Atomoxetine and methylphenidate treatment in children with ADHD: the efficacy, tolerability and effects on executive functions

Examining daily stimulant medication use and sleep in adolescents with ADHD

Research has been inconclusive as to whether stimulant treatment causes or exacerbates sleep problems in adolescents with ADHD. This study examined sleep differences in adolescents with ADHD as a function of stimulant use. Participants were adolescents with ADHD (N = 159, ages 12-14). Parents reported on receipt of stimulant treatment (n = 92, 57.86%; n = 47 amphetamines, n = 45 methylphenidate). Adolescents wore actigraphs and completed daily diaries assessing sleep and daily use of stimulants for 2 weeks. Sleep parameters included daily-reported bedtime, sleep onset latency (SOL), sleep duration, daytime sleepiness, and difficulty waking the following morning; and actigraphy-measured sleep onset time, total time in bed, and sleep efficiency. We estimated between- and within-individual associations between stimulant medication use and sleep indices with all stimulants, after removing adolescents using sleep aids and weekend days, and as a function of stimulant type. Adolescent sleep did not differ between those receiving and not receiving stimulant treatment. Within individuals using stimulants, we largely observed no significant differences between medicated and unmedicated days, though findings were most often significant for school days only. Small effects were found indicating longer SOL, later sleep onset time, and more daytime sleepiness related to medication use. In contrast, there were slight improvements to sleep duration and sleep efficiency related to methylphenidate use, though methylphenidate was also associated with later sleep onset time and more daytime sleepiness. Given the inconsistent and small effects, findings suggest that stimulant medication may impact sleep, but does not appear to be a primary contributor to sleep problems in adolescents with ADHD.

Neuroplasticity to autophagy cross-talk in a therapeutic effect of physical exercises and irisin in ADHD

Adaptive neuroplasticity is a pivotal mechanism for healthy brain development and maintenance, as well as its restoration in disease- and age-associated decline. Management of mental disorders such as attention deficit hyperactivity disorder (ADHD) needs interventions stimulating adaptive neuroplasticity, beyond conventional psychopharmacological treatments. Physical exercises are proposed for the management of ADHD, and also depression and aging because of evoked brain neuroplasticity. Recent progress in understanding the mechanisms of muscle-brain cross-talk pinpoints the role of the myokine irisin in the mediation of pro-cognitive and antidepressant activity of physical exercises. In this review, we discuss how irisin, which is released in the periphery as well as derived from brain cells, may interact with the mechanisms of cellular autophagy to provide protein recycling and regulation of brain-derived neurotrophic factor (BDNF) signaling via glia-mediated control of BDNF maturation, and, therefore, support neuroplasticity. We propose that the neuroplasticity associated with physical exercises is mediated in part by irisin-triggered autophagy. Since the recent findings give objectives to consider autophagy-stimulating intervention as a prerequisite for successful therapy of psychiatric disorders, irisin appears as a prototypic molecule that can activate autophagy with therapeutic goals.

Networks of Neuropsychological Functions in the Clinical Evaluation of Adult ADHD

This study applied network analysis to explore the relations between neuropsychological functions of individuals in the clinical evaluation of attention-deficit/hyperactivity disorder (ADHD) in adulthood. A total of 319 participants from an outpatient referral context, that is, 173 individuals with ADHD (ADHD group) and 146 individuals without ADHD (n-ADHD group), took part in this study and completed a comprehensive neuropsychological assessment. A denser network with stronger global connectivity was observed in the ADHD group compared to the n-ADHD group. The strongest connections were consistent in both networks, that is, the connections between selective attention and vigilance, and connections between processing speed, fluency, and flexibility. Further centrality estimation revealed attention-related variables to have the highest expected influence in both networks. The observed relationships between neuropsychological functions, and the high centrality of attention, may help identify neuropsychological profiles that are specific to ADHD and optimize neuropsychological assessment and treatment planning of individuals with cognitive impairment.

Differential Treatment Effects of Methylphenidate and Atomoxetine on Executive Functions in Children with Attention-Deficit/Hyperactivity Disorder

Objectives: This study aimed to compare the efficacy of methylphenidate and atomoxetine on improving executive functions among children with attention-deficit/hyperactivity disorder (ADHD). Methods: This was an open-label, head-to-head, 3-month, randomized clinical trial with two-arm parallel-treatment groups: osmotic-release oral system methylphenidate (OROS-MPH; n = 79) and atomoxetine once daily (n = 78). Three major domains of executive functions were assessed, including response selection/inhibition, flexibility, and planning/working memory. The neuropsychological measures included the Conners' continuous performance test and the Cambridge Neuropsychological Test Automated Battery. Results: We found that both treatment groups showed improvement in executive functions (p-value <0.05 for the major indices of each domain). In addition, OROS-MPH was associated with a greater magnitude of improvement in the response selection/inhibition; the slope for detectability improvement in the Conners' continuous performance test was 0.06 for atomoxetine and 0.15 for OROS-MPH (p-value <0.01); the slope in rapid visual information processing was 2.22 for atomoxetine and 3.45 for OROS-MPH (p-value <0.05). Conclusion: Both OROS-MPH and atomoxetine improved various domains of executive functions in children with ADHD. There is greater improvement in response selection/inhibition among patients treated with OROS-MPH than those with atomoxetine. This trial was registered with ClinicalTrials.gov (no. NCT00916786).

Funções Executivas, Atenção e o Uso do Metilfenidato: Estudo de Revisão Sistemática

Resumo A influência do metilfenidato no desempenho das funções executivas e atenção tem sido bastante estudada no transtorno do déficit de atenção/hiperatividade. Este artigo consiste em um estudo de revisão sistemática de pesquisas publicadas entre 2010 e 2016 e que envolvem a verificação do perfil de desempenho em funções executivas e atenção de crianças e/ou adolescentes com TDAH que usam ou não metilfenidato. Foram utilizados os descritores executive functions AND methylphenidate, adhd, attention. A análise dos artigos revelou que o metilfenidato é considerado a substância de primeira escolha para o TDAH e que sua eficácia é mais comprovada no controle inibitório e na flexibilidade cognitiva. São necessários mais estudos no que se refere à memória de trabalho e atenção.

The Mechanism, Clinical Efficacy, Safety, and Dosage Regimen of Atomoxetine for ADHD Therapy in Children: A Narrative Review

Atomoxetine, a selective norepinephrine (NE) reuptake inhibitor, was approved for attention deficit/hyperactivity disorder (ADHD) treatment in children, adolescents and adults. We searched the database PubMed/MEDLINE (2000 to October 1, 2021). Only publications in English were considered. Atomoxetine inhibits the presynaptic norepinephrine transporter (NET), preventing the reuptake of NE throughout the brain along with inhibiting the reuptake of dopamine in specific brain regions such as the prefrontal cortex (PFC). The novel mechanism of atomoxetine also includes several new brain imaging studies and animal model studies. It is mainly metabolized by the highly polymorphic drug metabolizing enzyme cytochrome P450 2D6 (CYP2D6). Atomoxetine is effective and generally well tolerated. ADHD is often accompanied by multiple comorbidities. A series of studies have been published suggesting that atomoxetine is effective in the treatment of ADHD symptoms for children with various types of comorbidity. In some cases, it is possible that atomoxetine may have a positive influence on the symptoms of comorbidities. Atomoxetine can be administered either as a single daily dose or split into two evenly divided doses, and has a negligible risk of abuse or misuse. The latest guideline updated that clinical dose selection of atomoxetine was recommended based on both CYP2D6 genotype and the peak concentration. To have a more comprehensive understanding of atomoxetine, this review sets the focus on the mechanism, clinical efficacy and dosage regimen in detail, and also touches on those studies regarding adverse reactions of atomoxetine.

A Brief Replication Study Comparing Stimulants and Non-Stimulants for Attention-Deficit/Hyperactivity Disorder Treatment with a Focus on the Compliance, Efficacy, and Satisfaction

Objectives

The aim of this study was to compare the compliance, efficacy, and satisfaction associated with methylphenidate and atomoxetine for treating attention-deficit/hyperactivity disorder (ADHD).

Methods

The subjects were 44 patients who met the Diagnostic and Statistical Manual of Mental Disorder-5 diagnostic criteria for ADHD and were treated with methylphenidate or atomoxetine. The methylphenidate formulations included immediate release (IR), extended release (ER), and osmotic-controlled release oral delivery system (OROS). Patients and parents reported the average number of days per week the medication was taken. Efficacy was assessed using the ADHD Rating Scale. Satisfaction with medication scale (SAMS)–parent report form and SAMS–self-report form were used to evaluate parents’ and patients’ satisfaction, respectively.

Results

Patients and parents were more satisfied with methylphenidate than with atomoxetine. There were no significant differences in the compliance with and efficacy of methylphenidate and atomoxetine. Compliance with methylphenidate IR and ER was markedly lower than that with OROS methylphenidate or atomoxetine.

Conclusion

Methylphenidate OROS formulation can be considered a suitable option given its high rates of compliance, satisfaction, and efficacy.

Osmotic Release Oral System-Methylphenidate Hydrochloride (OROS-MPH) versus atomoxetine on executive function improvement and clinical effectiveness in ADHD: A randomized controlled trial

OBJECTIVES

The aim of this study to compare the clinic efficacy and effects of osmotic release oral system-methylphenidate and atomoxetine on executive function in children and adolescents with attention deficit hyperactivity disorder by a open-label, prospective, randomized controlled trial.

METHODS

The study was performed by 95 cases between ages 6 and 12 years who were diagnosed as attention-deficit/hyperactivity disorder (ADHD) and also 40 control individuals. In this study, Conners' Teacher Rating Scale (CTRS) was used in order to evaluate the efficacy of the treatment. Executive functions were assessed by the performance-based neuropsychological tests and ecological behavioral rating scales. Stroop test, cancellation test, and serial digit learning test were applied to performance based neuropsychological tests. Behavior Rating Inventory of Executive Function tests (BRIEFs) were used as behavioral assessment scales.

RESULTS

Among the ADHD groups, a reduction of over 40% in the CTRS subtest scores used to evaluate the efficacy of the treatment was considered to be an improvement, and no significant difference was found for both drugs. Both Osmotic Release Oral System-Methylphenidate Hydrochloride (OROS-MPH) and atomoxetine (ATX) significantly improved scores in neuropsychological tests.

CONCLUSION

Atomoxetine and OROS-MPH treatments have shown similar efficacy in clinical recovery and improvement on executive functions. However, disturbances in executive functions observed in children with ADHD are persistent despite treatment, when compared with the control group.

Effectiveness of Cognitive Training for School-Aged Children and Adolescents With Attention Deficit/Hyperactivity Disorder: A Systematic Review

Problems with executive functions (EF) are hallmark characteristics of Attention Deficit/Hyperactivity Disorder (ADHD). Therefore, this review analyzed the efficacy of cognitive training for EF in reducing ADHD symptomatology and improving educational, interpersonal, and occupational outcomes in children and adolescents with this disorder. A systematic search, using a PICO (population/participant, intervention/indicator, comparator/control, outcome) framework was carried out. From 2008 to 2018, resorting to EBSCOhost, the following databases were searched: Academic Search Complete, ERIC, MEDLINE with Full Text, PsycARTICLES, PsycINFO, and Psychology and Behavioral Sciences Collection. Twenty-two studies were included in this review. Of the 18 studies that reported performance-based measures of EF, 13 found improvements and five did not. Overall, 17 studies showed positive transfer effects on ADHD symptomatology, EF, academic improvement, reduced off-task behavior, and/or enhanced social skills. Of the nine studies that performed follow-up sessions, seven concluded that the treatment effects were maintained over time. In sum, results showed that cognitive training can be an effective intervention for children and adolescents with ADHD and might be a complementary treatment option for this disorder.

Computerized versus manual versions of the Wisconsin Card Sorting Test: Implications with typically developing and ADHD children

The aims of Study 1 (S1) were (a) to compare the task performance of 361 typically developing (TD) children aged 7 to 12 years, according to the mode of Wisconsin Card Sorting Test (WCST) administration (manual vs. computerized) and b) to examine the contributions of executive functions (EFs) (i.e., working memory [WM], shifting and inhibition) to each WCST version. The objectives of Study 2 (S2) were (a) to study the comparability of the results obtained from the manual version to the results from the computer version in 43 children with Attention Deficit/Hyperactivity Disorder (ADHD) and (b) to compare task performance on both versions between children with ADHD and TD children. The effect of age was only significant for the manual WCST. Regression analyses revealed that WM and shifting contributed to manual WCST performance, whereas WM and inhibition contributed to the performance on the computer version. We observed differences depending on the WCST mode of administration, as better scores for the manual version were recorded for both TD children and children with ADHD, despite similar performance on tasks involving other EFs. Additionally, children with ADHD performed worse than TD children on both versions. Our findings suggest that verbal face-to-face interactions would play a significant role in supporting children's abilities to solve novel situations characterized by uncertainty.

Effects of Long-Term Use of Prescription Methylphenidate on Myocardial Performance in Children with Attention-Deficit/Hyperactivity Disorder: A Tissue Doppler Imaging Study

OBJECTIVE

Many children diagnosed with attention-deficit/hyperactivity disorder are treated with methylphenidate (MPH). The purpose of this study was to evaluate the relationship between long-term use of osmotic-release oral system methylphenidate (OROS MPH) and cardiac functions.

METHODS

The study involved 116 subjects 6-18 years of age. Fifty-eight of these were in the case group and were using OROS MPH (extended-release capsules). Fifty-eight children not receiving treatment were included in the control group. Participants were also assessed using 12-channel electrocardiography (ECG), transthoracic 2D echocardiography, Doppler echocardiography, and tissue Doppler imaging (TDI). The findings obtained were compared using statistical methods.

RESULTS

No significant differences were determined between the case and control groups in terms of systolic blood pressure and diastolic blood pressure or 12-channel ECG findings. There was also no difference in 2D and M-mode measurements among the echocardiography findings. Of the TDI parameters obtained, only E' septal values differed significantly between the case and control groups. However, this was not at such a level as to indicate cardiac function impairment.

CONCLUSIONS

The study data showed that the echocardiographic parameters we measured resulted in no clinical difference between the children using MPH and the healthy controls. We conclude that MPH use in children does not impair cardiovascular functions at short-term follow-up.

The Effect of Methylphenidate and Atomoxetine on Heart Rate and Systolic Blood Pressure in Young People and Adults with Attention-Deficit Hyperactivity Disorder (ADHD): Systematic Review, Meta-Analysis, and Meta-Regression

Objectives: This meta-analysis aims to study the effects of atomoxetine and methylphenidate on heart rate (HR), systolic blood pressure (SBP), and a number of adverse cardiac events on patients receiving treatment for attention-deficit hyperactive disorder (ADHD) in comparison to placebo and between atomoxetine and methylphenidate. Methods: We searched the following databases: PubMed, EMBASE, and ScienceDirect. Meta-analysis was performed on studies that examined the relationships between methylphenidate or atomoxetine and HR, SBP, as well as a number of adverse cardiac events. These studies were either placebo-controlled or comparison studies between methylphenidate and atomoxetine. Meta-regression identified patient- and treatment-related factors that may contribute to heterogeneity. Results: Twenty-two studies were included and the total number of participants was 46,107. Children/adolescents and adults treated with methylphenidate had more significant increases in post- vs. pre-treatment HR (p < 0.001) and SBP (p < 0.001) than those treated by placebo. Children and adolescents treated with atomoxetine had more significant increases post- vs. pre-treatment HR (p = 0.025) and SBP (p < 0.001) than those treated with methylphenidate. Meta-regression revealed mean age of participants, mean dose, and duration of atomoxetine and methylphenidate as significant moderators that explained heterogeneity. There were no differences in the number of adverse cardiac events between participants with methylphenidate treatment and placebo or atomoxetine. Conclusions: Children/adolescents and adults treated with methylphenidate resulted in significant increases in post- vs. pre-treatment HR and SBP as compared to placebo. Similarly, children and adolescents treated with atomoxetine had significant increases in post- vs. pre-treatment HR and SBP than those treated with methylphenidate. These findings have potential implications for continuous monitoring of HR and SBP throughout the course of treatment although the risk for adverse cardiac events were insignificant.

Methylphenidate for attention deficit hyperactivity disorder (ADHD) in children and adolescents - assessment of adverse events in non-randomised studies

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder in childhood. The psychostimulant methylphenidate is the most frequently used medication to treat it. Several studies have investigated the benefits of methylphenidate, showing possible favourable effects on ADHD symptoms, but the true magnitude of the effect is unknown. Concerning adverse events associated with the treatment, our systematic review of randomised clinical trials (RCTs) demonstrated no increase in serious adverse events, but a high proportion of participants suffered a range of non-serious adverse events.

OBJECTIVES

To assess the adverse events associated with methylphenidate treatment for children and adolescents with ADHD in non-randomised studies.

SEARCH METHODS

In January 2016, we searched CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL, 12 other databases and two trials registers. We also checked reference lists and contacted authors and pharmaceutical companies to identify additional studies.

SELECTION CRITERIA

We included non-randomised study designs. These comprised comparative and non-comparative cohort studies, patient-control studies, patient reports/series and cross-sectional studies of methylphenidate administered at any dosage or formulation. We also included methylphenidate groups from RCTs assessing methylphenidate versus other interventions for ADHD as well as data from follow-up periods in RCTs. Participants had to have an ADHD diagnosis (from the 3rd to the 5th edition of the Diagnostic and Statistical Manual of Mental Disorders or the 9th or 10th edition of theInternational Classification of Diseases, with or without comorbid diagnoses. We required that at least 75% of participants had a normal intellectual capacity (intelligence quotient of more than 70 points) and were aged below 20 years. We excluded studies that used another ADHD drug as a co-intervention.

DATA COLLECTION AND ANALYSIS

Fourteen review authors selected studies independently. Two review authors assessed risk of bias independently using the ROBINS-I tool for assessing risk of bias in non-randomised studies of interventions. All review authors extracted data. We defined serious adverse events according to the International Committee of Harmonization as any lethal, life-threatening or life-changing event. We considered all other adverse events to be non-serious adverse events and conducted meta-analyses of data from comparative studies. We calculated meta-analytic estimates of prevalence from non-comparative cohorts studies and synthesised data from patient reports/series qualitatively. We investigated heterogeneity by conducting subgroup analyses, and we also conducted sensitivity analyses.

MAIN RESULTS

We included a total of 260 studies: 7 comparative cohort studies, 6 of which compared 968 patients who were exposed to methylphenidate to 166 controls, and 1 which assessed 1224 patients that were exposed or not exposed to methylphenidate during different time periods; 4 patient-control studies (53,192 exposed to methylphenidate and 19,906 controls); 177 non-comparative cohort studies (2,207,751 participants); 2 cross-sectional studies (96 participants) and 70 patient reports/series (206 participants). Participants' ages ranged from 3 years to 20 years. Risk of bias in the included comparative studies ranged from moderate to critical, with most studies showing critical risk of bias. We evaluated all non-comparative studies at critical risk of bias. The GRADE quality rating of the evidence was very low.Primary outcomesIn the comparative studies, methylphenidate increased the risk ratio (RR) of serious adverse events (RR 1.36, 95% confidence interval (CI) 1.17 to 1.57; 2 studies, 72,005 participants); any psychotic disorder (RR 1.36, 95% CI 1.17 to 1.57; 1 study, 71,771 participants); and arrhythmia (RR 1.61, 95% CI 1.48 to 1.74; 1 study, 1224 participants) compared to no intervention.In the non-comparative cohort studies, the proportion of participants on methylphenidate experiencing any serious adverse event was 1.20% (95% CI 0.70% to 2.00%; 50 studies, 162,422 participants). Withdrawal from methylphenidate due to any serious adverse events occurred in 1.20% (95% CI 0.60% to 2.30%; 7 studies, 1173 participants) and adverse events of unknown severity led to withdrawal in 7.30% of participants (95% CI 5.30% to 10.0%; 22 studies, 3708 participants).Secondary outcomesIn the comparative studies, methylphenidate, compared to no intervention, increased the RR of insomnia and sleep problems (RR 2.58, 95% CI 1.24 to 5.34; 3 studies, 425 participants) and decreased appetite (RR 15.06, 95% CI 2.12 to 106.83; 1 study, 335 participants).With non-comparative cohort studies, the proportion of participants on methylphenidate with any non-serious adverse events was 51.2% (95% CI 41.2% to 61.1%; 49 studies, 13,978 participants). These included difficulty falling asleep, 17.9% (95% CI 14.7% to 21.6%; 82 studies, 11,507 participants); headache, 14.4% (95% CI 11.3% to 18.3%; 90 studies, 13,469 participants); abdominal pain, 10.7% (95% CI 8.60% to 13.3%; 79 studies, 11,750 participants); and decreased appetite, 31.1% (95% CI 26.5% to 36.2%; 84 studies, 11,594 participants). Withdrawal of methylphenidate due to non-serious adverse events occurred in 6.20% (95% CI 4.80% to 7.90%; 37 studies, 7142 participants), and 16.2% were withdrawn for unknown reasons (95% CI 13.0% to 19.9%; 57 studies, 8340 participants).

AUTHORS' CONCLUSIONS

Our findings suggest that methylphenidate may be associated with a number of serious adverse events as well as a large number of non-serious adverse events in children and adolescents, which often lead to withdrawal of methylphenidate. Our certainty in the evidence is very low, and accordingly, it is not possible to accurately estimate the actual risk of adverse events. It might be higher than reported here.Given the possible association between methylphenidate and the adverse events identified, it may be important to identify people who are most susceptible to adverse events. To do this we must undertake large-scale, high-quality RCTs, along with studies aimed at identifying responders and non-responders.

Amphetamine Modestly Improves Conners' Continuous Performance Test Performance in Healthy Adults

OBJECTIVES

Amphetamine improves vigilance as assessed by continuous performance tests (CPT) in children and adults with attention deficit hyperactivity disorder (ADHD). Less is known, however, regarding amphetamine effects on vigilance in healthy adults. Thus, it remains unclear whether amphetamine produces general enhancement of vigilance or if these effects are constrained to the remediation of deficits in patients with ADHD.

METHODS

We tested 69 healthy adults (35 female) on a standardized CPT (Conner's CPT-2) after receiving 10- or 20-mg d-amphetamine or placebo. To evaluate potential effects on learning, impulsivity, and perseveration, participants were additionally tested on the Iowa Gambling Task (IGT) and Wisconsin Card Sorting Task (WCST).

RESULTS

Participants receiving placebo exhibited the classic vigilance decrement, demonstrated by a significant reduction in attention (D') across the task. This vigilance decrement was not observed, however, after either dose of amphetamine. Consistent with enhanced vigilance, the 20-mg dose also reduced reaction time variability across the task and the ADHD confidence index. The effects of amphetamine appeared to be selective to vigilance since no effects were observed on the IGT, WCST, or response inhibition/perseveration measures from the CPT.

CONCLUSIONS

The present data support the premise that amphetamine improves vigilance irrespective of disease state. Given that amphetamine is a norepinephrine/dopamine transporter inhibitor and releaser, these effects are informative regarding the neurobiological substrates of attentional control. (JINS, 2018, 24, 283-293).

A Systematic Review of the Use of Bupropion for Attention-Deficit/Hyperactivity Disorder in Children and Adolescents

INTRODUCTION

Attention-deficit/hyperactivity disorder (ADHD) is one of the most prevalent neuropsychiatric disorders of childhood and adolescence. Stimulants are usually the first choice of drug; however, as many as 20% of patients do not respond to them. Stimulants may also worsen comorbid sleep, mood, and anxiety disorders, and they are associated with problems of misuse and diversion. Bupropion, a dopamine and norepinephrine reuptake inhibitor, is a promising nonstimulant alternative with reports of positive outcomes for ADHD management in both adolescent and adult populations. This study systematically reviews clinical trials on the subject.

METHODS

Using the keywords bupropion or Wellbutrin or Zyban or Elontril and attention deficit hyperactivity disorder or ADHD or ADDH, a preliminary search on the PubMed and Ovid databases yielded 25,455 articles published in English between January 1, 1988 and May 1, 2016. Of these, there were only six articles on clinical trials involving children. Full articles were also reviewed for references of interest.

RESULTS

All available open, controlled, and randomized trials demonstrated bupropion's efficacy in improving ADHD symptoms. The three head-to-head trials found that bupropion had efficacy comparable to methylphenidate (p > 0.05). However, a large double-blind, placebo-controlled multicenter study of bupropion found smaller effect sizes for bupropion, as quantified using teacher and parent ratings of ADHD symptoms, than methylphenidate. In terms of tolerability, a head-to-head trial found that headache was observed more frequently in the methylphenidate-treated group than in the bupropion-treated group, whereas the frequency of other side effects did not differ significantly.

CONCLUSION

Current findings should be interpreted with caution because of the very limited database. Bupropion should be considered for pharmacological management of childhood and adolescent ADHD, but more randomized controlled trials with larger sample sizes are warranted. There is also some evidence of its benefits in children with comorbid ADHD and conduct, substance use, or depressive disorders.

Cardiovascular Effects of Stimulant and Non-Stimulant Medication for Children and Adolescents with ADHD: A Systematic Review and Meta-Analysis of Trials of Methylphenidate, Amphetamines and Atomoxetine

BACKGROUND

Many children and adolescents with attention deficit/hyperactivity disorder (ADHD) are treated with stimulant and non-stimulant medication. ADHD medication may be associated with cardiovascular effects. It is important to identify whether mean group effects translate into clinically relevant increases for some individual patients, and/or increase the risk for serious cardiovascular adverse events such as stroke or sudden death.

OBJECTIVES

To evaluate potential cardiovascular effects of these treatments, we conducted a systematic review and meta-analysis of the effects of methylphenidate (MPH), amphetamines (AMP), and atomoxetine (ATX) on diastolic and systolic blood pressure (DBP, SBP) and heart rate (HR) in children and adolescents with ADHD.

METHODS

We conducted systematic searches in electronic databases (PsychINFO, EMBASE and Medline) to identify published trials which involved individuals who were (i) diagnosed with ADHD and were aged between 0-18 years; (ii) treated with MPH, AMP or ATX and (iii) had their DBP and SBP and/or HR measured at baseline (pre) and the endpoint (post) of the study treatment. Studies with an open-label design or a double-blind randomised control design of any duration were included. Statistical analysis involved calculating differences between pre- and post-treatment measurements for the various cardiovascular parameters divided by the pooled standard deviation. Further, we assessed the percentage of clinically relevant increased BP or HR, or documented arrhythmias.

RESULTS

Eighteen clinical trials met the inclusion criteria (10 for MPH, 5 for AMP, and 7 for ATX) with data from 5837 participants (80.7% boys) and average duration of 28.7 weeks (range 4-96 weeks). All three medications were associated with a small, but statistically significant pre-post increase of SBP (MPH: standard mean difference [SMD] 0.25, 95% confidence interval [CI] 0.08-0.42, p < 0.01; AMP: SMD 0.09, 95% CI 0.03-0.15, p < 0.01; ATX: SMD 0.16, 95% CI 0.04-0.27, p = 0.01). MPH did not have a pre-post effect on DBP and HR. AMP treatment was associated with a small but statistically significant pre-post increase of DBP (SMD 0.16, CI 0.03-0.29, p = 0.02), as was ATX treatment (SMD 0.22, CI 0.10-0.34, p < 0.01). AMP and ATX were associated with a small to medium statistically significant pre-post increase of HR (AMP: SMD 0.37, CI 0.13-0.60, p < 0.01; ATX: SMD 0.43, CI 0.26-0.60, p < 0.01). The head-to-head comparison of the three medications did not reveal significant differences. Sensitivity analyses revealed that AMP studies of <18 weeks reported higher effect sizes on DBP compared with longer duration studies (F(1) = 19.55, p = 0.05). Further, MPH studies published before 2007 reported higher effect sizes on SBP than studies after 2007 (F(1) = 5.346, p = 0.05). There was no effect of the following moderators: type of medication, doses, sample size, age, gender, type of ADHD, comorbidity or dropout rate. Participants on medication reported 737 (12.6%) other cardiovascular effects. Notably, 2% of patients discontinued their medication treatment due to any cardiovascular effect. However, in the majority of patients, the cardiovascular effects resolved spontaneously, medication doses were changed or the effects were not considered clinically relevant. There were no statistically significant differences between the medication treatments in terms of the severity of cardiovascular effects.

CONCLUSIONS

Statistically significant pre-post increases of SBP, DBP and HR were associated with AMP and ATX treatment in children and adolescents with ADHD, while MPH treatment had a statistically significant effect only on SBP in these patients. These increases may be clinically significant for a significant minority of individuals that experience larger increases. Since increased BP and HR in general are considered risk factors for cardiovascular morbidity and mortality during adult life, paediatric patients using ADHD medication should be monitored closely and regularly for HR and BP.

Atomoxetine treatment for children and adolescents with Attention-Deficit/Hyperactivity Disorder (ADHD): a comprehensive meta-analysis of outcomes on parent-rated core symptomatology

Attention-Deficit/Hyperactivity Disorder (ADHD) impacts a significant number of children and adolescents and often leads to deleterious functional impairment. Psychostimulant medication has historically been the first line of pharmacological intervention, though recent years have seen greater attention paid to non-stimulant alternatives. The objective of the present study was to conduct the most comprehensive meta-analysis to date evaluating the efficacy of atomoxetine in reducing core symptomatology of ADHD according to parent report. Selection criteria were applied, and studies were located by searching electronic databases, review of reference sections, and contact with expert researchers; article searching began on 10/01/2013, and the final search was conducted on 09/01/2014. A total of 42 studies met inclusion criteria-33 with control groups and 9 without-for a total sample of 8398 individuals. For those receiving atomoxetine, the summary pre-post (e.g., standardized mean gain) effect size estimate was 1.37 (95% CI [1.24, 1.51], p < .001); atomoxetine was found to statistically significantly outperform control conditions overall (Z = 4.07, p < .001), though results differed by the type of control group; for instance, when comparing atomoxetine to alternative medications as controls, significant differences were no longer present. The non-stimulant atomoxetine led to significant improvement in core ADHD symptomatology and should be considered as a viable pharmacological treatment option for ADHD.

ADHD medications and cardiovascular adverse events in children and adolescents: cross-national comparison of risk communication in drug labeling

PURPOSE

Regulators approve written medical information for healthcare professionals and consumers, but the consistency of these sources has not been studied. We investigated the consistency of information regarding four cardiovascular risks of attention-deficit/hyperactivity disorder (ADHD) medications approved in four countries.

METHODS

Professional and consumer product labeling for five ADHD medications approved in Australia, Canada, the UK, and the USA were obtained in March/April 2016. Language describing the relationship between medication and elevated blood pressure and/or heart rate, myocardial infarction, stroke, and sudden death was extracted verbatim and classified into one of four categories based on the described relationship between medication and adverse event: "confirmed," "unconfirmed," "mixed," and "not mentioned." We judged the consistency of messages delivered to healthcare professionals and consumers as either "consistent" or "inconsistent."

RESULTS

We obtained 20 healthcare professional labels and 20 corresponding consumer labels for the five ADHD medications registered in all four countries. Not all professional and consumer labeling contained language regarding all four adverse events. Of the 80 theoretically evaluable drug-risk pairs, 38 (48%) were not evaluable because of absence of mention of the adverse event in the consumer label. For the remaining 42, the potential causal relationship was expressed consistently in professional and consumer labeling in 25 (60%) cases. The cardiovascular risk profile was not described consistently across all four countries for any of the five drugs.

CONCLUSIONS

Product labeling provides healthcare professionals and consumers with inconsistent messages regarding the potential causal relationship between stimulant use and specific cardiovascular risks in children and adolescents. Copyright © 2017 John Wiley & Sons, Ltd.

Comparative efficacy and safety of methylphenidate and atomoxetine for attention-deficit hyperactivity disorder in children and adolescents: Meta-analysis based on head-to-head trials

INTRODUCTION

Comparative efficacy and safety are important issues for appropriate drug selection for attention-deficit hyperactivity disorder (ADHD) treatment. Therefore we conducted a meta-analysis, where we compared atomoxetine (ATX) and methylphenidate (MPH) for ADHD treatment in children and adolescents.

METHOD

Literature retrieval was conducted in relevant databases from their inception to April 2016 to select head-to-head trials that compared ATX and MPH in children and adolescents. Outcomes like response rate, ADHD Rating Scale (ADHD-RS) score, and adverse events were compared between ATX and MPH treatments. The standardized mean difference (SMD) and risk ratio (RR) with their corresponding 95% confidence intervals (CIs) were used as the effect size for continuous data or dichotomous data, respectively.

RESULTS

Eleven eligible randomized-controlled trials were included, and two of them were double-blind, while the remaining were open-label. Compared to ATX, MPH showed a higher response rate (RR = 1.14, 95% CI [1. 09, 1.20]), decreased inattention (SMD = -0.13, 95% CI [-0.25, -0.01]) and lower risk of adverse events (drowsiness: RR = 0.17, 95% CI [0.11, 0.26; nausea: RR = 0.49; 95% CI [0.29, 0.85; vomiting: RR = 0.41, 95% CI [0.27, 0.63]). However, MPH presented a higher risk of insomnia than ATX (RR = 2.27, 95% CI [1.63, 3.15], p < .01).

CONCLUSION

Results of the meta-analysis add additional evidence of the effectiveness of both ATX and MPH and suggest that MPH should be a first treatment option in most patients with ADHD.

Efficacy and Tolerability of Different Interventions in Children and Adolescents with Attention Deficit Hyperactivity Disorder

BACKGROUND

Our study is an analysis of multiple publications involving assessing the comparable efficacy and tolerability of six interventions, which are lisdexamfetamine dimesylate (LDX), atomoxetine (ATX), methylphenidate (MPH), clonidine hydrochloride (CLON), guanfacine extended release (GXR), and bupropion, for young patients (6-18 years old) suffering from attention deficit hyperactivity disorder (ADHD).

METHODS

A conventional meta-analysis (MA) was performed to give direct comparisons and a network meta-analysis (NMA) was used to show the combination of direct and indirect evidence. Ranking preference for all the interventions under a certain outcome was given by the surface of cumulative ranking curve area (SUCRA).

RESULTS

Overall, 15,025 participants from 73 studies were involved in our analysis. In the pairwise MA, LDX was associated with less withdrawal than ATX for lack of efficacy. MPH showed less effectiveness than LDX according to ADHD Rating Scale score. Based on the analysis of our NMA, significant results of efficacy that LDX is a competitive drug were observed when evaluating LDX in comparison with other drugs except for CLON. ATX and GXR presented higher rates of abdominal pain morbidity versus inactive treatment.

CONCLUSION

The stimulants LDX and MPH are still highly recommended because they are highly effective and are tolerated well by patients. Among the non-stimulants, CLON can be taken into consideration for its appreciable effectiveness and tolerability. ATX and GXR can be seen as moderate choices.

The Safety of Atomoxetine for the Treatment of Children and Adolescents with Attention-Deficit/Hyperactivity Disorder: A Comprehensive Review of Over a Decade of Research

Atomoxetine is a noradrenergic reuptake inhibitor prescribed for attention-deficit/hyperactivity disorder (ADHD) that first gained approval in the USA in 2002 and has been authorized in 97 countries worldwide. The aim of this paper is to comprehensively review publications that addressed one or more of seven major safety topics relevant to atomoxetine treatment of children and adolescents (aged ≥6 years) diagnosed with ADHD. While the review focuses on children and adolescents, publications in which data from patients aged >18 years and from 6 to 18 years were analyzed in the same dataset were included. Using a predefined search strategy, including agreement of two reviewers when selecting papers, reduced the potential for bias. Using this process, we identified 70 eligible papers (clinical trials, epidemiological studies, and case reports) across the seven topics. We also referred to the European Summary of Product Characteristics (SPC) and US label. We found 15 papers about suicidality, three about aggression/hostility, seven about psychosis/mania, six about seizures, seven about hepatic effects, 29 about cardiovascular effects, and 28 about growth and development. The main findings (i.e., those from the largest and most well-conducted studies/analyses) are as follows. A large register-based study of pediatric and adult patients (6818 received atomoxetine) calculated a hazard ratio of 0.96 for suicide-related events during treatment with atomoxetine, and a meta-analysis of 23 placebo-controlled studies (N = 3883), published in 2014, found no completed suicides and no statistically significant association between atomoxetine and suicidality. The frequency of aggression/hostility was not statistically significantly higher with atomoxetine, e.g., experienced by 1.6 % (N = 21/1308) of atomoxetine-treated patients versus 1.1 % (N = 9/806) of placebo-treated patients in one meta-analysis. Symptoms of psychosis and mania were mainly observed in patients with comorbid bipolar disorder/depression. Based on spontaneous reports, during a 2-year period when 2.233 million adult and pediatric patients were exposed to atomoxetine, the reporting rate for seizures was 8 per 100,000 patients. In the manufacturer's database, atomoxetine was a "probable cause" of three hepatic adverse events (AEs) (all reversible hepatitis), and 133 hepatic AEs had possible confounding factors and were "possibly related" to atomoxetine, during 4 years when atomoxetine exposure had reached about 4.3 million patients. Rare cases of severe liver injury are described in the US label and European SPC; a case requiring liver transplantation is described in the US label. In a comprehensive review of a clinical trials database (N = 8417 received atomoxetine), most pediatric patients experienced modest increases in heart rate and blood pressure, and 8-12 % experienced more pronounced changes (≥20 bpm, ≥15 to 20 mmHg). However, in three long-term analyses (≥2 years), blood pressure was within age norms, and few patients discontinued due to cardiovascular AEs. As described in the European SPC, QT interval prolongation is uncommon, e.g., in an open-label study, 1.4 % of 711 children and adolescents had prolonged QTc intervals (≥450 ms in males, ≥470 ms in females) that were not clinically significant at ≥3 years of treatment with atomoxetine. The European SPC warns about potential QT interval prolongation in patients with a personal or family history, or if atomoxetine is administered with other drugs that potentially affect the QT interval. Decreases in growth (weight and height gain) occurred and were greatest in patients of above average weight and height, but appeared to recover over 2-5 years of atomoxetine treatment. In conclusion, suicidality, aggression/hostility, psychosis, seizures, liver injuries, and prolonged QT interval are uncommon or rare in children and adolescents treated with atomoxetine, based on data from the predefined search and from the European SPC. Overall, the data that we assessed from our search do not suggest that associations exist between atomoxetine and suicidality or seizures. The data also suggest that an association may not exist between atomoxetine and aggression/hostility. While atomoxetine may affect the cardiovascular system, the data suggest these effects are not clinically significant in most patients. Reductions in growth appear to be reversible in the long term.

Anxiety reduction on atomoxetine and methylphenidate medication in children with ADHD

BACKGROUND

Atomoxetine and methylphenidate are widely used to treat attention-deficit-hyperactivity disorder (ADHD) with similar effectiveness after 8 weeks of treatment, when atomoxetine has reached its a full effect. Both drugs have also been shown to have an effect on comorbid anxiety. To the best of our knowledge, no study has compared their effect on the dynamics of anxiety symptom reduction. The aim of this study was to compare the medication effect on core and comorbid anxiety symptom dynamics in children with ADHD.

METHODS

Sixty-nine patients participated in the study: 36 patients were taking atomoxetine and 33 patients, methylphenidate. Therapeutic effect on core symptoms of ADHD was measured on the ADHD-rating scale IV, and symptoms of anxiety were measured using the Conners Parent Rating Scale (CPRS). Symptoms were measured prior to and every 2 weeks during 8 weeks of treatment.

RESULTS

There was a significant decrease in CPRS anxiety subscale score in both medication groups. Anxiety subscale score was significantly lower in the atomoxetine group in the fourth week, and lasted through to 8 weeks of medication.

CONCLUSION

Both atomoxetine and methylphenidate reduced the symptoms of ADHD and anxiety. Atomoxetine was more effective in anxiety symptom reduction from the fourth week of treatment.

Osmotic Release Oral System Methylphenidate Versus Atomoxetine for the Treatment of Attention-Deficit/Hyperactivity Disorder in Chinese Youth: 8-Week Comparative Efficacy and 1-Year Follow-Up

OBJECTIVE

The purpose of this study was to compare the short-term efficacy, tolerability, and 1-year adherence in Chinese children and adolescents with attention-deficit/hyperactivity disorder (ADHD) treated with either osmotic release oral system methylphenidate (OROS MPH) or atomoxetine (ATX).

METHODS

Children and adolescents meeting Diagnostic and Statistical Manual of Mental Disorders, 4th ed. (DSM-IV) criteria for ADHD were randomly assigned to receive either OROS MPH (n = 119) or ATX (n = 118). Participants underwent a 1-4 week dose titration period to determine optimal dose, and then were maintained on that dose for 4 weeks (maintenance period). Assessment for efficacy was conducted every week over the titration period and at the end of the maintenance period. The primary efficacy measure was the investigator-rated total ADHD Rating Scale-IV (ADHD-RS-IV) score. Response was further classified as remission (ADHD-RS-IV [18 or 9 items] average score ≤1), robust improvement (ADHD-RS-IV ≥40% decrease in total score), or improvement (≥ 25% decrease in total score) at the end of maintenance period. Medication adherence (taking medication at least 5 days in 1 week) and reasons for nonadherence were evaluated every week over the titration period, at the end of maintenance period, and then at 3, 6, and 12 months.

RESULTS

At the end of maintenance period, both OROS MPH and ATX were associated with significant and similar reductions from baseline in ADHD symptoms. Percentages achieving remission, robust improvement, and improvement were comparable for OROS MPH and ATX treatment (35.3% vs. 37.1%, 45.4% vs. 44.8%, 65.5% vs. 66.4%). Medication use decreased over time for both treatments; however, at end of maintenance period, 3 month, 6 month, and 1 year follow-ups, subjects in the OROS MPH group were more likely to be compliant with treatment (74.8%, 50.4%, 38.7%, and 21.8% for OROS MPH vs. 52.5%, 33.9%, 12.7%, and 3.4% for ATX) ( p < 0.05). The most common reasons for nonadherence were adverse events and lack of efficacy.

CONCLUSIONS

Both OROS MPH and ATX resulted in similar reductions in ADHD symptoms in Chinese children and adolescents with ADHD. Long-term adherence with medication was poor in general, although somewhat better with OROS MPH than with ATX.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov , Identifier: NCT01065259.

Advanced Test of Attention in Children with Attention-Deficit/Hyperactivity Disorder in Japan for Evaluation of Methylphenidate and Atomoxetine Effects

Objective

This study was conducted to validate the Advanced Test of Attention (ATA) of the visual attention version of Japanese children with attention deficit/hyperactivity disorder (ADHD) and to evaluate the efficacy of methylphenidate (OROS-MPH) and atomoxetine medications.

Methods

To assess pharmacotherapy efficacy, the visual version of ATA was administered to 42 children with ADHD. Results were assessed using discriminant analysis, ANOVA for indices of ATA before and after medication treatment, and correlation analysis between the improvement of indices of ATA and clinical symptoms during medication treatment.

Results

Discriminant analysis showed that 69.0% of ADHD children were assigned correctly. The T score of commission errors increased as the trial progressed on the medication-off condition. T scores of commission errors and standard deviation of response times on medication-on condition were low compared to the medication-off condition. A few significant correlations were found between the improvements of indices of ATA and ADHD-Rating Scale (RS) during treatment.

Conclusion

The performance of the visual version of ATA on medication-off condition reflected the features of ADHD. Furthermore, the medication treatment effects were confirmed sufficiently. In addition, results suggest that indices of ATA reflected aspects of ADHD symptoms that are difficult to elucidate for ADHD-RS. For assessing symptoms and effects of medical treatment in children with ADHD, ATA might be a useful assessment tool.

An Open-Label, Randomized Trial of Methylphenidate and Atomoxetine Treatment in Children with Attention-Deficit/Hyperactivity Disorder

OBJECTIVE

The efficacy of both methylphenidate and atomoxetine has been established in placebo-controlled trials. The present study aimed to directly compare the efficacy of methylphenidate and atomoxetine in improving symptoms among children with attention-deficit/hyperactivity disorder (ADHD).

METHODS

The study sample included 160 drug-naïve children and adolescents 7-16 years of age, with DSM-IV-defined ADHD, randomly assigned to osmotic-release oral system methylphenidate (OROS-methylphenidate) (n=80) and atomoxetine (n=80) in a 24 week, open-label, head-to-head clinical trial. The primary efficacy measure was the score of the ADHD Rating Scale-IV Parents Version: Investigator Administered and Scored (ADHD-RS-IV). The secondary efficacy measures included the Clinical Global Impressions-ADHD-Severity (CGI-ADHD-S) and Chinese Swanson, Nolan, and Pelham IV scale (SNAP-IV), based on the ratings of investigators, parents, teachers, and subjects.

RESULTS

At week 24, mean changes in ADHD-RS-IV Inattention scores were 13.58 points (Cohen's d, -3.08) for OROS-methylphenidate and 12.65 points (Cohen's d, -3.05) for atomoxetine; and mean changes in ADHD-RS-IV Hyperactivity-Impulsivity scores were 10.16 points (Cohen's d, -1.75) for OROS-methylphenidate and 10.68 points (Cohen's d, -1.87) for atomoxetine. In terms of parent-, teacher-, and self-ratings on behavioral symptoms, both of the two treatment groups significantly decreased on the SNAP-IV scores at the end-point, with effect sizes ranging from 0.9 to 0.96 on the Inattention subscale and from 0.61 to 0.8 on the Hyperactivity/Impulsivity subscale for OROS-methylphenidate; and from 0.51 to 0.88 on the Inattention subscale and from 0.29 to 0.57 on the Hyperactivity/Impulsivity subscale for atomoxetine. No statistically significant differences between treatment groups were observed on the outcome measures. Vomiting, somnolence, and dizziness were reported more often for atomoxetine than for OROS-methylphenidate, whereas insomnia was reported more often for OROS-methylphenidate than for atomoxetine.

CONCLUSIONS

After 24 weeks of treatment, OROS-methylphenidate and atomoxetine had comparable efficacy in reducing core ADHD symptoms in drug-naïve children and adolescents with ADHD.

Effects of Atomoxetine and Osmotic Release Oral System-Methylphenidate on Executive Functions in Patients with Combined Type Attention-Deficit/Hyperactivity Disorder

OBJECTIVE

The aim of this study was to evaluate and compare the effects of atomoxetine (ATX) and osmotic release oral system-methylphenidate (OROS-MPH) therapies on executive functions, activities, treatment response time, and adverse effects based on discernible clinical effects in children with combined type attention-deficit/hyperactivity disorder (ADHD).

METHODS

The study sample consisted of 43 children 7-12 years of age, who presented to the outpatient clinic with inattention, hyperactivity, and impulsivity for the first time, and were diagnosed as having combined type ADHD according to Diagnostic and Statistical Manual of Mental Disorders, 4th ed. (DSM-IV) criteria but had not previously used any medication for ADHD. The Wisconsin Card Sorting Test (WCST), Stroop Test TBAG Form (STP), and Visual Auditory Digit Span B (VADS B) were applied to all the patients included. Neuropsychological tests were repeated in 33 patients with good clinical recovery based on the Clinical Global Impressions-Improvement (CGI-I) scale (CGI-I ≤2) at the week in which clinical recovery was observed. The time limit for treatment response was set as 20 weeks.

RESULTS

It was found that there was significantly increased performance in executive functions with ATX and OROS-MPH in both groups. It was seen that although significantly increased performance was achieved in both perseveration and conceptual learning and reasoning domains by both agents, there was increased performance in more domains by the OROS-MPH group in WSCT. Mean doses were 1.31±0.37 mg/kg/day in the ATX group and 0.90±0.29 mg/kg/day in the OROS-MPH group. Comparable effectiveness (76.19% for ATX vs. 77.27% for OROS-MPH) and adverse effects (57.14% for ATX vs. 54.54% for OROS-MPH) were detected in both groups, whereas there was a significant difference in clinical response times between the groups (13 weeks for ATX vs. 7 weeks for OROS-MPH, p <0.001).

CONCLUSIONS

At the end of the study, it was seen that clinical recovery achieved by ATX and OROS-MPH therapy was associated with improved cognitive processes, and that these agents do not only lead to behavioral changes but also to an improvement in cognitive processes. In addition, improvements in cognitive processes occurred simultaneously with behavioral recovery. Behavior is the result of neurocognitive processes, and further studies on the domains that these drugs affect, or the way in which these agents exert their effects, are needed.

Increased prefrontal hemodynamic change after atomoxetine administration in pediatric attention-deficit/hyperactivity disorder as measured by near-infrared spectroscopy

AIM

Atomoxetine, approved in Japan for the treatment of pediatric attention-deficit/hyperactivity disorder (ADHD) in April 2009, is a nonstimulant that is thought to act presynaptically via the inhibition of norepinephrine reuptake. Near-infrared spectroscopy is a non-invasive optical tool that can be used to study oxygenation and hemodynamic changes in the cerebral cortex. The present study examined the effects of a clinical dose of atomoxetine on changes in prefrontal hemodynamic activity in children with ADHD, as measured by near-infrared spectroscopy using the Stroop Color-Word Task.

METHODS

Ten children with ADHD participated in the present study. We used 24-channel near-infrared spectroscopy to measure the relative concentrations of oxyhemoglobin in the frontal lobes of participants in the drug-naïve condition and those who had received atomoxetine for 8 weeks. Measurements were conducted every 0.1 s during the Stroop Color-Word Task. We used the ADHD Rating Scale-IV-Japanese version (Home Version) to evaluate ADHD symptoms.

RESULTS

We found a significant decrease in ADHD Rating Scale-IV-Japanese version scores, from 30.7 to 22.6 (P=0.003). During the Stroop Color-Word Task, we found significantly higher levels of oxyhemoglobin changes in the prefrontal cortex of participants in the atomoxetine condition compared with those in the drug-naïve condition.

CONCLUSIONS

This increase in oxyhemoglobin changes might indicate an intensified prefrontal hemodynamic response induced by atomoxetine. Near-infrared spectroscopy is a sensitive tool for measuring the pharmacological effects of atomoxetine in children with ADHD.

The efficacy of atomoxetine for the treatment of children and adolescents with attention-deficit/hyperactivity disorder: a comprehensive review of over a decade of clinical research

Atomoxetine was first licensed to treat attention-deficit/hyperactivity disorder (ADHD) in children and adolescents in the US in 2002. The aim of this paper is to comprehensively review subsequent publications addressing the efficacy of atomoxetine in 6- to 18-year-olds with ADHD. We identified 125 eligible papers using a predefined search strategy. Overall, these papers demonstrate that atomoxetine is an effective treatment for the core ADHD symptoms (effect sizes 0.6-1.3, vs. placebo, at 6-18 weeks), and improves functional outcomes and quality of life, in various pediatric populations with ADHD (i.e., males/females, patients with co-morbidities, children/adolescents, and with/without prior exposure to other ADHD medications). Initial responses to atomoxetine may be apparent within 1 week of treatment, but can take longer (median 23 days in a 6-week study; n=72). Responses often build gradually over time, and may not be robust until after 3 months. A pooled analysis of six randomized placebo-controlled trials (n=618) indicated that responses at 4 weeks may predict response at 6-9 weeks, although another pooled analysis of open-label data (n=338) suggests that the probability of a robust response to atomoxetine [≥40% decrease in ADHD-Rating Scale (ADHD-RS) scores] may continue to increase beyond 6-9 weeks. Atomoxetine may demonstrate similar efficacy to methylphenidate, particularly immediate-release methylphenidate, although randomized controlled trials are generally limited by short durations (3-12 weeks). In conclusion, notwithstanding these positive findings, before initiating treatment with atomoxetine, it is important that the clinician sets appropriate expectations for the patient and their family with regard to the likelihood of a gradual response, which often builds over time.

The Ethics of Neuroenhancement

According to several recent studies, a big chunk of college students in North America and Europe uses so called ‘smart drugs' to enhance their cognitive capacities aiming at improving their academic performance. With these practices, there comes a certain moral unease. This unease is shared by many, yet it is difficult to pinpoint and in need of justification. Other than simply pointing to the medical risks coming along with using non-prescribed medication, the salient moral question is whether these practices are troubling in and of themselves. In due consideration of empirical insights into the concrete effects of smart drugs on brain and behavior, our attempt is to articulate wherein this moral unease consists and to argue for why the authors believe cognitive enhancement to be morally objectionable. The authors will contend that the moral problem with these practices lies less in the end it seeks, than in the underlying human disposition it expresses and promotes. Some might ask, what is wrong with molding our cognitive capacities to achieve excellence, get a competitive edge, or, as the whim takes us? In all of these occasions, the usage of smart drugs serves a certain goal, a telos. The goal is, broadly speaking, this: outsmarting opponents in an arms race for limited resources and thereby yielding a competitive edge. In plain words: competition is valued higher than cooperation or solidarity. What is wrong with striving for this goal? The authors submit that the question whether people really want to live in a society that promotes the mentality ‘individual competition over societal cooperation' deserves serious consideration. In developing their answer, the authors draw on an ‘Ethics of Constraint' framework, arguing that widespread off-label use of smart drugs bears the risk of negative neural/behavioral consequences for the individual that might, in the long run, be accompanied by changing social value orientations for the worse.

Differential impact of methylphenidate and atomoxetine on sustained attention in youth with attention-deficit/hyperactivity disorder

BACKGROUND

This study examined the effects of atomoxetine (ATX) and OROS methylphenidate (MPH) on laboratory measures of inhibitory control and attention in youth with attention-deficit/hyperactivity disorder (ADHD). It was hypothesized that performance would be improved by both treatments, but response profiles would differ because the medications work via different mechanisms.

METHODS

One hundred and two youth (77 male; mean age = 10.5 ± 2.7 years) with ADHD received ATX (1.4 ± 0.5 mg/kg) and MPH (52.4 ± 16.6 mg) in a randomized, double-blind, crossover design. Medication was titrated in 4-6-week blocks separated by a 2-week placebo washout. Inhibitory control and attention measures were obtained at baseline, following washout, and at the end of each treatment using Conners' Continuous Performance Test II (CPT-II), which provided age-adjusted T-scores for reaction time (RT), reaction time variability (RT variability), and errors. Repeated-measures analyses of variance were performed, with Time (premedication, postmedication) and Treatment type (ATX, MPH) entered as within-subject factors. Data from the two treatment blocks were checked for order effects and combined if order effects were not present.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov: NCT00183391.

RESULTS

Main effects for Time on RT (p = .03), RTSD (p = .001), and omission errors (p = .01) were significant. A significant Drug × Time interaction indicated that MPH improved RT, RTSD, and omission errors more than ATX (p < .05). Changes in performance with treatment did not correlate with changes in ADHD symptoms.

CONCLUSIONS

MPH has greater effects than ATX on CPT measures of sustained attention in youth with ADHD. However, the dissociation of cognitive and behavioral change with treatment indicates that CPT measures cannot be considered proxies for symptomatic improvement. Further research on the dissociation of cognitive and behavioral endpoints for ADHD is indicated.

A review of OROS methylphenidate (Concerta(®)) in the treatment of attention-deficit/hyperactivity disorder

Attention-deficit/hyperactivity disorder (ADHD) is a common neurobehavioural disorder with onset during childhood. It affects a child's development, both at home and at school, and impacts on social, emotional and cognitive functioning, in both the home and the school environment. Untreated ADHD is very often associated with poor academic achievement, low occupational status, increased risk of substance abuse and delinquency. Current practice guidelines recommend a multimodal approach in the treatment of ADHD, which includes educational, behavioural and mental health interventions, and pharmacological management. Stimulant medications, including methylphenidate (MPH) and amphetamine products, are recommended as first-line pharmacotherapy in the treatment of ADHD. The choice of stimulant is influenced by several factors; the most influential factor is the duration of action. Long-acting medication provides benefits long after school and work. It also increases the likelihood of once-daily dosing, thereby eliminating the need for mid-day dosing, making the treatment more private, avoiding stigma and improving adherence to medication. MPH is the most widely used psychotropic medication in child psychiatry. It was first developed for use in children as an oral, immediate-release formulation and more recently as various extended-release formulations. These latter formulations include the 12 h preparation Concerta(®) (osmotic-release oral system [OROS] MPH), which utilizes an osmotic pump system, designed to overcome the difficulties of multiple daily dosing. Since it received approval from the US Food and Drug Administration in August 2000, OROS MPH has been quickly and widely accepted as one of the preferred treatments for ADHD because of its once-daily dosing. This paper reviews the data in support of long-acting OROS MPH in children, adolescents and adults, both in ADHD and in association with its comorbidities.

Traditional Chinese medicine in the treatment of ADHD: a review

This review covers an introduction of traditional Chinese medicine (TCM) in treating attention-deficit/hyperactivity disorder (ADHD), focusing on the traditional theoretic basis from the perspective of TCM regarding ADHD's cause, pathogenesis, methods of syndrome differentiation, and rationale for treatment. The authors present commonly accepted and successfully practiced clinical procedures used in China for diagnosis and treatment of ADHD by TCM clinicians along with the supportive clinical evidence. The authors hope to inspire more research to better understand the mechanisms underlying the therapies and to promote appropriate incorporation of TCM therapies with Western pharmacologic treatment to better help patients with ADHD.

Striatal volume deficits in children with ADHD who present a poor response to methylphenidate

Methylphenidate (MPH) is the first choice of medical treatment for attention-deficit/hyperactivity disorder (ADHD). Its mechanism of action is to inhibit the reuptake of dopamine and noradrenaline mainly in the region of the striatum. It has been estimated that 10-30 % of patients with ADHD do not respond adequately to MPH. The aim of this study was to evaluate whether striatal differences exist between good and poor responders to MPH. The sample included 27 treatment-naïve children with ADHD between the ages of 6 and 14. MPH administration started 1 day after the MRI acquisition. After a month, psychiatrists established the good or poor response to treatment according to clinical criteria. MRI images were analyzed using a technique based on regions of interest applied specifically to the caudate and accumbens nuclei. Sixteen patients showed good response to MPH and 11 a poor one. Regions of interest analysis showed that good responders had a higher concentration of gray matter in the head of both caudate nuclei and the right nucleus accumbens. Furthermore, a significant correlation was found between caudate and accumbens nuclei volume and the Conners' Parent Rating Scale and Continuous Performance Test improvement. These results support the hypothesis of the involvement of the caudate and accumbens nuclei in MPH response and in ADHD pathophysiology.

Executive function in adults with attention-deficit/hyperactivity disorder during treatment with atomoxetine in a randomized, placebo-controlled, withdrawal study

We assessed the executive function in adults with attention-deficit/hyperactivity disorder (ADHD) during atomoxetine treatment in a randomized withdrawal trial. Responders (Conners' ADHD Rating Scale-Investigator Rated: Screening Version [adult prompts] ≥30% reduction from baseline and Clinical Global Impression Scale-ADHD Severity score ≤3) to open-label atomoxetine (40-100 mg/d, 12 weeks) entered a 37-week double-blind maintenance period. Patients who maintained response (double-blind atomoxetine for 12 weeks) were randomized 1:1 to atomoxetine (80-100 mg/d, n = 266) or placebo (n = 258) for 25 weeks (total duration, 1 year). Patients and investigators were blinded to response criteria and randomization timing. Change in executive function was assessed with the Behavior Rating Inventory of Executive Function-Adult Version (BRIEF-A) Self-Report and Informant T scores from the randomization to the last-observation-carried-forward postrandomization week 25 (after week 17). Of the enrolled patients (n = 2017; mean age, 33.2 years; male, 58.7%), 524 responders were randomized. During open-label atomoxetine, subscales and individual items on both BRIEF-A questionnaires showed significant improvement (P < 0.001). After randomization, the following T scores improved significantly (P ≤ 0.05) with patients in the atomoxetine group versus those in the placebo group: global executive composite, behavioral regulation, and metacognition indices; plan/organize, working memory, inhibit, task monitor and shift (both BRIEF-A questionnaires), emotional control and organization of materials (BRIEF-A Informant), and initiate (BRIEF-A Self-Report). Atomoxetine significantly improved the executive function compared with placebo, which was maintained for 25 weeks or more; the executive function of patients in the placebo group worsened but did not return to baseline levels after randomization.

The effects of methylphenidate on whole brain intrinsic functional connectivity

Methylphenidate (MPH) is an indirect dopaminergic and noradrenergic agonist that is used to treat attention deficit hyperactivity disorder and that has shown therapeutic potential in neuropsychiatric diseases such as depression, dementia, and Parkinson's disease. While effects of MPH on task-induced brain activation have been investigated, little is known about how MPH influences the resting brain. To investigate the effects of 40 mg of oral MPH on intrinsic functional connectivity, we used resting state fMRI in 54 healthy male subjects in a double-blind, randomized, placebo-controlled study. Functional connectivity analysis employing ICA revealed seven resting state networks (RSN) of interest. Connectivity strength between the dorsal attention network and the thalamus was increased after MPH intake. Other RSN located in association cortex areas, such as the left and right frontoparietal networks and the executive control network, showed MPH-induced connectivity increase to sensory-motor and visual cortex regions and connectivity decrease to cortical and subcortical components of cortico-striato-thalamo-cortical circuits (CST). RSN located in sensory-motor cortex areas showed the opposite pattern with MPH-induced connectivity increase to CST components and connectivity decrease to sensory-motor and visual cortex regions. Our results provide evidence that MPH does not only alter intrinsic connectivity between brain areas involved in sustained attention, but that it also induces significant changes in the cortico-cortical and cortico-subcortical connectivity of many other cognitive and sensory-motor RSN.

Systematic review of atomoxetine data in childhood and adolescent attention-deficit hyperactivity disorder 2009-2011: focus on clinical efficacy and safety

BACKGROUND

Clinicians obtain critical prescribing knowledge from clinical papers and review articles. This is the first published systematic review of clinical atomoxetine data covering 2009-2011.

OBJECTIVE

We aim to update clinicians on current clinical atomoxetine data with specific reference to time of onset of efficacy and maximal efficacy. These data may allow critical analysis of comparative efficacy between atomoxetine and stimulant medications.

METHODS

A formal systematic review of atomoxetine data from January 2009-June 2011 was conducted. The search term used was "atomoxetine" in the English language. The search yielded 747 citations from which 106 are clinical data. This paper includes clinical efficacy and safety data and excludes quality-of-life and review papers.

RESULTS

Atomoxetine has an onset of action within 4 weeks (possibly within 1 week in subsequent responders) but requires at least 12 weeks for full response to be demonstrated. Treatment-naïve cohorts (6-12 weeks) report effect sizes of 0.6-1.3. Using minimum 6-week clinical trial criteria, atomoxetine may demonstrate similar efficacy to methylphenidate comparing reduction in core ADHD symptoms in meta-analysis, although the diversity of the data makes interpretation complex. From epidemiological databases, cardiovascular and suicide-related events were similar to those seen in patients taking methylphenidate.

CONCLUSIONS

Incremental response time to atomoxetine should be considered in the design of future comparative efficacy trials.

Psychostimulants and cognition: a continuum of behavioral and cognitive activation

Psychostimulants such as cocaine have been used as performance enhancers throughout recorded history. Although psychostimulants are commonly prescribed to improve attention and cognition, a great deal of literature has described their ability to induce cognitive deficits, as well as addiction. How can a single drug class be known to produce both cognitive enhancement and impairment? Properties of the particular stimulant drug itself and individual differences between users have both been suggested to dictate the outcome of stimulant use. A more parsimonious alternative, which we endorse, is that dose is the critical determining factor in cognitive effects of stimulant drugs. Herein, we review several popular stimulants (cocaine, amphetamine, methylphenidate, modafinil, and caffeine), outlining their history of use, mechanism of action, and use and abuse today. One common graphic depiction of the cognitive effects of psychostimulants is an inverted U-shaped dose-effect curve. Moderate arousal is beneficial to cognition, whereas too much activation leads to cognitive impairment. In parallel to this schematic, we propose a continuum of psychostimulant activation that covers the transition from one drug effect to another as stimulant intake is increased. Low doses of stimulants effect increased arousal, attention, and cognitive enhancement; moderate doses can lead to feelings of euphoria and power, as well as addiction and cognitive impairment; and very high doses lead to psychosis and circulatory collapse. This continuum helps account for the seemingly disparate effects of stimulant drugs, with the same drug being associated with cognitive enhancement and impairment.

Osmotic release oral system-methylphenidate improves neural activity during low reward processing in children and adolescents with attention-deficit/hyperactivity disorder

Attention-deficit/hyperactivity disorder (ADHD) is neurobehavioral disorder characterized by inattention, hyperactivity/impulsivity and impaired reward system function, such as delay aversion and low reward sensitivity. The pharmacological treatment for ADHD includes methylphenidate (MPH), or osmotic release oral system-MPH (OROS-MPH), which increases extrasynaptic dopamine and noradrenaline levels by blocking their reuptake. Although previous functional magnetic resonance imaging (fMRI) studies revealed that acute treatment with MPH alters activation of the nucleus accumbens during delay aversion in children and adolescents with ADHD, the effects a relatively long period of OROS-MPH treatment on delay aversion as well as reward sensitivity remain unclear. Thus, we evaluated brain activation with fMRI during a reward sensitivity paradigm that consists of high monetary reward and low monetary reward conditions before and after a 3-month treatment with OROS-MPH in 17 children and adolescents with ADHD (mean age, 13.3 ± 2.2) and 17 age- and sex-matched healthy controls (mean age, 13.0 ± 1.9). We found that before treatment there was decreased activation of the nucleus accumbens and thalamus in patients with ADHD during only the low monetary reward condition, which was improved to same level as those of the healthy controls after the treatment. The observed change in brain activity was associated with improved ADHD symptom scores, which were derived from Japanese versions of the ADHD rating scale-IV. These results suggest that treatment with OROS-MPH for a relatively long period is effective in controlling reward sensitivity in children and adolescents with ADHD.

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Attention deficit/hyperactivity disorder (ADHD) has low reward sensitivity.

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Activity in thalamus and nucleus accumbens was decreased in low monetary reward.

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Osmotic release oral system-methylphenidate (OROS-MPH) is a medication for ADHD.

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Brain activity and ADHD symptoms were improved by 3-month treatment with OROS-MPH.

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OROS-MPH treatment for long periods may change brain activity of pediatric ADHD.

Performance on a strategy set shifting task during adolescence in a genetic model of attention deficit/hyperactivity disorder: methylphenidate vs. atomoxetine treatments

Research examining medication effects on set shifting in teens with attention deficit/hyperactivity disorder (ADHD) is lacking. An animal model of ADHD may be useful for exploring this gap. The spontaneously hypertensive rat (SHR) is a commonly used animal model of ADHD. SHR and two comparator strains, Wistar-Kyoto (WKY) and Wistar (WIS), were evaluated during adolescence in a strategy set shifting task under conditions of a 0s or 15s delay to reinforcer delivery. The task had three phases: initial discrimination, set shift and reversal learning. Under 0s delays, SHR performed as well as or better than WKY and WIS. Treatment with 0.3mg/kg/day atomoxetine had little effect, other than to modestly increase trials to criterion during set shifting in all strains. Under 15s delays, SHR had longer lever press reaction times, longer latencies to criterion and more trial omissions than WKY during set shifting and reversal learning. These deficits were not reduced systematically by 1.5mg/kg/day methylphenidate or 0.3mg/kg/day atomoxetine. Regarding learning in SHR, methylphenidate improved initial discrimination, whereas atomoxetine improved set shifting but disrupted initial discrimination. During reversal learning, both drugs were ineffective in SHR, and atomoxetine made reaction time and trial omissions greater in WKY. Overall, WIS performance differed from SHR or WKY, depending on phase. Collectively, a genetic model of ADHD in adolescent rats revealed that neither methylphenidate nor atomoxetine mitigated all deficits in SHR during the set shifting task. Thus, methylphenidate or atomoxetine monotherapy may not mitigate all set shift task-related deficits in teens with ADHD.

Interventions for executive function deficits in children and adolescents

For children with neurodevelopmental or acquired disorders, deficits in executive function (EF) processes (i.e., attention, working memory, cognitive flexibility, and problem solving), are often evident. Moreover, EF deficits are associated with academic difficulties, behavioral and social difficulties, and long-term psychological maladjustment rendering prevention and intervention of EF deficits an important consideration. Many methods exist to address EF processes; this review will focus on pharmacological, cognitive/metacognitive, computerized, and neurofeedback approaches. Across research reviewed, results tend to vary depending on age, disorder, comorbid conditions, and outcome measures. Notably, there is limited research to suggest long-term maintenance of changes in symptom presentation, improved developmental trajectory, normalization of EF processes, or alteration to the associated neural connections. Implications for practice and future research for evidence-based interventions to address EF are discussed.

ADHD treatments, sleep, and sleep problems: complex associations

ADHD, sleep, and ADHD treatments are highly interrelated. In this review, we describe the effects of stimulants and non stimulant medications on sleep in children, adolescents, and adults with ADHD. Clinical predictors of sleep problems during pharmacotherapy include age, sleep problems prior to initiating treatment, and dose and dosing schedule. As yet, we have little understanding of the biological or genetic factors related to individual variation in drug response and sleep.

A liquid chromatography/tandem mass spectrometry assay for the analysis of atomoxetine in human plasma and in vitro cellular samples

A simple, rapid and sensitive method for quantification of atomoxetine by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed. This assay represents the first LC-MS/MS quantification method for atomoxetine utilizing electrospray ionization. Deuterated atomoxetine (d3-atomoxetine) was adopted as the internal standard. Direct protein precipitation was utilized for sample preparation. This method was validated for both human plasma and in vitro cellular samples. The lower limit of quantification was 3 ng/mL and 10 nm for human plasma and cellular samples, respectively. The calibration curves were linear within the ranges of 3-900 ng/mL and 10 nm to 10 µm for human plasma and cellular samples, respectively (r(2)  >0.999). The intra- and inter-day assay accuracy and precision were evaluated using quality control samples at three different concentrations in both human plasma and cellular lysate. Sample run stability, assay selectivity, matrix effect and recovery were also successfully demonstrated. The present assay is superior to previously published LC-MS and LC-MS/MS methods in terms of sensitivity or the simplicity of sample preparation. This assay is applicable to the analysis of atomoxetine in both human plasma and in vitro cellular samples.

Efficacy and Safety of Atomoxetine in the Treatment of Children and Adolescents with Attention Deficit Hyperactivity Disorder

Several non-stimulant medications have been used in the treatment of attention deficit hyperactivity disorder (ADHD). Atomoxetine, was introduced in 2002. The safety and efficacy of atomoxetine in the treatment of ADHD for children, adolescents, and adults has been evaluated in over 4000 patients in randomized controlled studies and double blinded studies as well as in recent large longitudinal studies. This paper provides an updated summary of the literature on atomoxetine, particularly in relation to findings on the short- and long-term safety of atomoxetine in children and adolescents arising from recent large longitudinal cohort studies. Information is presented about the efficacy, safety, and tolerability of this medication.

Comparative efficacy and acceptability of methylphenidate and atomoxetine in treatment of attention deficit hyperactivity disorder in children and adolescents: a meta-analysis

BACKGROUND

Psychostimulants and non stimulants are effective in the treatment of ADHD. Efficacy of both methylphenidate and atomoxetine has been established in placebo controlled trials. Direct comparison of efficacy is now possible due to availability of results from several head-to-head trials of these two medications.

METHODS

All published, randomized, open label or double blind trials, comparing efficacy of methylphenidate with atomoxetine, in treatment of ADHD in children, diagnosed using DSM-IV™ criteria were included. The outcome studied was ADHDRS-IVParent:Inv score. The standardized mean difference (SMD) was used as a measure of effect size.

RESULTS

Nine randomized trials comparing methylphenidate and atomoxetine, with a total of 2762 participants were included. Meta-analysis did not find a significant difference in efficacy between methylphenidate and atomoxetine (SMD=0.09, 95% CI -0.08-0.26) (Z=1.06, p=0.29). Synthesis of data from eight trials found no significant difference in response rates (RR=0.93 95% CI 0.76-1.14, p=0.49). Sub group analysis showed a significant standardized mean difference favouring OROS methylphenidate (SMD=0.32, 95% CI 0.12-0.53 (Z=3.05, p<0.002). Immediate release methylphenidate was not superior to atomoxetine (SMD=-0.04, 95% CI -0.19-0.12) (Z=0.46, p=0.64). Excluding open label trials did not significantly alter the effect size (SMD=0.08, 95% CI -0.04-0.21) (Z=1.27, p=0.20). All-cause discontinuation was used as a measure of acceptability. There was no significant difference in all cause discontinuation between atomoxetine and methylphenidate (RR 1.22, 95% CI 0.87-1.71). There was significant heterogeneity among the studies (p=0.002, I2=67%). Subgroup analysis demonstrated the heterogeneity to be due to the open label trials (p=0.001, I2=81%).

CONCLUSIONS

In general atomoxetine and methylphenidate have comparable efficacy and equal acceptability in treatment of ADHD in children and adolescents. However OROS methylphenidate is more effective than atomoxetine and may be considered as first line treatment in treatment of ADHD in children and adolescents.