Randomized controlled double-blind trial of optimal dose methylphenidate in children and adolescents with severe attention deficit hyperactivity disorder and intellectual disability.

BACKGROUND: Attention deficit hyperactivity disorder is increased in children with intellectual disability. Previous research has suggested stimulants are less effective than in typically developing children but no studies have titrated medication for individual optimal dosing or tested the effects for longer than 4 weeks. METHOD: One hundred and twenty two drug-free children aged 7-15 with hyperkinetic disorder and IQ 30-69 were recruited to a double-blind, placebo-controlled trial that randomized participants using minimization by probability, stratified by referral source and IQ level in a one to one ratio. Methylphenidate was compared with placebo. Dose titration comprised at least 1 week each of low (0.5 mg/kg/day), medium (1.0 mg/kg/day) and high dose (1.5 mg/kg/day). Parent and teacher Attention deficit hyperactivity disorder (ADHD) index of the Conners Rating Scale-Short Version at 16 weeks provided the primary outcome measures. Clinical response was determined with the Clinical Global Impressions scale (CGI-I). Adverse effects were evaluated by a parent-rated questionnaire, weight, pulse and blood pressure. Analyses were by intention to treat. TRIAL REGISTRATION: ISRCTN 68384912. RESULTS: Methylphenidate was superior to placebo with effect sizes of 0.39 [95% confidence intervals (CIs) 0.09, 0.70] and 0.52 (95% CIs 0.23, 0.82) for the parent and teacher Conners ADHD index. Four (7%) children on placebo versus 24 (40%) of those on methylphenidate were judged improved or much improved on the CGI. IQ and autistic symptoms did not affect treatment efficacy. Active medication was associated with sleep difficulty, loss of appetite and weight loss but there were no significant differences in pulse or blood pressure. CONCLUSIONS: Optimal dosing of methylphenidate is practical and effective in some children with hyperkinetic disorder and intellectual disability. Adverse effects typical of methylphenidate were seen and medication use may require close monitoring in this vulnerable group.

Adolescent emotional and behavioural outcomes of nonparental preschool childcare.

PURPOSE: This study aimed to identify whether nonparental preschool childcare was associated with adolescent mental health outcomes as measured by the strengths and difficulties questionnaire (SDQ). METHOD: This study was a secondary analysis of data from the Croydon Assessment of Learning Study. From a general population sample of 2,726 adolescents tested for cognitive ability, additional data were collected from a stratified sub-sample of 197 subjects. A semi-structured interview asked parents about preschool childcare and early development concerns. Parent and teacher SDQ and IQ data were collected. Complete data were available from 167 subjects. Using nonparental preschool childcare as the 'treatment' effect and parental childcare as the 'control', propensity score matching analyses were used to analyse the effect of nonparental childcare on adolescent SDQ outcomes. RESULTS: Nonparental childcare was reported by 49% of the sample and was not significantly associated with conduct, emotional, peer or prosocial SDQ subscales, but was found to have a significant average treatment effect on symptoms of attention/hyperactivity, on average raising the symptom subscale score by 1.8 (95% confidence interval 0.12-3.65). The propensity score analysis ensures the results could not be explained by the available measures that influenced receiving nonparental care. Increased time spent in nonparental childcare was associated with greater attention/hyperactivity symptoms. CONCLUSIONS: Nonparental preschool care showed little association with generalized psychopathology but may be associated with hyperactivity and inattention problems. Replication of these findings in prospective studies is required.

Eye Movements and Behavioural Responses to Gaze-Contingent Expressive Faces in Typically Developing Infants and Infant Siblings.

Studies with infant siblings of children with Autism Spectrum Disorder have attempted to identify early markers for the disorder and suggest that autistic symptoms emerge between 12 and 24 months of age. Yet, a reliable first-year marker remains elusive. We propose that in order to establish first-year manifestations of this inherently social disorder, we need to develop research methods that are sufficiently socially demanding and realistically interactive. Building on Keemink et al. [2019, Developmental Psychology, 55, 1362-1371], we employed a gaze-contingent eye-tracking paradigm in which infants could interact with face stimuli. Infants could elicit emotional expressions (happiness, sadness, surprise, fear, disgust, anger) from on-screen faces by engaging in eye contact. We collected eye-tracking data and video-recorded behavioural response data from 122 (64 male, 58 female) typically developing infants and 31 infant siblings (17 male, 14 female) aged 6-, 9- and 12-months old. All infants demonstrated a significant Expression by AOI interaction (F(10, 1470) = 10.003, P < 0.001, ŋp2  = 0.064). Infants' eye movements were "expression-specific" with infants distributing their fixations to AOIs differently per expression. Whereas eye movements provide no evidence of deviancies, behavioural response data show significant aberrancies in reciprocity for infant siblings. Infant siblings show reduced social responsiveness at the group level (F(1, 147) = 4.10, P = 0.042, ŋp2  = 0.028) and individual level (Fischer's Exact, P = 0.032). We conclude that the gaze-contingency paradigm provides a realistically interactive experience capable of detecting deviancies in social responsiveness early, and we discuss our results in relation to subsequent infant sibling development. LAY SUMMARY: We investigated how infant siblings of children with autism spectrum disorder respond to interactive faces presented on a computer screen. Our study demonstrates that infant siblings are less responsive when interacting with faces on a computer screen (e.g., they smile and imitate less) in comparison to infants without an older sibling with autism. Reduced responsiveness within social interaction could potentially have implications for how parents and carers interact with these infants. Autism Res 2021, 14: 973-983. © 2020 International Society for Autism Research and Wiley Periodicals LLC.

ADHD symptoms in children with mild intellectual disability.

OBJECTIVES: To determine whether the nature and correlates of attention-deficit/hyperactivity disorder (ADHD) symptoms are different in subjects with mild intellectual disability (ID) compared to subjects with average ability. METHOD: From a general population sample of 2,726 12- to 15-year-olds, a stratified subsample was selected to enrich for mild ID. A total of 192 subjects were included in the analyses. ADHD symptoms and other emotional/behavioral problems were measured with the parent and teacher Strengths and Difficulties Questionnaire and IQ with the WISC-III-UK), and social communication difficulties were assessed by a short version of the Social Communication Questionnaire and academic attainments by the Wechsler Quicktest. RESULTS: There was a negative linear relationship between ADHD symptoms and IQ (beta = -.087, p <.001). The relationship could not be explained by inappropriate rater expectations. Neither the profiles of ADHD symptoms nor the comorbidity with emotional/behavioral problems differed according to the presence of ID. When IQ was accounted for, the group difference in attainments was nonsignificant. CONCLUSIONS: ADHD symptoms are increased in people with ID. We found no evidence that this increase can by explained by inappropriate expectations or by confounding associations with other emotional/behavioral or cognitive problems.

The Croydon Assessment of Learning Study: prevalence and educational identification of mild mental retardation.

BACKGROUND: Mild mental retardation is an enduring and impairing condition. Its prevalence has varied widely across different studies from .5 to over 8%, with higher rates in completely ascertained samples. The current study estimates the prevalence of low IQ in the mental retardation range (intellectual disability) in a population sample and examines the factors that relate to educational identification. METHOD: A total of 2,730 children in school years 8 and 9 attending local authority schools were assessed in school with the group-administered Cognitive Abilities Test (CAT). A sample of 304 pupils at high, moderate and low risk of mild mental retardation was selected for in-depth study. This included the individually measured full-scale IQ (WISC-III(UK)), the Wechsler Quicktest of attainments, the Strengths and Difficulties Questionnaire from parents and teachers and an abbreviated version of the Social Communication Questionnaire. RESULTS: Of those selected for the in-depth study, 204 (67%) participated, with a greater proportion from the low risk group. A range of prevalence estimates were calculated using different imputation methods and assumptions about individuals not screened. Rates of pupils with WISC IQ < 70 varied from 5.8% to 10.6%. There were no significant gender differences. In contrast to the high prevalence estimates using the WISC, the proportion of pupils scoring in the lowest stanine on the CAT was as expected. Only 15% of those with IQ < 70 had a statement of special educational needs or attended a school for moderate learning difficulties. Behaviour, particularly social communication problems, predicted educational identification. CONCLUSIONS: The current study produced a high estimate of the prevalence of mild intellectual disability based on the WISC but not on the CAT. The findings highlight that the majority of mild intellectual disability in the UK would not be detected using registers. Cases that are detected by registers are more behaviourally disturbed than others.