Lack of effects of eight-week left dorsolateral prefrontal theta burst stimulation on white matter macro/microstructure and connection in autism

Whether brain stimulation could modulate brain structure in autism remains unknown. This study explored the impact of continuous theta burst stimulation (cTBS) over the left dorsolateral prefrontal cortex (DLPFC) on white matter macro/microstructure in intellectually able children and emerging adults with autism. Sixty autistic participants were randomized (30 active) and received active or sham cTBS for eight weeks twice per week, 16 total sessions using a double-blind (participant-, rater-, analyst-blinded) design. All participants received high-angular resolution diffusion MR imaging at baseline and week 8. Twenty-eight participants in the active group and twenty-seven in the sham group with good imaging quality entered the final analysis. With longitudinal fixel-based analysis and network-based statistics, we found no significant difference between the active and sham groups in changes of white matter macro/microstructure and connections following cTBS. In addition, we found no association between baseline white matter macro/microstructure and autistic symptom changes from baseline to week 8 in the active group. In conclusion, we did not find a significant impact of left DLPFC cTBS on white matter macro/microstructure and connections in children and emerging adults with autism. These findings need to be interpreted in the context that the current intellectually able cohort in a single university hospital site limits the generalizability. Future studies are required to investigate if higher stimulation intensities and/or doses, other personal factors, or rTMS parameters might confer significant brain structural changes visible on MRI in ASD.

Exploring camouflaging by the Chinese version Camouflaging Autistic Traits Questionnaire in Taiwanese autistic and non-autistic adolescents: An initial development

LAY ABSTRACT

Camouflaging is a coping strategy used by some autistic and other neurodivergent people to fit in neurotypical social contexts. The self-reported Camouflaging Autistic Traits Questionnaire has been validated for use in research with adults in some Western societies, but not in non-Western cultural-ethnic groups. We translated Camouflaging Autistic Traits Questionnaire into traditional Chinese and examined the use of this measure in Taiwanese adolescents via both self-report and caregiver-report in 100 autistic and 105 non-autistic adolescents. Both self-reported and caregiver-reported Chinese version Camouflaging Autistic Traits Questionnaire were composed of two factors (i.e. a "compensation-masking" subscale and an "assimilation" subscale). Both adolescent self-reported and caregiver-reported Chinese version Camouflaging Autistic Traits Questionnaire total score and subscales were reliable in measurement, and they highly correlated with each other. Taiwanese autistic adolescents were more likely to camouflage than non-autistic adolescents, especially on assimilation. Female autistic adolescents showed higher assimilation than male autistic adolescents. Higher camouflaging, especially assimilation, was associated with higher stress in autistic and non-autistic adolescents alike. Both self-reported and caregiver-reported Chinese version Camouflaging Autistic Traits Questionnaire were reliable and offered meaningful information to help us understand the social coping experiences of autistic and non-autistic adolescents.

A lack of efficacy of continuous theta burst stimulation over the left dorsolateral prefrontal cortex in autism: A double blind randomized sham-controlled trial

Although previous open-label trials suggest the therapeutic potential of inhibitory repetitive transcranial magnetic stimulation (rTMS) over the dorsolateral prefrontal cortex (DLPFC) in autism spectrum disorder (ASD), methodological caveats exist. We conducted an 8-week randomized, double-blind sham-controlled trial to investigate the efficacy of inhibitory continuous theta burst stimulation (cTBS, a variant of rTMS) over the left DLPFC in individuals with ASD. Sixty children, adolescents and young adults (aged 8-30 years) with ASD without co-occurring intellectual disabilities were randomized to a 16-session 8-week cTBS versus sham stimulation course, with a follow-up 4 weeks after the trial. The Active group was not superior to the Sham group in any clinical or neuropsychological metrics at Week 8 or Week 12. Time effects of 8-week cTBS on symptoms and executive function were remarkable in both Active and Sham groups, with comparable response rates and effect sizes of changes in symptoms/cognition between groups. Our results from a sufficiently powered sample do not endorse the superior efficacy of cTBS over the left DLPFC to the shamed stimulation for children, adolescents and adults with ASD. These findings suggest that earlier positive open-label trial findings may be generalized by generalized/placebo effects. This highlights the urgent need for more rTMS/TBS studies with rigorous trial designs in ASD.

Adolescent-Caregiver Agreement Regarding the School Bullying and Cyberbullying Involvement Experiences of Adolescents with Autism Spectrum Disorder

School bullying and cyberbullying victimization and perpetration are prevalent in adolescents with autism spectrum disorder (AASD). However, the levels of adolescent-caregiver agreement regarding the bullying involvement of AASD and the factors associated with these levels remain to be evaluated. In the present study, we evaluated the levels of adolescent-caregiver agreement on the school bullying and cyberbullying involvement experiences of AASD and the factors associated with the levels of agreement. This study included 219 dyads of AASD and their caregivers. The school bullying and cyberbullying involvement experiences of the participating AASD were assessed using the School Bullying Experience Questionnaire and the Cyberbullying Experiences Questionnaire, respectively. Attention-deficit/hyperactivity disorder, oppositional defiant disorder (ODD), depressive and anxiety symptoms, and autistic social impairment were also assessed. AASD and their caregivers had poor to fair levels of agreement regarding the school bullying and cyberbullying victimization and perpetration experiences of AASD. Severe inattention, hyperactivity-impulsivity, ODD, depressive and anxiety symptoms, and autistic social impairment were associated with high levels of adolescent-caregiver agreement. When assessing the bullying involvement experiences of AASD, mental health professionals should obtain information from multiple sources. In addition, the factors influencing the levels of agreement should be considered.

Lack of effects of four-week theta burst stimulation on white matter macro/microstructure in children and adolescents with autism

Following the published behavioral and cognitive results of this single-blind parallel sham-controlled randomized clinical trial, the current study aimed to explore the impact of intermittent theta burst stimulation (iTBS), a variant of excitatory transcranial magnetic stimulation, over the bilateral posterior superior temporal sulci (pSTS) on white matter macro/microstructure in intellectually able children and adolescents with autism. Participants were randomized and blindly received active or sham iTBS for 4 weeks (the single-blind sham-controlled phase). Then, all participants continued to receive active iTBS for another 4 weeks (the open-label phase). The clinical results were published elsewhere. Here, we present diffusion magnetic resonance imaging data on potential changes in white matter measures after iTBS. Twenty-two participants in Active-Active group and 27 participants in Sham-Active group underwent multi-shell high angular resolution diffusion imaging (64-direction for b = 2000 & 1000 s/mm², respectively) at baseline, week 4, and week 8. With longitudinal fixel-based analysis, we found no white matter changes following iTBS from baseline to week 4 (a null treatment by time interaction and a null within-group paired comparison in the Active-Active group), nor from baseline to week 8 (null within-group paired comparisons in both Active-Active and Sham-Active groups). As for the brain-symptoms relationship, we did not find baseline white matter metrics associated with symptom changes at week 4 in either group. Our results raise the question of what the minimal cumulative stimulation dose required to induce the white matter plasticity is.

White matter microstructural and morphometric alterations in autism: implications for intellectual capabilities

Background

Neuroimage literature of autism spectrum disorder (ASD) has a moderate-to-high risk of bias, partially because those combined with intellectual impairment (II) and/or minimally verbal (MV) status are generally ignored. We aimed to provide more comprehensive insights into white matter alterations of ASD, inclusive of individuals with II (ASD-II-Only) or MV expression (ASD-MV).

Methods

Sixty-five participants with ASD (ASD-Whole; 16.6 ± 5.9 years; comprising 34 intellectually able youth, ASD-IA, and 31 intellectually impaired youth, ASD-II, including 24 ASD-II-Only plus 7 ASD-MV) and 38 demographic-matched typically developing controls (TDC; 17.3 ± 5.6 years) were scanned in accelerated diffusion-weighted MRI. Fixel-based analysis was undertaken to investigate the categorical differences in fiber density (FD), fiber cross section (FC), and a combined index (FDC), and brain symptom/cognition associations.

Results

ASD-Whole had reduced FD in the anterior and posterior corpus callosum and left cerebellum Crus I, and smaller FDC in right cerebellum Crus II, compared to TDC. ASD-IA, relative to TDC, had no significant discrepancies, while ASD-II showed almost identical alterations to those from ASD-Whole vs. TDC. ASD-II-Only had greater FD/FDC in the isthmus splenium of callosum than ASD-MV. Autistic severity negatively correlated with FC in right Crus I. Nonverbal full-scale IQ positively correlated with FC/FDC in cerebellum VI. FD/FDC of the right dorsolateral prefrontal cortex showed a diagnosis-by-executive function interaction.

Limitations

We could not preclude the potential effects of age and sex from the ASD cohort, although statistical tests suggested that these factors were not influential. Our results could be confounded by variable psychiatric comorbidities and psychotropic medication uses in our ASD participants recruited from outpatient clinics, which is nevertheless closer to a real-world presentation of ASD. The outcomes related to ASD-MV were considered preliminaries due to the small sample size within this subgroup. Finally, our study design did not include intellectual impairment-only participants without ASD to disentangle the mixture of autistic and intellectual symptoms.

Conclusions

ASD-associated white matter alterations appear driven by individuals with II and potentially further by MV. Results suggest that changes in the corpus callosum and cerebellum are key for psychopathology and cognition associated with ASD. Our work highlights an essential to include understudied subpopulations on the spectrum in research.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13229-022-00499-1.

Contextual Factors Impact the Variability in ADHD Symptoms in Preschoolers with Situational Hyperactivity

Objective: This study examined preschoolers with teacher-reported or parent-reported situational hyperactivity, and whether they differed in terms of behavioral problems, attentional problems, and parenting perceptions. Method: We used the Conners' Kiddie Continuous Performance Test and the Color Flanker Task to assess 99 preschoolers with pervasive high-ADHD-symptoms (42), school-situational high-ADHD-symptoms (30), or home-situational high-ADHD-symptoms (27), plus 111 preschoolers with pervasive low-ADHD-symptoms. Parents and teachers reported externalizing/internalizing behavioral problems. Parenting perceptions were measured with the Parenting Stress Index-Short Form and a parenting perceptions scale. Results: Preschoolers with school-situational high-ADHD-symptoms had deficits in attentional control. Parents of preschoolers with home-situational high-ADHD-symptoms had higher levels of parental stress and perceived their parenting to be harsher. Preschoolers with pervasive high-ADHD-symptoms had deficits in attentional control, increased parental stress, and parents with harsher parenting perceptions. Conclusion: Preschoolers with situational high-ADHD-symptoms may have different contextual risk factors related to ADHD symptoms reported by parents versus teachers.

5-day Multi-Session Intermittent Theta Burst Stimulation over Bilateral Posterior Superior Temporal Sulci in Adults with Autism-a Pilot Study

Background

Theta burst stimulation (TBS), a patterned repetitive transcranial magnetic stimulation (rTMS) protocol with shorter simulation duration and lower stimulus intensity, could be a better protocol for individuals with autism spectrum disorder (ASD). Our study aimed to explore the impacts of intermittent TBS (iTBS) over the bilateral posterior superior temporal sulcus (pSTS) on intellectually able adults with ASD.

Methods

In this randomized, single-blinded, sham-controlled crossover trial, 13 adults with ASD completed iTBS for 5 consecutive days over the bilateral pSTS and inion (as a sham control) in a 16-weeks interval and in a randomly assigned order. The neuropsychological function was measured with the Wisconsin Card Sorting Test (WCST) for cognitive flexibility while the clinical outcomes were measured with both self-rate and parents-rate Autism Spectrum Quotient (AQ) before and after 5-day iTBS interventions.

Results

The results revealed significantly immediate effects of multi-session iTBS over the bilateral pSTS on parent-rate autistic symptoms in adults with ASD. The post-hoc analysis revealed the impacts of multi-session iTBS on cognitive flexibility were affected by baseline social-communicative impairment and baseline cognitive performance. Besides, the impacts of multi-session iTBS on clinical symptoms was affected by the concurrent psychotropic medication use and baseline autistic symptoms.

Conclusions

Given the caveat of the small sample size and discrepancy of multiple informants, this pilot study suggests the therapeutic potential of 5-day multi-session iTBS over the pSTS in adults with ASD. Individual factors modulating the response to rTMS should be explicitly considered in the future trial.

Intermittent theta burst stimulation over the posterior superior temporal sulcus for children with autism spectrum disorder: A 4-week randomized blinded controlled trial followed by another 4-week open-label intervention

The posterior superior temporal sulcus is a potential therapeutic target of brain stimulation for autism spectrum disorder. We conducted a 4-week randomized, single-blind parallel sham-controlled trial, followed by additional 4-week open-label intervention to evaluate the feasibility and efficacy regarding intermittent theta burst stimulation over the bilateral posterior superior temporal sulcus in autism spectrum disorder. In total, 78 intellectually able children and adolescents were randomized to the active ( n = 40) and sham groups ( n = 38). During the first 4 weeks, the active group received two-session/week intermittent theta burst stimulation, whereas the sham group received the same number of sham stimulation. After unblinding, both groups received eight-session real stimulation over the additional 4 weeks. In total, 91% participants completed the protocol with mild and transitory side-effects. There was no significant group-by-time interaction for active versus sham group on clinical symptoms and social cognitive performances in the first 4 weeks. The within-group analysis revealed 8 weeks (including a 4-week blind trial and a 4-week open-label intervention) of intermittent theta burst stimulation achieved greater efficacy than 4-week interventions. Participants with higher intelligence, better social cognitive performances, alongside less attention-deficit hyperactivity disorder severity at baseline, were more likely to be responders. Our study demonstrated the feasibility of long-term intermittent theta burst stimulation over the posterior superior temporal sulcus in children and adolescents with autism spectrum disorder. However, the findings from the first 4-week blind trial do not support the therapeutic efficacy of intermittent theta burst stimulation over the posterior superior temporal sulcus on the clinical symptoms and cognitive performance of social impairment, given the current stimulation protocol. The exploratory analyses suggest that the therapeutic efficacy might be moderated by several individual characteristics and more intermittent theta burst stimulation sessions.

Lay abstract

Intermittent theta burst stimulation is a varied form of repetitive transcranial magnetic non-invasive brain stimulation technique used to treat several neurological and psychiatric disorders. Its feasibility and therapeutic effects on the bilateral posterior superior temporal sulcus in children with autism are unknown. We conducted a single-blind, sham-controlled parallel randomized clinical trial in a hitherto largest sample of intellectually able children with autism ( N = 78). Participants randomized to the active group received two-session/week intermittent theta burst stimulation for continuous 8 weeks. Those in the sham group received two-session/week sham stimulations in the first 4 weeks and then active intervention for the following 4 weeks after unblinding. First, we found that continuous 8-week intermittent theta burst stimulation on the bilateral posterior superior temporal sulcus in children with autism is safe and tolerable. Second, we found that 8-week intermittent theta burst stimulation produced greater therapeutic efficacy, although we did not find any significant effects of 4-week intermittent theta burst stimulation on core symptoms and social cognitive performances in autism. Further analysis revealed that participants with higher intelligence and better social cognitive performance, alongside less attention-deficit hyperactivity disorder severity at baseline, were more likely to be responders. This study identified that the factors contribute to responders and the results suggest that longer courses of non-invasive brain stimulation may be needed to produce therapeutic benefits in autism, with consideration of heterogeneous responses.

Exploring the Variability in Reaction Times of Preschoolers at Risk of Attention-Deficit/Hyperactivity Disorder: an ex-Gaussian Analysis

Reaction times (RTs) are typically slower and more variable in individuals with attention-deficit/hyperactivity disorder (ADHD). Analysis of the ex-Gaussian RT distribution, which is described by mu, sigma (mean and standard deviation, respectively, of the normal distribution) and tau (that of exponential distribution), reveals that individuals with ADHD do not display overall slower RTs but have a high proportion of extremely slow RTs, represented by a high tau value. Although this is a vital component for describing ADHD-related RT variability in school-aged children, adolescents, and adults, it has not been thoroughly studied at the preschool age. We assessed 65 preschoolers at risk of ADHD and 98 typically developing preschoolers with the Conners' Kiddie Continuous Performance Test (K-CPT) and parental and teacher reports of ADHD symptoms. We found that preschoolers at risk of ADHD had greater values for RT standard deviation, sigma, and tau than typically developing preschoolers at long inter-stimulus intervals (ISIs) (3 s), but not at short ISIs (1.5 s). This suggests that attention problems in preschool children may only be apparent in the tasks with a relatively slow event rate. Our study demonstrates that the ex-Gaussian tau value is essential for describing the inattentive component of task performance in preschoolers with heightened ADHD symptoms. Furthermore, the fact that the tau effect was modulated by ISI suggests that the longer duration (3 s vs. 1.5 s) is a non-optimal energetic state in preschoolers at risk of ADHD, and that this might account for the subtle attentional flaw in task performance.

Characterizing intrinsic functional connectivity in relation to impaired self-regulation in intellectually able male youth with autism spectrum disorder

While a considerable number of youth with autism spectrum disorder exhibit impaired self-regulation (dysregulation), little is known about the neural correlates of dysregulation in autism spectrum disorder. In a sample of intellectually able boys with autism spectrum disorder (further categorized as those with and without dysregulation) and typically developing boys (aged 7–17 years), we conducted a multivariate connectome-wide association study to examine the intrinsic functional connectivity with resting-state functional magnetic resonance imaging. Dysregulation was defined by the sum of Attention, Aggression, and Anxiety/Depression subscales on the Child Behavior Checklist. We identified that both categorical and dimensional neural correlates of dysregulation in youth with autism spectrum disorder involved atypical connectivity among the components of multiple brain networks, especially between those subserving sensorimotor processing and salience encoding, beyond higher-level cognitive control circuitries. Interaction within the attention network might serve as autism spectrum disorder–specific neural correlates underpinning dysregulation. Our results highlight that the inter-individual variability in dysregulation might contribute to the inconsistency in the neuroimaging literature of autism spectrum disorder. Collectively, the present findings provide evidence to suggest that dysregulation might be considered as both categorical and dimensional moderators to parse heterogeneity of autism spectrum disorder.

Lay Abstract

Impaired self-regulation (i.e., dysregulation in affective, behavioral, and cognitive control), is commonly present in young people with autism spectrum disorder (ASD). However, little is known about what is happening in people’s brains when self-regulation is impaired in young people with ASD. We used a technique called functional MRI (which measures brain activity by detecting changes associated with blood flow) at a resting state (when participants are not asked to do anything) to research this in intellectually able young people with ASD. We found that brains with more connections, especially between regions involved in sensorimotor processing and regions involved in the processes that enable peoples to focus their attention on the most pertinent features from the sensory environment (salience processing), were related to more impaired self-regulation in young people with and without ASD. We also found that impaired self-regulation was related to increased communication within the brain system involved in voluntary orienting attention to a sensory cue (the dorsal attention network) in young people with ASD. These results highlight how different people have different degrees of dysregulation, which has been largely overlooked in the earlier brain imaging reports on ASD. This might contribute to understanding some of the inconsistencies in the existing published literature on this topic.

Cyberbullying Victimization and Perpetration in Adolescents with High-Functioning Autism Spectrum Disorder: Correlations with Depression, Anxiety, and Suicidality

The present study examined the associations between cyberbullying involvement and sociodemographic characteristics, autistic social impairment and attention-deficit/hyperactivity disorder and oppositional defiant disorder (ODD) symptoms in 219 adolescents with high-functioning autism spectrum disorder (ASD). Moreover, the associations between cyberbullying involvement and depression, anxiety, and suicidality were also examined. Adolescents self-reported higher rates of being a victim or perpetrator of cyberbullying than were reported by their parents. Increased age and had more severe ODD symptoms were significantly associated with being victims or perpetrators of cyberbullying. Being a victim but not a perpetrator of cyberbullying was significantly associated with depression, anxiety, and suicidality. Cyberbullying victimization and perpetration should be routinely surveyed in adolescents with high-functioning ASD.

Self-Reported and Parent-Reported School Bullying in Adolescents with High Functioning Autism Spectrum Disorder: The Roles of Autistic Social Impairment, Attention-Deficit/Hyperactivity and Oppositional Defiant Disorder Symptoms

The aim of this study was to examine the prevalence of self-reported and parent-reported bullying victimization, perpetration, and victimization-perpetration and the associations of autistic social impairment and attention-deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD) symptoms with bullying involvement in adolescents with high functioning autism spectrum disorder (ASD). A total of 219 adolescents with high functioning ASD participated in this study. The associations of sociodemographic characteristics, parent-reported autistic social impairment, and parent-reported ADHD and ODD symptoms with self-reported and parent-reported bullying victimization, perpetration, and victimization-perpetration were examined using logistic regression analysis. The results found that the agreement between self-reported and parent-reported bullying involvement was low. Compared with bullying involvement experiences reported by adolescents themselves, parents reported higher rates of pure bullying victimization (23.7% vs. 17.8%) and victimization-perpetration (28.8% vs. 9.1%) but a lower rate of pure bullying perpetration (5.9% vs. 9.1%). Deficit in socio-communication increases the risk of being pure victims and victim-perpetrators. Parent-reported victim-perpetrators had more severe ODD symptoms than did parent-reported pure victims.

Relationship between parenting stress and informant discrepancies on symptoms of ADHD/ODD and internalizing behaviors in preschool children

Parent and teacher ratings of child behaviors are often discrepant, and these discrepancies may be correlated with parenting stress. The present study explored whether various parenting stress factors are associated with discrepancies between parent and teacher ratings of attention-deficit/hyperactivity disorder and oppositional defiant disorder (ODD) as well as internalizing symptoms in preschool children. We recruited 299 Taiwanese preschool children (aged 4-6 years) from the community or via clinical referrals. A structural equation modeling was used to analyze the relationships among three factors derived from the Parenting Stress Index-Short Form and informant discrepancies on symptoms of inattention, hyperactivity/impulsivity, ODD, and internalizing behaviors. Scores reported by parents were higher for each of the symptoms examined than those reported by teachers, and the degree of agreement between informants ranged from low to moderate. The parental distress factor of parenting stress was associated only with parent ratings, whereas other factors of parenting stress-parent-child dysfunctional interaction and parents' stress resulted from their child's temperament-were correlated with both parent and teacher ratings. Only parental distress factor predicted informant discrepancies for all behavioral symptoms assessed. Our findings suggest that parental distress should be considered when parent rating scores show significant discrepancies from that of teacher rating scores.

The Impact of Single Session Intermittent Theta-Burst Stimulation over the Dorsolateral Prefrontal Cortex and Posterior Superior Temporal Sulcus on Adults with Autism Spectrum Disorder

Intermittent theta burst stimulation (iTBS), a patterned repetitive transcranial magnetic stimulation, was applied over the posterior superior temporal sulcus (pSTS) or dorsolateral prefrontal cortex (DLPFC) to explore its impact in adults with autism spectrum disorder (ASD). Among 25 adults with ASD, 19 (mean age: 20.8 years) completed the randomized, sham-controlled, crossover trial. Every participant received iTBS over the bilateral DLPFC, bilateral pSTS and inion (as a sham control stimulation) in a randomized order with a 1-week interval. Neuropsychological functions were assessed using the Conners' Continuous Performance Test (CCPT) and the Wisconsin Card Sorting Test (WCST). Behavioral outcomes were measured using the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) and the Social Responsiveness Scale (SRS). In comparison to that in the sham stimulation, the reaction time in the CCPT significantly decreased following single DLPFC session (p = 0.04, effect size = 0.71) while there were no significant differences in the CCPT and WCST following single pSTS session. Besides, the results in behavioral outcomes were inconsistent and had discrepancy between reports of parents and patients. In conclusion, a single session of iTBS over the bilateral DLPFC may alter the neuropsychological function in adults with ASD. The impacts of multiple-sessions iTBS over the DLPFC or pSTS deserve further investigations.

An Open-Label, Randomized Trial of Methylphenidate and Atomoxetine Treatment in Adults With ADHD

OBJECTIVE

To directly compare the efficacy of methylphenidate and atomoxetine in improving symptoms, social functions, and quality of life among adults with ADHD.

METHOD

This was an 8-to-10-week, open-label, head-to-head, randomized clinical trial with two treatment arms: immediate-release methylphenidate (IR-methylphenidate; n = 31) and atomoxetine once daily ( n = 32). The outcome measures included ADHD symptom severity, quality of life, and functional impairments.

RESULTS

We found a significant reduction in overall ADHD symptoms and improvement in social functions and quality of life for both groups at Weeks 4 to 5 and Weeks 8 to 10. There was no significant difference in the slope of improvements over time except that atomoxetine was superior to IR-methylphenidate in reducing hyperactive/impulsive symptoms at Weeks 4 to 5. There was no significant group difference in the rates of adverse effects.

CONCLUSION

Both IR-methylphenidate and atomoxetine are well tolerated and efficacious in ethnic Chinese adults with ADHD.

Atomoxetine could improve intra-individual variability in drug-naïve adults with attention-deficit/hyperactivity disorder comparably with methylphenidate: A head-to-head randomized clinical trial

OBJECTIVE

Intra-individual variability in reaction time (IIV-RT) is common in individuals with attention-deficit/hyperactivity disorder (ADHD). It can be improved by stimulants. However, the effects of atomoxetine on IIV-RT are inconclusive. We aimed to investigate the effects of atomoxetine on IIV-RT, and directly compared its efficacy with methylphenidate in adults with ADHD.

METHODS

An 8-10 week, open-label, head-to-head, randomized clinical trial was conducted in 52 drug-naïve adults with ADHD, who were randomly assigned to two treatment groups: immediate-release methylphenidate (n=26) thrice daily (10-20 mg per dose) and atomoxetine once daily (n=26) (0.5-1.2 mg/kg/day). IIV-RT, derived from the Conners' continuous performance test (CCPT), was represented by the Gaussian (reaction time standard error, RTSE) and ex-Gaussian models (sigma and tau). Other neuropsychological functions, including response errors and mean of reaction time, were also measured. Participants received CCPT assessments at baseline and week 8-10 (60.4±6.3 days).

RESULTS

We found comparable improvements in performances of CCPT between the immediate-release methylphenidate- and atomoxetine-treated groups. Both medications significantly improved IIV-RT in terms of reducing tau values with comparable efficacy. In addition, both medications significantly improved inhibitory control by reducing commission errors.

CONCLUSION

Our results provide evidence to support that atomoxetine could improve IIV-RT and inhibitory control, of comparable efficacy with immediate-release methylphenidate, in drug-naïve adults with ADHD. Shared and unique mechanisms underpinning these medication effects on IIV-RT awaits further investigation.

Regional brain volume differences between males with and without autism spectrum disorder are highly age-dependent

BACKGROUND

Neuroanatomical differences between individuals with and without autism spectrum disorder (ASD) were inconsistent in the literature. Such heterogeneity may substantially originate from age-differential effects.

METHODS

Voxel-based morphometry was applied in 86 males with ASD and 90 typically developing control (TDC) males (aged 7 to 29 years). Three steps of statistical modeling (model 1, multiple regression with age as a covariate; model 2, multiple regression further considering diagnosis-by-age interaction; model 3, age-stratified analyses) were performed to dissect the moderating effects of age on diagnostic group differences in neuroanatomy.

RESULTS

Across ages, males with and without ASD did not differ significantly in total gray matter (GM) or white matter (WM) volumes. For both groups, total GM volumes decreased and WM volumes increased with age. For regional volume, comparing with the model only held the age constant (model 1), the main effect of group altered when diagnosis-by-age interaction effects were considered (model 2). Here, participants with ASD had significantly greater relative regional GM volumes than TDC in the right inferior orbitofrontal cortex and bilateral thalamus; for WM, participants with ASD were larger than TDC in the bilateral splenium of corpus callosum and right anterior corona radiata. Importantly, significant diagnosis-by-age interactions were identified at the bilateral anterior prefrontal cortex, bilateral cuneus, bilateral caudate, and the left cerebellum Crus I for GM and left forceps minor for WM. Finally, age-stratified analyses (model 3) showed distinct patterns in GM and WM volumetric alterations in ASD among subsamples of children, adolescents, and adults.

CONCLUSIONS

Our findings suggest that the heterogeneous reports on the atypical neuroanatomy of ASD may substantially originate from age variation in the study samples. Age variation and its methodological and biological implications have to be carefully delineated in future studies of the neurobiology of ASD.

High levels of LDL-C combined with low levels of HDL-C further increase platelet activation in hypercholesterolemic patients

High levels of low-density lipoprotein cholesterol (LDL-C) enhance platelet activation, whereas high levels of high-density lipoprotein cholesterol (HDL-C) exert a cardioprotective effect. However, the effects on platelet activation of high levels of LDL-C combined with low levels of HDL-C (HLC) have not yet been reported. We aimed to evaluate the platelet activation marker of HLC patients and investigate the antiplatelet effect of atorvastatin on this population. Forty-eight patients with high levels of LDL-C were enrolled. Among these, 23 had HLC and the other 25 had high levels of LDL-C combined with normal levels of HDL-C (HNC). A total of 35 normocholesterolemic (NOMC) volunteers were included as controls. Whole blood flow cytometry and platelet aggregation measurements were performed on all participants to detect the following platelet activation markers: CD62p (P-selectin), PAC-1 (GPIIb/IIIa), and maximal platelet aggregation (MPAG). A daily dose of 20 mg atorvastatin was administered to patients with high levels of LDL-C, and the above assessments were obtained at baseline and after 1 and 2 months of treatment. The expression of platelets CD62p and PAC-1 was increased in HNC patients compared to NOMC volunteers (P<0.01 and P<0.05). Furthermore, the surface expression of platelets CD62p and PAC-1 was greater among HLC patients than among HNC patients (P<0.01 and P<0.05). Although the expression of CD62p and PAC-1 decreased significantly after atorvastatin treatment, it remained higher in the HLC group than in the HNC group (P<0.05 and P=0.116). The reduction of HDL-C further increased platelet activation in patients with high levels of LDL-C. Platelet activation remained higher among HLC patients regardless of atorvastatin treatment.

Risk predictors for hypnosedative-related complex sleep behaviors: a retrospective, cross-sectional pilot study

OBJECTIVE

To explore the risk predictors for complex sleep-related behaviors (CSBs) in subjects with a DSM-IV-diagnosed depressive disorder, anxiety disorder, adjustment disorder, somatoform disorder, or sleep disorder taking hypnosedative drugs.

METHOD

One hundred twenty-five subjects using hypnosedatives were enrolled from the psychiatric outpatient clinics of a medical center in Taiwan from May 2006 to July 2006. All subjects completed a questionnaire that included demographic data, current and childhood sleep habits, and CSBs after taking hypnosedatives. Complex sleep-related behaviors were defined as somnambulism with object manipulation, sleep-related eating, and other amnestic sleep-related behaviors. Demographic and clinical variables were compared in those with CSBs and those without. Then multiple logistic regression analyses were performed in order to identify significant risk predictors for CSBs.

RESULTS

Of the 125 subjects, 19 (15.2%) reported CSBs, all of whom took zolpidem. Among a total of 67 subjects taking zolpidem, those with CSBs were significantly more likely to be younger (P = .023), to be female (P = .011), to take a higher dose of zolpidem (> 10 mg/d; P < .001), and to not go to sleep immediately after taking zolpidem (P = .047). Multiple logistic regression analyses showed that a higher dose of zolpidem (> 10 mg/d) was the only significant predictor of CSBs (OR = 13.1; 95% CI, 2.6-65.9; P = .002).

CONCLUSIONS

This pilot study suggests that a higher dosage of zolpidem (> 10 mg/d) is the key risk predictor for CSBs.

Psychiatric comorbidity among children and adolescents with and without persistent attention-deficit hyperactivity disorder

OBJECTIVES

The aims of the present study were to examine the current psychiatric comorbidity among children and adolescents with and without persistent attention-deficit hyperactivity disorder (ADHD) as compared to school controls, and to determine the factors predicting psychiatric comorbidity.

METHOD

The sample included 296 patients (male, 85.5%), aged 11-17, who were diagnosed with DSM-IV ADHD at the mean age of 6.7 +/- 2.7 years and 185 school controls. The ADHD and other psychiatric diagnoses were made based on clinical assessments and confirmed by psychiatric interviews. The ADHD group was categorized into 186 patients (62.8%) with persistent ADHD and 110 (37.2%) without persistent ADHD.

RESULTS

Compared to the controls, the two ADHD groups were more likely to have oppositional defiant disorder (ODD), conduct disorder (CD), tics, mood disorders, past and regular use of substances, substance use disorders and sleep disorders (odds ratios (ORs) = 1.8-25.3). Patients with persistent ADHD had higher risks for anxiety disorders, particularly specific phobia than the controls. Moreover, patients with persistent ADHD were more likely to have ODD than their partially remitted counterparts. Advanced analyses indicated that more severe baseline ADHD symptoms predicted ODD/CD at adolescence; longer methylphenidate treatment duration was associated with an increased risk for tics and ODD/CD at adolescence; and older age predicted higher risks for mood disorders and substance use disorders.

CONCLUSION

Reduced ADHD symptoms at adolescence may not lead to decreased risks for psychiatric comorbidity, and identification of severe ADHD symptoms at childhood and age-specific comorbid patterns throughout the developmental stage is important to offset the long-term adverse psychiatric outcomes of ADHD.