A randomized, double-blind, multicenter, parallel-group, placebo-controlled, dose-optimization study of the methylphenidate transdermal system for the treatment of ADHD in adolescents

Methylphenidate for children and adolescents with attention deficit hyperactivity disorder (ADHD)

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) is one of the most commonly diagnosed and treated psychiatric disorders in childhood. Typically, children and adolescents with ADHD find it difficult to pay attention and they are hyperactive and impulsive. Methylphenidate is the psychostimulant most often prescribed, but the evidence on benefits and harms is uncertain. This is an update of our comprehensive systematic review on benefits and harms published in 2015.

OBJECTIVES

To assess the beneficial and harmful effects of methylphenidate for children and adolescents with ADHD.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, three other databases and two trials registers up to March 2022. In addition, we checked reference lists and requested published and unpublished data from manufacturers of methylphenidate.

SELECTION CRITERIA

We included all randomised clinical trials (RCTs) comparing methylphenidate versus placebo or no intervention in children and adolescents aged 18 years and younger with a diagnosis of ADHD. The search was not limited by publication year or language, but trial inclusion required that 75% or more of participants had a normal intellectual quotient (IQ > 70). We assessed two primary outcomes, ADHD symptoms and serious adverse events, and three secondary outcomes, adverse events considered non-serious, general behaviour, and quality of life.

DATA COLLECTION AND ANALYSIS

Two review authors independently conducted data extraction and risk of bias assessment for each trial. Six review authors including two review authors from the original publication participated in the update in 2022. We used standard Cochrane methodological procedures. Data from parallel-group trials and first-period data from cross-over trials formed the basis of our primary analyses. We undertook separate analyses using end-of-last period data from cross-over trials. We used Trial Sequential Analyses (TSA) to control for type I (5%) and type II (20%) errors, and we assessed and downgraded evidence according to the GRADE approach.

MAIN RESULTS

We included 212 trials (16,302 participants randomised); 55 parallel-group trials (8104 participants randomised), and 156 cross-over trials (8033 participants randomised) as well as one trial with a parallel phase (114 participants randomised) and a cross-over phase (165 participants randomised). The mean age of participants was 9.8 years ranging from 3 to 18 years (two trials from 3 to 21 years). The male-female ratio was 3:1. Most trials were carried out in high-income countries, and 86/212 included trials (41%) were funded or partly funded by the pharmaceutical industry. Methylphenidate treatment duration ranged from 1 to 425 days, with a mean duration of 28.8 days. Trials compared methylphenidate with placebo (200 trials) and with no intervention (12 trials). Only 165/212 trials included usable data on one or more outcomes from 14,271 participants. Of the 212 trials, we assessed 191 at high risk of bias and 21 at low risk of bias. If, however, deblinding of methylphenidate due to typical adverse events is considered, then all 212 trials were at high risk of bias.

PRIMARY OUTCOMES

methylphenidate versus placebo or no intervention may improve teacher-rated ADHD symptoms (standardised mean difference (SMD) -0.74, 95% confidence interval (CI) -0.88 to -0.61; I² = 38%; 21 trials; 1728 participants; very low-certainty evidence). This corresponds to a mean difference (MD) of -10.58 (95% CI -12.58 to -8.72) on the ADHD Rating Scale (ADHD-RS; range 0 to 72 points). The minimal clinically relevant difference is considered to be a change of 6.6 points on the ADHD-RS. Methylphenidate may not affect serious adverse events (risk ratio (RR) 0.80, 95% CI 0.39 to 1.67; I² = 0%; 26 trials, 3673 participants; very low-certainty evidence). The TSA-adjusted intervention effect was RR 0.91 (CI 0.31 to 2.68).

SECONDARY OUTCOMES

methylphenidate may cause more adverse events considered non-serious versus placebo or no intervention (RR 1.23, 95% CI 1.11 to 1.37; I² = 72%; 35 trials 5342 participants; very low-certainty evidence). The TSA-adjusted intervention effect was RR 1.22 (CI 1.08 to 1.43). Methylphenidate may improve teacher-rated general behaviour versus placebo (SMD -0.62, 95% CI -0.91 to -0.33; I² = 68%; 7 trials 792 participants; very low-certainty evidence), but may not affect quality of life (SMD 0.40, 95% CI -0.03 to 0.83; I² = 81%; 4 trials, 608 participants; very low-certainty evidence).

AUTHORS' CONCLUSIONS

The majority of our conclusions from the 2015 version of this review still apply. Our updated meta-analyses suggest that methylphenidate versus placebo or no-intervention may improve teacher-rated ADHD symptoms and general behaviour in children and adolescents with ADHD. There may be no effects on serious adverse events and quality of life. Methylphenidate may be associated with an increased risk of adverse events considered non-serious, such as sleep problems and decreased appetite. However, the certainty of the evidence for all outcomes is very low and therefore the true magnitude of effects remain unclear. Due to the frequency of non-serious adverse events associated with methylphenidate, the blinding of participants and outcome assessors is particularly challenging. To accommodate this challenge, an active placebo should be sought and utilised. It may be difficult to find such a drug, but identifying a substance that could mimic the easily recognised adverse effects of methylphenidate would avert the unblinding that detrimentally affects current randomised trials. Future systematic reviews should investigate the subgroups of patients with ADHD that may benefit most and least from methylphenidate. This could be done with individual participant data to investigate predictors and modifiers like age, comorbidity, and ADHD subtypes.

Treatment of Adolescents with Concurrent Substance Use Disorder and Attention-Deficit/Hyperactivity Disorder: A Systematic Review

Childhood attention-deficit/hyperactivity disorder (ADHD) is a risk factor for the development of substance abuse and substance use disorders (SUD) in adolescence and (early) adulthood. ADHD and SUD also frequently co-occur in treatment-seeking adolescents, which complicates diagnosis and treatment, and is associated with poor treatment outcomes. In this study, we provide a systematic review of controlled studies on the effectiveness of pharmacological, psychosocial, and complementary treatments of ADHD in adolescents with and without comorbid SUD. In addition, we review the longitudinal association between pharmacotherapy for childhood ADHD and the development of SUD in adolescence and early adulthood. We conducted a systematic review of the research literature published since 2000 using Medline, PsycINFO, and the Cochrane Database of Systematic Reviews databases to select randomized clinical trials, observational studies, and meta-analyses. The quality of the evidence from each study was rated using the SIGN grading system. Based on the limited evidence available, strong clinical recommendations are not justified, but provisionally, we conclude that stimulant treatment in children with ADHD may prevent the development of SUD in adolescence or young adulthood, that high-dose stimulant treatment could be an effective treatment for adolescents with ADHD and SUD comorbidity, that cognitive behavior therapy might have a small beneficial effect in these patients, and that alternative treatments are probably not effective. More studies are needed to draw definitive conclusions that will allow for strong clinical recommendations.

[International Consensus Statement for the Screening, Diagnosis, and Treatment of Adolescents with Concurrent Attention-Deficit/Hyperactivity Disorder and Substance Use Disorder]

International Consensus Statement for the Screening, Diagnosis, and Treatment of Adolescents with Concurrent Attention-Deficit/Hyperactivity Disorder and Substance Use Disorder Abstract. Background: Childhood attention-deficit/hyperactivity disorder (ADHD) is a risk factor for substance misuse and substance use disorder (SUD) in adolescence and (early) adulthood. ADHD and SUD also frequently co-occur in treatment-seeking adolescents, which complicates diagnosis and treatment and is associated with poor treatment outcomes. Research on the effect of treatment of childhood ADHD on the prevention of adolescent SUD is inconclusive, and studies on the diagnosis and treatment of adolescents with ADHD and SUD are scarce. Thus, the available evidence is generally not sufficient to justify robust treatment recommendations. Objective: The aim of the study was to obtain a consensus statement based on a combination of scientific data and clinical experience. Method: A modified Delphi study to reach consensus based upon the combination of scientific data and clinical experience with a multidisciplinary group of 55 experts from 17 countries. The experts were asked to rate a set of statements on the effect of treatment of childhood ADHD on adolescent SUD and on the screening, diagnosis, and treatment of adolescents with comorbid ADHD and SUD. Results: After 3 iterative rounds of rating and adapting 37 statements, consensus was reached on 36 of these statements representing 6 domains: general (n = 4), risk of developing SUD (n = 3), screening and diagnosis (n = 7), psychosocial treatment (n = 5), pharmacological treatment (n = 11), and complementary treatments (n = 7). Routine screening is recommended for ADHD in adolescent patients in substance abuse treatment and for SUD in adolescent patients with ADHD in mental healthcare settings. Long-acting stimulants are recommended as the first-line treatment of ADHD in adolescents with concurrent ADHD and SUD, and pharmacotherapy should preferably be embedded in psychosocial treatment. The only remaining no-consensus statement concerned the requirement of abstinence before starting pharmacological treatment in adolescents with ADHD and concurrent SUD. In contrast to the majority, some experts required full abstinence before starting any pharmacological treatment, some were against the use of stimulants in the treatment of these patients (independent of abstinence), while some were against the alternative use of bupropion. Conclusion: This international consensus statement can be used by clinicians and patients together in a shared decision-making process to select the best interventions and to reach optimal outcomes in adolescent patients with concurrent ADHD and SUD.

Systematic review of transdermal treatment options in attention-deficit/hyperactivity disorder: implications for use in adult patients

BACKGROUND

Adults with attention-deficit/hyperactivity disorder (ADHD) often face delays in diagnosis and remain untreated, despite significant negative impacts. To evaluate the safety and efficacy of transdermal treatment options in children, adolescents, and adults, a systematic literature review was conducted, with a focus on the implications of transdermal therapies for ADHD in adults.

METHODS

A MEDLINE/Embase/BIOSIS/SCOPUS database search was conducted December 4, 2019, for English-language articles of interventional clinical trials using transdermal formulations for the treatment of ADHD without publication date limit. Assessed outcomes included efficacy, safety, adherence, abuse potential, cost efficacy, and health-related quality of life.

RESULTS

Of 23 eligible publications, 18 were in children or adolescents (n = 1699; range 23-305), and 5 in adults (n = 274; range 14-90); all included methylphenidate transdermal system (MTS). All seven pediatric publications reporting change in ADHD symptomology from baseline reported a significant improvement with MTS treatment. Similarly, in three adult publications, ADHD symptoms improved significantly with MTS treatment. Safety findings in pediatric and adult studies were comparable; the most frequently reported treatment-emergent adverse events (TEAEs), namely, headache, decreased appetite, and insomnia, were reported in 13/16 (81%) of publications reporting specific TEAEs. MTS-related dermal reactions were mostly mild and transient. Discontinuation due to dermal reactions was reported in 10 studies (range 0%-7.1% [1 of 14 patients]). MTS compliance was high when assessed (97%-99%).

CONCLUSIONS

Transdermal therapies provide a useful treatment formulation for ADHD. Studies of MTS and other transdermal formulations, such as amphetamine, in adult patients are needed in this underserved population.

International Consensus Statement for the Screening, Diagnosis, and Treatment of Adolescents with Concurrent Attention-Deficit/Hyperactivity Disorder and Substance Use Disorder

BACKGROUND

Childhood attention-deficit/hyperactivity disorder (ADHD) is a risk factor for substance misuse and substance use disorder (SUD) in adolescence and (early) adulthood. ADHD and SUD also frequently co-occur in treatment-seeking adolescents, which complicates diagnosis and treatment and is associated with poor treatment outcomes. Research on the effect of treatment of childhood ADHD on the prevention of adolescent SUD is inconclusive, and studies on the diagnosis and treatment of adolescents with ADHD and SUD are scarce. Thus, the available evidence is generally not sufficient to justify robust treatment recommendations.

OBJECTIVE

The aim of the study was to obtain a consensus statement based on a combination of scientific data and clinical experience.

METHOD

A modified Delphi study to reach consensus based upon the combination of scientific data and clinical experience with a multidisciplinary group of 55 experts from 17 countries. The experts were asked to rate a set of statements on the effect of treatment of childhood ADHD on adolescent SUD and on the screening, diagnosis, and treatment of adolescents with comorbid ADHD and SUD.

RESULTS

After 3 iterative rounds of rating and adapting 37 statements, consensus was reached on 36 of these statements representing 6 domains: general (n = 4), risk of developing SUD (n = 3), screening and diagnosis (n = 7), psychosocial treatment (n = 5), pharmacological treatment (n = 11), and complementary treatments (n = 7). Routine screening is recommended for ADHD in adolescent patients in substance abuse treatment and for SUD in adolescent patients with ADHD in mental healthcare settings. Long-acting stimulants are recommended as the first-line treatment of ADHD in adolescents with concurrent ADHD and SUD, and pharmacotherapy should preferably be embedded in psychosocial treatment. The only remaining no-consensus statement concerned the requirement of abstinence before starting pharmacological treatment in adolescents with ADHD and concurrent SUD. In contrast to the majority, some experts required full abstinence before starting any pharmacological treatment, some were against the use of stimulants in the treatment of these patients (independent of abstinence), while some were against the alternative use of bupropion.

CONCLUSION

This international consensus statement can be used by clinicians and patients together in a shared decision-making process to select the best interventions and to reach optimal outcomes in adolescent patients with concurrent ADHD and SUD.

Sleep-Associated Adverse Events During Methylphenidate Treatment of Attention-Deficit/Hyperactivity Disorder: A Meta-Analysis

OBJECTIVE

Sleep disturbances are a feature of attention-deficit/hyperactivity disorder (ADHD) and an adverse event (AE) of methylphenidate treatment. The authors sought to clarify methylphenidate-associated sleep problems and how studies are affected by confounding factors.

DATA SOURCES

Published studies in English collected via online databases and unpublished data from www.clinicaltrials.gov and US Food and Drug Administration websites. Sources were searched from inception to August 2017.

STUDY SELECTION

Included were blinded placebo-controlled studies of youth with ADHD conducted in naturalistic settings, leading to 35 studies yielding 75 observations of sleep-related AEs. These studies comprised 3,079 drug-exposed and 2,606 placebo-treated patients.

DATA EXTRACTION

Two PhD-level reviewers reviewed each study for inclusion. Four PhD/PharmD-level reviewers extracted data in duplicate. Discrepancies were resolved by discussion or, if needed, by the senior author.

RESULTS

Increased pooled relative risks (RRs) were found for methylphenidate-associated sleep-related AEs for insomnia (general), initial insomnia, middle insomnia, combined insomnia, and sleep disorder. Several sample or study design features were significantly associated with the RR for sleep-related AEs and the methylphenidate formulation studied (P < .05). After correction for confounding variables, significant differences among drugs were found for initial insomnia, insomnia (general), and sleep disorder (P < .0001) as the other categories could not be tested due to insufficient studies. The findings also show that the RR and its interpretation are constrained by the placebo AE rate.

CONCLUSIONS

Several types of insomnia and sleep problems are associated with methylphenidate treatment. Study design and sample features influence the RR statistic. By showing that the rate of placebo AEs impacts the RR, this study provides the field with a useful covariate for adjusting RR statistics.

The Effects of Long-Acting Stimulant and Nonstimulant Medications in Children and Adolescents with Attention-Deficit/Hyperactivity Disorder: A Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

The aim of this study was to assess the efficacy and safety of stimulant and nonstimulant medications in children and adolescents using as an outcome measure the Attention-Deficit/Hyperactivity Disorder Rating Scale-IV (ADHD-RS-IV), and to examine the effect of medications in different ADHD subtypes (i.e., inattention and hyperactivity/impulsivity).

METHODS

MEDLINE, Scopus, EMBASE, EBSCO (E-journal, CINAHL and SportDiscus), PUBMED, and The Cochrane Central Register of Controlled Trials databases were searched. Randomized controlled trials (RCTs) with parallel group or placebo-controlled studies comparing the effect of medications (stimulants or nonstimulants) in children and adolescents with ADHD were included. The main outcomes were the ADHD-RS-IV total score and subtypes (inattention and hyperactivity/impulsivity). Treatment-emergent adverse events (TEAEs) and secondary outcomes such as systolic and diastolic blood pressure, and pulse rate were considered.

RESULTS

The search strategy identified 15 RCTs, including a total of 4648 children and/or adolescents diagnosed with ADHD aged 6 to 17 years old. Overall, both stimulant and nonstimulant medications reduce the ADHD-RS-IV score with a standardized mean difference (SMD) of -0.70 (confidence interval [95% CI], -0.85 to -0.55); in subgroup analyses, the SMD was -0.83 (95% CI, -1.11 to -0.54) for stimulant medications and -0.58 (95% CI, -0.69 to -0.46) for nonstimulant medications. Similar results were observed in inattention and hyperactivity/impulsivity subtypes. The placebo group also showed a medium effect SMD of -0.68 (95% CI, -0.82 to -0.54). The most frequent TEAEs for stimulant and nonstimulant medications, respectively, were decreased appetite (28.6% and 14.2%) and somnolence (4.4% and 34.1%).

CONCLUSIONS

These results suggest that both stimulant and nonstimulant medications mitigate ADHD symptoms in children and adolescents, although subgroup analyses suggest a greater effectiveness of stimulant medications.

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.

Dietary, Nutrient Patterns and Blood Essential Elements in Chinese Children with ADHD

Dietary or nutrient patterns represent the combined effects of foods or nutrients, and elucidate efficaciously the impact of diet on diseases. Because the pharmacotherapy on attention deficit hyperactivity disorder (ADHD) was reported be associated with certain side effects, and the etiology of ADHD is multifactorial, this study investigated the association of dietary and nutrient patterns with the risk of ADHD. We conducted a case-control study with 592 Chinese children including ADHD (n = 296) and non-ADHD (n = 296) aged 6–14 years old, matched by age and sex. Dietary and nutrient patterns were identified using factor analysis and a food frequency questionnaire. Blood essential elements levels were measured using atomic absorption spectrometry. A fish-white meat dietary pattern rich in shellfish, deep water fish, white meat, freshwater fish, organ meat and fungi and algae was inversely associated with ADHD (p = 0.006). Further analysis found that a mineral-protein nutrient pattern rich in zinc, protein, phosphorus, selenium, calcium and riboflavin was inversely associated with ADHD (p = 0.014). Additionally, the blood zinc was also negatively related to ADHD (p = 0.003). In conclusion, the fish-white meat dietary pattern and mineral-protein nutrient pattern may have beneficial effects on ADHD in Chinese children, and blood zinc may be helpful in distinguishing ADHD in Chinese children.

Methylphenidate for children and adolescents with attention deficit hyperactivity disorder (ADHD)

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) is one of the most commonly diagnosed and treated psychiatric disorders in childhood. Typically, children with ADHD find it difficult to pay attention, they are hyperactive and impulsive.Methylphenidate is the drug most often prescribed to treat children and adolescents with ADHD but, despite its widespread use, this is the first comprehensive systematic review of its benefits and harms.

OBJECTIVES

To assess the beneficial and harmful effects of methylphenidate for children and adolescents with ADHD.

SEARCH METHODS

In February 2015 we searched six databases (CENTRAL, Ovid MEDLINE, EMBASE, CINAHL, PsycINFO, Conference Proceedings Citations Index), and two trials registers. We checked for additional trials in the reference lists of relevant reviews and included trials. We contacted the pharmaceutical companies that manufacture methylphenidate to request published and unpublished data.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) comparing methylphenidate versus placebo or no intervention in children and adolescents aged 18 years and younger with a diagnosis of ADHD. At least 75% of participants needed to have an intellectual quotient of at least 70 (i.e. normal intellectual functioning). Outcomes assessed included ADHD symptoms, serious adverse events, non-serious adverse events, general behaviour and quality of life.

DATA COLLECTION AND ANALYSIS

Seventeen review authors participated in data extraction and risk of bias assessment, and two review authors independently performed all tasks. We used standard methodological procedures expected within Cochrane. Data from parallel-group trials and first period data from cross-over trials formed the basis of our primary analyses; separate analyses were undertaken using post-cross-over data from cross-over trials. We used Trial Sequential Analyses to control for type I (5%) and type II (20%) errors, and we assessed and downgraded evidence according to the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach for high risk of bias, imprecision, indirectness, heterogeneity and publication bias.

MAIN RESULTS

The studies.We included 38 parallel-group trials (5111 participants randomised) and 147 cross-over trials (7134 participants randomised). Participants included individuals of both sexes, at a boys-to-girls ratio of 5:1, and participants' ages ranged from 3 to 18 years across most studies (in two studies ages ranged from 3 to 21 years). The average age across all studies was 9.7 years. Most participants were from high-income countries.The duration of methylphenidate treatment ranged from 1 to 425 days, with an average duration of 75 days. Methylphenidate was compared to placebo (175 trials) or no intervention (10 trials). Risk of Bias.All 185 trials were assessed to be at high risk of bias. Primary outcomes. Methylphenidate may improve teacher-rated ADHD symptoms (standardised mean difference (SMD) -0.77, 95% confidence interval (CI) -0.90 to -0.64; 19 trials, 1698 participants; very low-quality evidence). This corresponds to a mean difference (MD) of -9.6 points (95% CI -13.75 to -6.38) on the ADHD Rating Scale (ADHD-RS; range 0 to 72 points; DuPaul 1991a). A change of 6.6 points on the ADHD-RS is considered clinically to represent the minimal relevant difference. There was no evidence that methylphenidate was associated with an increase in serious (e.g. life threatening) adverse events (risk ratio (RR) 0.98, 95% CI 0.44 to 2.22; 9 trials, 1532 participants; very low-quality evidence). The Trial Sequential Analysis-adjusted intervention effect was RR 0.91 (CI 0.02 to 33.2).

SECONDARY OUTCOMES

Among those prescribed methylphenidate, 526 per 1000 (range 448 to 615) experienced non-serious adverse events, compared with 408 per 1000 in the control group. This equates to a 29% increase in the overall risk of any non-serious adverse events (RR 1.29, 95% CI 1.10 to 1.51; 21 trials, 3132 participants; very low-quality evidence). The Trial Sequential Analysis-adjusted intervention effect was RR 1.29 (CI 1.06 to 1.56). The most common non-serious adverse events were sleep problems and decreased appetite. Children in the methylphenidate group were at 60% greater risk for trouble sleeping/sleep problems (RR 1.60, 95% CI 1.15 to 2.23; 13 trials, 2416 participants), and 266% greater risk for decreased appetite (RR 3.66, 95% CI 2.56 to 5.23; 16 trials, 2962 participants) than children in the control group.Teacher-rated general behaviour seemed to improve with methylphenidate (SMD -0.87, 95% CI -1.04 to -0.71; 5 trials, 668 participants; very low-quality evidence).A change of seven points on the Child Health Questionnaire (CHQ; range 0 to 100 points; Landgraf 1998) has been deemed a minimal clinically relevant difference. The change reported in a meta-analysis of three trials corresponds to a MD of 8.0 points (95% CI 5.49 to 10.46) on the CHQ, which suggests that methylphenidate may improve parent-reported quality of life (SMD 0.61, 95% CI 0.42 to 0.80; 3 trials, 514 participants; very low-quality evidence).

AUTHORS' CONCLUSIONS

The results of meta-analyses suggest that methylphenidate may improve teacher-reported ADHD symptoms, teacher-reported general behaviour, and parent-reported quality of life among children and adolescents diagnosed with ADHD. However, the low quality of the underpinning evidence means that we cannot be certain of the magnitude of the effects. Within the short follow-up periods typical of the included trials, there is some evidence that methylphenidate is associated with increased risk of non-serious adverse events, such as sleep problems and decreased appetite, but no evidence that it increases risk of serious adverse events.Better designed trials are needed to assess the benefits of methylphenidate. Given the frequency of non-serious adverse events associated with methylphenidate, the particular difficulties for blinding of participants and outcome assessors point to the advantage of large, 'nocebo tablet' controlled trials. These use a placebo-like substance that causes adverse events in the control arm that are comparable to those associated with methylphenidate. However, for ethical reasons, such trials should first be conducted with adults, who can give their informed consent.Future trials should publish depersonalised individual participant data and report all outcomes, including adverse events. This will enable researchers conducting systematic reviews to assess differences between intervention effects according to age, sex, comorbidity, type of ADHD and dose. Finally, the findings highlight the urgent need for large RCTs of non-pharmacological treatments.

A randomized, placebo-controlled, double-blind study of sapropterin to treat ADHD symptoms and executive function impairment in children and adults with sapropterin-responsive phenylketonuria

Symptoms of attention deficit-hyperactivity disorder (ADHD), particularly inattention, and impairments in executive functioning have been reported in early and continuously treated children, adolescents, and adults with phenylketonuria (PKU). In addition, higher blood phenylalanine (Phe) levels have been correlated with the presence of ADHD symptoms and executive functioning impairment. The placebo-controlled PKU ASCEND study evaluated the effects of sapropterin therapy on PKU-associated symptoms of ADHD and executive and global functioning in individuals who had a therapeutic blood Phe response to sapropterin therapy. The presence of ADHD inattentive symptoms and executive functioning deficits was confirmed in this large cohort of 206 children and adults with PKU, of whom 118 responded to sapropterin therapy. In the 38 individuals with sapropterin-responsive PKU and ADHD symptoms at baseline, sapropterin therapy resulted in a significant improvement in ADHD inattentive symptoms in the first 4 weeks of treatment, and improvements were maintained throughout the 26 weeks of treatment. Sapropterin was well-tolerated with a favorable safety profile. The improvements in ADHD inattentive symptoms and aspects of executive functioning in response to sapropterin therapy noted in a large cohort of individuals with PKU indicate that these symptoms are potentially reversible when blood Phe levels are reduced.

Premarket safety and efficacy studies for ADHD medications in children

BACKGROUND

Attention-deficit hyperactivity disorder (ADHD) is a chronic condition and pharmacotherapy is the mainstay of treatment, with a variety of ADHD medications available to patients. However, it is unclear to what extent the long-term safety and efficacy of ADHD drugs have been evaluated prior to their market authorization. We aimed to quantify the number of participants studied and their length of exposure in ADHD drug trials prior to marketing.

METHODS

We identified all ADHD medications approved by the Food and Drug Administration (FDA) and extracted data on clinical trials performed by the sponsor and used by the FDA to evaluate the drug's clinical efficacy and safety. For each ADHD medication, we measured the total number of participants studied and the length of participant exposure and identified any FDA requests for post-marketing trials.

RESULTS

A total of 32 clinical trials were conducted for the approval of 20 ADHD drugs. The median number of participants studied per drug was 75 (IQR 0, 419). Eleven drugs (55%) were approved after <100 participants were studied and 14 (70%) after <300 participants. The median trial length prior to approval was 4 weeks (IQR 2, 9), with 5 (38%) drugs approved after participants were studied <4 weeks and 10 (77%) after <6 months. Six drugs were approved with requests for specific additional post-marketing trials, of which 2 were performed.

CONCLUSIONS

Clinical trials conducted for the approval of many ADHD drugs have not been designed to assess rare adverse events or long-term safety and efficacy. While post-marketing studies can fill in some of the gaps, better assurance is needed that the proper trials are conducted either before or after a new medication is approved.

Pharmacological and psychosocial treatments for adolescents with ADHD: an updated systematic review of the literature

Smith, Waschbusch, Willoughby, and Evans (2000) reviewed a small treatment literature on ADHD in adolescents and concluded that methylphenidate stimulant medication was a well-established treatment and behavior therapy (BT) demonstrated preliminary efficacy. This review extends and updates the findings of the prior one based on the previous 15years of research. Studies published since 1999 were identified and coded using standard criteria and effect sizes were calculated where appropriate. Highlights of the last 15years of research include an expansion of pharmacological treatment options and developmentally appropriate psychosocial treatment packages for adolescents with ADHD. Additionally, nonstimulant medications (e.g., atomoxetine) are now approved for the treatment of ADHD in adolescence. The review concludes that medication and BT produce a similar range of therapeutic effects on the symptoms of adolescents with ADHD. However, results suggest that BT may produce greater overall benefits on measures of impairment. There was no evidence that cognitive enhancement trainings, such as working memory training or neurofeedback improved the functioning of adolescents with ADHD. Whether to use medication, BT, or their combination to treat an adolescent with ADHD is complicated and we provide evidence-informed guidelines for treatment selection. The reviewed evidence does not support current American Academy of Pediatrics and American Academy of Child and Adolescent Psychiatry professional guidelines, which state that stimulant medication is the preferred treatment for adolescents with ADHD. Recommendations for assessment, practice guidelines, and future research are discussed.

Attention-deficit/hyperactivity disorder with inadequate response to stimulants: approaches to management

Attention-deficit/hyperactivity disorder, or ADHD, is the most frequently occurring neurobiological disorder in childhood and is defined by symptoms of inattention and/or hyperactivity and impulsivity that are excessive when compared with other individuals at the same developmental level. ADHD can be successfully treated pharmacologically and stimulant medications are considered a first-line treatment. However, 20-35 % of subjects in clinical trials may have an inadequate response to initial stimulant treatment. There is no standard definition of inadequate response. In many clinical trials, response is defined as a percentage improvement on the Attention-Deficit/Hyperactivity Disorder Rating Scale alone, while in others the change in Clinical Global Impression-Improvement score has also been employed. Other outcome measures have also been used. A more meaningful definition for inadequate response is one that does not produce sufficient reduction of symptoms to produce functional improvement. The literature reveals many factors that may contribute to inadequate response to treatment. Among these are poor adherence, severity and/or complexity of ADHD, inadequate stimulant dosing and/or dose-limiting adverse effects. The reasons for poor adherence should be determined. Common factors include adverse effects, lack of effectiveness, concerns about addictive potential, difficulty ingesting the medication and cost. For patients with inadequate dosing, medication optimization should be tried. For those with dose-limiting adverse effects, switching to another stimulant class or a non-stimulant is an option. For patients who are partial responders to stimulants, despite adequate adherence and dose optimization, the addition of atomoxetine or guanfacine extended release or clonidine extended release may help them achieve adequate response.

Transdermal therapy for attention-deficit hyperactivity disorder with the methylphenidate patch (MTS)

Transdermal technology is currently approved in the US for the administration of more than 20 medications. This current review describes the clinical research pertaining to the use of a methylphenidate patch in the treatment of attention-deficit hyperactivity disorder (ADHD) in children and adolescents. PubMed searches were conducted using the search term 'methylphenidate transdermal system', and were limited to clinical trials. No limits were set for dates of publication. A total of 21 citations were identified. Studies evaluating the safety and efficacy of the methylphenidate transdermal system (MTS) in children and adolescents were included in this review. Additional studies were identified from bibliographies and the 'Related Citations' section of PubMed searches. The MTS delivers a range of methylphenidate doses using a drug-in-adhesive matrix patch. According to current labeling, the patch should be applied to the hip once daily for a maximum of 9 h. Serum methylphenidate levels increase over wear time, with mean time to maximum concentration (t max) reached between 8 and 10 h for a 9-h wear time, and the elimination half-life for methylphenidate is 3-4 h after patch removal. In clinical trials, ADHD symptoms were measured using the ADHD Rating Scale, Version IV, and several parent-, teacher-, and patient-rated scales. Treatment effects show statistically significant differences from baseline symptom scores starting at the first evaluation, 2 h after the patch is applied, with significant benefit lasting up to 12 h with a 9-h wear time. Adverse events with the MTS are similar to those seen with other formulations of methylphenidate, with the exception of skin-related reactions at the site of application, which were generally mild to moderate in severity. The incidence of contact allergic dermatitis with MTS is <1%. Statistically significant improvements in health-related quality of life and medication satisfaction were also observed with the MTS compared with placebo, and after switching from oral extended-release (ER) methylphenidate. Transdermal drug delivery is an effective and safe means of administering methylphenidate for patients with ADHD.

A Review of the Pathophysiology, Etiology, and Treatment of Attention-Deficit Hyperactivity Disorder (ADHD)

Objective: To review the pathophysiology, etiology, and treatment of attention-deficit hyperactivity disorder (ADHD). Data Sources and Data Extraction: A literature search was conducted in PubMed and EMBASE using the terms attention deficit hyperactive disorder, ADHD, pathophysiology, etiology, and neurobiology. Limits applied were the following: published in the past 10 years (January 2003 to August 2013), humans, review, meta-analysis, and English language. These yielded 63 articles in PubMed and 74 in EMBASE. After removing duplicate/irrelevant articles, 86 articles and their relevant reference citations were reviewed. Data Synthesis: ADHD is a neurological disorder that affects children, but symptoms may persist into adulthood. Individuals suffering from this disorder exhibit hyperactivity, inattention, impulsivity, and problems in social interaction and academic performance. Medications used to treat ADHD such as methylphenidate, amphetamine, and atomoxetine indicate a dopamine/norepinephrine deficit as the neurochemical basis of ADHD, but the etiology is more complex. Moreover, these agents have poor adverse effect profiles and a multitude of drug interactions. Because these drugs are also dispensed to adults who may have concomitant conditions or medications, a pharmacist needs to be aware of these adverse events and drug interactions. This review, therefore, focuses on the pathophysiology, etiology, and treatment of ADHD and details the adverse effects and drug interaction profiles of the drugs used to treat it. Conclusions: Published research shows the benefit of drug therapy for ADHD in children, but given the poor adverse effect and drug interaction profiles, these must be dispensed with caution.

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.

Long-acting methylphenidate reduces collision rates of young adult drivers with attention-deficit/hyperactivity disorder

This study investigated whether methylphenidate delivered through a long-acting transdermal system (MTS) would reduce collision rates of young adult drivers with attention-deficit/hyperactivity disorder (ADHD).Seventeen young adults completing the study (mean [SD] age, 20.82 [2.40] years; 14 men and 13 white) met the following inclusion criteria: ADHD diagnoses but not routinely taking ADHD medication, previously responsive to ADHD medication, active drivers with more than 1 collision or citation in the past 2 years, and no significant comorbidities. In this open-labeled, crossover design drivers were randomly assigned either to the no-medication condition for 3 months and then MTS for 3 months or to the reverse sequence. In-car video monitoring of routine driving occurred during these 6 months. At baseline and after each condition, participants completed the Conners Adult ADHD Rating Scale and the Cox Assessment of Risky Driving Scale, and their blood pressure, heart rate, and body weight were monitored.Compared with the no-medication condition, participants in the MTS condition self-reported fewer total ADHD (P < 0.04) and inattentive symptoms (P = 0.014) and a trend for risky driving behaviors (P = 0.059) and had fewer video-recorded collisions (P < 0.005) and other problematic driving events. There were no significant changes in blood pressure, heart rate, or body weight across conditions or any significant skin reactions to the MTS patch.This is the first study demonstrating that long-acting methylphenidate improves activities of daily living among young adults with ADHD. Specifically, methylphenidate improved safety in routine driving while reducing ADHD symptoms with minimal adverse effects.

Methylphenidate transdermal system: in attention-deficit hyperactivity disorder in adolescents

Methylphenidate transdermal system uses DOT Matrix™ technology and, once applied to the skin, releases methylphenidate continuously. In the US, methylphenidate transdermal system is indicated for use in the treatment of attention-deficit hyperactivity disorder (ADHD). According to the results of a randomized, double-blind, multicentre, 7-week trial (core trial), methylphenidate transdermal system 10-30 mg was effective in adolescents aged 13-17 years with ADHD. The mean ADHD-Rating Scale-IV (ADHD-RS-IV) total score (primary endpoint) decreased to a significantly greater extent in adolescents receiving methylphenidate transdermal system than in those receiving placebo transdermal system. Following the core trial, adolescents could subsequently receive methylphenidate transdermal system in an extension study of ≈6 months duration. From the start of the core trial to the end of the extension study, methylphenidate transdermal system recipients demonstrated a significant reduction in the mean ADHD-RS-IV total score. Methylphenidate transdermal system was generally well tolerated in adolescents with ADHD. The vast majority of treatment-emergent adverse events were of mild to moderate severity in both the short-term core trial and the longer-term extension study.

A 6-month, open-label, extension study of the tolerability and effectiveness of the methylphenidate transdermal system in adolescents diagnosed with attention-deficit/hyperactivity disorder

OBJECTIVE

The aim of this study was to evaluate the tolerability and effectiveness of the methylphenidate transdermal system (MTS) over 6 months in adolescents with attention-deficit/hyperactivity disorder (ADHD).

METHODS

This was an industry-sponsored, 30-center, open-label study of subjects aged 13-17 years with ADHD. Subjects were dose-optimized with MTS (10-30 mg/9 hours) over 5 weeks and then dose-maintained for up to 5 months. Tolerability evaluations included treatment-emergent adverse events (TEAEs) and dermal responses. Effectiveness was assessed with the ADHD-Rating Scale-IV (ADHD-RS-IV).

RESULTS

A total of 162 subjects received MTS treatment. The majority of TEAEs (>99%) were mild or moderate in intensity, and the most frequently reported TEAE was decreased appetite (15.4%). Thirteen subjects discontinued the study due to TEAEs. The majority (93.6%) of dermatologic reactions indicated mild erythema. There was significant improvement in mean ADHD-RS-IV total scores from study entry to end point (p<0.001).

CONCLUSION

Slightly more than half (54.0%) of subjects completed this 6-month, open-label extension study of MTS; the primary reason for discontinuation was withdrawn consent (36.0%). Reported TEAEs and skin tolerability findings were similar to those observed with MTS use in children and adolescents. MTS treatment resulted in a decrease in ADHD symptoms as rated by clinicians.