Subthreshold and threshold attention deficit hyperactivity disorder symptoms in childhood: psychosocial outcomes in adolescence in boys and girls

Sex Differences in Diagnosis and Treatment Timing of Comorbid Depression/Anxiety and Disease Subtypes in Patients With ADHD: A Database Study

OBJECTIVE

Our study examined the impact of sex, ADHD subtype, and comorbid illnesses (depression/anxiety) on the timing of diagnosis and treatment for ADHD.

METHOD

To analyze ADHD patients, four health databases were used to assess subtype, comorbid mood, and antidepressant or anxiolytic drug exposure. Analyses were stratified by sex and age. Standardized mean differences measured intergroup differences.

RESULTS

Females with ADHD were identified at older ages and had higher rates of depression and anxiety diagnoses and treatments before and after their initial ADHD diagnosis. Predominantly inattentive ADHD patients were diagnosed later and more likely to receive mood disorder diagnosis and treatment than hyperactive impulsive ADHD patients.

CONCLUSIONS

Results suggest a more complex ADHD presentation in females, potentially causing late diagnosis and delayed treatment.

Prediction of internalizing and externalizing symptoms in late childhood from attention-deficit/hyperactivity disorder symptoms in early childhood

Limited analyses based on national samples have assessed whether early attention-deficit/hyperactivity disorder (ADHD) symptoms predict later internalizing and externalizing symptoms in youth and the influence of sex and pubertal timing on subsequent psychiatric symptoms. This study analyzed data (n = 2818) from the Environmental influences on Child Health Outcomes Program national cohort. Analyses used data from early childhood (mean age = 5.3 years) utilizing parent-reported ADHD symptoms to predict rates of internalizing and externalizing symptoms from late childhood/adolescence (mean age = 11.9 years). Within a subsample age at peak height velocity (APHV) acted as a proxy to assess pubertal timing from early childhood (mean age = 5.4 years) to adolescence (mean age = 12.3 years). Early-childhood ADHD symptoms predicted later psychiatric symptoms, including anxiety, depression, aggressive behavior, conduct problems, oppositional defiant disorder, and rule-breaking behavior. Earlier APHV was associated with increased Conduct Disorder symptoms from late childhood to adolescence for females only. A stronger relation between ADHD symptoms and later aggression was observed in females with earlier APHV, whereas this same pattern with aggression, conduct problems and depression was observed in males with later APHV. Clinicians should consider that both young girls and boys with elevated ADHD symptoms, particularly with off-set pubertal timing, may be at risk for later psychiatric symptoms.

The High Rates of Comorbidity among Neurodevelopmental Disorders: Reconsidering the Clinical Utility of Distinct Diagnostic Categories

The boundaries between neurodevelopmental disorders are often indistinct, even among specialists. But do these boundaries exist, or do experts struggle to distinguish and categorize symptoms in order to arrive at a dominant diagnosis while comorbidity continually leaves questions about where each disorder ends and begins? What should be reconsidered? The introduction of the term 'spectrum of neurodevelopmental disorders' could pave the way for a re-appraisal of the clinical continuum of neurodevelopmental disorders. This study aims to highlight the problems that emerge in the field of the differential diagnosis of neurodevelopmental disorders and propose a renegotiation of the distinctiveness criteria.

Association between relative age at school and persistence of ADHD in prospective studies: an individual participant data meta-analysis

BACKGROUND

The youngest children in a school class are more likely than the oldest to be diagnosed with ADHD, but this relative age effect is less frequent in older than in younger school-grade children. However, no study has explored the association between relative age and the persistence of ADHD diagnosis at older ages. We aimed to quantify the association between relative age and persistence of ADHD at older ages.

METHODS

For this meta-analysis, we searched MEDLINE, Embase, CINAHL, PsycINFO, and PubPsych up to April 1, 2022, with terms related to "cohort" and "ADHD" with no date, publication type, or language restrictions. We gathered individual participant data from prospective cohorts that included at least ten children identified with ADHD before age 10 years. ADHD was defined by either a clinical diagnosis or symptoms exceeding clinical cutoffs. Relative age was recorded as the month of birth in relation to the school-entry cutoff date. Study authors were invited to share raw data or to apply a script to analyse data locally and generate anonymised results. Our outcome was ADHD status at a diagnostic reassessment, conducted at least 4 years after the initial assessment and after age 10 years. No information on sex, gender, or ethnicity was collected. We did a two-stage random-effects individual participant data meta-analysis to assess the association of relative age with persistence of ADHD at follow-up. This study was registered with PROSPERO, CRD42020212650.

FINDINGS

Of 33 119 studies generated by our search, we identified 130 eligible unique studies and were able to gather individual participant data from 57 prospective studies following up 6504 children with ADHD. After exclusion of 16 studies in regions with a flexible school entry system that did not allow confident linkage of birthdate to relative age, the primary analysis included 41 studies in 15 countries following up 4708 children for a period of 4 to 33 years. We found that younger relative age was not statistically significantly associated with ADHD persistence at follow-up (odds ratio 1·02, 95% CI 0·99-1·06; p=0·19). We observed statistically significant heterogeneity in our model (Q=75·82, p=0·0011, I2=45%). Participant-level sensitivity analyses showed similar results in cohorts with a robust relative age effect at baseline and when restricting to cohorts involving children with a clinical diagnosis of ADHD or with a follow-up duration of more than 10 years.

INTERPRETATION

The diagnosis of ADHD in younger children in a class is no more likely to be disconfirmed over time than that of older children in the class. One interpretation is that the relative age effect decreases the likelihood of children of older relative age receiving a diagnosis of ADHD, and another is that assigning a diagnostic label of ADHD leads to unexplored carryover effects of the initial diagnosis that persist over time. Future studies should be conducted to explore these interpretations further.

FUNDING

None.

Facial emotion recognition in children and youth with attention-deficit/hyperactivity disorder and irritability

The ability to recognize emotions evident in people's faces contributes to social functioning and might be affected by ADHD and irritability. Given their high co-occurrence, we examined the relative contribution of ADHD and irritability to facial emotion recognition (FER). We hypothesized that irritability but not ADHD traits would predict increased likelihood of misrecognizing emotions as negative, and that FER performance would explain the association of ADHD and irritability traits with social skills. FER was measured using the Reading the Mind in the Eyes Test (RMET) in children (6-14 years old) referred for ADHD assessment (n = 304) and healthy controls (n = 128). ADHD, irritability and social skills were measured using parent ratings. We used repeated measure logistics regression, comparing the effects across emotion valence of images (i.e., neutral/positive/negative). High irritability but not ADHD diagnosis predicted lower RMET accuracy. ADHD traits predicted lower RMET accuracy in younger but not older participants, whereas irritability predicted poorer accuracy at all ages. ADHD traits predicted lower RMET accuracy across all emotion valences, whereas irritability predicted increased probability of misrecognizing neutral and positive but not negative emotions. Irritability did not increase the probability for erroneously recognizing emotions as negative. ADHD and irritability traits fully explained the association between RMET and social skills. ADHD and irritability traits might impact the ability to identify emotions portrayed in faces. However, irritability traits appear to selectively impair recognition of neutral and positive but not negative emotions. ADHD and irritability are important when examining the link between FER and social difficulties.

Atypical procedural learning skills in children with Developmental Coordination Disorder

We investigated the procedural learning deficit hypothesis in Developmental Coordination Disorder (DCD) while controlling for global performance such as slower reaction times (RTs) and variability. Procedural (sequence) learning was assessed in 31 children with DCD and 31 age-matched typically developing (TD) children through a serial reaction time task (SRTT). Sequential and random trial conditions were intermixed within five training epochs. Two repeated measures ANOVAs were conducted on a Sequence-Specific Learning Index (SSLI) and a Global Performance Index (GPI, speed/accuracy measure) with Epoch (for SSLI and GPI) and Condition (for GPI) as within-subjects factors, and Group as between-subjects factor. Controlling for RTs differences through normalized RTs, revealed a global reduction of SSLI in children with DCD compared with TD peers suggesting reduced sequence learning skills in DCD. Still, a significant Group x Condition interaction observed on GPI indicated that children from both groups were able to discriminate between sequential and random trials. DCD presented reduced procedural learning skills after controlling for global performance. This finding highlights the importance of considering the general functioning of the child while assessing learning skills in patients.

The Clinical Manifestation, Executive Dysfunction, and Caregiver Strain in Subthreshold Attention-Deficit/Hyperactivity Disorder

OBJECTIVE

Subthreshold attention-deficit/hyperactivity disorder (ADHD) has been suggested to be a "morbid condition" which also needs medical attention.

METHODS

The present study recruited 89 children with subthreshold ADHD (sADHD), 115 children with diagnosed ADHD (cADHD), and 79 healthy controls (HC) to explore the clinical manifestation, executive functions (EFs) of sADHD, and the caregiver strain. The clinical manifestation was evaluated through clinical interviews and parent-reports. Executive functions were assessed both experimentally and ecologically. Caregiver strain was measured by a parent-reported questionnaire.

RESULTS

For the clinical manifestation, both sADHD and cADHD indicated impairments when compared with HC. The comorbidities and the scaled symptoms indicated that the externalizing behaviors were relatively less serious in sADHD than cADHD, whereas the internalizing behaviors between two groups were comparable. For ecological EFs, sADHD scored between cADHD and HC in inhibition and working memory. For experimental EFs, sADHD was comparable to cADHD in inhibition, shifting, and was worse than cADHD in verbal working memory. For the caregiver strain, all scores of sADHD were between that in cADHD and that in HC.

CONCLUSION

Our present findings supported the suggestion of subthreshold ADHD as "morbid condition," which should be treated with caution in clinical practice, especially for the internalizing behaviors and some key components of EFs.

Generalizable prediction of childhood ADHD symptoms from neurocognitive testing and youth characteristics

Childhood attention-deficit/hyperactivity disorder (ADHD) symptoms are believed to result from disrupted neurocognitive development. However, evidence for the clinical and predictive value of neurocognitive assessments in this context has been mixed, and there have been no large-scale efforts to quantify their potential for use in generalizable models that predict individuals' ADHD symptoms in new data. Using data drawn from the Adolescent Brain Cognitive Development Study (ABCD), a consortium that recruited a diverse sample of over 10,000 youth (ages 9-10 at baseline) across 21 U.S. sites, we develop and test cross-validated machine learning models for predicting youths' ADHD symptoms using neurocognitive abilities, demographics, and child and family characteristics. Models used baseline demographic and biometric measures, geocoded neighborhood data, youth reports of child and family characteristics, and neurocognitive tests to predict parent- and teacher-reported ADHD symptoms at the 1-year and 2-year follow-up time points. Predictive models explained 15-20% of the variance in 1-year ADHD symptoms for ABCD Study sites that were left out of the model-fitting process and 12-13% of the variance in 2-year ADHD symptoms. Models displayed high generalizability across study sites and trivial loss of predictive power when transferred from training data to left-out data. Features from multiple domains contributed meaningfully to prediction, including neurocognition, sex, self-reported impulsivity, parental monitoring, and screen time. This work quantifies the information value of neurocognitive abilities and other child characteristics for predicting ADHD symptoms and provides a foundational method for predicting individual youths' symptoms in new data across contexts.

Anxiety, mood, and substance use disorders in adult men and women with and without Attention-Deficit/Hyperactivity Disorder: a substantive and methodological overview

Knowledge on psychiatric comorbidity in adult ADHD is essential for prevention, detection, and treatment of these conditions. This review (1) focuses on large studies (n> 10,000; surveys, claims data, population registries) to identify (a) overall, (b) sex- and (c) age-specific patterns of comorbidity of anxiety disorders (ADs), major depressive disorder (MDD), bipolar disorder (BD) and substance use disorders (SUDs) in adults with ADHD relative to adults without ADHD; and (2) describes methodological challenges relating to establishing comorbidity in ADHD in adults as well as priorities for future research. Meta-analyses (ADHD: n=550,748; no ADHD n=14,546,814) yielded pooled odds ratios of 5.0(CI:3.29-7.46) for AD, 4.5(CI:2.44-8.34) for MDD, 8.7(CI:5.47-13.89) for BD and 4.6(CI:2.72-7.80) for SUDs, indicating strong differences in adults with compared to adults without ADHD. Moderation by sex was not found: high comorbidity held for both men and women with sex-specific patterns as in the general population: higher prevalences of ADs, MDD and BD in women and a higher prevalence of SUDs in men. Insufficient data on different phases of the adult lifespan prevented conclusions on developmental changes in comorbidity. We discuss methodological challenges, knowledge gaps, and future research priorities.

Substance-Related Problems in Adolescents with ADHD-Diagnoses: The Importance of Self-Reported Conduct Problems

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) is a known risk factor for substance-related problems (SRP) during adolescence, but the nature of this relationship and the importance of co-occurring conduct problems are not fully understood.

METHODS

Data stem from a linked dataset between a large population-based survey conducted in 2012 of Norwegian adolescents aged 16 to 19, and registry-based data from specialized child and adolescent mental health services (n = 9,411).

RESULTS

Adolescents with "ADHD + high conduct problems" had increased risk of SRP (odds ratios = 2.37-10.14). Adolescents with "ADHD only" had very similar risk of SRP as adolescents from the general population with low symptoms of conduct problems. Relative to boys, girls with "ADHD + high conduct problems" appeared to have somewhat higher risk for SRP.

CONCLUSION

The present study suggests that the risk for SRP among adolescent with ADHD is largely driven by co-existing conduct problems.

Transdiagnostic Clinical Staging for Childhood Mental Health: An Adjunctive Tool for Classifying Internalizing and Externalizing Syndromes that Emerge in Children Aged 5-11 Years

Clinical staging is now recognized as a key tool for facilitating innovation in personalized and preventative mental health care. It places a strong emphasis on the salience of indicated prevention, early intervention, and secondary prevention of major mental disorders. By contrast to established models for major mood and psychotic syndromes that emerge after puberty, developments in clinical staging for childhood-onset disorders lags significantly behind. In this article, criteria for a transdiagnostic staging model for those internalizing and externalizing disorders that emerge in childhood is presented. This sits alongside three putative pathophysiological profiles (developmental, circadian, and anxious-arousal) that may underpin these common illness trajectories. Given available evidence, we argue that it is now timely to develop a transdiagnostic staging model for childhood-onset syndromes. It is further argued that a transdiagnostic staging model has the potential to capture more precisely the dimensional, fluctuating developmental patterns of illness progression of childhood psychopathology. Given potential improvements in modelling etiological processes, and delivering more personalized interventions, transdiagnostic clinical staging for childhood holds much promise for assisting to improve outcomes. We finish by presenting an agenda for research in developments of transdiagnostic clinical staging for childhood mental health.

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

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

Cognitive Control Deficits in Children With Subthreshold Attention-Deficit/Hyperactivity Disorder

Subthreshold Attention-Deficit/Hyperactivity Disorder (ADHD) is defined as a neurobiological condition with some core inattentive or hyperactive/impulsive symptoms of ADHD which do not meet the full diagnosis clinically. Although it has been well documented that deficits in cognitive control, a high-level cognitive construct closely related to attention, are frequently found among children with ADHD, whether subthreshold ADHD is also associated with similar deficits remains unclear. In this study, we examined the attention functions and the cognitive control capacity (CCC) in children with ADHD (n = 39), those with subthreshold ADHD (n = 34), and typically developing peers (TD, n = 36). The results showed that the ADHD and subthreshold ADHD groups exhibited similar patterns of the impaired executive function of attention (revealed as an augment in flanker conflict effect) and reduced cognitive control capacity, and no significant difference was found between the two groups. These findings suggest that although children with subthreshold ADHD have not met the full criteria of ADHD, they showed reduced efficiency in cognitive control and attention function, similar to children with ADHD.

Effects of Bacopa monnieri (CDRI 08®) in a population of males exhibiting inattention and hyperactivity aged 6 to 14 years: A randomized, double-blind, placebo-controlled trial

The current study investigated the efficacy of extract of Bacopa monnieri (BM; CDRI 08®) in reducing levels of inattention and hyperactivity in young children. BM has demonstrated improvements in cognitive outcomes in adults, yet little research is available on its effects in younger populations. A 14-week randomized, double-blind, placebo-controlled clinical trial, with placebo run-in and run-out phases, investigated the effects of BM on behavioural, cognitive, mood, and sleep effects in male children aged 6 to 14 years against placebo. One-hundred and twelve participants were recruited into the trial, with 93 datasets available for analysis. No significant behavioural differences were noted between treatment groups. Cognitive outcomes indicated decreased error-making in children taking CDRI 08® (p = .04) and increased speed of reaction time in those taking placebo (p = .04) at study end. Improvements in cognitive flexibility (p = .01), executive functioning (p = .04), interpersonal problems (p = .02), and sleep routine (p = .04) were noted in those consuming CDRI 08® over placebo. CDRI 08® did not improve behavioural outcomes, but may have cognitive, mood and sleep benefits in children aged 6 to 14 years. Further study is required to support the findings presented here.

[Psychoanalytic Treatments without Medication and Behavioral Therapy Treatments with and without Medication in Children with the Diagnosis of ADHD and/or Conduct Disorder]

The controlled, prospective intervention study without randomization with a non-inferiority study design investigates the effectiveness of psychoanalytic treatments without medication in comparison to behavioral therapy treatments with and without medication in children aged 6 to 11 years with a diagnosis of ADHD and/or conduct disorder. 73 children (58 boys and 15 girls) were included in the study. Diagnostics before treatment, at end of treatment and at follow-up after 38 months included a standardized clinical interview (DISYPS-KJ), questionnaires for parents, teachers and children (DISYPS-KJ, CBCL, TRF, CPRS, CTRS, ILK), intelligence test and behavioral observation of the child. Primary outcome criterion was disorder-specific symptom reduction at end of treatment and follow-up. Both treatment groups showed significant symptom reductions at end of treatment and at follow-up. There were no significant differences between treatment groups. Parent and teacher ratings showed significant improvements in both groups at end of treatment and at follow-up on the ADHD index, oppositional behavior, and hyperactivity/impulsivity scales, as well as on the externalizing and internalizing behavior problems scales. Quality of life improved for children in both treatment groups.

Characterisation of neurodevelopmental and psychological outcomes in CHD: a research agenda and recommendations from the cardiac neurodevelopmental outcome collaborative

The Neurodevelopmental and Psychological Outcomes Working Group of the Cardiac Neurodevelopmental Outcome Collaborative was formed in 2018 through support from an R13 grant from the National Heart, Lung, and Blood Institute with the goals of identifying knowledge gaps regarding the neurodevelopmental and psychological outcomes of individuals with CHD and investigations needed to advance science, policy, clinical care, and patient/family outcomes. Accurate characterisation of neurodevelopmental and psychological outcomes in children with CHD will drive improvements in patient and family outcomes through targeted intervention. Decades of research have produced a generalised perspective about neurodevelopmental and psychological outcomes in this heterogeneous population. Future investigations need to shift towards improving methods, measurement, and analyses of outcomes to better inform early identification, prevention, and intervention. Improved definition of underlying developmental, neuropsychological, and social-emotional constructs is needed, with an emphasis on symptom networks and dimensions. Identification of clinically meaningful outcomes that are most important to key stakeholders, including patients, families, schools and providers, is essential, specifically how and which neurodevelopmental differences across the developmental trajectory impact stakeholders. A better understanding of the discontinuity and patterns of neurodevelopment across the lifespan is critical as well, with some areas being more impactful at some ages than others. Finally, the field needs to account for the impact of race/ethnicity, socio-economic status, cultural and linguistic diversity on our measurement, interpretation of data, and approach to intervention and how to improve generalisability to the larger worldwide population of patients and families living with CHD.

Overdiagnosis of Attention-Deficit/Hyperactivity Disorder in Children and Adolescents: A Systematic Scoping Review

IMPORTANCE

Reported increases in attention-deficit/hyperactivity disorder (ADHD) diagnoses are accompanied by growing debate about the underlying factors. Although overdiagnosis is often suggested, no comprehensive evaluation of evidence for or against overdiagnosis has ever been undertaken and is urgently needed to enable evidence-based, patient-centered diagnosis and treatment of ADHD in contemporary health services.

OBJECTIVE

To systematically identify, appraise, and synthesize the evidence on overdiagnosis of ADHD in children and adolescents using a published 5-question framework for detecting overdiagnosis in noncancer conditions.

EVIDENCE REVIEW

This systematic scoping review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) Extension for Scoping Reviews and Joanna Briggs Methodology, including the PRISMA-ScR Checklist. MEDLINE, Embase, PsychINFO, and the Cochrane Library databases were searched for studies published in English between January 1, 1979, and August 21, 2020. Studies of children and adolescents (aged ≤18 years) with ADHD that focused on overdiagnosis plus studies that could be mapped to 1 or more framework question were included. Two researchers independently reviewed all abstracts and full-text articles, and all included studies were assessed for quality.

FINDINGS

Of the 12 267 potentially relevant studies retrieved, 334 (2.7%) were included. Of the 334 studies, 61 (18.3%) were secondary and 273 (81.7%) were primary research articles. Substantial evidence of a reservoir of ADHD was found in 104 studies, providing a potential for diagnoses to increase (question 1). Evidence that actual ADHD diagnosis had increased was found in 45 studies (question 2). Twenty-five studies showed that these additional cases may be on the milder end of the ADHD spectrum (question 3), and 83 studies showed that pharmacological treatment of ADHD was increasing (question 4). A total of 151 studies reported on outcomes of diagnosis and pharmacological treatment (question 5). However, only 5 studies evaluated the critical issue of benefits and harms among the additional, milder cases. These studies supported a hypothesis of diminishing returns in which the harms may outweigh the benefits for youths with milder symptoms.

CONCLUSIONS AND RELEVANCE

This review found evidence of ADHD overdiagnosis and overtreatment in children and adolescents. Evidence gaps remain and future research is needed, in particular research on the long-term benefits and harms of diagnosing and treating ADHD in youths with milder symptoms; therefore, practitioners should be mindful of these knowledge gaps, especially when identifying these individuals and to ensure safe and equitable practice and policy.

Economic Return on Investment of Parent Training Programmes for the Prevention of Child Externalising Behaviour Problems

Economic models to inform decision-making are gaining popularity, especially for preventive interventions. However, there are few estimates of the long-term returns to parenting interventions used to prevent mental health problems in children. Using data from a randomised controlled trial evaluating five indicated parenting interventions for parents of children aged 5-12, we modeled the economic returns resulting from reduced costs in the health care and education sector, and increased long-term productivity in a Swedish setting. Analyses done on the original trial population, and on various sized local community populations indicated positive benefit-cost ratios. Even smaller local authorities would financially break-even, thus interventions were of good value-for-money. Benefit-cost analyses of such interventions may improve the basis for resource allocation within local decision-making.

Investigating causality between liability to ADHD and substance use, and liability to substance use and ADHD risk, using Mendelian randomization

Attention-deficit hyperactivity disorder (ADHD) has consistently been associated with substance use, but the nature of this association is not fully understood. To inform intervention development and public health messages, a vital question is whether there are causal pathways from ADHD to substance use and/or vice versa. We applied bidirectional Mendelian randomization, using summary-level data from the largest available genome-wide association studies (GWAS) on ADHD, smoking (initiation, cigarettes per day, cessation, and a compound measure of lifetime smoking), alcohol use (drinks per week, alcohol problems, and alcohol dependence), cannabis use (initiation), and coffee consumption (cups per day). Genetic variants robustly associated with the "exposure" were selected as instruments and identified in the "outcome" GWAS. Effect estimates from individual genetic variants were combined with inverse-variance weighted regression and five sensitivity analyses (weighted median, weighted mode, MR-Egger, generalized summary data-based MR, and Steiger filtering). We found evidence that liability to ADHD increases likelihood of smoking initiation and heaviness of smoking among smokers, decreases likelihood of smoking cessation, and increases likelihood of cannabis initiation. There was weak evidence that liability to ADHD increases alcohol dependence risk but not drinks per week or alcohol problems. In the other direction, there was weak evidence that smoking initiation increases ADHD risk, but follow-up analyses suggested a high probability of horizontal pleiotropy. There was no clear evidence of causal pathways between ADHD and coffee consumption. Our findings corroborate epidemiological evidence, suggesting causal pathways from liability to ADHD to smoking, cannabis use, and, tentatively, alcohol dependence. Further work is needed to explore the exact mechanisms mediating these causal effects.

Physical activity in early adolescence predicts depressive symptoms 3 years later: A community-based study

BACKGROUND

Physical activity (PA) during adolescence is associated with a wide range of health benefits, including lower levels of internalizing and externalizing problems. Although the association between PA and mental health has been established, there are few prospective studies investigating if the association between PA and internalizing/externalizing symptoms remains after adjustment for the baseline occurrence of such symptoms, and those exploring any sex-specific pattern of the association.

METHODS

Swedish adolescents (N = 1428; mean age = 14.38 years) were assessed and followed up 3 years later. Self-reported data were collected for PA (recoded as low, moderate and high levels), internalizing (depression and anxiety) and externalizing (attention-deficit/hyperactivity disorder and disruptive behaviours) symptoms. A full path analysis was used to determine the main and interaction effects of PA and sex on internalizing/externalizing symptoms 3 years later, adjusting for these symptoms at baseline.

RESULTS

Higher levels of PA were correlated with lower internalizing/externalizing symptoms. In the full path analysis, PA during early adolescence predicted lower levels of depressive symptoms, but not anxiety or externalizing problems, 3 years later. A sex-specific effect of PA on depressive symptoms was found, wherein boys, but not girls, with high levels of PA showed reduced symptoms.

LIMITATIONS

Including parental ratings, diagnostic assessments and objective measures of PA would have provided additional information to the study.

CONCLUSIONS

Low levels of PA during early adolescence are a unique predictor for the development of depressive symptoms among boys. PA should be considered when discussing prevention and treatment for depression in adolescents.

ADHD at Age 7 and Functional Impairments at Age 10

BACKGROUND AND OBJECTIVES

Attention-deficit/hyperactivity disorder (ADHD) cohort studies have typically involved clinical samples and have usually recruited children across wide age ranges, limiting generalizability across complexity and developmental stage. We compared academic, emotional-behavioral and social functioning at age 10, and predictors of outcomes, in a nonreferred cohort of children recruited at age 7, between those with full-syndrome (FS) ADHD and controls with no ADHD.

METHODS

This was a prospective cohort study with a 3-year follow-up period. Children were recruited from 43 socioeconomically diverse schools in Melbourne, Australia. Multi-informant outcomes at age 10 were academic functioning (Wide Range Achievement Test 4; Social Skills Improvement System), emotional-behavioral functioning (Strengths and Difficulties Questionnaire total), and social functioning (Strengths and Difficulties Questionnaire peer problems). Outcomes were compared across the groups by using adjusted random-effects linear regression analyses.

RESULTS

In total, 477 children (62% male) were recruited at a mean (SD) age of 7.3 years (0.4). There were 179 participants with FS ADHD, 86 with ST ADHD, and 212 controls. Sample retention was 78.2% at 3-year follow-up. Both the FS and ST groups were functioning worse than controls on almost all outcome measures. The best predictors of outcome for children with ADHD were working memory (academic outcome, P < .001), ADHD symptom severity (emotional-behavioral outcome, parent: P < .001; teacher: P < .01), and autism spectrum disorder symptoms (emotional-behavioral outcome, parent P = .003; social outcome, parent P = .001).

CONCLUSIONS

Children with FS and ST ADHD at age 7 experience persisting functional impairments across domains at age 10. The predictors identified at age 7 present potential targets for intervention to ameliorate impairments.

ADHD: Current Concepts and Treatments in Children and Adolescents

Attention deficit hyperactivity disorder (ADHD) is among the most frequent disorders within child and adolescent psychiatry, with a prevalence of over 5%. Nosological systems, such as the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5) and the International Classification of Diseases, editions 10 and 11 (ICD-10/11) continue to define ADHD according to behavioral criteria, based on observation and on informant reports. Despite an overwhelming body of research on ADHD over the last 10 to 20 years, valid neurobiological markers or other objective criteria that may lead to unequivocal diagnostic classification are still lacking. On the contrary, the concept of ADHD seems to have become broader and more heterogeneous. Thus, the diagnosis and treatment of ADHD are still challenging for clinicians, necessitating increased reliance on their expertise and experience. The first part of this review presents an overview of the current definitions of the disorder (DSM-5, ICD-10/11). Furthermore, it discusses more controversial aspects of the construct of ADHD, including the dimensional versus categorical approach, alternative ADHD constructs, and aspects pertaining to epidemiology and prevalence. The second part focuses on comorbidities, on the difficulty of distinguishing between "primary" and "secondary" ADHD for purposes of differential diagnosis, and on clinical diagnostic procedures. In the third and most prominent part, an overview of current neurobiological concepts of ADHD is given, including neuropsychological and neurophysiological researches and summaries of current neuroimaging and genetic studies. Finally, treatment options are reviewed, including a discussion of multimodal, pharmacological, and nonpharmacological interventions and their evidence base.

Predicting mental health problems in adolescence using machine learning techniques

BACKGROUND

Predicting which children will go on to develop mental health symptoms as adolescents is critical for early intervention and preventing future, severe negative outcomes. Although many aspects of a child's life, personality, and symptoms have been flagged as indicators, there is currently no model created to screen the general population for the risk of developing mental health problems. Additionally, the advent of machine learning techniques represents an exciting way to potentially improve upon the standard prediction modelling technique, logistic regression. Therefore, we aimed to I.) develop a model that can predict mental health problems in mid-adolescence II.) investigate if machine learning techniques (random forest, support vector machines, neural network, and XGBoost) will outperform logistic regression.

METHODS

In 7,638 twins from the Child and Adolescent Twin Study in Sweden we used 474 predictors derived from parental report and register data. The outcome, mental health problems, was determined by the Strengths and Difficulties Questionnaire. Model performance was determined by the area under the receiver operating characteristic curve (AUC).

RESULTS

Although model performance varied somewhat, the confidence interval overlapped for each model indicating non-significant superiority for the random forest model (AUC = 0.739, 95% CI 0.708-0.769), followed closely by support vector machines (AUC = 0.735, 95% CI 0.707-0.764).

CONCLUSION

Ultimately, our top performing model would not be suitable for clinical use, however it lays important groundwork for future models seeking to predict general mental health outcomes. Future studies should make use of parent-rated assessments when possible. Additionally, it may not be necessary for similar studies to forgo logistic regression in favor of other more complex methods.

ADHD symptoms and their neurodevelopmental correlates in children born very preterm

This study investigated the association between attention-deficit/hyperactivity disorder (ADHD) symptomatology in preschool-aged children who were born very preterm (<33 weeks) and cognitive outcomes, clinical risk and socio-demographic characteristics. 119 very preterm children who participated in the Evaluation of Preterm Imaging Study at term-equivalent age were assessed at a mean age of 4.5 years. Parents completed the ADHD Rating Scale IV, a norm-referenced checklist that evaluates ADHD symptomatology according to diagnostic criteria, and the Behavior Rating Inventory of Executive Function-Preschool version. Children completed the Wechsler Preschool and Primary Scales of Intelligence and the Forward Digit Span task. Longitudinal data including perinatal clinical, qualitative MRI classification, socio-demographic variables and neurodevelopmental disabilities were investigated in relation to ADHD symptomatology. All results were corrected for multiple comparisons using false discovery rate. Results showed that although the proportion of very preterm children with clinically significant ADHD did not differ from normative data after excluding those with neurodevelopmental disabilities, 32.7% met criteria for subthreshold ADHD inattentive type and 33.6% for combined type, which was higher than the expected 20% in normative samples. Higher ADHD symptom scores (all) were associated with greater executive dysfunction (inhibitory self-control, flexibility, and emergent metacognition, corrected p<0.001 for all tests). Higher inattentive ADHD symptom scores were associated with lower IQ (ρ = -0.245, p = 0.011) and higher perinatal clinical risk (more days on mechanical ventilation (ρ = 0.196, p = 0.032) and more days on parenteral nutrition (ρ = 0.222, p = 0.015). Higher hyperactive ADHD symptom scores instead were associated with lower socio-economic status (ρ = 0.259, p = 0.004). These results highlight the importance of monitoring and supporting the development of very preterm children throughout the school years, as subthreshold ADHD symptoms represent risk factors for psychosocial problems and for receiving a future clinical diagnosis of ADHD.

Invited Commentary: The Disillusionment of Developmental Origins of Health and Disease (DOHaD) Epidemiology

The developmental origins of health and disease (DOHaD) model promises a greater understanding of early development but has left unresolved the balance of risks and benefits to offspring of medication use during pregnancy. Masarwa et al. (Am J Epidemiol. 2018;187(8):1817-1827) conducted a meta-analysis of the association between in utero acetaminophen exposure and risks of attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). A challenge of meta-analyzing results from observational studies is that summary measures of risk do not correspond to well-defined interventions when the individual studies adjusted for different covariate sets, which was the case here. This challenge limits the usefulness of observational meta-analyses for inferences about etiology and treatment planning. With that limitation understood, Masarwa et al. reported a 20%-30% higher risk of ADHD and ASD following prenatal acetaminophen exposure. Surprisingly, most of the original studies did not report diagnoses of ADHD or ASD. As a result, their summary estimates of risk are not informative about children's likelihood of ADHD and ASD diagnoses. The long-term promise of DOHaD remains hopeful, but more effort is needed in the short-term to critically evaluate observational studies suggesting risks associated with medications used to treat conditions during pregnancy that might have adverse consequences for a developing fetus.

The clinical relevance of asking young psychiatric patients about childhood ADHD symptoms

Aim: The aim of this study was to explore the relevance of asking young psychiatric patients about childhood symptoms of attention deficit hyperactivity disorder (ADHD).Method: A total of 180 young adults (18-25 years of age) from a general psychiatric out-patient clinic in Uppsala filled in the Child and Adolescent Psychiatric Screening Inventory-Retrospect (CAPSI-R) as part of the diagnostic procedure. The study population was divided into groups based on number and subtype of reported ADHD symptoms, inattention (IN) or hyperactivity/impulsivity (HI). The clinical characteristics associated with different symptoms of ADHD were explored.Results: The groups with five or more self-reported ADHD childhood symptoms, of either IN or HI, had more psychiatric comorbid conditions, a significantly higher co-occurrence of substance use disorders and personality disorders, and experienced more psychosocial and environmental problems.Conclusion: High level of self-reported ADHD childhood symptoms in young psychiatric patients identified a group more burdened with psychiatric comorbid conditions and more psychosocial problems. This group should be offered a thorough diagnostic assessment of ADHD.

Cost-effectiveness analysis of parenting interventions for the prevention of behaviour problems in children

BACKGROUND

Behavior problems are common among children and place a high disease and financial burden on individuals and society. Parenting interventions are commonly used to prevent such problems, but little is known about their possible longer-term economic benefits. This study modelled the longer-term cost-effectiveness of five parenting interventions delivered in a Swedish context: Comet, Connect, the Incredible Years (IY), COPE, bibliotherapy, and a waitlist control, for the prevention of persistent behavior problems.

METHODS

A decision analytic model was developed and used to forecast the cost per averted disability-adjusted life-year (DALY) by each parenting intervention and the waitlist control, for children aged 5-12 years. Age-specific cohorts were modelled until the age of 18. Educational and health care sector costs related to behavior problems were included. Active interventions were compared to the waitlist control as well as to each other.

RESULTS

Intervention costs ranged between US$ 14 (bibliotherapy) to US$ 1,300 (IY) per child, with effects of up to 0.23 averted DALYs per child (IY). All parenting interventions were cost-effective at a threshold of US$ 15,000 per DALY in relation to the waitlist control. COPE and bibliotherapy strongly dominated the other options, and an additional US$ 2,629 would have to be invested in COPE to avert one extra DALY, in comparison to bibliotherapy.

CONCLUSIONS

Parenting interventions are cost-effective in the longer run in comparison to a waitlist control. Bibliotherapy or COPE are the most efficient options when comparing interventions to one another. Optimal decision for investment should to be based on budget considerations and priority settings.

Mouse movement measures enhance the stop-signal task in adult ADHD assessment

The accurate detection of attention-deficit/hyperactivity disorder (ADHD) symptoms, such as inattentiveness and behavioral disinhibition, is crucial for delivering timely assistance and treatment. ADHD is commonly diagnosed and studied with specialized questionnaires and behavioral tests such as the stop-signal task. However, in cases of late-onset or mild forms of ADHD, behavioral measures often fail to gauge the deficiencies well-highlighted by questionnaires. To improve the sensitivity of behavioral tests, we propose a novel version of the stop-signal task (SST), which integrates mouse cursor tracking. In two studies, we investigated whether introducing mouse movement measures to the stop-signal task improves associations with questionnaire-based measures, as compared to the traditional (keypress-based) version of SST. We also scrutinized the influence of different parameters of stop-signal tasks, such as the method of stop-signal delay setting or definition of response inhibition failure, on these associations. Our results show that a) SSRT has weak association with impulsivity, while mouse movement measures have strong and significant association with impulsivity; b) machine learning models trained on the mouse movement data from "known" participants using nested cross-validation procedure can accurately predict impulsivity ratings of "unknown" participants; c) mouse movement features such as maximum acceleration and maximum velocity are among the most important predictors for impulsivity; d) using preset stop-signal delays prompts behavior that is more indicative of impulsivity.

ADHD and subthreshold symptoms in childhood and life outcomes at 40 years in a prospective birth-risk cohort

We investigated ADHD symptoms and life outcomes in adulthood and their association with childhood ADHD and subthreshold symptoms in a prospectively followed cohort with perinatal risks. We identified participants with childhood ADHD (cADHD, n = 37), subthreshold symptoms defined as attention problems (cAP, n = 64), and no ADHD or cAP (Non-cAP, n = 217). We compared the groups and a control group with no perinatal risks (n = 64) on self-reported ADHD symptoms, executive dysfunction, and life outcomes in adulthood. At age 40, 21.6% of the cADHD, 6.3% of the cAP, 6.0% of the Non-cAP group, and 1.6% of the controls reached a screener cutoff for possible ADHD. The cADHD group had lower educational level, more ADHD symptoms and executive dysfunction, and higher rates of drug use than the other groups. Childhood ADHD associated with perinatal risks persists into midlife whereas childhood subthreshold ADHD symptoms in this cohort were not associated with negative outcomes in adulthood.

Risk of Alcohol Abuse in Humans with Attention-deficit/Hyperactivity Disorder Symptoms

The relationship between attention-deficit/hyperactivity disorder (ADHD) and the risk of alcohol abuse is widely studied. Even though this topic has been of interest for several years, it is heavily debated. We studied various papers and conducted a systematic review using PubMed as the main source of data collection. We found that several studies put forward the concept of a positive association between alcohol abuse and ADHD symptoms, but a minority of them also showed opposing and contradictory results. We discovered that this inconsistency observed in studies could be a result of a biased approach in studies and a subjective attempt in interpretations. These biases could be studied in terms of sample size involved in the analysis, age at which studies are conducted among other statistical parameters. We believe that the deviations in the outcomes prove that the studies may be incomplete and that a standardized method of interpretation is required. Therefore, this paper recommends the need for further research to explore the connection between alcohol abuse in patients showing ADHD symptoms.

Prevalence, comorbidity, functioning and long-term effects of subthreshold oppositional defiant disorder in a community sample of preschoolers

To study the prevalence of subthreshold oppositional defiant disorder (ST ODD)-less than 4 symptoms, but nonetheless an impairing form of oppositional defiant disorder (ODD)-its coexistence with other homotypic externalizing and heterotypical internalizing problems in children and associated impairment, as well as the long-term effect of this condition. A population-based sample of 622 preschoolers (5.0% boys) was followed up from preschool to preadolescence. Parents were interviewed when the children were 3, 6 and 9 years old with the Diagnostic Interview for Preschoolers/Children and Adolescents versions following DSM-5 and the children's functioning was assessed by trained clinicians. ST ODD diagnosis is highly prevalent (19.4-25.5%), highly comorbid [homo- (1.9-18.4%) and heterotypical (5.8-23.7%)], resulting in functional impairment across child development in a similar way for both genders. ST is also a risk factor condition that predicts the presence of psychological problems and impairment in childhood and preadolescence from preschool age. A broader clinical assessment and intervention similar to that provided full syndrome cases is needed for children presenting subthreshold forms of ODD.

Retrospective parental assessment of childhood neurodevelopmental problems: the use of the Five to Fifteen questionnaire in adults

BACKGROUND

Attention-deficit hyperactivity disorder and autism are increasingly recognised in adults. For a diagnostic evaluation, parental information on childhood development is needed. However, no instruments that retrospectively describe neurodevelopmental problems in childhood are validated for evaluating adults. The 181-item parent-report questionnaire Five to Fifteen (FTF) is nevertheless frequently used for assessments in adulthood.

AIMS

To examine if FTF is reliable for obtaining retrospective neurodevelopmental history among young adults.

METHOD

Details of parents who had assessed their children with the FTF for neuropsychiatric evaluation were retrieved and they were asked to complete the FTF again 10-19 years later. Agreements between original and retrospective scorings were analysed.

RESULTS

Long-term reliability for FTF varies considerably between individual items. Several difficulties are reported as more severe at the retrospective scoring than at the original scoring. A selection of 24 items (FTF-Brief) with good agreement over time, is presented for use in adult psychiatry settings.

CONCLUSION

Neuropsychiatric symptoms may fluctuate over time and become more prominent when demands increase. Informants' recollections of their child's neurodevelopmental symptoms may be a selection of symptoms that are longstanding rather than present at a specific age in childhood.

DECLARATION OF INTEREST

None.

Are subsyndromal manifestations of attention deficit hyperactivity disorder morbid in children? A systematic qualitative review of the literature with meta-analysis

We conducted a qualitative review (n = 15 manuscripts) and meta-analysis (n = 9 manuscripts) of the extant literature to evaluate the prevalence and morbidity of subthreshold Attention Deficit Hyperactivity Disorder (ADHD). Our qualitative review showed that a sizable minority (mean: 17.7%) of clinically referred and non-referred children met a priori definitions of subthreshold ADHD. Those affected exhibited significantly higher rates of family dysfunction, cognitive impairment, executive dysfunction, interpersonal and school deficits, temperament problems, psychiatric comorbidity, and juvenile delinquency compared to children with no ADHD symptoms. These deficits were highly consistent with those observed in children with full threshold ADHD. These findings indicate that children with subthreshold ADHD symptoms are at significantly greater risk for negative outcomes in a wide range of non-overlapping functional domains worthy of further clinical and scientific consideration.

Effect Modification by Attention Deficit Hyperactivity Disorder (ADHD) Symptoms on the Association of Psychosocial Work Environments With Psychological Distress and Work Engagement

Objective: The aim of this study was to examine how attention-deficit hyperactivity disorder (ADHD) symptoms play an interaction effect on the association between psychosocial work environments and health (psychological distress/work engagement) among workers. Methods: This is a cross-sectional study of 2,693 employees at a pharmaceutical company using a self-administered questionnaire evaluating ADHD symptoms (Adult ADHD Self-Report Scale Screener), psychosocial work environments (job demands, job control and social support), and health outcomes (psychological distress; K6, and work engagement; Utrecht Work Engagement Scale). Multiple regression analyses were applied to assess the interaction between ADHD symptoms and psychosocial work environments on health outcomes. Results: The prevalence of workers with ADHD symptoms was 5.9% (n = 159). Significant interaction effects of ADHD symptoms × job control and ADHD symptoms × social support were observed (β = -0.067, p < 0.01 and β = -0.052, p < 0.01, respectively) on psychological distress after adjustment of age, sex, occupation and education. The interaction effect of ADHD symptoms × each psychosocial work environment was not observed on work engagement. Conclusions: Job control and social support were more influential factors that were related to psychological distress in accordance with ADHD symptoms. This study also found no difference of the interaction between psychosocial work environments and ADHD symptoms on work engagement. To the best of our knowledge, this study was first to clarify the effect of ADHD symptoms on the association between psychosocial work environments and health outcomes (psychological distress/work engagement). These findings can aid employers how to arrange better work environments for workers with ADHD symptoms.

Augmented Go/No-Go Task: Mouse Cursor Motion Measures Improve ADHD Symptom Assessment in Healthy College Students

Attention deficit/hyperactivity disorder (ADHD) is frequently characterized as a disorder of executive function (EF). However, behavioral tests of EF, such as go/No-go tasks, often fail to grasp the deficiency in EF revealed by questionnaire-based measures. This inability is usually attributed to questionnaires and behavioral tasks assessing different constructs of EFs. We propose an additional explanation for this discrepancy. We hypothesize that this problem stems from the lack of dynamic assessment of decision-making (e.g., continuous monitoring of motor behavior such as velocity and acceleration in choice reaching) in classical versions of behavioral tasks. We test this hypothesis by introducing dynamic assessment in the form of mouse motion in a go/No-go task. Our results indicate that, among healthy college students, self-report measures of ADHD symptoms become strongly associated with performance in behavioral tasks when continuous assessment (e.g., acceleration in the mouse-cursor motion) is introduced.

Associations between childhood ADHD, gender, and adolescent alcohol and marijuana involvement: A causally informative design

BACKGROUND

We report whether the etiology underlying associations of childhood ADHD with adolescent alcohol and marijuana involvement is consistent with causal relationships or shared predispositions, and whether it differs by gender.

METHODS

In three population-based twin samples (N = 3762; 64% monozygotic), including one oversampling females with ADHD, regressions were conducted with childhood inattentive or hyperactive-impulsive symptoms predicting alcohol and marijuana outcomes by age 17. To determine whether ADHD effects were consistent with causality, twin difference analyses divided effects into those shared between twins in the pair and those differing within pairs.

RESULTS

Adolescents with more severe childhood ADHD were more likely to initiate alcohol and marijuana use earlier, escalate to frequent or heavy use, and develop symptoms. While risks were similar across genders, females with more hyperactivity-impulsivity had higher alcohol consumption and progressed further toward daily marijuana use than did males. Monozygotic twins with more severe ADHD than their co-twins did not differ significantly on alcohol or marijuana outcomes, however, suggesting a non-causal relationship. When co-occurring use of other substances and conduct/oppositional defiant disorders were considered, hyperactivity-impulsivity remained significantly associated with both substances, as did inattention with marijuana, but not alcohol.

CONCLUSIONS

Childhood ADHD predicts when alcohol and marijuana use are initiated and how quickly use escalates. Shared familial environment and genetics, rather than causal influences, primarily account for these associations. Stronger relationships between hyperactivity-impulsivity and heavy drinking/frequent marijuana use among adolescent females than males, as well as the greater salience of inattention for marijuana, merit further investigation.

Efficacy and safety of ginkgo preparations for attention deficit hyperactivity disorder: a systematic review protocol

INTRODUCTION

Attention deficit hyperactivity disorder (ADHD) is one of the most commonly diagnosed and treated childhood psychiatric disorders. The analogous diagnosis adopted in Europe is hyperkinetic disorder, which is defined in the WHO's International Classification of Diseases 10th edition (ICD-10). Hyperkinetic disorder includes more severe conditions. Ginkgo preparations are used in the treatment of ADHD. The present study will assess the efficacy and safety of ginkgo preparations in the treatment of ADHD in the currently published literature.

MATERIALS AND METHODS

All prospective randomised controlled trials (RCTs) will be included in this systematic review. Patients diagnosed with ADHD according to American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders fourth edition (DSM-IV), Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5), ICD-10 or Chinese Classification and Diagnosis of Mental Diseases third edition (CMDD) will be included. A comprehensive search for RCTs to evaluate the effectiveness and tolerance of ginkgo preparations will be performed. The primary outcomes are the ADHD Rating Scale-IV and Revised Conners' Parent Rating Scale. The secondary outcomes are quality of life evaluated by the KINDL scale, adverse effects/events, Conners' Teacher Rating Scale, Strengths and Weaknesses of ADHD Symptoms and Normal Behaviour Scale and Fremdbeurteilungsbogen für Hyperkinetische Störungen. Exclusion criteria are the following: (1) case reports, not randomised trial, non-comparative studies and (2) patients who were not diagnosed based on DSM-IV, DSM-5, ICD-10 or CMDD. The following databases will be searched from their inception until January 2018: Medline, Embase, the Cochrane Central Register of Controlled Trials, Web of Science, China Biology Medicine Disc, China National Knowledge Infrastructure Database, Wanfang Database and Chinese Scientific Journals Database. Two authors will independently perform the study selection, extract the data and assess the study quality and risk of bias.

ETHICS AND DISSEMINATION

This systematic review does not require ethics approval. It will be published in a peer-reviewed journal.

PROSPERO REGISTRATION NUMBER

CRD42017077190.

One-year abstinence improves ADHD symptoms among patients with polysubstance use disorder

INTRODUCTION

Attention-deficit/hyperactivity disorder (ADHD) is a common comorbid disorder in patients suffering from substance use disorder (SUD). Individuals with co-occurring SUD and ADHD are more likely than SUD patients without ADHD to have developed SUD at a younger age, be polysubstance users, and need inpatient treatment more often. The present study investigates whether individuals with polysubstance use disorder who remain abstinent for a year after entering treatment have a more substantial reduction in ADHD symptoms than those who relapsed and controls.

MATERIAL AND METHODS

Subjects were SUD patients (N = 115) and healthy controls (N = 34). ADHD symptoms were assessed using the adult ADHD Self-Report Scale (ASRS). Substance use was assessed by self-reports on the Alcohol Use Disorders Identification Test (AUDIT) and the Drug Use Disorders Identification Test (DUDIT). Participants were defined as having relapsed if they had an AUDIT score ≥ 8 or a DUDIT score ≥ 2 for women and ≥ 6 for men.

RESULTS

Patients who remained abstinent for one year reported a substantial reduction of ADHD symptoms compared to patients who relapsed and controls.

CONCLUSIONS

Abstinence alleviates ADHD symptoms among patients with polysubstance use disorder. We suggest that confirmation of an ADHD diagnosis should follow a period of abstinence to avoid identification of false-positive cases.

Subthreshold and threshold attention deficit hyperactivity disorder symptoms in childhood: psychosocial outcomes in adolescence in boys and girls

OBJECTIVE

To examine the association between different levels of childhood attention deficit hyperactivity disorder (ADHD) symptoms and sex differences in psychosocial outcomes during adolescence.

METHOD

Swedish children (n = 4635) were screened for neuropsychiatric symptoms at age 9 or 12. ADHD symptoms were divided into three levels: screen-negative, screen-intermediate, and screen-positive. At follow-up (age 15), parents and teenagers filled out questionnaires regarding (i) hyperactivity/inattention, (ii) peer problems, (iii) school problems, (iv) internalizing problems, (v) antisocial behaviour, (vi) alcohol misuse, and (vii) drug misuse. All outcomes were controlled for symptoms of diagnostic categories other than ADHD.

RESULTS

Increasing levels of ADHD symptoms in childhood were associated with higher proportions of adolescents who displayed negative psychosocial outcomes. More girls than boys reported internalizing problems (all levels) and risky drug use (screen-intermediate and screen-positive only). More boys reported antisocial behaviour at the screen-negative and screen-intermediate levels, but at the screen-positive level, similar proportions of girls and boys displayed antisocial behaviour.

CONCLUSION

The findings support the view that ADHD symptoms, as well as their negative outcomes, are dimensionally distributed in the population and that adolescent girls and boys display different risk profiles. The findings confirm that ADHD symptoms are associated with higher risk of drug misuse in girls.