Apgar Scores Are Associated with Attention-Deficit/Hyperactivity Disorder Symptom Severity.

OBJECTIVE: Adverse events during pregnancy and delivery have been linked to attention-deficit/hyperactivity disorder (ADHD). Previous studies have investigated Apgar scores, which assess the physical condition of newborns, in relation to the risk of developing ADHD. We propose to go one step further and examine if Apgar scores are associated with ADHD symptom severity in children already diagnosed with ADHD. METHOD: ADHD symptoms severity, while off medication, was compared in 2 groups of children with ADHD: those with low (≤6, n = 52) and those with higher (≥7, n = 400) Apgar scores sequentially recruited from the ADHD clinic. RESULTS: Children with low Apgar at 1 minute after birth had more severe symptoms as assessed by the externalizing scale of the Child Behaviour Checklist, the Conners' Global Index for Parents, and the DSM-IV hyperactivity symptoms count (P = 0.02, <0.01, <0.01, respectively). CONCLUSION: Low 1-minute Apgar scores are associated with a significant increase in ADHD symptom severity. These findings underline the importance of appropriate pregnancy and perinatal care.

The Effect of Maternal Stress during Pregnancy on IQ and ADHD Symptomatology.

OBJECTIVE: Maternal stress during pregnancy (MSDP) has been linked to a decrease in Intelligence Quotient (IQ) in the general population. The purpose of this study is to first examine the association between MSDP and IQ in children with Attention-Deficit/Hyperactivity Disorder (ADHD) and second, to confirm, in a large sample, the link between MSDP and ADHD behavioral symptomatology. METHODS: Four hundred ten children diagnosed with ADHD, ages six to 12, were consecutively recruited from the ADHD clinic and day hospital at the Douglas Institute from 1999 to 2013. IQ was assessed using the WISC III and IV. Symptom severity was evaluated using the Child Behavior Checklist (CBCL) and Connor's Global Index for Parents (CGI-P) and Teachers (CGI-T). RESULTS: No significant effect of MSDP on full scale IQ was observed, but MSDP had a significant effect on CBCL and CGI scores. Elevated MSDP was significantly associated with increased CBCL internalizing scores (ß=4.2, p<.01), CBCL externalizing scores (ß=1.9, p=.04), CGI-P restless-impulsive scores (ß=2.6, p=.01), CGI-P emotional lability scores (ß=3.1, p=.02), and CGI-T restless-impulsive (ß=2.2, p=.05) and emotional lability (ß=3.4, p=.04) scores. MSDP increased the variance explained of ADHD symptomatology even after controlling for various factors (i.e. familial income, parental education, smoking and drinking during pregnancy, gender and age). CONCLUSION: The study demonstrates that in children with ADHD, MSDP does not have an impact on IQ but rather on ADHD symptomatology, highlighting the importance of potentially offering psychological and social support to mothers who experience stress during pregnancy.

OBJECTIF: Le stress maternel durant la grossesse (SMDG) a été lié à une diminution du quotient intellectuel (QI) dans la population générale. Cette étude vise d'abord à examiner l'association entre le SMDG et le QI chez les enfants souffrant du trouble de déficit de l'attention avec hyperactivité (TDAH) et deuxièmement, à confirmer, dans un vaste échantillon, le lien entre le SMDG et la symptomatologie comportementale du TDAH. MÉTHODES: Quatre cent dix enfants de 6 à 12 ans ayant reçu un diagnostic de TDAH ont été consécutivement recrutés dans la clinique du TDAH et l'hôpital de jour de l'Institut Douglas, de 1999 à 2013. Le QI a été évalué à l'aide des échelles WISC III et IV. La gravité des symptômes a été évaluée à l'aide de la liste du comportement de l'enfant (CBCL) et de l'index global de Conner pour les parents (CGI-P) et les enseignants (CGI-T). RÉSULTATS: Aucun effet significatif du SMDG sur le QI global n'a été observé, mais le SMDG avait un effet significatif sur les scores à la CBCL et au CGI. Un SMDG élevé était significativement associé à des scores d'internalisation accrus à la CBCL (ß = 4,2; p<0,01), à des scores d'externalisation à la CBCL (ß = 1,9; p = 0,04), à des scores agité-impulsif au CGI-P (ß = 2,6; p = 0,01), à des scores de labilité émotionnelle au CGI-P (ß = 3,1; p = 0,02), et à des scores agité-impulsif (ß = 2,2; p = 0,05) et de labilité émotionnelle au CGI-T (ß = 3,4; p = 0,04). Le SMDG augmentait la variance expliquée de la symptomatologie du TDAH même après contrôle de facteurs variés (c.-à-d., revenu familial, instruction des parents, tabagisme et consommation d'alcool durant la grossesse, sexe et âge). CONCLUSION: L'étude démontre que chez les enfants souffrant du TDAH, le SMDG n'a pas d'incidence sur le QI mais plutôt sur la symptomatologie du TDAH, ce qui souligne l'importance d'offrir potentiellement un soutien psychologique et social aux mères aux prises avec le stress durant la grossesse.

Effects of methylphenidate on acute math performance in children with attention-deficit hyperactivity disorder.

OBJECTIVE: Examine the short-term (acute) effects of methylphenidate (MPH) on math performance in children with attention-deficit hyperactivity disorder (ADHD) and what factors predict improvement in math performance. METHOD: One hundred ninety-eight children with ADHD participated in a double-blind, placebo-controlled, randomized crossover MPH trial. Math response to MPH was determined through administration of math problems adjusted to their academic level during the Restricted Academic Situation Scale (RASS). Student t tests were conducted to assess change in math performance with psychostimulants. Correlation between change on the RASS and change on the math performance was also examined. Linear regression was performed to determine predictor variables. RESULTS: Children with ADHD improved significantly in their math with MPH (P < 0.001). The degree of improvement on the RASS (which evaluates motor activity and orientation to task) and on math performance on MPH was highly correlated. A child's age at baseline and Wechsler Individual Achievement Test (WIAT)-Numerical Operations standard scores at baseline accounted for 15% of variances for acute math improvement. CONCLUSIONS: MPH improves acute math performance in children with ADHD. Younger children with lower math scores (as assessed by the WIAT) improved most on math scores when given psychostimulants. CLINICAL TRIAL REGISTRATION NUMBER: NCT00483106.

Objectif : Examiner les effets à court terme (aigus) du méthylphénidate (MPH) sur la performance en mathématique chez des enfants souffrant du trouble de déficit de l'attention avec hyperactivité (TDAH), et quels facteurs prédisent une amélioration de la performance en math. Méthode : Cent quatre-vingt-dix-huit enfants souffrant du TDAH ont participé à un essai de MPH croisé, randomisé, à double insu et contrôlé avec placebo. La réponse du MPH en math a été déterminée par l'administration de problèmes de math ajustés à leur niveau scolaire durant la Restricted Academic Situation Scale (RASS). Les tests t de Student ont été menés afin d'évaluer le changement de la performance en math avec les psychostimulants. La corrélation entre le changement à la RASS et le changement de la performance en math a aussi été examinée. Une régression linéaire a été exécutée pour déterminer les variables prédictives. Résultats : Les enfants souffrant du TDAH se sont améliorés significativement en math avec le MPH (P < 0,001). Le degré d'amélioration à la RASS (qui évalue l'activité motrice et l'orientation dans les tâches) et dans la performance en math avec MPH était hautement corrélé. L'âge de l'enfant au départ et les scores normaux au départ au Wechsler Individual Achievement Test (WIAT) ­ des opérations numériques représentaient 15 % des variances d'amélioration aiguë en math. Conclusions : Le MPH améliore la performance aiguë en mathématique chez les enfants souffrant du TDAH. Les enfants plus jeunes qui ont de moins bons scores en math (évalué par le WIAT) ont surtout amélioré leurs scores en math lorsqu'ils ont reçu des psychostimulants. Numéro d'enregistrement d'essai clinique : NCT00483106.

Executive functions and methylphenidate response in subtypes of attention-deficit/hyperactivity disorder.

BACKGROUND: Oculomotor tasks are a well-established means of studying executive functions and frontal-striatal functioning in both nonhuman primates and humans. Attention-deficit/hyperactivity disorder (ADHD) is thought to implicate frontal-striatal circuitry. We used oculomotor tests to investigate executive functions and methylphenidate response in two subtypes of ADHD. METHODS: Subjects were boys, aged 11.5-14 years, with ADHD-combined (n = 10), ADHD-inattentive (n = 12), and control subjects (n = 10). Executive functions assessed were motor planning (tapped with predictive saccades), response inhibition (antisaccades), and task switching (saccades-antisaccades mixed). RESULTS: The ADHD-combined boys were impaired relative to control subjects in motor planning (p < .003) and response inhibition (p < .007) but not in task switching (p > .92). They were also significantly impaired relative to ADHD-inattentive boys, making fewer predictive saccades (p < .03) and having more subjects with antisaccade performance in the impaired range (p < .04). Methylphenidate significantly improved motor planning and response inhibition in both subtypes. CONCLUSIONS: ADHD-combined but not ADHD-inattentive boys showed impairments on motor planning and response inhibition. These deficits might be mediated by brain structures implicated specifically in the hyperactive/impulsive symptoms. Methylphenidate improved oculomotor performance in both subtypes; thus, it was effective even when initial performance was not impaired.