Risk Factors For Attention-deficit/hyperactivity Disorder Research Articles

Dietary Profiles, Nutritional Biochemistry Status, and Attention-deficit/hyperactivity Disorder: Path Analysis for a Case-control Study (P18-106-19)

ObjectivesStudies suggested that attention-deficit/hyperactivity disorder (ADHD) is associated with multiple dietary factors. Earlier studies addressed issues related to dietary allergens and toxicants. Recent attention has turned to nutrient imbalance resulted from unhealthy dietary habit. This study aims to investigate dietary and nutritional biochemistry profiles of ADHD and to explore their potential relationship by path analysis. MethodsWe enrolled 216 children with ADHD and 216 age-, height- and gender-matched controls from 31 elementary schools in Taiwan. Dietary intake of the participants was assessed using food frequency questionnaire (FFQ). Fasting blood samples were collected to determine the serum levels of multiple nutritional markers, including several potential vitamins, minerals, and fatty acids. Moreover, we employed a structural equation model (SEM) to link diet, nutritional markers and ADHD. ResultsCompared to healthy control, ADHD children had significantly lower serum levels of vitamin B12, folate, vitamin B6, ferritin concentration, and monounsaturated fatty acids (MUFA), but higher levels of serum saturated fatty acids (SFA), n-6/n-3 fatty acid ratio, and inorganic phosphorous concentration (Table 1). Children with ADHD had more intakes of nutrient-poor foods such as high sugar and high fat foods, and had less intakes of vegetable, fruit, protein-rich foods than their counterpart (Table 2). SEM analysis showed that the poor nutritional biochemistry profiles linked the association between unhealthy dietary patterns and ADHD (Figure 1). ConclusionsWe found that lower serum levels of B-vitamins and imbalanced mineral and fatty acid distributions were risk factors of ADHD and path analysis suggests that unhealthy dietary pattern may be a predecessor of the poor nutritional biochemistry status. Managing diet and nutrition conditions should be trialed and considered among methods to improve ADHD symptoms in children. Funding SourcesNational Science Council of Taiwan R.O.C.; Academia Sinica. Supporting Tables, Images and/or Graphs▪▪▪

The Association between Lead and Attention-Deficit/Hyperactivity Disorder: A Systematic Review.

The etiology of Attention-Deficit/Hyperactivity Disorder (ADHD) is complex and multifactorial. Although the development of ADHD symptoms remains to be elucidated, in recent years, epigenetic processes have emerged as candidate mechanisms. Lead is one of the most dangerous environmental pollutants, and it is suspected to be associated with ADHD. The aim of the present study was to review the epidemiological literature currently available on the relation between lead exposure and the diagnosis of ADHD. The PubMed and EMBASE databases were searched from 1 July 2018 up to 31 July 2018. The authors included observational studies (cohort, case–control and cross-sectional studies) published in English carried out on children within the last 5 years, measuring lead exposure and health outcomes related to ADHD. Seventeen studies met the inclusion criteria: 5 of these studies found no association between lead exposure and ADHD whereas the remaining 12 studies showed positive associations, even though not all of them were homogeneous in terms of exposure periods considered or ADHD diagnosis. To conclude, the evidence from the studies allowed us to establish that there is an association between lead and ADHD and that even low levels of lead raise the risk. However, there is still a lack of longitudinal studies about the relationship between lead exposure and the development of ADHD. Given the potential importance for public health, further research that includes the entire potential risk factors for ADHD in children must be encouraged.

Pediatric Attention-Deficit/Hyperactivity Disorder in Louisiana: Trends, Challenges, and Opportunities for Enhanced Quality of Care.

Background: Attention-deficit/hyperactivity disorder (ADHD) is a common pediatric condition with significant developmental, social, educational, and safety implications. The American Academy of Pediatrics has developed guidelines to support quality care of children with ADHD, but studies demonstrate that the guidelines are variably followed.Methods: This review highlights patterns of diagnosis and treatment of children with ADHD nationally and in Louisiana and provides examples of system- and practice-level opportunities to improve adherence to quality standards.Results: Possible contributors to the higher prevalence of ADHD and medication use in Louisiana compared to the nation are specialty workforce shortages, factors in the educational system, and factors associated with race and geography. Innovative system approaches have been developed to address workforce shortages and training limitations. Practice-level innovations include improving the use of validated measures, offering adequate scheduling, and identifying relevant resources and sharing the information with families.Conclusion: Despite the availability of evidence-based recommendations and resources, significant opportunities exist to provide enhanced ADHD care at the primary care level, especially in Louisiana where the high prevalence of some risk factors for ADHD and the high rates of ADHD and medication prescriptions have been noted nationally and at the state level. Attention to these factors can potentially help address these disproportionalities. Additionally, innovative models of training and collaboration in pediatrics are imperative. Pediatric clinicians, mental health providers, and families can work together to increase awareness about the needs of children and families affected by ADHD in medical, educational, and policy arenas and move the system forward for children.

Emerging Evidence For Overlap of ADHD Genetic Risk Factors With Those of Other Psychiatric Illnesses

This study is presented on behalf of the iPSYCH-Broad ADHD working group, the PGC ADHD working group and the PGC MDD working group.Earlier studies have shed light on the individually unique and shared genetic risk architecture of Attention Deficit Hyperactivity Disorder(ADHD), autism spectrum disorder (ASD), and major depressive disorder (MDD). This involved single trait and cross-disorder genome-wide association studies (GWAS) as well as studies targeted at estimating the degree of genetic variation within and covariation between disorders. Especially for ADHD (but also for ASD) these analyses were potentially biased due to availability of only small samples when compared to other (adult onset) disorders in the analyses. Moreover, the identification of shared risk loci for ADHD with other disorders was likely hindered by the very same limitation. Others and we have recently performed the largest GWASs to date for ADHD (~20k cases), ASD (~18k cases), and MDD (~130k cases). These studies identified numerous genome-wide significant risk loci for the individual disorders and therefore opened the door for reliable estimation of genetic covariation and cross-phenotype association studies that have enough power to detect shared risk loci. This is of interest as comorbidity with these disorders is common in patients with ADHD and identification of shared risk loci might open the door for a better understanding of disease etiology as well as treatment options and prevention. In a first step, we calculated the genetic correlation (rG) between ADHD, ASD, and MDD and found rGs of 0.35 for ADHD/ASD and 0.42 for ADHD/MDD with an rG of 0.44 for ASD and MDD. In a second step, we performed cross-phenotype GWAS analyses for the ADHD/ASD and ADHD/MDD pairs. We identified 8 regions with genome-wide significant SNPs, amongst others harboring the hostgene of miR-9, MANBA, and NUDT12 as shared risk factors for ADHD and ASD. We also identified 67 regions with genome-wide significant signals, amongst many others harboring SORCS3, NEGR1, and the hostgene of miR-9 as shared risk factors for ADHD and MDD. In addition, we are currently using, and will present results from, re-sampling procedures to study genetic correlation and individual SNP associations for individuals with ADHD and without comorbid ASD and/or MDD (and other phenotypes such as bipolar disorder, intellectual disability, and schizophrenia). We hope that these analyses together with other secondary analyses (e.g. using Mendelian Randomization) will help to identify genetically and phenotypically more homogenous subgroups of our sample in order to gain new insights in the etiology of ADHD and most importantly identify new strategies for prevention and treatment.

Toxoplasma gondii Exposure and the Risk of Attention Deficit Hyperactivity Disorder in Children and Adolescents.

Evidence suggests that Toxoplasma gondii, which causes toxoplasmosis, changes the metabolism of neurotransmitters, especially dopamine, resulting in both neurologic and psychiatric disorders. On the other hand, the dysregulation of catecholamines, especially of both norepinephrine and dopamine, has been proposed in the pathophysiology of attention deficit hyperactivity disorder (ADHD). The aim of the present study was to investigate anti-toxoplasma antibodies in children and adolescents with ADHD and compare it with a control group, to determine whether toxoplasmosis is a risk factor for ADHD. A total of 200 children and adolescents (117 patients with ADHD and 83 individuals without ADHD) participated in the study. Participants were tested for the presence of anti-T. gondii antibodies by enzyme-linked immunosorbent assay. A Parent ADHD Rating Scale and Clinical Global Impression-severity Scale were also completed. Data were analyzed using a χ test and Fisher exact test. Anti-toxoplasma antibodies were detected in 18.1% of patients with ADHD disorder and 24% of individuals without ADHD. There was no significant difference in seropositivity between the 2 groups (P > 0.05). The number of patients with T. gondii infection in the 3 subgroups was 0, 9 and 12, respectively. The differences in infection rate among subgroups were not statistically significant (P > 0.05). Although not conclusive, the present study does not support the theory that T. gondii is a risk factor for ADHD.

Functional analysis of a triplet deletion in the gene encoding the sodium glucose transporter 3, a potential risk factor for ADHD.

Sodium-glucose transporters (SGLT) belong to the solute carrier 5 family, which is characterized by sodium dependent transport of sugars and other solutes. In contrast, the human SGLT3 (hSGLT3) isoform, encoded by SLC5A4, acts as a glucose sensor that does not transport sugar but induces membrane depolarization by Na+ currents upon ligand binding. Whole-exome sequencing (WES) of several extended pedigrees with high density of attention-deficit/hyperactivity disorder (ADHD) identified a triplet ATG deletion in SLC5A4 leading to a single amino acid loss (ΔM500) in the hSGLT3 protein imperfectly co-segregating with the clinical phenotype of ADHD. Since mutations in homologous domains of hSGLT1 and hSGLT2 were found to affect intestinal and renal function, respectively, we analyzed the functional properties of hSGLT3[wt] and [ΔM500] by voltage clamp and current clamp recordings from cRNA-injected Xenopus laevis oocytes.The cation conductance of hSGLT3[wt] was activated by application of glucose or the specific agonist 1-desoxynojirimycin (DNJ) as revealed by inward currents in the voltage clamp configuration and cell depolarization in the current clamp mode. Almost no currents and changes in membrane potential were observed when glucose or DNJ were applied to hSGLT3[ΔM500]-injected oocytes, demonstrating a loss of function by this amino acid deletion in hSGLT3. To monitor membrane targeting of wt and mutant hSGLT3, fusion constructs with YFP were generated, heterologously expressed in Xenopus laevis oocytes and analyzed for membrane fluorescence by confocal microscopy. In comparison to hSGLT3[wt] the fluorescent signal of mutant [ΔM500] was reduced by 43% indicating that the mutant phenotype might mainly result from inaccurate membrane targeting. As revealed by homology modeling, residue M500 is located in TM11 suggesting that in addition to the core structure (TM1-TM10) of the transporter, the surrounding TMs are equally crucial for transport/sensor function.In conclusion, our findings indicate that the deletion [ΔM500] in hSGLT3 inhibits membrane targeting and thus largely disrupts glucose-induced sodium conductance, which may, in interaction with other ADHD risk-related gene variants, influence the risk for ADHD in deletion carriers.

Maternal infection requiring hospitalization during pregnancy and attention-deficit hyperactivity disorder in offspring: a quasi-experimental family-based study.

Maternal infection during pregnancy (IDP) has been associated with increased risk of attention-deficit/hyperactivity disorder (ADHD) in offspring. However, infection is associated with social adversity, poor living conditions and other background familial factors. As such, there is a need to rule out whether the observed association between maternal IDP and ADHD might be attributed to such confounding. This nationwide population-based cohort study using a family-based, quasi-experimental design included 1,066,956 individuals born in Sweden between 1992 and 2002. Data on maternal IDP (bacterial or viral) requiring hospitalization and ADHD diagnosis in offspring were gathered from Swedish National Registers, with individuals followed up through the end of 2009. Ordinary and stratified Cox regression models were used for estimation of hazard ratios (HRs) and several measured covariates were considered. Cousin- and sibling-comparisons accounted for unmeasured genetic and environmental factors shared by cousins and siblings. In the entire population, maternal IDP was associated with ADHD in offspring (HR=2.31, 95% CI=2.04-2.61). This association was attenuated when accounting for measured covariates (HR=1.86, 95% CI=1.65-2.10). The association was further attenuated when adjusting for unmeasured factors shared between cousins (HR=1.52, 95% CI=1.12-2.07). Finally, the association was fully attenuated in sibling comparisons (HR=1.03, 95% CI=0.76-1.41). This study suggests that the association between maternal IDP and offspring ADHD is largely due to unmeasured familial confounding. Our results underscore the importance of adjusting for unobserved familial risk factors when exploring risk factors for ADHD.

Oxidative stress contribution to attention deficit hyperactivity disorder in children with epilepsy

Children with epilepsy have a high incidence of attention deficit hyperactivity disorder (ADHD). Oxidation stress and disturbed neurotransmitters are suggested mechanisms; however, their role is not fully explored. This study evaluates the association between circulating malondialdehyde as an oxidation stress marker, apelin neuropeptide, and ADHD in children with epilepsy. Fifty children with epilepsy of unknown etiology, of which 25 have ADHD, as well as 35 healthy children were included. Serum levels of malondialdehyde and apelin were estimated. We investigated the association between seizure severity, response to medications, malondialdehyde, apelin levels, and ADHD in children with epilepsy. Serum malondialdehyde and apelin levels were higher in children with epilepsy, especially those with ADHD. Malondialdehyde and apelin levels have significant positive correlation with the Chalfont Seizure Severity Score. Regression analysis showed that elevated malondialdehyde is an independent risk factor for ADHD in children with epilepsy (OR: 1.401, 95%CI: 1.056–1.859, p= 0.02). No significant association was found between malondialdehyde and apelin levels and the type of epilepsy or ADHD. Longer duration of epilepsy, increased seizure severity, and uncontrolled seizures are associated with increased oxidation stress, which further increased susceptibility for ADHD. In spite of elevated apelin in children with ADHD, the elevation did not increase the risk of ADHD in children with epilepsy.

ADHD symptoms and body composition changes in childhood: a longitudinal study evaluating directionality of associations.

Attention-deficit/hyperactivity disorder (ADHD) is linked to increased risk of overweight/obesity among children and adults. Studies have also implicated obesity as a risk factor for ADHD. However, no studies have evaluated bidirectional, longitudinal associations between childhood fat mass and ADHD symptom severity. We investigate bidirectional associations between ADHD symptoms and measures of body composition between ages 1.5 and 9. We further examine effects of specific eating patterns linked to ADHD on associations between symptom severity and body composition. The study utilized data from children (N=3903) participating in the Generation R cohort (Netherlands). Children were enrolled at birth and retained regardless of ADHD symptoms over time. Cross-lagged and change models examined bidirectional associations between body composition (body mass index/dual-energy X-ray absorptiometry) and ADHD symptoms at four time points in childhood. A child with a clinically concerning ADHD symptom z-score two standard deviations above the mean at age 6 would be expected to experience about 0.22kg greater fat mass gain measured via dual-energy x-ray absorptiometry between ages 6 and 9, even if they displayed healthy eating patterns (95% CI: 0.11 - 0.28, p<0.001). Conversely, fat mass at any age did not predict worse ADHD symptoms later. Beginning in early childhood, more ADHD symptoms predict higher fat mass at later ages. We did not find evidence of a reverse association. Based on these and prior findings, lifestyle counselling during treatment for children with a diagnosis of ADHD should be considered, even if they are diagnosed in early childhood and do not yet have a body mass index of clinical concern.

Disturbed sleep and activity in toddlers with early signs of attention deficit hyperactivity disorder (ADHD).

This study investigated whether early signs of attention deficit hyperactivity disorder (ADHD) in toddlers aged 2-3years are associated with disturbed sleep and activity levels. Participants were recruited from the Odense Child Cohort, and children scoring above the 93rd percentile on the ADHD scale of the Child Behaviour Checklist 1½-5 were categorised as cases and compared with age- and gender-matched normal-scoring controls. Daytime and nocturnal activity for 24 children with ADHD traits (cases) and 25 healthy controls was assessed through 7days of actigraphy, and parents completed the Children's Sleep Habits Questionnaire (CSHQ) and the ADHD Rating Scale IV Preschool Version (ADHD-RS). Cases differed significantly on actigraphic parameters by having fewer minutes of moderate-to-vigorous physical activity (MVPA), prolonged total sleep time, fewer sleep interruptions, and increased night-to-night variability. A significant association was found between fewer minutes of MVPA and higher parent-reported motor activity on the ADHD-RS. Furthermore, increased night-to-night variability was significantly associated with higher total scores on both CSHQ and ADHD-RS. The findings show that early signs of ADHD are associated with an irregular sleep pattern and lower daytime activity, as illustrated by actigraphy. Studies investigating early ADHD risk factors could lead to a preschool ADHD risk index to help guide future early intervention.

Attention-deficit/hyperactivity disorder (ADHD) in adult psychiatry: Data on 12-month prevalence, risk factors and comorbidity

To examine the 12-month prevalence, risk factors, and comorbidity of ADHD in a collective of adult psychiatric patients admitted to an open general ward in a psychiatric hospital in Schleswig-Holstein (Germany) over a period of one year (n = 166). The 12-month prevalence of ADHD was 59.0 % (severe symptomatology: 33.1 %), high rates of comorbid disorders (92.9 % depression, 5.1 % bipolar disorder, 28.6 % anxiety disorder, 30.6 % emotional unstable (Borderline) personality disorder, 31.6 % avoidant personality disorder, 18.4 % dependent personality disorder, 25.5 % combined personality disorder, 10.2 % obsessive-compulsive personality disorder, 26.5 % PTSD, 25.5 % restless legs syndrome, 24.5 % adiposity, 11.2 % eating disorder, 45.9 % learning difficulty, 51.0 % nicotine dependency, 4.1 % alcohol dependency, 7.1 % illegal substance dependency), risk factors for ADHD, a high genetic risk (72.4 %) and problems in psychosocial functioning. Because of the high prevalence of ADHD in hospitalized psychiatric patients, it is mandatory to examine these for the presence of ADHD using questionnaires and identify comorbid diseases.

Prevalence of obesity/hypertension in children and adolescents with ADHD and evaluation of total body composition

Objective: Attention-deficithyperactivitydisorder (ADHD) is one of the most commonly diagnosed neurobehavioral disorders in childhood. The aim of the present study was to investigate the obesity/hypertension prevalence of chil-dren with ADHD at the time of initialdiagnosis, to assessthe total body composition, and also to evaluate the asso-ciated risk factors. Methods: The study was carried out with 77 ADHD/100 healthy children and adolescent. All individuals completed a questionnaire form prepared by researchers. The weight, height, and blood pressure (BP) measurements were performed using standardized protocols. Total body composition analysis was performed by ‘bioelectrical impedance analysis’ method. Results: The obesity/hypertension prevalence in ADHD patients were 16.9%, 13.0%, respectively. The obesity prevalence was more frequent and diastolic BP values were higher in pa-tients than controls. Total body fat (%) was higher in both obese and non-obese patients. In females, sistolic BP and diastolic BP values were higher in ADHD group than control group. In girls sleep duration in weekend-days was shorter in patients. Paternal body mass index was higher in ADHD group. Consumption of chocolate/sugar/chicken/ fish and screen time>1 hour in a day were more common in ADHD patients. Conclusion: The high obesity/hyper-tension rates in our study emphasize that the assessment of weight/BP should be a part of the ADHD management. The ADHD patients may also have an increased risk of high total body fat even though individuals are not obese. Short sleep duration, consumption of a high amount of chocolate/sugar/chicken/fish, andscreen time>1 hour per day may be a risk factor for ADHD.

ADHD and Early Experience: Revisiting the Case of Low Birth Weight.

* Abbreviations: ADHD — : attention-deficit/hyperactivity disorder LBW — : low birth weight PM — : premature The improving survival rates of extremely low, very low, and low birth weight (LBW) and premature (PM) infants are good news. Scientifically, they raise complex questions about trends in the incidence of neurodevelopmental conditions,1 from severe injuries like cerebral palsy, now declining after earlier increases in incidence,2 to subtler yet also disabling and costly conditions like attention-deficit/hyperactivity disorder (ADHD), whose true incidence likewise may not have increased in the past 15 years.3 In the accompanying meta-analysis by Franz et al,4 the magnitude of the association of LBW/PM with ADHD is striking; at a risk increase of ∼300%, it is perhaps the strongest single risk factor for ADHD of any type (biological or environmental) now known. At this effect size, LBW/PM would characterize a substantial portion of ADHD cases. Researchers of ADHD populations who can clarify how many patients had LBW/PM, and who can include more in-depth characterization of ADHD than was possible in many of the studies included by Franz et al,4 will help to determine how well these findings generalize across different sampling approaches. LBW is multiply determined, but it also has modest heritability.5 The authors of studies of LBW have rarely if ever … Address correspondence to Joel T. Nigg, PhD, Department of Psychiatry, Doernbecher Children’s Hospital, Oregon Health & Science University, Portland, OR 97238. E-mail: niggj{at}ohsu.edu

Maternal Smoking and Attention-Deficit/Hyperactivity Disorder in Offspring: A Meta-analysis.

Attention-deficit/hyperactivity disorder (ADHD) is a common neurodevelopmental disorder in childhood. Exploring the risk factors for ADHD is helpful in preventing ADHD. To explore the association between maternal smoking during pregnancy and the occurrence of ADHD in offspring. PubMed, Embase, and Cochrane Library were searched from inception to May 2017 for studies. Cohort or case-control studies in which the association between maternal smoking and ADHD in offspring were investigated were eligible if they included odds ratios (ORs), hazard ratios, or risk ratios and 95% confidence intervals (CIs). Two investigators independently extracted data on definition of exposure and outcome, number of cases and total sample population, and potential confounders adjusted. Any dose-relationship data for smoking and ADHD risk were also extracted. Fifteen cohort studies and 5 case-control studies with 50 044 cases and 2 998 059 participants were included. Smoking during pregnancy increased the risk of offspring ADHD (OR: 1.60; 95% CI: 1.45-1.76). The risk of ADHD was greater for children whose mothers were heavy smokers (OR: 1.75; 95% CI: 1.51-2.02) than for those mothers were light smokers (OR: 1.54; 95% CI: 1.40-1.70). The limitations of our study included different assessment tools of ADHD and a lack of objective biological measures for maternal smoking. With our meta-analysis, we provide evidence for an association between maternal smoking and offspring ADHD but do not solve the causality issues concerning potential confounding by other risk factors. More high-quality studies are needed to establish whether the association with smoking is causal.

Increased attention-deficit/hyperactivity symptoms in atopic dermatitis are associated with history of antihistamine use.

Epidemiologic evidence indicates a relevant association between atopic dermatitis (AD) and attention-deficit/hyperactivity disorder (ADHD). Underlying mechanisms and ways to best identify subgroups of AD patients at risk for ADHD are poorly understood. To compare sociodemographic, clinical and psychosocial characteristics of children with AD, ADHD, comorbid AD/ADHD and age-matched healthy controls and to investigate aspects of AD related to ADHD symptoms. Applying a factorial design, we investigated 4 groups of children aged 6-12years: AD-only (ie, without ADHD), ADHD-only (ie, without AD), AD+ADHD and healthy controls (HC; ie, no AD/no ADHD). Using validated instruments, ADHD symptoms and other behavioural problems, quality of life, parenting stress and sleeping problems were compared between groups. In children with AD-only, clinical signs (objective SCORAD), symptoms (POEM, VAS pruritus, VAS sleeping problems) and previous treatment of AD were assessed to investigate disease patterns related to ADHD symptoms. Compared to HC (n=47), children with AD-only (n=42), ADHD-only (n=34) and comorbid AD+ADHD (n=31) had significantly increased behavioural problems and decreased quality of life. Children with AD-only had significantly higher levels of ADHD symptoms than HC. In children with AD-only, previous use of antihistamines was significantly associated with increased ADHD symptoms (OR 1.88; 95% CI 1.04-3.39). Current clinical signs and AD symptoms were unrelated to the level of ADHD symptoms. Even if the clinical diagnosis of ADHD is excluded, children with AD show increased levels of ADHD symptoms. Further investigations need to determine whether early antihistamine exposure is a major risk factor for ADHD or a surrogate for previous AD severity and/or associated sleeping problems.

Factors related to pediatric obstructive sleep apnea-hypopnea syndrome in children with attention deficit hyperactivity disorder in different age groups.

This study aimed to retrospectively investigate the factors related to pediatric obstructive sleep apnea–hypopnea syndrome (OSAHS) with attention deficit hyperactivity disorder (ADHD) in children younger than 6 years and those older than 6 years.A total of 437 children who were hospitalized due to OSAHS between January 2014 and December 2014 were retrospectively reviewed. The children were further divided into OSAHS group and OSAHS + ADHD group. The general characteristics, OSA-18 quality of life, intention-hyperactivity score, and polysomnographic parameters (apnea–hypopnea index and the lowest oxygen saturation) were collected and compared between groups.There were 298 boys and 139 girls with the male to female ratio of 2.14:1. ADHD was found in 146 children including 105 boys and 41 girls with the male to female ratio of 2.56:1. Of these children, 31.62% and 35.46% had concomitant ADHD in children aged 4 to 5 years and those aged 6 to 11 years, respectively. In children aged 4 to 5 years, the incidence of allergic rhinitis was significantly higher (P = .016) and the adenoid hypertrophy was more severe (P = .001) in those with concomitant ADHD. In children aged 6 to 11 years, the tonsil hypertrophy was more severe in those with concomitant ADHD (P = .019). In children with concomitant ADHD, OSA-18 score was higher than in those with OSAHS alone (P < .001). Higher frequency of respiratory events (P < .001) and more severe hypoxia (P < .001) were found in children with concomitant ADHD than in those with OSAHS alone.As high as 30% of OSAHS children have concomitant ADHD, and the incidence of ADHD in OSAHS children is increasing over age. Boys are more likely to develop OSAHS and incidence of ADHD in OSAHS boys is higher than in OSAHS girls. In addition, risk factors of ADHD also vary between age groups. The ADHD is related to the severity of allergic rhinitis and adenoid hypertrophy in children aged 4 to 5 years, and to the severity of tonsil hypertrophy in children aged 6 to 11 years. Hypoxia may be an important factor causing ADHD. OSAHS should be treated as early as possible to reduce the incidence of ADHD in children.

Attention-Deficit/Hyperactivity Disorder (ADHD): Interaction between socioeconomic status and parental history of ADHD determines prevalence.

Many studies have reported a higher prevalence of Attention-Deficit/Hyperactivity Disorder (ADHD) among disadvantaged populations, but few have considered how parental history of ADHD might modify that relationship. We evaluated whether the prevalence of ADHD varies by socioeconomic status (SES) and parental history of ADHD in a population-sample of elementary school children age 6-14years. We screened all children in grades 1-5 in 17 schools in one North Carolina (U.S.) county for ADHD using teacher rating scales and 1,160 parent interviews, including an ADHD structured interview (DISC). We combined parent and teacher ratings to determine DSM-IV ADHD status. Data analysis was restricted to 967 children with information about parental history of ADHD. SES was measured by family income and respondent education. We found an interaction between family income and parental history of ADHD diagnosis (p=.016). The SES gradient was stronger in families without a parental history and weaker among children with a parental history. Among children without a parental history of ADHD diagnosis, low income children had 6.2 times the odds of ADHD (95% CI 3.4-11.3) as high income children after adjusting for covariates. Among children with a parental history, all had over 10 times the odds of ADHD as high income children without a parental history but the SES gradient between high and low income children was less pronounced [odds ratio (OR)=1.4, 95% CI 0.6-3.5]. Socioeconomic status and parental history of ADHD are each strong risk factors for ADHD that interact to determine prevalence. More research is needed to dissect the components of SES that contribute to risk of ADHD. Future ADHD research should evaluate whether the strength of other environmental risk factors vary by parental history. Early identification and interventions for children with low SES or parental histories of ADHD should be explored.

Cumulative exposure to childhood adversity, and treated attention deficit/hyperactivity disorder: a cohort study of 543 650 adolescents and young adults in Sweden.

Though childhood adversity (CA) has been associated with the risk of attention deficit/hyperactivity disorder (ADHD), little is known about the effect of cumulative CAs and whether there are clusters of CAs that are more closely related with ADHD. We used a Swedish cohort of 543 650 individuals born 1987-1991. Register-based CAs included familial death, substantial parental substance abuse and psychiatric disorder, substantial parental criminality, parental separation, household public assistance recipiency, and residential instability. Individuals were followed from year 2006 when they were 15-19 years of age, for treated ADHD, defined as a registered ICD diagnosis and/or prescription of medications to treat ADHD. Logistic regression analysis was used to calculate odds ratios (OR) with 95% confidence intervals (CI). Latent Class Analyses (LCA) were used to identify clusters based on the different CAs. All CAs increased the odds of ADHD in late adolescence and early adulthood; ORs ranged from 1.6 (95% CI 1.5-1.8) for familial death to 2.7 (95% CI 2.6-2.9) for household public assistance. We found a dose-response relationship between cumulative CA and ADHD; individuals with 4+ CAs had a markedly increased risk for ADHD (OR 5.5, 95% CI 5.0-6.0). LCA analyses revealed six distinct classes of CA associated with ADHD, of which 'exposure to most adversities' entailed highest risk. CA is a strong risk factor for ADHD, particularly when accumulated. Early and efficient detection of CA is of importance for interventions targeted to improve long-term mental health outcomes among disadvantaged children.

Maternal body mass index before pregnancy as a risk factor for ADHD and autism in children.

The risk of attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorders (ASD) may be influenced by environmental factors such as maternal obesity before pregnancy. Previous studies investigating those associations have found divergent results. We aim to investigate in a large birth cohort this association further in children with ADHD, ASD and comorbid ADHD and ASD. Our study population consisted of 81,892 mother-child pairs participating in the Danish National Birth Cohort (DNBC). Information about pre-pregnancy weight and height was collected in week 16 of pregnancy; the analysis was divided into groups based on BMI. Children with a clinical diagnosis of ADHD and/or ASD were identified in the Danish health registries at an average age of 13.3years. Hazard ratios (HRs) were estimated using time-to-event analysis. Compared to normal weight mothers, the risk of having a child with ADHD was significantly increased if the mother was overweight (HR=1.28 [95% CI 1.15;1.48]), obese (HR=1.47 [95% CI 1.26;1.71]) or severely obese (HR=1.95 [95% CI 1.58;2.40]). The same pattern was seen for the combined ADHD and ASD group. Regarding ASD, an increased risk was observed in underweight (HR=1.30 [95% CI 1.01;1.69]) and obese (HR=1.39 [95% CI 1.11;1.75]) mothers. Subgroup analysis revealed that the association in the ADHD group could mostly be attributable to the hyperactive group. Maternal obesity before pregnancy is a risk factor for ADHD in children. Maternal obesity as well as underweight may also be associated with an increased risk for ASD.

Impact of allergic airway diseases on risk of attention deficit hyperactivity disorder in school-age children

Objective: To investigate the impact of allergic airway diseases on the risk of attention deficit hyperactivity disorder (ADHD) in school-age children. Method: Used stratified cluster sampling method, school-age children in first to sixth grade in primary schools in 9 randomly selected cities including Shanghai, Guangzhou, Xi'an, and Wuhan were enrolled in the study. Interview of parents with questionnaires, which included school-age individual and family social environment questionnaire (including history of diagnosed ADHD, allergic rhinitis, and bronchial asthma) and Children's Sleep Habits Questionnaire (CSHQ), were finished and collected during November to December in 2005.Diagnosed allergic rhinitis and asthma by specialist were independent variables and divided into following three categories as no allergic diseases (neither allergic rhinitis nor asthma), single allergic disease (allergic rhinitis or asthma), and combined allergic diseases (allergic rhinitis and asthma). Diagnosed ADHD as dependent variable, binary logistic regress model was used to analyze the risks of ADHD in school-age children. Result: Totally 23 791 questionnaires were handed out, while 22 018 were collected. The children had an average age of (8.8±1.8) years, within which 10 869 were male, and 11 021 were female. The risk ratios of ADHD were 2.197 (95%CI: 1.823-2.648) and 3.150 (95%CI: 2.082-4.760) in children with single allergic disease and combined allergic diseases separately. There was no significant difference after adjusting for the factor of sleep habits, as the risk ratios were 2.055 (95%CI: 1.683-2.508) and 3.140 (95%CI: 2.061-4.784) in children with single and combined allergic airway disease separately. Conclusion: Allergic rhinitis and bronchial asthma increased the risk of ADHD, not depending on sleep habits. Hence, allergic airway diseases could be independent risk factors of ADHD.