Maj-Britt Posserud

Sleep problems in children with autism spectrum problems: a longitudinal population-based study:

This study examined the prevalence and chronicity of sleep problems in children who manifest problems believed to be typical of Autism Spectrum Disorders (ASD). Using data from a longitudinal total population study, symptoms of ASD, insomnia and potential explanatory factors were assessed at ages 7–9 and 11–13. Children were included in a group defined as having Autism Spectrum Problems (ASP) if they scored above a strict threshold on the Autism Spectrum Screening Questionnaire (ASSQ). Twenty-eight (0.8%) of 3700 children fulfilled the selected criteria for ASP at both waves, and the prevalence of chronic insomnia was more than ten times higher in these children compared to the controls. Children with ASP developed more sleep problems over time, with an incidence rate at wave 2 of 37.5% compared to 8.6% in the controls. The sleep problems were more persistent over time, with a remission rate of 8.3% compared to 52.4% in the controls. ASP was a strong predictor of sleep problems at wave 2 (OR = 12.44), and while emotional and behavioural problems explained a large proportion of this association, the effect of ASP on insomnia remained significant in the fully adjusted model (OR = 3.25). These findings call for increased awareness of sleep problems in children with ASP.

Symptoms of depression as reported by Norwegian adolescents on the Short Mood and Feelings Questionnaire

The present study investigated sex-differences in reports of depressive symptoms on a Norwegian translation of the short version of the Mood and Feelings Questionnaire (SMFQ). The sample comprised 9702 Norwegian adolescents (born 1993–1995, 54.9% girls), mainly attending highschool. A set of statistical analyses were run to investigate the dimensionality of the SMFQ. Girls scored significantly higher than boys on the SMFQ and used the most severe response-category far more frequently. Overall, the statistical analyses supported the essential unidimensionality of SMFQ. However, the items with the highest loadings according to the bifactor analysis, reflecting problems related to tiredness, restlessness and concentration difficulties, indicated that some of the symptoms may both be independent of and part of the symptomatology of depression. Measurement invariance analysis showed that girls scored slightly higher on some items when taking the latent variable into account; girls had a lower threshold for reporting mood problems and problems related to tiredness than boys, who showed a marginally lower threshold for reporting that no-one loved them. However, the effect on the total SMFQ score was marginal, supporting the use of the Norwegian translation of SMFQ as a continuous variable in further studies of adolescents.

The Factor Structure of ADHD in a General Population of Primary School Children.

OBJECTIVE To examine whether a bifactor model with a general ADHD factor and domain specific factors of inattention, hyperactivity and impulsivity was supported in a large general population sample of children. We also explored the utility of forming subscales based on the domain-specific factors. METHODS Child mental health questionnaires were completed by both teachers and parents of all children in grades 2-4 in Bergen, Norway. Confirmatory factor analysis was performed on the ADHD items of a modified version of the Swanson, Nolan and Pelham Questionnaire-IV (SNAP-IV) for 6,237 children. RESULTS The bifactor model showed very good model fit with a strong general ADHD factor and specific factors for impulsivity and inattention. The subfactors, especially hyperactivity, generated from the SNAP-IV ADHD items conveyed little unique variance in the model. CONCLUSIONS The findings in this general population sample with a strong general ADHD factor in the bifactor model supports the view on ADHD as a unitary concept with specific domain factors for inattention and impulsivity, but not for hyperactivity. The bifactor model questions the utility of constructing ADHD subscales by the use of a simple sum score when using the SNAP-IV.

Stable associations between behavioral problems and language impairments across childhood – The importance of pragmatic language problems

This study investigated language function associated with behavior problems, focusing on pragmatics. Scores on the Childrens Communication Checklist Second Edition (CCC-2) in a group of 40 adolescents (12-15 years) identified with externalizing behavior problems (BP) in childhood was compared to the CCC-2 scores in a typically developing comparison group (n=37). Behavioral, emotional and language problems were assessed by the Strengths and Difficulties Questionnaire (SDQ) and 4 language items, when the children in the BP group were 7-9 years (T1). They were then assessed with the SDQ and the CCC-2 when they were 12-15 years (T2). The BP group obtained poorer scores on 9/10 subscales on the CCC-2, and 70% showed language impairments in the clinical range. Language, emotional and peer problems at T1 were strongly correlated with pragmatic language impairments in adolescence. The findings indicate that assessment of language, especially pragmatics, is vital for follow-up and treatment of behavioral problems in children and adolescents.

Attention Deficits in Children With Combined Autism and ADHD: A CPT Study

Objective: To investigate characteristics of attention in children with the combination of autism spectrum disorder (ASD) and ADHD. Method: Four groups of 8- to 10-year-old children were compared on the Conners’ Continuous Performance Test–Second Edition (CCPT-II): (a) ASD + ADHD (n = 11), (b) ASD only (n = 9), (c) ADHD only (n = 38), and (d) no diagnosis (n = 134). Results: There was an overall effect of group on the Continuous Performance Test (CPT) index and measures of hit reaction time, accuracy, response style, variability, and consistency. The ASD + ADHD group, much like the ADHD only group, had a more risky response style, a higher variability, and a lower consistency than the ASD only group. The impact of intellectual function on CCPT-II performance was considerable in children within the ASD subgroups. Conclusion: The findings underscore the importance of including measures of attention and intellectual function when assessing children with the combination of ASD and ADHD.

Brain MR spectroscopy in autism spectrum disorder—the GABA excitatory/inhibitory imbalance theory revisited

Magnetic resonance spectroscopy (MRS) from voxels placed in the left anterior cingulate cortex (ACC) was measured from 14 boys with Autism Spectrum Disorder (ASD) and 24 gender and age-matched typically developing (TD) control group. Our main aims were to compare the concentration of γ-aminobutyric acid (GABA) between the two groups, and to investigate the relationship between brain metabolites and autism symptom severity in the ASD group. We did find a significant negative correlation in the ASD group between Autism Spectrum Screening Questionnaire (ASSQ) and GABA+/Cr, which may imply that severity of symptoms in ASD is associated with differences in the level of GABA in the brain, supporting the excitatory/inhibitory (E/I) imbalance theory. However we did not find a significant difference between the two groups in GABA levels.

Association Between Sleep Problems and Symptoms of Attention Deficit Hyperactivity Disorder in Adolescence: Results From a Large Population-Based Study

Sleep problems and symptoms of ADHD are common in adolescence, but detailed epidemiological assessment of their association is lacking. Using data from a recent population-based study, 9,846 adolescents aged 16 to 19 provided detailed information on sleep and symptoms of ADHD. Results confirmed a large overlap between self-reported symptoms of ADHD and all sleep variables studied. Symptoms of ADHD were linked to shorter sleep duration, longer sleep latency, and nocturnal wake time, as well as larger sleep deficiency. ADHD symptoms also increased the odds of insomnia and delayed sleep phase syndrome. The associations were only partially explained by confounders (mainly depression). The findings suggest that sleep problems should be included as a treatment target in efforts to reduce symptoms of ADHD in adolescence.

Autism spectrum symptoms in children with neurological disorders

BackgroundThe aims of the present study were to assess symptoms associated with an autism spectrum disorder (ASD) in children with neurological disorders as reported by parents and teachers on the Autism Spectrum Screening Questionnaire (ASSQ), as well as the level of agreement between informants for each child.MethodsThe ASSQ was completed by parents and teachers of the 5781 children (11–13 years) who participated in the second wave of the Bergen Child Study (BCS), an on-going longitudinal population-based study. Out of these children, 496 were reported to have a chronic illness, including 99 whom had a neurological disorder. The neurological disorder group included children both with and without intellectual disabilities.ResultsChildren with neurological disorders obtained significantly higher parent and teacher reported ASSQ scores than did non-chronically ill children and those with other chronic illnesses (p<.01; ES = .50-1.01), and 14.1% were screened above the positive cutoff score for ASD according to their combined parent and teacher ASSQ scores. Parent/teacher agreement over ASSQ scores for children with neurological disorders was moderate to high for the total score and for three sub scores generated from a factor analysis, and low to moderate for single items.ConclusionsThe ASSQ identifies a high rate of ASD symptoms in children with neurological disorders, and a large number of children screened in the positive range for ASD. Although a firm conclusion awaits further clinical studies, the present results suggest that health care professionals should be aware of potential ASD related problems in children with neurological disorders, and should consider inclusion of the ASSQ or similar screening instruments as part of their routine assessment of this group of children.

Language Impairments in Children With ADHD and in Children With Reading Disorder

Objective: The objective of this study was to investigate language impairments (LI) in a nonclinical sample of children with ADHD, reading disorder (RD), and ADHD + RD, and to explore whether these groups could be differentiated from each other and a control group regarding different aspects of language. Method: The groups were derived from a population-based sample of 5,672 children, 7 to 9 years. Language problems and the groups were defined from parent/teacher reports. Results: LI was identified in the majority within the ADHD + RD group and in >40% of the ADHD and RD group. More phonological and expressive language problems were seen in the RD than the ADHD group, while receptive language problems were more prominent in ADHD. More pragmatic problems were identified in the ADHD group. Conclusion: The present results support findings from clinical samples pointing to a considerable rate of LI both in children with ADHD and in children with RD.

Genome-wide analyses of aggressiveness in attention-deficit hyperactivity disorder

Aggressiveness is a behavioral trait that has the potential to be harmful to individuals and society. With an estimated heritability of about 40%, genetics is important in its development. We performed an exploratory genome‐wide association (GWA) analysis of childhood aggressiveness in attention deficit hyperactivity disorder (ADHD) to gain insight into the underlying biological processes associated with this trait. Our primary sample consisted of 1,060 adult ADHD patients (aADHD). To further explore the genetic architecture of childhood aggressiveness, we performed enrichment analyses of suggestive genome‐wide associations observed in aADHD among GWA signals of dimensions of oppositionality (defiant/vindictive and irritable dimensions) in childhood ADHD (cADHD). No single polymorphism reached genome‐wide significance (P < 5.00E‐08). The strongest signal in aADHD was observed at rs10826548, within a long noncoding RNA gene (beta = −1.66, standard error (SE) = 0.34, P = 1.07E‐06), closely followed by rs35974940 in the neurotrimin gene (beta = 3.23, SE = 0.67, P = 1.26E‐06). The top GWA SNPs observed in aADHD showed significant enrichment of signals from both the defiant/vindictive dimension (Fishers P‐value = 2.28E‐06) and the irritable dimension in cADHD (Fishers P‐value = 0.0061). In sum, our results identify a number of biologically interesting markers possibly underlying childhood aggressiveness and provide targets for further genetic exploration of aggressiveness across psychiatric disorders.