Moderators and Other Predictors of Methylphenidate Response in Children and Adolescents with ADHD

Can response to ADHD medication be predicted?

Predictors for the pharmacological effect of ADHD medication in children and adolescents are lacking. This study examined clinically relevant factors in a large (N = 638) prospective cohort reflecting real-world evidence. Children and adolescents aged 6-17 diagnosed with ADHD were evaluated at baseline and three months following ADHD medication initiation. The outcome was measured as a reduction in total SNAP-IV (Swanson Nolan and Pelham teacher and parent rating scale) score at three months compared to baseline. Outcome groups were defined as Responders (≥ 40% reduction), Intermediate Responders (≥ 20 to < 40% reduction), and Non-responders (< 20% reduction). Included independent variables were the Autism Spectrum Questionnaire (ASSQ), the Spence Children's Anxiety Scale (SCAS), the Pediatric Side Effect Checklist (P-SEC), anthropometrics measures, geographical region, relative age, Children´s Global Assessment Scale (CGAS), Intelligence quotient (IQ), pharmacological treatment initiation month, ADHD symptom severity, ADHD presentation, and psychotic-like experiences. Multinomial logistic regression suggested that ADHD symptom severity, region, relative age, and stating ADHD medication at three-month follow-up were associated with the response outcome group. However, when validating the data with Bootstrap Forest, none of the variables were significant. Thus, in our large naturalistic cohort, we could not identify any clinically relevant factors that reliably predict pharmacological treatment outcomes.Trial registration: NCT02136147.

Predictors of Methylphenidate response in children and adolescents with ADHD: the role of sleep disturbances

Sleep Disturbances (SD) have been linked to children and adolescents with ADHD, impacting its progression and outcomes. Methylphenidate (MPH), a commonly used stimulant medication for ADHD treatment, has been observed to potentially influence SD as a side effect, while SD can in turn potentially affect the response to MPH. This study aimed to explore the potential role of SD on MPH response in children and adolescents with ADHD. At this aim, 43 children and adolescents with ADHD received a single dose of MPH and were assessed for attention before and after medication administration. As expected, the administration of MPH resulted in improved attention levels. Our data indicate that patients with higher SD experienced greater benefits from the medication, stabilizing Reaction Times Variability (VRTs). This suggests that SD might influence the response to MPH, with individuals exhibiting higher SD deriving more advantages from the treatment. In addition, we found that other factors, such as externalizing problems and IQ, interact with each other and with SD, influencing the response to stimulant medication. Early detection of SD, along with the study of cognitive and emotional-behavioral characteristics, could assist clinicians in predicting the effectiveness of MPH therapy in children and adolescents with ADHD. However, further research is necessary to gain a deeper understanding of the role of SD and other factors in the long-term effects of MPH.

Cognitive strengths in neurodevelopmental disorders, conditions and differences: A critical review

Neurodevelopmental disorders are traditionally characterised by a range of associated cognitive impairments in, for example, sensory processing, facial recognition, visual imagery, attention, and coordination. In this critical review, we propose a major reframing, highlighting the variety of unique cognitive strengths that people with neurodevelopmental differences can exhibit. These include enhanced visual perception, strong spatial, auditory, and semantic memory, superior empathy and theory of mind, along with higher levels of divergent thinking. Whilst we acknowledge the heterogeneity of cognitive profiles in neurodevelopmental conditions, we present a more encouraging and affirmative perspective of these groups, contrasting with the predominant, deficit-based position prevalent throughout both cognitive and neuropsychological research. In addition, we provide a theoretical basis and rationale for these cognitive strengths, arguing for the critical role of hereditability, behavioural adaptation, neuronal-recycling, and we draw on psychopharmacological and social explanations. We present a table of potential strengths across conditions and invite researchers to systematically investigate these in their future work. This should help reduce the stigma around neurodiversity, instead promoting greater social inclusion and significant societal benefits.

Predicting the Response of Children and Adolescents With ADHD to Methylphenidate: A Systematic Review

OBJECTIVE

To report the characteristics associated with response to methylphenidate (MPH) in children and adolescents with ADHD.

METHODS

Studies reporting potentials predictors of response to MPH were searched in Medline and Embase from January 1998 to March 2022. Narrative synthesis was performed.

RESULTS

Fifty-seven reports of 46 studies totaling 6,656 ADHD patients were included. No association appears between response to MPH and age, gender, MPH dosage, ADHD subtype, comorbidities nor socioeconomic status when considering a specific patient. No conclusion could be drawn about body weight, ADHD severity, intelligence quotient, and parental symptoms of depression or ADHD.

CONCLUSIONS

None of these potential predictors have proven their usefulness to predict response to MPH on an individual basis in clinical practice. In research, potential predictors should be measured, their association with response to MPH assessed, in order to control for confounding variables when modeling response to MPH.

Methylphenidate is more effective to improve inhibitory control and working memory compared to tDCS in children and adolescents with attention deficit/hyperactivity disorder: a proof-of-concept study

Introduction

Attention-deficit/hyperactivity disorder (ADHD) is characterized by an inappropriate, pervasive and persistent pattern of inattention, hyperactivity, and/or impulsivity and associated with substantial functional impairment. Despite considerable advances in the understanding and management of ADHD, some patients do not respond well to methylphenidate (MPH), the first-choice pharmacological treatment. Over the past decades, among non-invasive brain stimulation techniques, transcranial direct current stimulation (tDCS) has proven to be an effective and safe technique to improve behavior and cognition in children with neurodevelopmental disorders, including ADHD, by modifying cortical excitability. However, the effect of tDCS has never been directly compared with that of the MPH. The present randomized sham-controlled trial evaluated the effect of a single session of anodal tDCS compared with the administration of a single dose of MPH in children and adolescents with ADHD.

Methods

After completing baseline assessment (T0), 26 children and adolescents with ADHD were exposed to 3 conditions with a 24-h interval-sessions: (A) a single session of anodal tDCS over the left dorsolateral prefrontal cortex (DLPFC); (B) a single session of sham tDCS over the left DLPFC; (C) a single dose of MPH.

Results

Our results showed that after administering a single dose of MPH, children and adolescents with ADHD improved inhibitory control and visual-spatial WM compared with baseline, anodal, and sham tDCS. However, a single session of active tDCS over the left DLPFC was not effective compared with either baseline or sham tDCS.

Discussion

In conclusion, our protocol in ADHD involving a single tDCS session did not demonstrate consistent improvements in neurocognitive features compared with baseline, sham tDCS, or single MPH administration. Different protocols need to be developed to further test the effectiveness of tDCS in improving ADHD symptoms.