was 11.7% in boys and 5.2% in girls, with an overall prevalence of 8.5%. The combined type of inattentive and hyperactive was the most frequent at 4.7% of the whole population. Children were more likely to have ADHD if their parents were separated and had less education. Most commonly combined comorbidity was autism spectrum disorder (ASD) (10.1%). The prevalence of ADHD in the school-aged population is an essential information for improving the quality of public health mental services for evaluation and treatment of ADHD.

Association Between Age of Beginning Primary School and Attention Deficit Hyperactivity Disorder

OBJECTIVE

In April 2012, the Turkish national education system was modified, and the compulsory school age of entry (first grade) was redefined as a minimum of 60 months and a maximum of 66 months (replacing the former minimum criterion of 72 months). In this study, we hypothesized that students starting school before 72 months (the previous age standard for the first grade) may experience (1) a greater number of symptoms of attention deficit hyperactivity disorder (ADHD) and (2) lower functioning in social, behavioral, and academic domains.

METHOD

We performed a cross-sectional community-based study in the first and second grades of all primary schools (4356 students) located in the Kadıköy county of Istanbul, Turkey. Teachers completed Swanson, Nolan, and Pelham version IV and Conners' Teacher's report forms for symptoms of ADHD, the Perceived Competence Scale for functioning, and a sociodemographic questionnaire.

RESULTS

Among first graders, the group that began primary school before the age of 72 months had a higher ADHD prevalence than both of the groups that began primary school between the ages of 72 to 77 months and 78 to 83 months (p < .001 for both groups). ADHD symptoms diminished and academic, social, and behavioral functioning improved with age for the first and second grade students.

CONCLUSION

The probability of displaying ADHD symptoms (and caseness) is greater among the "earlier" beginners, whereas the "conventional" classmates exhibited better academic, social, and behavioral functioning.

Psychometric properties of the Conners-3 and Conners Early Childhood Indexes in a Spanish school population

Ba#ckground/Obje#ctive: To examine the psychometric properties of the Conners 3 ADHD Index (Conners 3 AI) and the Conners Early Children Global Index (Conners ECGI) parents' form (PF) and teachers' form (TF) in Spanish schoolers. Method: Two-phase cross-sectional study. In the first phase, information was gathered from teachers (n = 1,796) and parents (n = 882) of 4-5 and 10-11 year-old children. In the second phase (n = 196), children at risk of ADHD and controls were individually assessed. Results: The results confirmed the two-factor structure of the Conners 3 ADHD Index, which contains hyperactive-impulsive and inattentive symptoms, and the two-factor structure of the Conners ECGI PF, consisting of emotional lability and restless-impulsive symptoms. In contrast with the original version, the Conners ECGI TF presented an additional inattentive factor. Moderate-to-high rates of evidence of convergent validity with Child Behavior Checklist and Kiddie-Schedule for Affective Disorders & Schizophrenia, and evidence of external validity (academic achievement) were found. Scores were significantly higher in boys than in girls, for both indexes. Raw scores corresponding to clinical T-scores were higher than the original version. Conclusions: The Conners indexes may be considered reliable and valid instruments for detecting ADHD symptoms in Spanish populations.

Variability and trends in the consumption of drugs for treating attention-deficit/hyperactivity disorder in Castile-La Mancha, Spain (1992-2015)

INTRODUCTION

Attention-deficit/hyperactivity disorder (ADHD) is one of the most common behavioural disorders of childhood; its prevalence in Spain is estimated at 5-9%. Available treatments for this condition include methylphenidate, atomoxetine, and lisdexamfetamine, whose consumption increases each year.

MATERIAL AND METHODS

The prevalence of ADHD was estimated by calculating the defined daily dose per 1,000 population per day of each drug and the total doses (therapeutic group N06BA) between 1992 and 2015 in each of the provinces of Castile-La Mancha (Spain). Trends, joinpoints, and annual percentages of change were analysed using joinpoint regression models.

RESULTS

The minimum prevalence of ADHD in the population of Castile-La Mancha aged 5 to 19 was estimated at 13.22 cases per 1,000 population per day; prevalence varied across provinces (p<.05). Overall consumption has increased from 1992 to 2015, with an annual percentages of change of 10.3% and several joinpoints (2000, 2009, and 2012). methylphenidate represents 89.6% of total drug consumption, followed by lisdexamfetamine at 8%.

CONCLUSIONS

Analysing drug consumption enables us to estimate the distribution of ADHD patients in Castile-La Mancha. Our data show an increase in the consumption of these drugs as well as differences in drug consumption between provinces, which reflect differences in ADHD management in clinical practice.

Is There a Female Protective Effect Against Attention-Deficit/Hyperactivity Disorder? Evidence From Two Representative Twin Samples

OBJECTIVE

Attention-deficit/hyperactivity disorder (ADHD) is more frequent in males than in females. The "female protective effect" posits that females undergo greater exposure to etiological factors than males in order to develop ADHD, leading to the prediction that relatives of females with ADHD will display more ADHD behaviors. We thus tested whether cotwins of females displaying extreme ADHD traits would display more ADHD traits than cotwins of males displaying extreme ADHD traits.

METHOD

Parents of approximately 7,000 pairs of nonidentical twins in Sweden, and approximately 4,000 pairs of twins in England and Wales, completed dimensional assessments of ADHD traits. Probands were selected on the basis of scoring within the highest 10% of the distribution in each sample. Dimensional scores of cotwins of probands, as well as the categorical recurrence rate, were investigated by proband sex.

RESULTS

Cotwins of female probands displayed higher mean ADHD trait scores (mean = 0.62-0.79) than cotwins of male probands (mean = 0.38-0.55) in both samples. This trend was significant in the Swedish sample (p < .01) and when the 2 samples were merged into a single, larger sample (p < .001). When the samples were merged, there was also a significant association between proband sex and cotwin's categorical status, with more cotwins of female probands also being probands than cotwins of male probands.

CONCLUSION

These findings support a female protective effect against ADHD behaviors, suggesting that females require greater exposure to genetic and environmental factors associated with ADHD in order to develop the condition.

Sex differences in neurodevelopmental and neurodegenerative disorders: Focus on microglial function and neuroinflammation during development

Several neurological conditions are associated with sex differences in prevalence or outcome. For example, autism predominantly affects boys, depression is more common in women, Parkinson's disease more common in men, and multiple sclerosis in women. In the case of stroke, women have a less favorable outcome and suffer from a more precipitous drop in health status compared to men. As a result, treatment of such diseases is difficult and yields variable results. Despite this, sex is rarely considered when making treatment decisions. The mechanisms underlying sex differences in disease progression are not well understood, however a strong link exists between different inflammation states of men and women and their propensity to develop certain diseases. As neuroinflammation is an important component of pathophysiology in many neurological conditions, it can be speculated that any changes in the state of inflammation in the brain during normal development can potentially lead to an increase in susceptibility to neurological and neurodegenerative diseases. Microglia play a crucial role in onset and modulation of inflammation and thus sex differences in microglial function could explain, at least in part, differences observed in susceptibilities and outcomes of neurological disorders in men and women. Understanding the mechanisms behind sex differences could help develop more targeted therapy with higher success rate, especially in diseases where sex differences are most prominent.

Knowledge and Attitude of Parents of Children With Attention Deficit Hyperactivity Disorder Towards the Illness

Background

The knowledge and attitude of parents about attention deficit hyperactivity disorder (ADHD) is a public health issue in which management and rehabilitation approaches may be influenced.

Objectives

The current study aimed to evaluate the knowledge and attitude of the parents of children with ADHD towards this disorder in Tabriz, Iran.

Materials and Methods

The current cross-sectional study evaluated 295 parents of children and adolescents with ADHD referred to psychiatric clinics of Tabriz University of Medical Sciences. The subjects were diagnosed based on Kiddie schedule for affective disorders and schizophrenia for school-aged children (K-SADS) and recruited according to a convenience sampling method in the first five months of 2014. The parents’ knowledge and attitude towards ADHD was studied by a researcher-made questionnaire.

Results

The overall knowledge of parents was 66% in which 76.72% were aware of related signs and symptoms and 43.38% were able to identify the aberrations. Meanwhile, 44.62% of the parents knew the etiology and 54.75% had information about treatment strategies. In addition, 33.55%, 37.91%, 25.52% were aware of ADHD consequences, diagnosis and prevalence dimensions, respectively. Moreover, 82.72% of the parents had a positive attitude towards ADHD. A positive correlation was found between parents’ attitude towards ADHD and their overall knowledge (identification, etiology, treatment, consequences and prevalence dimensions), ranging from 0.12 to 0.36 (P < 0.50). Age, gender, and place of residence did not have a correlation with parents’ knowledge and attitude towards ADHD. Parent’s education level only had a positive correlation with the knowledge of symptoms, with a value of 0.19 (P < 0.01). Parents with a higher overall knowledge, knowledge of ADHD symptoms, and prevalence rates accepted combination therapy (P < 0.05).

Conclusions

While the overall knowledge of parents regarding ADHD was favorable, they were mostly unable to identify the aberrations in children with ADHD. These results may help practitioners address pitfalls in parent management training programs.

Traffic-Related Air Pollution, Noise at School, and Behavioral Problems in Barcelona Schoolchildren: A Cross-Sectional Study

BACKGROUND

The available evidence of the effects of air pollution and noise on behavioral development is limited, and it overlooks exposure at schools, where children spend a considerable amount of time.

OBJECTIVE

We aimed to investigate the associations of exposure to traffic-related air pollutants (TRAPs) and noise at school on behavioral development of schoolchildren.

METHODS

We evaluated children 7-11 years of age in Barcelona (Catalonia, Spain) during 2012-2013 within the BREATHE project. Indoor and outdoor concentrations of elemental carbon (EC), black carbon (BC), and nitrogen dioxide (NO2) were measured at schools in two separate 1-week campaigns. In one campaign we also measured noise levels inside classrooms. Parents filled out the strengths and difficulties questionnaire (SDQ) to assess child behavioral development, while teachers completed the attention deficit/hyperactivity disorder criteria of the DSM-IV (ADHD-DSM-IV) list to assess specific ADHD symptomatology. Negative binomial mixed-effects models were used to estimate associations between the exposures and behavioral development scores.

RESULTS

Interquartile range (IQR) increases in indoor and outdoor EC, BC, and NO2 concentrations were positively associated with SDQ total difficulties scores (suggesting more frequent behavioral problems) in adjusted multivariate models, whereas noise was significantly associated with ADHD-DSM-IV scores.

CONCLUSION

In our study population of 7- to 11-year-old children residing in Barcelona, exposure to TRAPs at school was associated with increased behavioral problems in schoolchildren. Noise exposure at school was associated with more ADHD symptoms.

CITATION

Forns J, Dadvand P, Foraster M, Alvarez-Pedrerol M, Rivas I, López-Vicente M, Suades-Gonzalez E, Garcia-Esteban R, Esnaola M, Cirach M, Grellier J, Basagaña X, Querol X, Guxens M, Nieuwenhuijsen MJ, Sunyer J. 2016. Traffic-related air pollution, noise at school, and behavioral problems in Barcelona schoolchildren: a cross-sectional study. Environ Health Perspect 124:529-535; http://dx.doi.org/10.1289/ehp.1409449.

Physical activity intervention (Movi-Kids) on improving academic achievement and adiposity in preschoolers with or without attention deficit hyperactivity disorder: study protocol for a randomized controlled trial

BACKGROUND

The prevention of obesity and improvement of academic achievement in children are concerns of industrialized societies. Obesity has been associated with psychological disorders, including attention deficit hyperactivity disorder, whose prevalence has been estimated at 6.8 % in Spanish children and adolescents. It is known that physical activity is positively related to academic achievement and negatively related to the risk of obesity in children. However, studies to test the effectiveness of physical activity interventions in improving academic achievement in preschool children are scarce and have some weaknesses that threaten their validity. Moreover, very few studies have examined their effectiveness in improving symptoms of attention deficit hyperactivity disorder. This paper outlines a two-year multidimensional preschool intervention (Movi-Kids) aimed at preventing obesity and improving academic achievement in children with or without attention deficit hyperactivity disorder.

METHODS/DESIGN

Twenty-one schools from Ciudad Real and Cuenca, Spain, were randomized to intervention and control groups. In the first academic year, children in the third grade of preschool and the first grade of primary school in the intervention group received the Movi-Kids intervention. In the second academic year, schools were crossed over to the other group. The intervention included children, parents and teachers, and the school environment, and consisted of: (i) three hour-long sessions of recreational non-competitive physical activity after school, weekly, (ii) educational materials for parents and teachers addressing sedentary lifestyle risks and (iii) playground modifications to promote physical activity during breaks. Primary outcome measures of this study were academic achievement (intelligence, cognition, memory, attention and perception), assessed by the Battery of General and Differential Aptitudes, and adiposity measures (body mass index, waist circumference, triceps skinfold thickness and body fat percentage). Secondary outcome measures were: attention deficit hyperactivity disorder risk, motor skills, health-related quality of life and sleep quality. These variables will all be measured in both groups at baseline and at the end of the first and second academic years.

DISCUSSION

It seems reasonable that an intervention to promote physical activity based on playground games will be useful for simultaneously improving academic achievement and controlling obesity.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01971827 .

Diagnosis of children's attention deficit hyperactivity disorder (ADHD) and its association with cytomegalovirus infection with ADHD: a historical review

As the most common mental disorder identified in children and teenagers, attention deficit hyperactivity disorder (ADHD) affects millions of children and their families, making it a critical health issue worldwide. This article reviewed the historical opinions about the diagnosis of ADHD and defined different subtypes of this disorder. It also summarized the current diagnostic criteria and available medications. After re-visiting the etiology of ADHD in the sense of both genetic and environment factors, it was further hypothesized that viral infection might be involved in ADHD pathogenesis. Human cytomegalovirus (HCMV) infection may be associated with ADHD, although both clinical observations and animal studies need to be performed for validation.

An evaluation of variation in published estimates of schizophrenia prevalence from 1990─2013: a systematic literature review

BACKGROUND

There is a lack of consistency in findings across studies on the prevalence of schizophrenia, and no recent systematic review of the literature exists. The purpose of this study is to provide an updated systematic review of population-based prevalence estimates and to understand the factors that could account for this variation in prevalence estimates.

METHODS

MEDLINE, Embase, and PsycInfo databases were searched for observational studies describing schizophrenia prevalence in general populations from 2003-2013 and supplemented by studies from a prior review covering 1990-2002. Studies reporting prevalence estimates from specialized populations such as institutionalized, homeless, or incarcerated persons were excluded. Prevalence estimates were compared both across and within studies by factors that might contribute to variability using descriptive statistics.

RESULTS

Sixty-five primary studies were included; thirty-one (48 %) were from Europe and 35 (54 %) were conducted in samples of ≥50,000 persons. Among 21 studies reporting 12-month prevalence, the median estimate was 0.33 % with an interquartile range (IQR) of 0.26 %-0.51 %. The median estimate of lifetime prevalence among 29 studies was 0.48 % (IQR: 0.34 %-0.85 %). Prevalence across studies appeared to vary by study design, geographic region, time of assessment, and study quality scores; associations between study sample size and prevalence were not observed. Within studies, age-adjusted estimates were higher than crude estimates by 17 %-138 %, the use of a broader definition of schizophrenia spectrum disorders compared to schizophrenia increased case identification by 18 %-90 %, identification of cases from inpatient-only settings versus any setting decreased prevalence by 60 %, and no consistent trends were noted by differing diagnostic criteria.

CONCLUSIONS

This review provides updated information on the epidemiology of schizophrenia in general populations, which is vital information for many stakeholders. Study characteristics appear to play an important role in the variation between estimates. Overall, the evidence is still sparse; for many countries no new studies were identified.

Effect of adenotonsillectomy on ADHD symptoms of children with adenotonsillar hypertrophy and sleep disordered breathing

BACKGROUND

Adenotonsillar hypertrophy is the most common etiologic agent for the obstruction of the upper airways in children, which might be associated with attention-deficit hyperactivity disorder (ADHD), one of the most common psychiatric disorders of childhood. Despite the concurrence of these two conditions, i.e., obstruction of the airways and ADHD, no exact etiologic relationship has been established between adenotonsillectomy (AT) and ADHD symptoms. This study was undertaken to evaluate the effect of AT on the ADHD symptoms in children with adenotonsillar hypertrophy and sleep disordered breathing (SDB).

METHODS

The design of the present study consisted of pre-test and post-test, followed by post hoc tests. Fifty-three children aged 3-12 were included in this study, selected from those referring to the Pediatric Hospital of Tabriz University of Medical Sciences, with SDB, adenotonsillar hypertrophy and ADHD based on DSM-IV criteria, by availability of the subjects undergoing adenotonsillectomy after evaluation of the severity of ADHD symptoms. The scores of ADHD symptoms were evaluated before AT and at 3- and 6-month postoperative intervals based on Conner's Parent Rating Scale-Revised (CPRS-R) Questionnaire. Repeated-measures ANOVA and Fisher's exact test were used for data analysis.

RESULTS

AT resulted in a significant decrease in the severity of ADHD symptoms (oppositional behavior, cognitive disorders, inattention, hyperactivity and ADHD index) at 3- and 6-month postoperative intervals (P<0.001), with more significant decreases at 6-month postoperative interval compared to 3-month interval (P<0.001).

CONCLUSIONS

Based on the results of this pilot study, AT in children with SDB associated with ADHD resulted in a significant decrease in the severity of ADHD symptoms.

Anxiety, Decision Conflict, and Health in Caregivers of Children with ADHD: A Survey

The purpose of this study was to test a theoretical model to determine the effect of caregiver anxiety and decision conflict on the health of caregivers of children with ADHD. Cross-sectional analyses were conducted on data derived from caregivers (aged 24-70). Participants completed the Decision Conflict Scale, the Zung Anxiety Scale, the Duke Health Profile, and a demographic form. A path model that fit well indicated that anxiety and decision conflict had direct and indirect effects on the caregivers' health. Future study is needed to clarify factors contributing to uncertainty and to decrease emotional symptoms for caregivers, thus promoting their mental health.

Attention-deficit/hyperactivity disorder treatment: what are the long-term cardiovascular risks?

INTRODUCTION

This drug safety review provides an update on the long-term cardiovascular risks of therapeutic stimulant class medication for children and adults with attention-deficit/hyperactivity disorder (ADHD).

AREAS COVERED

Relevant literature on the long-term (defined as ≥ 12 months) cardiovascular effects of stimulant class medications for ADHD was sought using PubMed searches for clinical literature, epidemiological reports, as well as reviews of post-marketing data and clinical guidelines/consensus statements. Comparison was made to the non-stimulant atomoxetine.

EXPERT OPINION

Long-term cardiovascular risks of stimulants for healthy children and adults with ADHD are limited to minor mean elevations in blood pressure (≤ 7 mmHg) and heart rate (≤ 10 bpm). In a sizeable minority of individuals these elevations are greater and/or reach a clinical threshold. Subjective complaints may also be anticipated during long-term treatment, yet without an increase in serious cardiac outcomes above background rates per age. Future research is needed on possible latent or cumulative cardiovascular risks in healthy individuals, as well as the longer-term cardiovascular safety in vulnerable populations.

Postnatal arsenic exposure and attention impairment in school children

Over the last few decades there has been an increased concern about the health risks from exposure to metallic trace elements, including arsenic, because of their potential neurotoxic effects on the developing brain. This study assessed whether urinary arsenic (UA) levels are associated with attention performance and Attention-Deficit/Hyperactivity Disorder (ADHD) in children living in an area with high industrial and mining activities in Southwestern Spain. A cross-sectional study was conducted on 261 children aged 6-9 years. Arsenic levels were determined in urine samples. Attention was measured by using 4 independent tools: a) tests from the Behavioral Assessment and Research System (BARS) designed to measure attention function: Simple Reaction Time Test (RTT), Continuous Performance Test (CPT) and Selective Attention Test (SAT); b) AULA Test, a virtual reality (VR)-based test that evaluates children's response to several stimuli in an environment simulating a classroom; c) Child Behavior Checklist (CBCL), administered to parents; and d) Teacher's Report Form (TRF), administered to teachers. Multivariate linear and logistic regression models, adjusted for potential confounders, were used to estimate the magnitude of the association between UA levels and attention performance scores. Higher UA levels were associated with an increased latency of response in RTT (β = 12.3; 95% confidence interval (CI): 3.5-21.1) and SAT (β = 3.6; 95% CI: .4-6.8) as well as with worse performance on selective and focalized attention in the AULA test (β for impulsivity = .6; 95% CI: .1-1.1; β for inattention = .5; 95% CI: .03-1.0). A dose-response relationship was observed between UA levels and inattention and impulsivity scores. In contrast, results from the CBCL and TRF tests failed to show a significant association with UA levels. In conclusion, UA levels were associated with impaired attention/cognitive function, even at levels considered safe. These results provide additional evidence that postnatal arsenic exposure impairs neurological function in children.

Comparative efficacy, acceptability, and tolerability of dexmethylphenidate versus placebo in child and adolescent ADHD: a meta-analysis of randomized controlled trials

BACKGROUND

The efficacy of dexmethylphenidate (d-MPH) has been proven in the treatment of children and adolescents with attention-deficit hyperactivity disorder (ADHD).

OBJECTIVE

The aim of this systematic review is to determine the efficacy, acceptability, and tolerability of d-MPH in child and adolescent ADHD.

METHODS

The searches of SCOPUS, MEDLINE, CINAHL, and Cochrane Controlled Trials Register were performed in February 2015. All randomized controlled trials of d-MPH versus placebo that were performed in children and adolescents with ADHD up to 18 years of age were included in the study. The efficacy was measured by using the pooled mean-endpoint or mean-changed scores of ADHD rating scales and the response rate. Acceptability and tolerability were measured by using the pooled rates of overall discontinuation and discontinuation due to adverse events, respectively.

RESULTS

A total of 1,124 children and adolescents diagnosed as having ADHD were included in this review. In a laboratory school setting, the pooled mean-change and mean-endpoint scores in the d-MPH-treated group were significantly greater than those of the placebo-treated group with standardized mean difference (95% confidence interval [CI]) of -1.20 (-1.73, -0.67), I (2)=95%. Additionally, the pooled mean-changed scores of the ADHD rating scales for teachers and parents in the d-MPH-treated group were significantly greater than that of the placebo-treated group with weighted mean difference (95% CI) of -13.01 (-15.97, -10.05), I (2)=0% and (95% CI) of -12.99 (-15.57, -10.42), I (2)=0%, respectively. The pooled response rate in the d-MPH-treated groups had a significance higher than that of the placebo-treated group. The rates of pooled overall discontinuation and discontinuation due to adverse events between the two groups were not significantly different.

CONCLUSION

Based on the findings in this review, it can be concluded that d-MPH medication is efficacious and tolerable in child and adolescent ADHD. However, the acceptability of d-MPH is no greater than that of the placebo. Further systematic studies may confirm these findings.

Green and blue spaces and behavioral development in Barcelona schoolchildren: the BREATHE project

BACKGROUND

Green spaces have been associated with improved mental health in children; however, available epidemiological evidence on their impact on child behavioral development is scarce.

OBJECTIVES

We investigated the impact of contact with green spaces and blue spaces (beaches) on indicators of behavioral development and symptoms of attention deficit/hyperactivity disorder (ADHD) in schoolchildren.

METHODS

This study was based on a sample of 2,111 schoolchildren (7-10 years of age) from 36 schools in Barcelona in 2012. We obtained data on time spent in green spaces and beaches and Strengths and Difficulties Questionnaires (SDQ) from parents, and ADHD/DSM-IV questionnaires from teachers. Surrounding greenness was abstracted as the average Normalized Difference Vegetation Index (NDVI) in buffers of 100 m, 250 m, and 500 m around each home address. Proximity to green spaces was defined as living within 300 m of a major green space (≥ 0.05 km2). We applied quasi-Poisson mixed-effects models (with school random effect) to separately estimate associations between indicators of contact with green spaces and SDQ and ADHD total and subscale scores.

RESULTS

We generally estimated beneficial associations between behavioral indicators and longer time spent in green spaces and beaches, and with residential surrounding greenness. Specifically, we found statistically significant inverse associations between green space playing time and SDQ total difficulties, emotional symptoms, and peer relationship problems; between residential surrounding greenness and SDQ total difficulties and hyperactivity/inattention and ADHD/DSM-IV total and inattention scores; and between annual beach attendance and SDQ total difficulties, peer relationship problems, and prosocial behavior. For proximity to major green spaces, the results were not conclusive.

CONCLUSION

Our findings support beneficial impacts of contact with green and blue spaces on behavioral development in schoolchildren.

Sex differences in attention Deficit Hyperactivity Disorder: candidate genetic and endocrine mechanisms

Attention Deficit Hyperactivity Disorder (ADHD) is a developmental condition characterised by severe inattention, pathological impulsivity and hyperactivity; it is relatively common affecting up to 6% of children, and is associated with a risk of long-term adverse educational and social consequences. Males are considerably more likely to be diagnosed with ADHD than females; the course of the disorder and its associated co-morbidities also appear to be sensitive to sex. Here, I discuss fundamental biological (genetic and endocrine) mechanisms that have been shown to, or could theoretically, contribute towards these sexually dimorphic phenomena. Greater understanding of how and why the sexes differ with respect to ADHD vulnerability should allow us to identify and characterise novel protective and risk factors for the disorder, and should ultimately facilitate improved diagnosis, prognosis and treatment.

The Link between Peer Relations, Prosocial Behavior, and ODD/ADHD Symptoms in 7-9-Year-Old Children

Oppositional defiant disorder (ODD) and attention-deficit/hyperactivity disorder (ADHD) are characterized by symptoms that hinder successful positive interaction with peers. The main goal of this study was to examine if the presence of symptoms of ODD and ADHD affects the relationship between positive social behavior and peer status found in 7–9-year-old children who show symptoms typical of ADHD and/or ODD. Furthermore, the possible interaction with sex was investigated. We used data collected in the first wave of The Bergen Child Study of mental health (BCS), a prospective longitudinal total population study of children's developmental and mental health. The target population consisted of children in the second to the fourth, in all public, private, and special schools in Bergen, Norway, in the fall of 2002 (N = 9430). All 79 primary schools in Bergen participated in the study. Both teacher (8809 complete cases) and parent (6253 complete cases) report were used in the analyses. ADHD and ODD scores were estimated using the Swanson Noland and Pelham rating scale version IV (SNAP-IV), and peer problems and prosocial behavior were assessed using the Strengths and Difficulties Questionnaire (SDQ). We replicated the relationship between peer problems and prosocial behavior found previously in typically developing children. Our results showed that the relationship between peer problems and prosocial behavior became weaker as the ODD symptoms increased in number and severity. For ADHD this effect was only found in the teacher report of the children. A sex effect for ODD symptoms was found only using the parent report: boys with ODD symptoms showed less prosocial behavior than girls with similar levels of ODD symptoms. Since this effect was not found using the teacher data, it may imply a situational effect (school/home) for girls with high levels of ODD. The moderator effect of ODD/ADHD was comparable for boys and girls. Our findings suggest that even if children with ADHD/ODD symptoms have the opportunity to practice their social skills in peer relationships, this is not necessarily accompanied by an increase in prosocial behavior.

Globalization and cognitive enhancement: emerging social and ethical challenges for ADHD clinicians

Globalization of ADHD and the rise of cognitive enhancement have raised fresh concerns about the validity of ADHD diagnosis and the ethics of stimulant drug treatment. We review the literature on these two emerging phenomena, with a focus on the corresponding social, scientific and ethical debates over the universality of ADHD and the use of stimulant drug treatments in a global population of children and adolescents. Drawing on this literature, we reflect on the importance of ethically informed, ecologically sensitive clinical practices in relation to ADHD diagnosis and treatment.

Prevalence and diagnostic stability of ADHD and ODD in Turkish children: a 4-year longitudinal study

BACKGROUND

This study was designed to assess the prevalence of Attention-Deficit/Hyperactivity Disorder (ADHD) and Oppositional Defiant Disorder (ODD) in a representative sample of second grade students from a country in a region where no previous rates are available (Turkey). The second aim is to evaluate the differences in ADHD and ODD prevalence rates among four different waves with one-year gap in reassessments.

METHOD

Sixteen schools were randomly selected and stratified according to socioeconomic classes. The DSM-IV Disruptive Behavior Disorders Rating Scale (T-DSM-IV-S) was delivered to parents and teachers for screening in around 1500 children. Screen positive cases and matched controls were extensively assessed using the K-SADS-PL and a scale to assess impairment criterion. The sample was reassessed in the second, third and fourth waves with the same methodology.

RESULTS

The prevalence rates of ADHD in the four waves were respectively 13.38%, 12.53%, 12.22% and 12.91%. The ODD prevalence was found to be 3.77% in the first wave, 0.96% in the second, 5.41% in the third and 5.35% in the fourth wave. Mean ODD prevalence was found to be 3.87%.

CONCLUSIONS

The prevalence rates of ADHD in the four waves were remarkably higher than the worldwide pooled childhood prevalence. ADHD diagnosis was quite stable in reassessments after one, two and three years. A mean ODD prevalence consistent with the worldwide-pooled prevalence was found; but diagnostic stability was much lower compared to ADHD.