Impact of asthma medication and familial factors on the association between childhood asthma and attention-deficit/hyperactivity disorder: a combined twin- and register-based study: Epidemiology of Allergic Disease

Roles of Psychological Flexibility, Parenting Competence, and Asthma Management Self-Efficacy in the Functioning Outcomes of Parents of Children with Asthma Co-Occurring with Attention-Deficit/Hyperactivity Disorder

Asthma and ADHD represent prevalent pediatric conditions, with the former being a physical disorder and the latter being a neurodevelopmental disorder. This study examined the influence of parental psychological flexibility (PF)-the ability to adapt to evolving situational demands, shift perspectives, and balance competing priorities-alongside parenting competence and asthma management self-efficacy on family functioning and parental psychological adjustment in families with children exhibiting concurrent asthma and ADHD symptoms. Baseline data were analyzed from 130 parents (mean age = 40.3 years, SD = 5.5; 88.9% mothers) of children diagnosed with both asthma and ADHD (mean age = 8.0 years, SD = 2.2; 74.6% boys), who were participating in a randomized controlled trial evaluating an Acceptance and Commitment Therapy (ACT)-based parenting intervention. An adjusted structural equation model revealed that greater parental psychological inflexibility was significantly associated with poorer family functioning (β = -0.61, 95% CI [-0.74, -0.33], p < 0.001) and increased psychological maladjustment (β = 0.48, 95% CI [0.32, 0.63], p < 0.001), accounting for intercorrelations with parenting competence and parental asthma management self-efficacy. Additionally, parental psychological flexibility was found to mediate the relationship between parenting competence and both family functioning and psychological adjustment. These findings underscore the importance of targeting parental psychological inflexibility and enhancing parenting competence in interventions to improve family dynamics and parental mental health and thereby suggest a shift from the traditional focus on self-efficacy in symptom management for pediatric asthma and ADHD.

Rhinorrhea and watery eyes in infancy and risk of attention-deficit hyperactivity disorder in school-age children

Increased parasympathetic nervous system (PNS) activity is associated with attention-deficit/hyperactivity disorder (ADHD) inattentive symptoms, but not hyperactive-impulsive symptoms, and may contribute to inattentive subtype etiology. Guided by prior work linking infant rhinorrhea and watery eyes without a cold (RWWC) to PNS dysregulation, we examined associations between infant RWWC and childhood ADHD symptoms in a longitudinal cohort of Black and Latinx children living in the context of economic disadvantage (N = 301 youth: 158 females, 143 males). Infant RWWC predicted higher inattentive (relative risk [RR] 2.16, p < .001) but not hyperactive-impulsive (RR 1.53, p = .065) ADHD symptoms (DuPaul scale), administered to caregivers at child age 8-14 years. Stratified analyses revealed that these associations were present in females but not males, who were three times more likely to have higher ADHD current total symptoms if they had infant RWWC than if they did not. Additionally, associations between RWWC and inattention symptoms were observed only in females. RWWC may thus serve as a novel risk marker of ADHD inattentive-type symptoms, especially for females.

Omalizumab in combination with subcutaneous immunotherapy for the treatment of multiple allergies associated with attention-deficit/hyperactivity disorder: a case report and a literature review

We describe the case of a 10-year-old boy with asthma (AS), accompanied by allergic rhinitis (AR), food allergy (FA), and combined attention-deficit/hyperactivity disorder (ADHD), who was treated at Shanghai Renji Hospital on 11 July 2020. The efficiency of the previous treatment with salmeterol/ticlosone was poor. Treatment with montelukast sodium resulted in development of neurological symptoms. Treatment with omalizumab in combination with subcutaneous immunotherapy (SCIT) was then initiated in our department based on anti-asthmatic therapy. Symptoms of asthma were completely controlled, and FA and AR symptoms improved. The treatment regimen led to a significant improvement in ADHD symptoms and the overall quality of life of the patient. The literature search was done in the PubMed database using "attention deficit/hyperactivity disorder/ADHD" and "asthma" as keywords, and we identified 47 relevant articles. In conclusion, our results show that treating asthma with omalizumab in combination with salmeterol/ticlosone and SCIT is efficient in controlling symptoms of multiple allergies and may lead to the improvement in ADHD symptoms and the overall quality of life of pediatric patients with ADHD. While current studies suggest that allergic diseases are closely related to ADHD, there is still a lack of studies or case reports of complete treatment protocols to provide clinical clues for management of the disease.

Associations between symptoms of attention-deficit hyperactivity disorder, socioeconomic status and asthma in children

Socioeconomic status (SES) influences the risk of both physical diseases, such as asthma, and neurodevelopmental conditions, including attention-deficit/hyperactivity disorder (ADHD). Using Causal Mediation Analysis on French birth-cohort data, we found a causal pathway from SES to ADHD symptoms, in part mediated by asthma. An increase in family income at age 3 by one unit resulted in lower ADHD symptoms at age 5, by -0.37 [95% CI: -0.50, -0.24] SDQ-score-points, with additional -0.04 [95% CI: -0.08, -0.01] points reduction indirectly via asthma at age 3, both with statistical significance. Importantly, family income at age 3 exerted both direct and indirect (via asthma) negative effects on later ADHD symptoms with much higher magnitudes for the direct effect. Our findings underscore the importance of apprehending ADHD symptoms in the broader context of socioeconomic disparities, along with their comorbidities with asthma, potentially influencing public health interventions and clinical practice in managing ADHD.

The influence of asthma on neuroinflammation and neurodevelopment: From epidemiology to basic models

Asthma is a highly heterogeneous inflammatory disease that can have a significant effect on both the respiratory system and central nervous system. Population based studies and animal models have found asthma to be comorbid with a number of neurological conditions, including depression, anxiety, and neurodevelopmental disorders. In addition, maternal asthma during pregnancy has been associated with neurodevelopmental disorders in the offspring, such as autism spectrum disorders and attention deficit hyperactivity disorder. In this article, we review the most current epidemiological studies of asthma that identify links to neurological conditions, both as it relates to individuals that suffer from asthma and the impacts asthma during pregnancy may have on offspring neurodevelopment. We also discuss the relevant animal models investigating these links, address the gaps in knowledge, and explore the potential future directions in this field.

Attention-Deficit Hyperactivity Disorder Symptoms, Underperception of Respiratory Compromise, and Illness Representations in Black and Latino Children With Asthma

OBJECTIVE

This study examined the associations between attention-deficit/hyperactivity disorder (ADHD) symptoms, underperception of respiratory compromise, and illness representations in Black and Latino children with asthma. We hypothesized that increased child-reported ADHD symptoms, as well as parent reports for their child, would be associated with underperception of respiratory compromise, and maladaptive asthma beliefs.

METHODS

Two hundred ninety-six parent-child dyads were recruited from pediatric asthma and primary care clinics in the Bronx. Participants completed demographic questionnaires, the Conners-3 ADHD Index to measure ADHD symptoms, and the Asthma Illness Representation Scale to assess asthma beliefs. Perception of respiratory compromise was assessed by programmable electronic peak flow monitors that measured the child's subjective estimates of peak expiratory flow (PEF) and actual PEF, with underperception as the primary measure.

RESULTS

Child-reported ADHD symptoms were associated with greater underperception (β = .117, p = .049) of respiratory compromise. Parent-reported ADHD symptoms were associated with greater underperception (β = .129, p = .028) of respiratory compromise. Child-reported ADHD symptoms (β = -.188, p < .001) were associated with more maladaptive asthma beliefs, F(1, 341) = 13.135. Parent-reported ADHD symptoms (β = -.203, p ≤ .001) were associated with more maladaptive asthma beliefs, F(1, 341) = 15.644.

CONCLUSIONS

ADHD symptoms were associated with a greater underperception of respiratory compromise and more maladaptive asthma beliefs. Deficits of attentional processes and/or hyperactivity levels might be contributing factors. We emphasize the need for psychoeducation and interventions that improve perception and health beliefs in children with comorbid ADHD and asthma.

Is Histamine and Not Acetylcholine the Missing Link between ADHD and Allergies? Speer Allergic Tension Fatigue Syndrome Re-Visited

Speer allergic tension-fatigue syndrome (SATFS) is a classic allergy syndrome characterized by allergy-like symptoms, muscle tension, headaches, chronic fatigue, and other particular behaviors that were initially described in the fifties. The particular behaviors displayed include symptoms such as hyperkinesis, hyperesthesia (i.e., insomnia), restlessness, and distractibility, among others. Interestingly, these symptoms are very similar to descriptions of attention deficit hyperactivity disorder (ADHD), the most prevalent neurodevelopmental disorder worldwide, which is characterized by inattention, hyperactivity, and impulsivity. The clinical description of SATFS precedes the nomination of ADHD in 1960 by Stella Chess. In this conceptual paper, we stress that there is a gap in the research on the relationship between ADHD and allergic pathologies. The hypotheses of this conceptual paper are (1) SATFS is probably one of the first and best historical descriptions of ADHD alongside a common comorbidity (allergy) displayed by these patients; (2) SATFS (ADHD) is a systemic disease that includes both somatic and behavioral manifestations that may influence each other in a bidirectional manner; (3) The role of neuroinflammation and histamine is key for understanding the pathophysiology of ADHD and its frequent somatic comorbidities; (4) The deficiency of the diamine oxidase (DAO) enzyme, which metabolizes histamine extracellularly, may play a role in the pathophysiology of ADHD. Decreased DAO activity may lead to an accumulation of histamine, which could contribute to core ADHD symptoms and comorbid disorders. Further empirical studies are needed to confirm our hypotheses.

Evaluation of the frequency of attention deficit hyperactivity disorder in patients with asthma

BACKGROUND

Asthma is the most prevalent respiratory disease caused by chronic airway inflammation. Attention Deficit Hyperactivity Disorder (ADHD) is children's most common psychological and neurodevelopmental disorder. Increased risk for ADHD in patients with inflammatory and autoimmune diseases supports the role of inflammatory mechanisms in the occurrence of ADHD. However, the association between asthma and ADHD remains unclear.

OBJECTIVE

This study was designed to evaluate the prevalence of ADHD in patients with asthma who were referred to the clinic of allergy and clinical immunology.

METHODS

This cross-sectional study was conducted on children aged 6 to 18 with asthma at Imam Ali hospital, Karaj, Iran. The patient's demographic data, history of childbirth delivery type, premature birth, hospital admission, family income, birth rate, and family history information related to the patient's asthma and medicines were recorded. ADHD diagnosis was made using the Persian version of Conners Parent Behavioral Problems Rating Scale (CPRS-26).

RESULTS

In this study, 677 asthmatic patients were enrolled; 46 patients (6.8%) had ADHD. The probability of ADHD in asthmatic patients inhabited in a rural area, males, and patients with a history of food allergy, allergic rhinitis, urticaria, and eczema was significantly higher (p < 0.05). In addition, our result demonstrated that the likelihood of ADHD in patients with asthma and a history of PICU admission was significantly higher (p < 0.05).

CONCLUSIONS

The present study showed that severe asthma, was the risk factor for ADHD in patients with asthma. Physicians should be aware of this co-morbidity to refer asthmatic patients who have the symptoms of ADHD to a psychologist.

Genetic and environmental contributions to co-occurring physical health conditions in autism spectrum condition and attention-deficit/hyperactivity disorder

BACKGROUND

Autism spectrum condition and attention-deficit/hyperactivity disorder (ADHD) are associated with a range of physical health conditions. The aim of this study was to examine the etiological components contributing to co-occurring physical health conditions in autism and ADHD.

METHODS

In this nationwide Child and Adolescent Twin Study in Sweden, we analyzed data from 10,347 twin pairs aged 9 and 12. Clinical diagnoses of autism, ADHD, and physical health conditions were identified through the Swedish National Patient Register. Subclinical phenotypes of autism and ADHD were defined by symptom thresholds on a standardized parent-interview, the Autism-Tics, ADHD, and Other Comorbidities inventory. Associations between physical health conditions and autism/ADHD phenotypes were examined using generalized estimating equations. Bivariate twin models were applied to estimate the extent to which genetic and environmental risk factors accounted for physical health comorbidities.

RESULTS

Similar patterns of association with physical health conditions were found in clinical and subclinical autism/ADHD, with odds ratios ranging from 1.31 for asthma in subclinical ADHD to 8.03 for epilepsy in clinical autism. The estimated genetic correlation (r_a) with epilepsy was 0.50 for clinical autism and 0.35 for subclinical autism. In addition, a modest genetic correlation was estimated between clinical autism and constipation (r_a = 0.31), functional diarrhea (r_a = 0.27) as well as mixed gastrointestinal disorders (r_a = 0.30). Genetic effects contributed 0.86 for mixed gastrointestinal disorders in clinical ADHD (r_a = 0.21). Finally, subclinical ADHD shared genetic risk factors with epilepsy, constipation, and mixed gastrointestinal disorders (r_a = 0.30, 0.17, and 0.17, respectively).

LIMITATIONS

Importantly, since medical records from primary care were not included in the registry data used, we probably identified only more severe rather than the full range of physical health conditions. Furthermore, it needs to be considered that the higher prevalence of physical health conditions among autistic children and children with ADHD could be associated with the increased number of medical visits.

CONCLUSIONS

Shared genetic effects contribute significantly to autism and ADHD phenotypes with the co-occurring physical health conditions across different organ systems, including epilepsy and gastrointestinal disorders. The shared genetic liability with co-occurring physical health conditions was present across different levels of autism and ADHD symptom severity.

Association of corticosteroid use and attention deficit/hyperactivity disorder in asthmatic children varies by age

OBJECTIVE

We aim to examine the impact of corticosteroids use on ADHD among children with asthma by administration routes.

METHODS

A population-based, cross-sectional analysis included pediatric patients ages 5-20 years old from the 2016 and 2019 Kids Inpatient Database (unweighted N = 111,702). ICD-10-CM codes were used to identify corticosteroids use, asthma, and ADHD cases. Survey logistic regression models with purposeful variable selection algorithms were built to examine the association between corticosteroids use, and ADHD by asthma severity and age. An inverse probability weighting (IPW) approach was used to help further control residual confounding.

RESULTS

Among children aged 5-11 years old, the odds of ADHD were significantly higher in children with moderate to severe asthma who used inhaled corticosteroids than nonusers (moderate asthma: adjusted odds ratios [aOR] 1.46, 95% confidence interval [CI] 1.14-2.44; severe asthma: aOR 1.61, 95% CI 1.18-2.21). Although oral corticosteroid use was not independently associated with ADHD in young children, combined use of inhaled and oral corticosteroid had almost 5 times higher odds of use among ADHD in children with severe asthma vs. nonusers (aOR 4.85, 95% CI 2.07 - 11.35). No associations were found between any corticosteroid use and ADHD among asthmatic children aged 12-20 years.

CONCLUSIONS

In this retrospective analysis, we found inhaled corticosteroids were positively associated with ADHD in younger children with moderate to severe asthma, but not in older children.

Paediatric asthma and non-allergic comorbidities: A review of current risk and proposed mechanisms

It is increasingly recognized that children with asthma are at a higher risk of other non-allergic concurrent diseases than the non-asthma population. A plethora of recent research has reported on these comorbidities and progress has been made in understanding the mechanisms for comorbidity. The goal of this review was to assess the most recent evidence (2016-2021) on the extent of common comorbidities (obesity, depression and anxiety, neurodevelopmental disorders, sleep disorders and autoimmune diseases) and the latest mechanistic research, highlighting knowledge gaps requiring further investigation. We found that the majority of recent studies from around the world demonstrate that children with asthma are at an increased risk of having at least one of the studied comorbidities. A range of potential mechanisms were identified including common early life risk factors, common genetic factors, causal relationships, asthma medication and embryologic origins. Studies varied in their selection of population, asthma definition and outcome definitions. Next, steps in future studies should include using objective measures of asthma, such as lung function and immunological data, as well as investigating asthma phenotypes and endotypes. Larger complex genetic analyses are needed, including genome-wide association studies, gene expression-functional as well as pathway analyses or Mendelian randomization techniques; and identification of gene-environment interactions, such as epi-genetic studies or twin analyses, including omics and early life exposure data. Importantly, research should have relevance to clinical and public health translation including clinical practice, asthma management guidelines and intervention studies aimed at reducing comorbidities.

Genetics of Attention-Deficit Hyperactivity Disorder

Attention-Deficit Hyperactivity Disorder (ADHD) has long been recognized as being a highly heritable condition and our understanding of the genetic contributions to ADHD has grown over the past few decades. This chapter will discuss the studies that have examined its heritability and the efforts to identify specific genetic risk-variants at the molecular genetic level. We outline the various techniques that have been used to characterize genetic contributions to ADHD, describing what we have learnt so far, what there is still to learn and the methodologies that can be used to further our knowledge. In doing so we will discuss research into rare and common genetic variants, polygenic risk scores, and gene-environment interplay, while also describing what genetic studies have revealed about the biological processes involved in ADHD and what they have taught us about the overlap between ADHD and other psychiatric and somatic disorders. Finally, we will discuss the strengths and limitations of the current methodologies and clinical implications of genetic research to date.

Associations Between Pregnancy-Related Predisposing Factors for Offspring Neurodevelopmental Conditions and Parental Genetic Liability to Attention-Deficit/Hyperactivity Disorder, Autism, and Schizophrenia: The Norwegian Mother, Father and Child Cohort Study (MoBa)

Importance

Several maternal exposures during pregnancy are considered predisposing factors for offspring neurodevelopmental conditions. However, many of these exposures may be noncausal and biased by maternal genetic liability.

Objective

To assess whether pregnancy-related predisposing factors for offspring neurodevelopmental conditions are associated with maternal genetic liability for attention-deficit/hyperactivity disorder (ADHD), autism, and schizophrenia and to compare associations for maternal genetic liability with those for paternal genetic liability, which could indicate that paternal exposures are not suitable negative controls for maternal exposures.

Design, Setting, and Participants

The Norwegian Mother, Father and Child Cohort Study (MoBa) is a population-based pregnancy cohort that recruited parents from June 1999 to December 2008. Polygenic scores (PGS) for ADHD, autism, and schizophrenia were derived in mothers and fathers. The associations between maternal PGS and 37 pregnancy-related measures were estimated, and these results were compared with those from paternal PGS predicting paternal measures during the mother's pregnancy. Analysis took place between March 2021 and March 2022.

Exposures

PGS for ADHD, autism, and schizophrenia, calculated (using discovery effect size estimates and threshold of P < .05) from the largest available genome-wide association studies.

Main Outcomes and Measures

Self-reported pregnancy-related measures capturing lifestyle behaviors, metabolism, infectious and autoimmune diseases, other physical health conditions, and medication use.

Results

Data were available for up to 14 539 mothers (mean [SD] age, 30.00 [4.45] years) and 14 897 fathers (mean [SD] age, 32.46 [5.13] years) of European ancestry. Modest but robust associations were observed between specific pregnancy-related measures and maternal PGS, including ADHD PGS with asthma (odds ratio [OR], 1.15 [95% CI, 1.06-1.25]), smoking (OR, 1.26 [95% CI, 1.19-1.33]), prepregnancy body mass index (β, 0.25 [95% CI, 0.18-0.31]), pregnancy weight gain (β, 0.20 [95% CI, 0.10-0.30]), taking folate (OR, 0.92 [95% CI, 0.88-0.96]), and not taking supplements (OR, 1.09 [95% CI, 1.04-1.14]). Schizophrenia PGS was associated with coffee consumption (OR, 1.09 [95% CI, 1.05-1.12]), smoking (OR, 1.12 [95% CI, 1.06-1.19]), prepregnancy body mass index (β, -0.18 [95% CI, -0.25 to -0.11]), and pregnancy weight gain (β, 0.17 [95% CI, 0.07-0.27]). All 3 PGSs associated with symptoms of depression/anxiety (ADHD: OR, 1.15 [95% CI, 1.09-1.22]; autism: OR, 1.13 [95% CI, 1.06-1.19]; schizophrenia: OR, 1.13 [95% CI, 1.07-1.20]). Associations were largely consistent for maternal and paternal PGS, except ADHD PGS and smoking (fathers: OR, 1.13 [95% CI, 1.09-1.17]).

Conclusions and Relevance

In this study, genetic liability to neurodevelopmental conditions that is passed from mothers to children was associated with several pregnancy-related factors and may therefore confound associations between these pregnancy-related factors and offspring neurodevelopment that have previously been thought to be causal. It is crucial that future study designs account for genetic confounding to obtain valid causal inferences so that accurate advice can be given to pregnant individuals.

Behavioural side effects of inhaled corticosteroids among children and adolescents with asthma

Background

Inhalation corticosteroids (ICS) are prescribed for treatment of asthma in approximately 3% of all children in Denmark. Despite limited evidence, case reports suggest that ICS-related behavioural adverse drug events (ADEs) may be frequent. In general, underreporting of ADEs to official databases is common, and little is known about doctor’s clinical experiences with behavioural ADEs when prescribing ICS for children with asthma. The objective was to investigate the extent of behavioural ADEs in children with asthma treated with ICS by comparing database findings to experiences of specialist doctors.

Methods

First, databases of the European Medicines Agency (EMA) and the Danish Medicines Agency (DKMA) were searched for reports made by healthcare professionals about behavioural ADEs in children from 2009 to 2018. Second, questionnaire data on behavioural ADEs were collected from eight of the 11 specialist doctors responsible for treating children with asthma at the six paediatric departments in Central Denmark Region and North Denmark Region.

Results

EMA and DKMA had registered 104 and 3 reports, respectively, on behavioural ADEs during the 10-year study period. In contrast, five of the eight specialist doctors (45.5%) had experienced patients who had developed behavioural changes during ICS treatment. However, none of the five specialist doctors had filed reports on these events to DKMA.

Conclusion

Behaviour-related ADEs to ICS in children with asthma are likely to be highly underreported in official databases and doctors treating children with ICS should be aware of potential ADEs and consider submitting ADE reports whenever appropriate.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-02112-8.

Association between Polygenic Risk Scores for ADHD and Asthma: A Birth Cohort Investigation

OBJECTIVE

Shared genetic mechanisms have been hypothesized to explain the comorbidity between ADHD and asthma. To evaluate their genetic overlap, we relied on data from the 1982 Pelotas birth cohort to test the association between polygenic risk scores (PRSs) for ADHD (ADHD-PRSs) and asthma, and PRSs for asthma (asthma-PRSs) and ADHD.

METHOD

We analyzed data collected at birth, 2, 22, and 30 years from 3,574 individuals.

RESULTS

Subjects with ADHD had increased risk of having asthma (OR 1.92, 95% CI 1.01-3.66). The association was stronger for females. Our results showed no evidence of association between ADHD-PRSs and asthma or asthma-PRSs and ADHD. However, an exploratory analysis suggested that adult ADHD might be genetically associated with asthma.

CONCLUSION

Our results do not support a shared genetic background between both conditions. Findings should be viewed in light of important limitations, particularly the sample size and the self-reported asthma diagnosis. Studies in larger datasets are required to better explore the genetic overlap between adult ADHD and asthma.

Familial liability to asthma and ADHD: A Swedish national register-based study

Background

Studies have reported significant associations between asthma and attention-deficit/hyperactivity disorder (ADHD), but whether the association is due to shared etiology such as shared genetic risk factors remains unclear. We aimed to investigate patterns of familial co-aggregation of asthma and ADHD and also to quantify the relative contribution of genetic and environmental influences.

Methods

Through Swedish register linkages, we obtained a cohort of 927,956 individuals born 1992-2001 and identified monozygotic twins (MZ), dizygotic twins (DZ), full- and half-siblings, and full- and half-cousins. Clinical diagnosis of asthma and ADHD were identified from the Swedish national registers. We used logistic regressions to investigate the within-individual association and familial co-aggregation between asthma and ADHD. We then used bivariate twin modeling to quantify the genetic and environmental correlations and their contributions to the familial liability.

Results

Individuals with asthma had significantly higher risk of ADHD (odds ratio [OR], 1.50; 95% confidence interval [CI], 1.47-1.54). Relatives of individuals with asthma had an increased risk of ADHD compared to relatives of individuals without asthma; in familial co-aggregation analysis, the association was strongest in MZ twins (OR, 1.67; 95% CI, 0.99-2.84) and attenuated with degree of genetic relatedness. In the twin modeling, the phenotypic and genetic correlations between asthma and ADHD estimated from the ACE model were 0.09 (95% CI, 0.05-0.14) and 0.12 (95% CI, 0.02-0.21), respectively. The bivariate heritability was 0.88 (95% CI, 0.30-1.46). Estimates for contributions from shared and non-shared environment factors were not statistically significant.

Conclusions

Asthma and ADHD co-aggregate in families primarily due to shared genetic risk factors. Within-individual and family history of either disorder should prompt clinical assessment of the other condition. Future studies should further investigate genetic variants underlying the co-occurrence of ADHD and asthma.

Non-mental diseases associated with ADHD across the lifespan: Fidgety Philipp and Pippi Longstocking at risk of multimorbidity?

Several non-mental diseases seem to be associated with an increased risk of ADHD and ADHD seems to be associated with increased risk for non-mental diseases. The underlying trajectories leading to such brain-body co-occurrences are often unclear - are there direct causal relationships from one disorder to the other, or does the sharing of genetic and/or environmental risk factors lead to their occurring together more frequently or both? Our goal with this narrative review was to provide a conceptual synthesis of the associations between ADHD and non-mental disease across the lifespan. We discuss potential shared pathologic mechanisms, genetic background and treatments in co-occurring diseases. For those co-occurrences for which published studies with sufficient sample sizes exist, meta-analyses have been published by others and we discuss those in detail. We conclude that non-mental diseases are common in ADHD and vice versa and add to the disease burden of the patient across the lifespan. Insufficient attention to such co-occurring conditions may result in missed diagnoses and suboptimal treatment in the affected individuals.

Insights into attention-deficit/hyperactivity disorder from recent genetic studies

Attention-deficit/hyperactivity disorder (ADHD) is a common and highly heritable neurodevelopmental disorder (NDD). In this narrative review, we summarize recent advances in quantitative and molecular genetic research from the past 5-10 years. Combined with large-scale international collaboration, these advances have resulted in fast-paced progress in understanding the etiology of ADHD and how genetic risk factors map on to clinical heterogeneity. Studies are converging on a number of key insights. First, ADHD is a highly polygenic NDD with a complex genetic architecture encompassing risk variants across the spectrum of allelic frequencies, which are implicated in neurobiological processes. Second, genetic studies strongly suggest that ADHD diagnosis shares a large proportion of genetic risks with continuously distributed traits of ADHD in the population, with shared genetic risks also seen across development and sex. Third, ADHD genetic risks are shared with those implicated in many other neurodevelopmental, psychiatric and somatic phenotypes. As sample sizes and the diversity of genetic studies continue to increase through international collaborative efforts, we anticipate further success with gene discovery, characterization of how the ADHD phenotype relates to other human traits and growing potential to use genomic risk factors for understanding clinical trajectories and for precision medicine approaches.

Attention-deficit/hyperactivity disorder has a state-dependent association with asthma: The role of systemic inflammation in a population-based birth cohort followed from childhood to adulthood

There is a high comorbidity between attention-deficit/hyperactivity disorder (ADHD) and asthma, and inflammation has been proposed as a potential pathophysiological mechanism behind this association. Most studies conducted so far have used a cross-sectional design, and none has evaluated the prevalence of asthma symptoms in patients with ADHD followed from childhood to adulthood. We relied on data from the 1993 Pelotas birth cohort to evaluate the association between ADHD and asthma in patients with distinct patterns of incidence, persistence and remission, and to explore the potential role of inflammatory markers in the comorbidity. We analyzed data from 3281 individuals from the 1993 Pelotas birth cohort collected at birth (1993), 11 years (2004), 18 years (2011), and 22 years (2015). Subjects were first classified according to their ADHD and asthma status as early-onset (EO) persistent (positive screening for ADHD at 11 years and diagnosis of ADHD according to DSM-5, except criterion E, at either 18 or 22 years), EO-remittent (positive screening for ADHD at 11 years only), late-onset (diagnosis of ADHD according to DSM-5, except criterion E, at 18 or 22 years only), or healthy subjects (negative for both conditions in all evaluation). After controlling for confounders, significant associations were observed between EO-remittent ADHD and EO-remittent asthma (OR 1.68, 95% CI 1.11-2.55), EO-persistent ADHD and EO-persistent asthma (OR 4.33, 95% CI 1.65-11.34), and between late-onset ADHD and late-onset asthma (OR 1.86, 95% CI 1.28-2.70), suggesting a state-dependent association. Serum interleukin-6 (IL-6) and C-reactive protein (CRP) were measured at the 18- and 22-year evaluations and compared between subjects positive for ADHD, asthma, and subjects with both or none conditions, regardless of the previously defined trajectories. Subjects with comorbid ADHD and asthma presented higher levels of IL-6 at the 18- and 22-year evaluations when compared to subjects negative for both conditions. Our results demonstrate a state-dependent association between ADHD and asthma despite underlying trajectories. Higher levels of serum IL-6 in patients with both conditions suggest that a pro-inflammatory environment might have a role in the pathophysiological mechanisms underlying the comorbidity.

Technological readiness and implementation of genomic-driven precision medicine for complex diseases

The fields of human genetics and genomics have generated considerable knowledge about the mechanistic basis of many diseases. Genomic approaches to diagnosis, prognostication, prevention and treatment - genomic-driven precision medicine (GDPM) - may help optimize medical practice. Here, we provide a comprehensive review of GDPM of complex diseases across major medical specialties. We focus on technological readiness: how rapidly a test can be implemented into health care. Although these areas of medicine are diverse, key similarities exist across almost all areas. Many medical areas have, within their standards of care, at least one GDPM test for a genetic variant of strong effect that aids the identification/diagnosis of a more homogeneous subset within a larger disease group or identifies a subset with different therapeutic requirements. However, for almost all complex diseases, the majority of patients do not carry established single-gene mutations with large effects. Thus, research is underway that seeks to determine the polygenic basis of many complex diseases. Nevertheless, most complex diseases are caused by the interplay of genetic, behavioural and environmental risk factors, which will likely necessitate models for prediction and diagnosis that incorporate genetic and non-genetic data.

Family and developmental history of ADHD patients: a structured clinical routine interview identifies a significant profile

Similar to other neurodevelopmental disorders, the diagnosis of attention-deficit hyperactivity disorder (ADHD) is based on clinical and psychosocial assessment. This assessment is performed in clinical practice using the clinical routine interview technique. Domains of the clinical routine interview are, among others, present symptoms, history of present illness and family and developmental history. Family and developmental history are important parts in the diagnostic process of ADHD. In contrast to the domains of present symptoms and history of present illness, there are currently no structured interviews or rating scales available to thoroughly assess family and developmental history in ADHD. The aim of the study was to assess the profile of operationalized data from a structured clinical routine interview addressing family and developmental history from ADHD patients and control participants. A structured interview to assess family and developmental history was derived from the guidelines used at different university hospitals for Child and Adolescent Psychiatry as well as from the descriptions in leading textbooks. Based on these guidelines and descriptions, the interview was an optimization of possible questions. Clinical data were obtained from parents of male patients who had the diagnosis of ADHD between the ages of 12-17 years (n = 44), and of healthy controls (n = 41). Non-metric data were operationalized into three categories, 0-normal behavior, 1-minor pathological behavior, 2-major pathological behavior. ADHD patients express a profile that significantly differs from control participants. Comparison of significant items with the empirical ADHD literature indicates strong agreement. Our findings support the importance and feasibility of the clinical routine interview in family and developmental history in the context of diagnosing ADHD.

Montelukast does not increase the risk of attention-deficit/hyperactivity disorder in pediatric asthma patients: A nationwide population-based matched cohort study

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) has been linked to pediatric asthma patients treated with montelukast. This study is the first to use a nationwide health insurance research database (NHIRD) to study whether asthmatic children using montelukast are at an increased risk of ADHD.

METHODS

We used data from the Taiwan NHIRD, which is a longitudinal database of one million randomly selected subjects. The enrolled patients were followed up until 2013. Patients younger than and equal to 12 years old with new-onset asthma (ICD-9 CM code 493.X) diagnosed between 1997 and 2013 were enrolled. A multivariate Cox regression analysis was conducted to evaluate the association between montelukast treatment and the risk of ADHD (ICD-9-CM code 314.X).

RESULTS

We enrolled a total of 54,487 asthmatic children younger than and equal to 12 years old who had at least one claim of inpatient admission or at least three claims of an ambulatory visit. Montelukast users and match controls were identified by matching age, gender, residence, the comorbidities including allergic rhinitis and atopic dermatitis, admission or emergency department visits due to asthma attack, and index date of starting montelukast in a 1:1 ratio, with 12,806 in the montelukast group and 12,806 in the non-montelukast group. The montelukast group had a similar risk of ADHD (n = 632, 4.94%) as the non-montelukast group (n = 610, 4.76%) [adjusted hazard ratio 1.04; 95% confidence interval, 0.93 to 1.17]. In children treated with montelukast, high cumulative days of montelukast use did not increase the risk of ADHD.

CONCLUSION

This nationwide population-based cohort study reveals that asthma children treated with montelukast were not at an increased risk of developing ADHD. Nevertheless, validation of our retrospective survey requires further prospective study.

Environmental risk factors, protective factors, and peripheral biomarkers for ADHD: an umbrella review

BACKGROUND

Many potential environmental risk factors, environmental protective factors, and peripheral biomarkers for ADHD have been investigated, but the consistency and magnitude of their effects are unclear. We aimed to systematically appraise the published evidence of association between potential risk factors, protective factors, or peripheral biomarkers, and ADHD.

METHODS

In this umbrella review of meta-analyses, we searched PubMed including MEDLINE, Embase, and the Cochrane Database of Systematic Reviews, from database inception to Oct 31, 2019, and screened the references of relevant articles. We included systematic reviews that provided meta-analyses of observational studies that examined associations of potential environmental risk factors, environmental protective factors, or peripheral biomarkers with diagnosis of ADHD. We included meta-analyses that used categorical ADHD diagnosis criteria according to DSM, hyperkinetic disorder according to ICD, or criteria that were less rigorous than DSM or ICD, such as self-report. We excluded articles that did not examine environmental risk factors, environmental protective factors, or peripheral biomarkers of ADHD; articles that did not include a meta-analysis; and articles that did not present enough data for re-analysis. We excluded non-human studies, primary studies, genetic studies, and conference abstracts. We calculated summary effect estimates (odds ratio [OR], relative risk [RR], weighted mean difference [WMD], Cohen's d, and Hedges' g), 95% CI, heterogeneity I² statistic, 95% prediction interval, small study effects, and excess significance biases. We did analyses under credibility ceilings, and assessed the quality of the meta-analyses with AMSTAR 2 (A Measurement Tool to Assess Systematic Reviews 2). This study is registered with PROSPERO, number CRD42019145032.

FINDINGS

We identified 1839 articles, of which 35 were eligible for inclusion. These 35 articles yielded 63 meta-analyses encompassing 40 environmental risk factors and environmental protective factors (median cases 16 850, median population 91 954) and 23 peripheral biomarkers (median cases 175, median controls 187). Evidence of association was convincing (class I) for maternal pre-pregnancy obesity (OR 1·63, 95% CI 1·49 to 1·77), childhood eczema (1·31, 1·20 to 1·44), hypertensive disorders during pregnancy (1·29, 1·22 to 1·36), pre-eclampsia (1·28, 1·21 to 1·35), and maternal acetaminophen exposure during pregnancy (RR 1·25, 95% CI 1·17 to 1·34). Evidence of association was highly suggestive (class II) for maternal smoking during pregnancy (OR 1·6, 95% CI 1·45 to 1·76), childhood asthma (1·51, 1·4 to 1·63), maternal pre-pregnancy overweight (1·28, 1·21 to 1·35), and serum vitamin D (WMD -6·93, 95% CI -9·34 to -4·51).

INTERPRETATION

Maternal pre-pregnancy obesity and overweight; pre-eclampsia, hypertension, acetaminophen exposure, and smoking during pregnancy; and childhood atopic diseases were strongly associated with ADHD. Previous familial studies suggest that maternal pre-pregnancy obesity, overweight, and smoking during pregnancy are confounded by familial or genetic factors, and further high-quality studies are therefore required to establish causality.

FUNDING

None.

Asthma and all-cause mortality in children and young adults: a population-based study

BACKGROUND

Studies suggest an increased all-cause mortality among adults with asthma. We aimed to study the relationship between asthma in children and young adults and all-cause mortality, and investigate differences in mortality rate by also having a life-limiting condition (LLC) or by parental socioeconomic status (SES).

METHODS

Included in this register-based study are 2 775 430 individuals born in Sweden between January 1986 and December 2012. We identified asthma cases using the National Patient Register (NPR) and the Prescribed Drug Register. Those with LLC were identified using the NPR. Parental SES at birth (income and education) was retrieved from Statistics Sweden. We estimated the association between asthma and all-cause mortality using a Cox proportional hazards regression model. Effect modification by LLC or parental SES was studied using interaction terms in the adjusted model.

RESULTS

The adjusted hazard rate (adjHR) for all-cause mortality in asthma cases versus non-asthma cases was 1.46 (95% CI 1.33 to 1.62). The highest increased rate appeared to be for those aged 5-15 years. In persons with asthma and without LLC, the adjHR remained increased at 1.33 (95% CI 1.18 to 1.50), but differed (p=0.002) from those with asthma and LLC, with an adjHR of 1.87 (95% CI 1.57 to 2.22). Parental SES did not alter the association (income, p=0.55; education, p=0.83).

CONCLUSION

This study shows that asthma is associated with an increased mortality in children and young adults regardless of LLC or parental SES. Further research is warranted to investigate the possible mechanisms for this association.

Estimated Prevalence of Asthma in US Children With Developmental Disabilities

IMPORTANCE

The prevalence of asthma in US children with various developmental disabilities and delays is unclear, including how estimates vary by ethnic group.

OBJECTIVE

To report asthma prevalence estimates by various disability categories and developmental delays in a diverse sample of the US pediatric population.

DESIGN, SETTING, AND PARTICIPANTS

This population-based cross-sectional study encompassed a total of 71 811 families with children or adolescents aged 0 to 17 years (hereinafter referred to as children) who participated in the 2016 and 2017 National Survey of Children's Health. Data were collected from June 10, 2016, to February 10, 2017, for the 2016 survey and from August 10, 2017, to February 10, 2018, for the 2017 survey. Data were analyzed from September 20, 2019, to April 5, 2020.

EXPOSURES

Developmental disability, including attention-deficit/hyperactivity disorder, autism spectrum disorder, cerebral palsy, seizure, intellectual and/or learning disability, and vision, hearing, and/or speech delay. Delay was defined as not meeting growth milestones with unknown cause.

MAIN OUTCOMES AND MEASURES

Weighted asthma prevalence estimates and 95% CIs were generated for children with and without disabilities.

RESULTS

A total of 71 811 participants (mean [SE] age, 8.6 [0.1] years; 36 800 boys [51.1%; 95% CI, 50.2%-52.0%]; 50 219 non-Hispanic white [51.4%; 95% CI, 50.6%-52.3%]) were included in our final analytical sample, of whom 5687 (7.9%; 95% CI, 7.5%-8.4%) had asthma and 11 426 (15.3%; 95% CI, 14.7%-16.0%) had at least 1 disability. Overall asthma prevalence estimates were 10 percentage points higher in children with a disability (16.1%; 95% CI, 14.3%-17.8%) vs children without a disability (6.5%; 95% CI, 6.0%-6.9%). The odds of asthma were significantly higher in children with a disability (odds ratio [OR], 2.77; 95% CI, 2.39-3.21) or delay (OR, 2.22; 95% CI, 1.78-2.77) vs typically growing children. Adjusted models remained significant for all disability categories (overall adjusted OR, 2.21; 95% CI, 1.87-2.62). Subgroup analyses showed ethnic minorities had a higher prevalence of concurrent asthma and developmental disabilities vs non-Hispanic whites (19.8% [95% CI, 16.6%-23.0%] vs 12.6% [95% CI, 11.1%-14.0%]; P < .001).

CONCLUSIONS AND RELEVANCE

These results suggest that US children with various developmental disabilities or delay may have higher odds for developing asthma vs their typically developing peers. These findings support asthma screening in pediatric health care settings among patients with developmental disabilities and delays, particularly among those from ethnic minority backgrounds. In addition, very young children with asthma should be screened for disabilities and delays, because temporality cannot be determined by the current data source and analytical approach.

The nature and nurture of ADHD and its comorbidities: A narrative review on twin studies

Attention-deficit/hyperactivity disorder (ADHD) is a common neurodevelopmental disorder in children worldwide, and also the recognition of its persistence into adulthood is increasing. While ADHD in childhood is highly heritable and mostly driven by familial factors, during adulthood it appears to show a lower heritability, even if there is not total agreement on this yet. This disorder often co-occurs with many other conditions, which also vary across the different stages of development, and several studies have used the twin design to investigate these comorbidities, giving valuable insights into the origins of the observed co-occurrence. This review aims to summarize the main results of twin research, according to the following domains: individual traits, cognitive impairment, behavioral manifestations, clinical conditions and psychosocial risk factors. Individual features seem to play a role in this symptomatology and include personality traits such as negative emotionality, personality disorders and temperamental dimensions with a predominance of novelty seeking. At a lower level, ADHD is associated with both functional and anatomic brain characteristics. ADHD is also associated with some forms of cognitive impairment, such as sluggish cognitive tempo, and learning disabilities, with a specific predisposition to reading disability. In addition, ADHD is strongly associated with externalizing disorders such as conduct disorder and oppositional defiant disorder, and some behavioral outcomes, particularly substance use and abuse both in adolescence and adulthood. Moreover, ADHD symptoms often overlap with other psychological disorders, namely affective and internalizing disorders, as well as autism spectrum disorder and autistic-like traits in a wider sense. Notably, a genetic overlap has been found between asthma and ADHD, particularly with respect to hyperactivity/impulsivity dimensions. ADHD also appears to represent a risk factor for disordered eating, and, more specifically, for binge eating and bulimia nervosa. Finally, among psychosocial factors, an association has been proposed between childhood maltreatment and ADHD symptoms.

Reduced Attention in Former Smokers with and without COPD

BACKGROUND

Attention difficulties are often reported by patients with chronic obstructive pulmonary disease (COPD); however, limited research exists using objective tests designed specifically to measure attention in this population. This study aimed to (1) identify specific attention deficits in COPD and (2) determine which demographic/clinical characteristics are associated with reduced attention.

METHODS

Eighty-four former smokers (53 COPD, 31 no COPD) completed questionnaires, pulmonary function testing, and the Conner's Continuous Performance Test II (CPT-II). Participants with and without COPD were compared on CPT-II measures of inattention, impulsivity, and vigilance. CPT-II measures that differed significantly between the two groups were further examined using hierarchical regression modeling. Demographic/clinical characteristics were entered into models with attention as the dependent variable.

RESULTS

Participants with COPD performed worse than those without COPD on CPT measures of inattention and impulsivity (i.e., detectability [discrimination of target from non-target stimuli], perseverations [reaction time under 100 ms], omissions [target stimuli response failures], and commissions [responses to non-target stimuli]). More severe COPD (measured by greater airflow limitation) was associated with poorer ability to detect targets vs. foils and perseverative responding after adjusting for age and other covariates in the model.

CONCLUSION

Former smokers with COPD experience problems with attention that go beyond slowed processing speed, including aspects of inattention and impulsivity. Clinicians should be aware that greater airflow limitation and older age are associated with attention difficulties, as this may impact functioning.

Antibiotic Exposure in the First Year of Life and the Risk of Attention-Deficit/Hyperactivity Disorder: A Population-Based Cohort Study

Early childhood antibiotic exposure induces changes in gut microbiota reportedly associated with the development of attention-deficit/hyperactivity disorder (ADHD). We conducted a population-based cohort study to examine the association between antibiotic use in the first year of life and ADHD risk. We included children born in Manitoba, Canada, between 1998 and 2017. Exposure was defined as having filled 1 or more antibiotic prescriptions during the first year of life. ADHD diagnosis was identified in hospital abstracts, physician visits, or drug dispensations. Risk of developing ADHD was estimated using Cox proportional hazards regression in a high-dimensional propensity score-matched cohort (n = 69,738) and a sibling cohort (n = 67,671). ADHD risk was not associated with antibiotic exposure in the matched-cohort (hazard ratio = 1.02, 95% confidence interval: 0.97, 1.08) or in the sibling cohort (hazard ratio = 0.96, 95% confidence interval: 0.89, 1.03). In secondary analyses of the matched cohort, ADHD risk increase was observed in those exposed to 4 or more antibiotic courses or a duration longer than 3 weeks. These associations were not observed in the sibling cohort. We concluded that antibiotic exposure in the first year of life does not pose an ADHD risk on a population level.

Associations of atopic dermatitis and asthma with child behaviour: Results from the PROBIT cohort

BACKGROUND

Conflicting findings from studies evaluating associations of allergic disease with child behaviour require longitudinal studies to resolve.

OBJECTIVE

To estimate the magnitude of associations of atopic dermatitis (AD) in infancy, and symptoms of asthma and AD at 6.5 years, with child behaviour at 6.5 years.

METHODS

Secondary cohort analysis of the Promotion of Breastfeeding Intervention Trial (PROBIT). PROBIT enrolled 17 046 infants at birth and followed them up at 6.5 years (n = 13 889). Study paediatricians collected data on infantile AD at repeated follow-up examinations during the first year of life. At 6.5 years, paediatricians performed skin prick tests and parents reported asthma and AD symptoms during the prior year. In addition, parents and teachers completed the Strength and Difficulties Questionnaire, which includes scales on hyperactivity/inattention, emotional problems, conduct problems, peer problems and prosocial behaviours.

RESULTS

Physician-diagnosed AD in the first year of life was not associated with increased risk for behavioural problems at 6.5 years. Emotional problems at 6.5 years were more common among children with AD symptoms (OR: 2.24, 95% CI: 1.62-3.12) and asthma symptoms (OR: 1.45; 95% CI: 1.07-1.96) during the past year at 6.5 years and ORs for children with symptoms of more severe AD and asthma were also higher. AD in the past year was also associated with probable hyperactivity/inattention disorder at 6.5 years (OR: 2.05; 95% CI: 1.09-3.84). Other subscales of the SDQ were not related to asthma or AD symptoms during the past year.

CONCLUSIONS AND CLINICAL RELEVANCE

Children with AD symptoms were at higher risk for concomitant hyperactivity/inattention and emotional disorder, and children with asthma symptoms were at higher risk of having concomitant emotional problems. However, AD during infancy did not predict childhood behaviours.

Obese- and allergic-related asthma phenotypes among children across the United States

OBJECTIVES

Pediatric asthma is heterogeneous with phenotypes that reflect differing underlying inflammation and pathophysiology. Little is known about the national prevalence of certain obesity- and allergy-related asthma phenotypes or associated characteristics. We therefore assessed the national prevalence, risk factors, and caregiver-reported severity of four asthma phenotypes: not-allergic-not-obese, allergic-not-obese, obese-not-allergic, and allergic-and-obese.

METHODS

We analyzed data from the 2007-2008 National Survey of Children's Health (NSCH) of 10-17 year-olds with caregiver-reported asthma. We described sociodemographic and health risk factors of each phenotype and then applied logistic and ordinal regression models to identify associated risk factors and level of severity of the phenotypes.

RESULTS

Among 4427 children with asthma in this NSCH cohort, the association between race and phenotype was statistically significant (p < 0.0001); white children with asthma were most likely to have allergic-not-obese asthma while black and Hispanic children with asthma were most likely to have the obese-nonallergic phenotype (p < 0.001). Attention-deficit disorder/attention-deficit hyperactivity disorder was more likely to be present in allergic-not-obese children (odds ratio (OR) 1.50, confidence interval (CI) 1.14-1.98, p = 0.004). The phenotype with the highest risk for more severe compared to mild asthma was the obese-and-allergic asthma phenotype (OR 3.34, CI 2.23-5.01, p < 0.001).

CONCLUSIONS

Allergic-not-obese asthma comprised half of our studied asthma phenotypes, while obesity-related asthma (with or without allergic components) comprised one-fifth of asthma phenotypes in this cohort representative of the US population. Children with both obese and allergic asthma are most likely to have severe asthma. Future management of childhood asthma might consider more tailoring of treatment and management plans based upon different childhood asthma phenotypes.

Neurocognitive disorders and sleep in children with primary ciliary dyskinesia

BACKGROUND

Primary ciliary dyskinesia (PCD) patients have higher incidence of sleep disordered breathing which lead neurocognitive impairments such as attention-deficit/hyperactivity disorder (ADHD). It may effect academic performance of children and may cause impairment in emotional relationships. This study aim to evaluate hyperactivity and attention deficiency in PCD patients and investigate the relationship between sleep and hyperactivity and attention deficiency in PCD patients.

METHOD

Fifteen PCD patients aged 8-18 years and 31 age-matched healthy controls were compared. Ear, nose, and throat examination and home sleep testing were performed in PCD patients. Pediatric sleep questionnaire, Conners' Parents and Teacher scale and Stroop test were applied in both groups in order to investigate the relation between sleep disordered breathing and ADHD in PCD children.

RESULTS

PCD patients had chronic rhinosinusitis (100%), tonsillar hypertrophy (80%) and adenoidal hypertrophy (60%). FEF25-75 was low in pulmonary function test. Sixty percent of the PCD patients had mild obstructive sleep apnea syndrome in home sleep testing. Mean AHI was 1.54 ± 0.27. Compared with the controls PCD patients had higher PSQ scores. Hyperactivity scores on Conners' Parents scale and inattention findings in Stroop test were higher in PCD patients than the healthy controls (P < 0.05).

CONCLUSION

Most of PCD children had mild obstructive sleep apnea syndrome. Hyperactivity and inattention findings were higher in PCD patients. Sleep disordered breathing assessment should be a routine part of PCD patients management and these patients should be carefully monitored in terms of hyperactivity and inattention.

Association between attention deficit hyperactivity disorder and asthma: a systematic review and meta-analysis and a Swedish population-based study

BACKGROUND

Several studies have assessed the possible association between attention deficit hyperactivity disorder (ADHD) and asthma. However, existing evidence is inconclusive as to whether this association remains after controlling for possible important confounders. To fill this knowledge gap, we did a systematic review and meta-analysis, followed by a population-based study.

METHODS

For the systematic review and meta-analysis, we searched PubMed, PsycINFO, Embase, Embase Classic, Ovid MEDLINE, and Web of Knowledge databases up to Oct 31, 2017, for observational studies allowing estimation of the association between asthma and ADHD. No restrictions to date, language, or article type were applied. Unpublished data were collected from authors of the identified studies. We extracted unadjusted and adjusted odds ratios (ORs) from the identified studies and calculated ORs when they were not reported. We assessed study quality using the Newcastle-Ottawa Scale and study heterogeneity using I² statistics. A random-effects model was used to calculate pooled ORs. The systematic review is registered with PROSPERO (CRD42017073368). To address the fact that the ORs obtained in the meta-analysis were adjusted for confounders that inevitably varied across studies, we did a population-based study of individuals in multiple national registers in Sweden. We calculated an unadjusted OR and an OR that was simultaneously adjusted for all confounders identified in a directed acyclic graph based on the studies of asthma and ADHD identified in our systematic review.

FINDINGS

We identified 2649 potentially eligible citations, from which we obtained 49 datasets including a total of 210 363 participants with ADHD and 3 115 168 without. The pooled unadjusted OR was 1·66 (95% CI 1·22-2·26; I² =99·47) and the pooled adjusted OR was 1·53 (1·41-1·65; I² =50·76), indicating a significant association between asthma and ADHD. Possible lack of representativeness of the study population was detected with the Newcastle-Ottawa Scale in 42 of 49 datasets. In the population-based study, we included 1 575 377 individuals born between Jan 1, 1992, and Dec 31, 2006, of whom 259 253 (16·5%) had asthma and 57 957 (3·7%) had ADHD. Asthma was significantly associated with ADHD (OR 1·60, 95% CI 1·57-1·63) in the crude model adjusting for sex and year of birth, and this association remained significant after simultaneous adjustment for all covariates (1·45, 1·41-1·48).

INTERPRETATION

The combined results of the meta-analysis and the population-based study support a significant association between asthma and ADHD, which remained even after simultaneously controlling for several possible confounders in the population-based study. Awareness of this association might help to reduce delay in the diagnosis of both ADHD and asthma.

FUNDING

Swedish Research Council and Shire International GmbH.

Attention Deficit Hyperactivity Disorder in Childhood: Healthcare Use in a Danish Birth Cohort during the First 12 Years of Life

OBJECTIVES

To compare the mean number of medical and psychiatric hospital-based services in children with and without attention deficit hyperactivity disorder (ADHD) and to assess the effect of ADHD on hospital-based service use, including child-, parental-, and socioeconomic-related risk factors.

STUDY DESIGN

A Danish birth cohort was followed through 12 years, and children with ADHD were identified using Danish nationwide registries. Poisson regression analyses were used to assess the association of ADHD with service use and to adjust for a comprehensive set of explanatory variables.

RESULTS

Children diagnosed with ADHD used more medical and psychiatric hospital-based healthcare than those without ADHD. In children with ADHD, intellectual disability and parental psychiatric disorder were associated with increased medical and psychiatric service use. Low birth weight and low gestational age were associated with increased medical service use. Psychiatric comorbidity and having a divorced or single parent were associated with increased psychiatric service use.

CONCLUSIONS

ADHD independently affected medical and psychiatric hospital-based service use even when adjusting for a comprehensive set of explanatory variables. However, the pattern of medical and psychiatric hospital-based service use is complex and cannot exclusively be explained by the child-, parental-, and socioeconomic-related variables examined in this study.

Developments in the field of clinical allergy in 2015 through the eyes of Clinical and Experimental Allergy

In the second of two papers, we describe developments in the field of clinical allergy as documented by Clinical and Experimental Allergy in 2015. Epidemiology, clinical allergy, asthma and rhinitis are all covered.

Attention deficit hyperactivity disorder may be a highly inflammation and immune-associated disease (Review)

Attention deficit hyperactivity disorder (ADHD) is a common behavioral disorder. Previous research has indicated that genetic factors, family education, environment and dietary habits are associated with ADHD. It has been determined that in China many children with ADHD also have allergic rhinitis or asthma. These children are more susceptible to the common cold or upper respiratory infections compared with normal healthy children. Additionally, the common cold or an upper respiratory infection may lead to disease recurrence or worsen the symptoms in these children. Previous studies have determined that ADHD may have a close association with allergic disease. Based on the clinically observed phenomenon and previous studies, it was hypothesized that ADHD is a high inflammation and immune‑associated disease. Therefore, the authors designed clinical and animal experiments to test this hypothesis in the future. Immune system disorders may be a novel part of the etiology of ADHD. The current report may have implications for future clinical practice.

ADHD and Everyday Life: Healthcare as a Significant Lifeline

AIM

The aim of this qualitative study was to explore parental experiences of how healthcare practices and healthcare professionals in hospital clinics in Denmark influence everyday life of parents with a child with ADHD.

DESIGN AND METHODS

The methodology was focused ethnography. Participant observation and interviews were used as the primary data collection methods. Fifteen families of children with ADHD were included from somatic and psychiatric hospital clinics.

RESULTS

Three main themes emerged from the experiences of the families: When the house of cards collapses in everyday life, Treading water before and after receiving the ADHD diagnosis, and Healthcare as a significant lifeline.

CONCLUSIONS

Accessibility to healthcare, trusting relationships and healthcare professionals recognizing how ADHD pervades all aspects of everyday life appear to be important factors in providing a lifeline for parents to help them regain confidence and control in disruptive phases. The parents depend on help from healthcare professionals and family-centred care to manage the complex challenges in everyday life.

The influence of comorbid asthma on the severity of symptoms in children with attention-deficit hyperactivity disorder

OBJECTIVE

The current study examined the association between asthma and attention-deficit hyperactivity disorder (ADHD) symptoms in a clinical pediatric sample.

METHODS

Demographic and neuropsychological data for children with a billing diagnosis of ADHD were extracted from a clinical database. Families completed standard rating scales. Seventy-one patients with a co-morbid asthma diagnosis were identified and matched by age to a group of 71 patients with only ADHD.

RESULTS

Children with asthma and ADHD were more likely to display clinically elevated levels of hyperactivity, externalizing behaviors, anxiety, and hyperactive/impulsive behaviors compared to children with ADHD alone. Boys with asthma and ADHD had more symptoms than boys with only ADHD of somatization and emotional internalizing, while girls with asthma and ADHD had more symptoms of hyperactivity/impulsivity, conduct problems, anxiety, and emotional internalizing compared to girls with only ADHD.

CONCLUSIONS

Findings suggest that in children with ADHD, co-morbid asthma is associated with increased behavioral and internalizing symptoms, with distinct gender differences present. Increased behavioral and internalizing symptoms seen in children with both asthma and ADHD may be due to the burden of their medical condition. No difference was found on cognitive variables, suggesting chronic hypoxia may be less influential in explaining these differences. Future research should determine the specific mechanisms of these differences.

Association between preschool eczema and medication for attention-deficit/hyperactivity disorder in school age

BACKGROUND

Several studies show an association between eczema and attention-deficit/hyperactivity disorder (ADHD) in childhood, but the mechanisms and time sequence remain unclear. Information on the association between eczema and other disorders involving the central nervous system (CNS) is limited. The aim was to explore whether preschool eczema was associated with ADHD or other CNS-associated disorders requiring pharmacotherapy at school age and to analyze whether eczema at other ages of childhood was associated with medication for ADHD.

METHODS

From a Swedish birth cohort, 3606 children were included in the analyses. At 1, 2, 4, 8, 12, and 16 years of age, their parents answered questionnaires regarding eczema the last year. Information on prescribed medications during school age (10-18 years of age) was derived by record linkage to the Swedish Prescribed Drug Register.

RESULTS

A total of 1178 (32.7%) of the children had preschool eczema (eczema at 1, 2, and/or 4 years), and 162 (4.5%) of the children had dispensed ADHD medication at school age. Preschool eczema was not associated with ADHD medication at school age (crude odds ratio 1.16; 95% Confidence Intervals: 0.83-1.61). There was no significant association between preschool eczema and use of antidepressants, migraine drugs, or anti-epileptics at school age. Infantile eczema, school-age eczema, and eczema ever up to 16 years of age were not associated with ADHD medication at school age.

CONCLUSIONS

In this large birth cohort, there were no significant associations between preschool eczema and medications for ADHD, depression/anxiety/phobia, migraine, or epilepsy at school age.

Association of atopic diseases and attention-deficit/hyperactivity disorder: A systematic review and meta-analyses

Over the last decades, the hypothesis has been raised that an atopic response could lead to the development of attention-deficit/hyperactivity disorder (ADHD). This study systematically reviews the observational cross-sectional and longitudinal studies that assessed the association between atopic disorders including asthma, atopic eczema, allergic rhinitis, and ADHD in children and adolescents. For longitudinal studies, a weighted Mantel-Haenszel odds ratio of these associations was estimated. The majority of cross-sectional and longitudinal studies reported a statistically significant positive association. The meta-analysis of longitudinal studies revealed an overall weighted odds ratio for asthma of 1.34 (95% confidence interval [CI] 1.24-1.44), 1.32 (95% CI 1.20-1.45) for atopic eczema, and 1.52 (95% CI 1.43-1.63) for allergic rhinitis. Heterogeneity of study data was low (I²: 0%, p=0.46 and p=0.64, respectively) for both studies examining asthma and eczema but substantial for rhinitis studies (I²: 82%, p=0.004). This current systematic review provides strong evidence that ADHD is associated with atopic diseases and that individuals have a 30% to 50% greater chance of developing ADHD compared to controls.

Attention Deficit Disorder and Allergic Rhinitis: Are They Related?

The association between ADHD and allergy remains controversial. Our previous findings suggest that nerve growth factor may link the nervous and immune systems. The primary objective of this study was to determine if a combination of cetirizine + methylphenidate is effective in children with comorbid ADHD and allergic rhinitis. We also examined the role of nerve growth factor in these comorbidities. Our randomized, double-blind, placebo-controlled, crossover study enrolled 38 children diagnosed with comorbid ADHD and allergy using cetirizine (n = 12), sustained-release methylphenidate (n = 12), or cetirizine + methylphenidate (n = 14). Endpoints compared baseline to posttreatment evaluations for allergic rhinitis and ADHD scores. Serum nerve growth factor levels were measured using ELISA. For allergy endpoints, combination therapy produced results superior to individual therapy. For ADHD, similar scores were achieved for individual therapy; however, combination therapy resulted in improved scores. Nerve growth factor levels were downregulated following this trend. We conclude that ADHD and allergic rhinitis may have common mechanism and represent a comorbid condition that links the nervous system to the immune system. Further studies are needed.

Association between medication prescription for atopic diseases and attention-deficit/hyperactivity disorder

BACKGROUND

Data on the association between atopic diseases and attention-deficit/hyperactivity disorder (ADHD) have been inconclusive.

OBJECTIVE

To assess whether children with drug-treated ADHD are more likely to receive treatment for asthma, allergic rhinitis, or eczema before the start of ADHD medication use compared with controls and to examine the effect of parents receiving medication for ADHD and atopic diseases on ADHD medication use in their offspring.

METHODS

We conducted a retrospective nested case-control study among children (6-12 years of age) using the Groningen University prescription database. Cases were defined as children with at least 2 prescriptions of methylphenidate within 12 months. For each case, 4 controls were matched on age, sex, and regional area code. Parental prescription data were linked to cases and controls to assess the influence of parents receiving medication for ADHD and atopic diseases on ADHD medication use in their offspring.

RESULTS

We identified 4257 cases and 17,028 matched controls. Drug treatment for asthma, allergic rhinitis, and eczema was more common in cases than controls (adjusted odds ratios [aORs], 1.4 [95% confidence interval (CI), 1.3-1.6], 1.4 [95% CI, 1.1-1.8], and 1.3 [95% CI, 1.1-1.5], respectively). Medication for allergic rhinitis and asthma among parents was associated with ADHD treatment in their children (aORs, 1.3 [95% CI, 1.1-1.5] and 1.2 [95% CI, 1.1-1.3], respectively).

CONCLUSION

This study provides further evidence to support the hypothesis that atopic diseases are associated with ADHD. The parental-offspring association suggests a possible genetic and/or environmental component.