Effects of stimulant medication on growth rates across 3 years in the MTA follow-up

A pathophysiologic approach to growth problems in children with attention-deficit/hyperactivity disorder

In recent years there has been an increasing trend in the diagnosis and treatment of children with attention-deficit/hyperactivity disorder (ADHD) worldwide. One of the most frequently discussed side effects of these treatments is related to problems of growth. In order to better understand what ADHD is and the mechanisms by which it could affect growth, this article reviews relevant data from a clinical and neurophysiologic perspective to improve understanding of this controversial issue.

Outcome domains in child mental health research since 1996: have they changed and why does it matter?

OBJECTIVE

Child mental health treatment and services research yields more immediate public health benefit when they focus on outcomes of relevance to a broader group of stakeholders. We reviewed all experimental studies of child and adolescent treatment and service effectiveness published in the last 15 years (1996-2011) and compared the distribution and types of outcome domains to a prior review that focused on studies from the prior 15 years (1980-1995).

METHOD

Studies were included if they focused on children from birth to 18 years of age with specific or general psychiatric conditions, employed randomized designs, and examined intervention effects with a six-month or longer post-treatment assessment in treatment studies or a 6-month or longer post-baseline assessment for services studies. Two hundred (n=200) studies met criteria. Reported outcome measures were coded into conceptual categories drawn from the 1980-1995 review.

RESULTS

There was a five-fold increase in the total number of studies (38 versus 200) across the two 15-year time periods, with the largest increase in the number of studies that focused on consumer-oriented outcomes (from eight to 47 studies, an almost sixfold increase); two new domains, parent symptoms and health-related outcomes, were identified. The majority of studies (more than 95%) continued to focus on symptoms and diagnoses as an outcome. Impact ratings were higher among studies examining four or more outcomes versus one to two outcomes in all categories with the exception of Posttraumatic Stress Disorder.

CONCLUSIONS

Given major shifts in health care policy affecting mental health services, the emergence of health and parent-related outcomes as well as greater attention to consumer perspectives parallels emerging priorities in health care and can enhance the relevance of child outcome studies for implementation in the real world.

Chronic treatment with extended release methylphenidate does not alter dopamine systems or increase vulnerability for cocaine self-administration: a study in nonhuman primates

Despite the widespread use of stimulant medications for the treatment of attention deficit hyperactivity disorder, few studies have addressed their long-term effects on the developing brain or susceptibility to drug use in adolescence. Here, we determined the effects of chronic methylphenidate (MPH) treatment on brain dopamine (DA) systems, developmental milestones, and later vulnerability to substance abuse in juvenile nonhuman primates. Male rhesus monkeys (approximately 30 months old) were treated daily with either a sustained release formulation of MPH or placebo (N=8 per group). Doses were titrated to achieve initial drug blood serum levels within the therapeutic range in children and adjusted throughout the study to maintain target levels. Growth, including measures of crown-rump length and weight, was assessed before and after 1 year of treatment and after 3-5 months washout. In addition, positron emission tomography scans were performed to quantify binding availability of D2/D3 receptors and dopamine transporters (DATs). Distribution volume ratios were calculated to quantify binding of [¹⁸F]fluoroclebopride (DA D2/D3) and [¹⁸F]-(+)-N-(4-fluorobenzyl)-2β-propanoyl-3β-(4-chlorophenyl)tropane (DAT). Chronic MPH did not differentially alter the course of weight gain or other measures of growth, nor did it influence DAT or D2/D3 receptor availability after 1 year of treatment. However, after washout, the D2/D3 receptor availability of MPH-treated animals did not continue to decline at the same rate as control animals. Acquisition of intravenous cocaine self-administration was examined by first substituting saline for food reinforcement and then cocaine doses (0.001-0.1 mg/kg per injection) in ascending order. Each dose was available for at least five consecutive sessions. The lowest dose of cocaine that maintained response rates significantly higher than saline-contingent rates was operationally defined as acquisition of cocaine reinforcement. There were no differences in rates of acquisition, overall response rates, or cocaine intake as a function of cocaine dose between groups. In an animal model that closely mimics human development; chronic treatment with therapeutic doses of sustained release MPH did not have a significant influence on the regulation of DATs or D2/D3 receptors, or on standard measures of growth. Furthermore, this treatment regimen and subsequent drug washout did not have an impact on vulnerability to cocaine abuse.

Physical exercise and catecholamine reuptake inhibitors affect orienting behavior and social interaction in a rat model of attention-deficit/hyperactivity disorder

The effects of methylphenidate (MPH), atomoxetine (ATMX), and/or physical exercise (EX) on orienting behavior and social interaction were examined in spontaneously hypertensive rats (SHRs), a commonly used animal model of attention-deficit/hyperactivity disorder (ADHD). During the orienting procedure, rats received repeated presentations of a nonreinforced visual stimulus. As observed previously, orienting behavior (rearing up on the hind legs) habituated across trials in normo-active control rats (Wistars) but not in SHRs, suggesting that SHRs have difficulty ignoring irrelevant behavioral stimuli. Treatment with MPH (0.125 mg/kg), ATMX (0.125 mg/kg), or EX (3 weeks of access to a running wheel), alone or in combination, reduced rearing behavior in SHRs to the level observed in the Wistar control group. Similarly, drug treatment and/or EX reduced the number of social interactions exhibited by SHRs, while having no effects on locomotor activity. It is important to note that EX was just as effective as MPH or ATMX in reducing orienting behavior and social interaction. In contrast to the SHRs, neither MPH nor ATMX affected orienting or social behavior in Wistar rats. Together, these findings support the growing literature that EX may be useful as an adjunctive or replacement therapy in ADHD.

Management of psychotropic medication side effects in children and adolescents

This article is a review of several of the most concerning side effects of psychotropic medications in children and adolescents. An emphasis is placed on review of the prevalence, presentation, monitoring, and evidence-based management of these side effects.

Assessment of growth in pharmacological treatment-naïve Polish boys with attention-deficit/hyperactivity disorder

OBJECTIVE

The objective of this study was to estimate the growth of pharmacological treatment-naïve polish boys with attention-deficit/hyperactivity disorder (ADHD).

METHOD

The sample included 135 boys (mean age: 11.67 years) with ADHD. The level of subjects' height, weight, and body mass index (BMI) was compared to the reference growth charts. Full estimation of measurement accuracy was provided. Regression analysis was used to estimate the biological and social factors contributing to the growth determination in the examined group.

RESULTS

There were no statistically significant differences between mean body height of boys with ADHD and standards of growth of Polish children. Separate analyses for body height of the examined boys aged 6-10, 11-15, and 16-18 years also gave no statistically significant results. Mean body weight (z=0.28) and BMI (z=0.25) in the total cohort were statistically higher than the norm. After categorization of the boys according to age, statistically significant differences were demonstrated only for weight in the age range of 6-10 years (z=0.31) and for BMI in the age range of 11-15y (z=0.42). The regression analysis showed the strongest relation between the subjects' growth and the parents' body size, newborn's condition (birth, body weight, and APGAR score), factors connected with lifestyle, and socio-economic status of the family.

CONCLUSION

The study revealed that the height of drug-naïve boys with ADHD was not significantly different from the norm. The investigation also showed a tendency for greater body weight and BMI in boys with ADHD in comparison with the growth charts, which may be manifested also in greater risk of overweight and obesity in this group. The results of research suggest the necessity to control for such variables as genetic, perinatal, socioeconomic, and psychosocial factors, which may affect children's development, in future research on the growth of children with ADHD.

Chronic exposure to methylphenidate impairs appendicular bone quality in young rats

Methylphenidate (MP) is a psychostimulant widely prescribed to treat Attention Deficit Hyperactivity Disorder (ADHD). Although generally well tolerated, growth deficits have been reported in children and adolescents undergoing MP treatment. This study was designed to elucidate the skeletal effects of chronic MP administration in adolescent rats. Male, 4-week-old rats received one of two doses of MP (MP-Low or MP-High) delivered for 8 h a day via drinking water, or were untreated (water only). After 13 weeks, half were sacrificed (N=12/group) and the remaining rats were left to recover, untreated for 5 additional weeks. Femora, tibiae, and L5 vertebra were analyzed using calipers, DXA, and mechanical testing. Immediately following treatment, MP decreased femoral anterior-posterior diameter (5% and 9% for MP-Low and MP-High, respectively), femoral and tibial bone mineral density (BMD) (6% and 5% for MP-High femora and tibiae, respectively), and bone mineral content (BMC) (9% for MP-High femora and tibiae). In addition, femora from MP treated rats had reduced ultimate force (20% for MP-High) and energy to failure (20% and 33% for MP-Low and MP-High, respectively). However, after recovery, there were no statistically significant differences for any measured parameters. Despite these effects on the appendicular skeleton, no differences were identified between vertebral samples at either time-point. In summary, MP treatment resulted in smaller, less mineralized, and weaker bones at appendicular sites, but did not affect the axial site. Although these effects were ameliorated within 5 weeks, these data suggest that adolescents undergoing MP treatment may be at an increased risk for long bone fractures.

Correlates of weight gain during long-term risperidone treatment in children and adolescents

BACKGROUND

Most clinical trials of antipsychotics in children are brief, failing to address their long-term safety, particularly when taken concurrently with other psychotropics. This hypothesis-generating analysis evaluates potential correlates of weight gain in children receiving extended risperidone treatment.

METHODS

Medically healthy 7-17 year-old patients treated with risperidone for six months or more were enrolled. Anthropometric measurements were conducted. Developmental and medication history was obtained from the medical record. Information related to birth weight, dietary intake, physical activity, and parental weight was collected. Mixed regression analyses explored the contribution of various demographic and clinical factors to age- and sex-adjusted weight and body mass index (BMI) z scores over the treatment period.

RESULTS

The sample consisted of 110 patients (89% males) with a mean age of 11.8 years (sd = 2.9) upon enrollment. The majority had an externalizing disorder and received 0.03 mg/kg/day (sd = 0.02) of risperidone, for 2.5 years (sd = 1.7), to primarily target irritability and aggression (81%). Polypharmacy was common with 71% receiving psychostimulants, 50% selective serotonin reuptake inhibitors (SSRIs), and 32% α2-agonists. Weight and BMI z score were positively correlated with baseline weight at the start of risperidone, treatment duration, and the weight-adjusted dose of risperidone but inversely associated with the weight-adjusted dose of psychostimulants and the concurrent use of SSRIs and α2-agonists. The effect of risperidone dose appeared to attenuate as treatment extended while that of psychostimulants became more significant. The rate of change in weight (or BMI) z score prior to and within the first 12 weeks of risperidone treatment did not independently predict future changes neither did birth weight, postnatal growth, dietary intake, physical activity, or parental weight.

CONCLUSIONS

This comprehensive analysis exploring correlates of long-term weight (or BMI) change in risperidone-treated youths revealed that pharmacotherapy exerts significant but complex effects.

TRIAL REGISTRATION

Not applicable.

Effects of osmotic-release methylphenidate on height and weight in children with attention-deficit hyperactivity disorder (ADHD) following up to four years of treatment

There is some controversy concerning \the potential negative influence of methylphenidate on growth. The authors reviewed clinical records of 187 patients with attention-deficit hyperactivity disorder under treatment with methylphenidate. The patients' weight, height, and body mass index were measured at diagnosis and during 4 years of follow-up. The dose of methylphenidate was gradually increased up to 1.31 ± 0.2 mg/kg/d. At diagnosis, mean weight value was lower than mean weight expected for age by 0.697 kg. This difference increased to 4.274 kg (at 30 months of treatment), although it subsequently decreased to 1.588 kg (at 48 months of treatment). Mean value of height was lower than expected mean height for age by 0.42 cm at diagnosis. This difference increased to 2.69 cm (at 30 months of treatment), but it subsequently decreased to 0.83 cm (at 48 months of treatment). The relationship between nutritional status and the negative effects on the height curve in those patients would require nutritional optimization to return anthropometric variables to normal.

Iron status in toddlerhood predicts sensitivity to psychostimulants in children

OBJECTIVE

Iron deficiency is associated with impaired dopaminergic signaling and externalizing behavior. The authors examine, whether iron stores in toddlerhood influence later response to psychostimulants.

METHOD

Youth participating in a study monitoring the long-term safety of risperidone were included in this analysis if they had received psychostimulant monotherapy for at least 3 weeks and had a complete blood count obtained before psychostimulant treatment. Sensitivity to psychostimulants was defined based on the weight-adjusted dose during the 1st year of treatment. Regression analysis examined whether the hematological tests based on the characteristics of red blood cells were associated with sensitivity to psychostimulants.

RESULTS

A total of 29 participants (93% men; 76% Whites), primarily with ADHD (93%), comprised the current sample. The hematological tests were obtained, on average, 3 years before the initiation of psychostimulants monotherapy that occurred at 5.8 years of age and continued for a median of 0.85 years, at an average daily dose of 0.98 mg/kg (SD = 0.38) in methylphenidate equivalent. Compared with those who were poorly sensitive to psychostimulants, after adjusting for age, mean corpuscular volume was significantly higher in the highly and moderately psychostimulants sensitive groups.

CONCLUSIONS

If replicated, these findings suggest that more attention should be paid to optimizing body iron in early childhood.

Adverse events in medication treatment-naïve children with attention-deficit/hyperactivity disorder: results from a small, controlled trial of lisdexamfetamine dimesylate

OBJECTIVE

To evaluate the type, frequency, duration, and severity of treatment emergent adverse events (TEAEs) of the prodrug lisdexamfetamine dimesylate (LDX) in children with and without previous exposure to stimulant medication in the treatment of attention-deficit/hyperactivity disorder (ADHD).

METHODS

This single-blind, modified laboratory school study used open-label, dose optimization of children aged 6-12 years. LDX, initiated at 30 mg, was dose titrated in 20 mg increments to a possible 70 mg over 4-5 weeks. Safety was assessed using adverse effects and LDX levels.

RESULTS

Twenty-eight subjects enrolled in the study, with 27 safety protocol completers (n=14 previous stimulant exposure; n=13 stimulant naïve). The stimulant-naïve group reported more trouble sleeping, stomach pain, and hyperfocus, but only previous-exposure subjects experienced dizziness. Previous-exposure subjects showed trends of more decreased appetite, less talkativeness, and less lip sucking. There were no differences in the mean duration of TEAEs. The epidemiological method of percent person-weeks applied to ADHD treatment offers a novel approach to interpreting the pattern of TEAEs.

CONCLUSION

LDX reduced the core symptoms of ADHD with more severe adverse events in stimulant-naïve than previous-exposure subjects. Future controlled studies with larger samples should address the impact of previous stimulant exposure on other ADHD treatments.

Blood pressure and heart rate over 10 years in the multimodal treatment study of children with ADHD

OBJECTIVE

It is unknown whether prolonged childhood exposure to stimulant medication for the treatment of attention deficit hyperactivity disorder (ADHD) increases the risk for developing abnormalities in blood pressure or heart rate. The authors examined the association between stimulant medication and blood pressure and heart rate over 10 years.

METHOD

A total of 579 children, ages 7–9, were randomly assigned to 14 months of medication treatment, behavioral therapy, the combination of the two, or usual community treatment. The controlled trial was followed by naturalistic treatment with periodic assessments. Blood pressure and heart rate data were first analyzed with linear regression models based on an intent-to-treat approach, using raw data and the blood pressure categories of prehypertension and hypertension. Currently medicated patients were then compared with never or previously medicated patients. Associations between cumulative stimulant exposure and blood pressure or heart rate were assessed.

RESULTS

No treatment effect on either systolic or diastolic blood pressure could be detected. Children who were treated with stimulants had a higher heart rate (mean=84.2 bpm [SD=12.4] on medication alone and mean=84.6 bpm [SD=12.2] on medication plus behavioral therapy) than those who were treated with behavioral therapy alone (mean=79.1 bpm [SD=12.0]) or those who received usual community treatment (mean=78.9 bpm [SD=12.9]) at the end of the 14-month controlled trial, but not thereafter. Stimulant medication did not increase the risk for tachycardia, but greater cumulative stimulant exposure was associated with a higher heart rate at years 3 and 8.

CONCLUSIONS

Stimulant treatment did not increase the risk for prehypertension or hypertension over the 10-year period of observation. However, stimulants had a persistent adrenergic effect on heart rate during treatment.

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.

ADHD: clinical practice guideline for the diagnosis, evaluation, and treatment of attention-deficit/hyperactivity disorder in children and adolescents

Attention-deficit/hyperactivity disorder (ADHD) is the most common neurobehavioral disorder of childhood and can profoundly affect the academic achievement, well-being, and social interactions of children; the American Academy of Pediatrics first published clinical recommendations for the diagnosis and evaluation of ADHD in children in 2000; recommendations for treatment followed in 2001.

Update on attention deficit hyperactivity disorder

Attention deficit hyperactivity disorder (ADHD) is now the most frequent diagnosis in children seen by Australian general paediatricians. It is a heterogeneous neurodevelopmental disorder and is usually accompanied by one or more co-morbid developmental and/or mental health conditions. In addition to daily symptoms, which often impair quality of life, ADHD can compromise educational and social development for the individual, and impact on families, schools and the broader community. Draft revised National Health and Medical Research Council Guidelines on ADHD were published in November 2009. This comprehensive document discusses the evidence in relation to many aspects of ADHD, which inform the large number of practice recommendations. Although there is an enormous literature on the causes, neurobiology and management of ADHD, there is still much to be learned particularly in relation to early intervention, behavioural therapies and factors influencing long-term outcomes.

Pubertal delay in male nonhuman primates (Macaca mulatta) treated with methylphenidate

Juvenile male rhesus monkeys treated with methylphenidate hydrochloride (MPH) to evaluate genetic and behavioral toxicity were observed after 14 mo of treatment to have delayed pubertal progression with impaired testicular descent and reduced testicular volume. Further evaluation of animals dosed orally twice a day with (i) 0.5 mL/kg of vehicle (n = 10), (ii) 0.15 mg/kg of MPH increased to 2.5 mg/kg (low dose, n = 10), or (iii) 1.5 mg/kg of MPH increased to 12.5 mg/kg (high dose, n = 10) for a total of 40 mo revealed that testicular volume was significantly reduced (P < 0.05) at months 15 to 19 and month 27. Testicular descent was significantly delayed (P < 0.05) in the high-dose group. Significantly lower serum testosterone levels were detected in both the low- (P = 0.0017) and high-dose (P = 0.0011) animals through month 33 of treatment. Although serum inhibin B levels were increased overall in low-dose animals (P = 0.0328), differences between groups disappeared by the end of the study. Our findings indicate that MPH administration, beginning before puberty, and which produced clinically relevant blood levels of the drug, impaired pubertal testicular development until ∼5 y of age. It was not possible to resolve whether MPH delayed the initiation of the onset of puberty or reduced the early tempo of the developmental process. Regardless, deficits in testicular volume and hormone secretion disappeared over the 40-mo observation period, suggesting that the impact of MPH on puberty is not permanent.

To stop or not to stop? How long should medication treatment of attention-deficit hyperactivity disorder be extended?

ADHD is a common neuropsychiatric disorder with a strong persistence over time. Medication is frequently used in the clinical management of ADHD. After response, medication is typically prescribed for months to years. It is unclear whether extended medication treatment provides long-term benefits and how long it should be continued. Furthermore, there is concern about the long-term safety of ADHD medication. The aim of this systematic review is to address these issues and provide recommendations about the decision to stop or not to stop ADHD medication. We performed a search in PubMed and focused on medication studies with a treatment longer than 12weeks in subjects 6-18years old. Extended placebo-controlled double-blind parallel studies are not available. Placebo-controlled discontinuation studies and prospective long-term observational treatment studies provide evidence that medication management leads to a substantial reduction of ADHD symptoms and less impairment of functioning for a period of about 2years. There is limited and inconsistent evidence for long-term advantage of medication treatment beyond symptom control, such as improved social functioning, academic achievement, employment status and less adverse psychiatric outcome. In terms of safety, long-term effects of medication on growth, blood pressure and heart rate are limited and the occurrence of suicidal, psychotic and manic symptoms is rare. Animal data about neurotoxic effects of psycho stimulants cannot be directly extrapolated to humans. Therefore, clinical decisions about starting, continuing, and stopping of ADHD medication should be made on an individual basis. Medication free periods should be implemented at regular times to investigate the need for an ongoing benefit of medication. Unfounded assumptions about continuing benefit of medication use should be abandoned. Careful monitoring of side effects is necessary and must be able to detect early alarming signals.

Age-grouped differences in adverse drug events from psychotropic medication

OBJECTIVE

This review aims to detail specific psychotropic medication treatment differences in adverse drug events (ADEs) between children, adolescents, and adults.

METHOD

A thorough data-based search of ADEs was made, augmented by findings from approved and updated U.S. Food and Drug Administration (FDA) drug labels, controlled clinical trial reports, and from FDA information on ADEs at scheduled public hearings.

RESULTS

Children were found to generally exhibit more ADEs to psychotropic medication than adolescents and adults. These ADEs primarily include altered growth velocity, rash, vomiting, dystonia, tics, affect lability, activation, metabolic blood test abnormalities, sedation, sialorrhea, and electrocardiogram irregularities.

CONCLUSION

Children have more biological vulnerabilities than older individuals, which could account for their greater rate of ADEs to psychotropic medication treatment.

Long-term outcomes with medications for attention-deficit hyperactivity disorder: current status of knowledge

Attention-deficit hyperactivity disorder (ADHD), a common neurobehavioural disorder characterized by inattention, hyperactivity and impulsivity, is a chronic disorder and often persists into adulthood. CNS stimulants have been the most well known treatment for ADHD for several decades due to their high effectiveness, good safety profiles and relatively minor adverse effects. Non-stimulant agents, including atomoxetine, extended-release guanfacine and extended-release clonidine (US FDA approved), and several non-FDA-approved agents, such as bupropion and tricyclic antidepressants (TCAs), were recently proven to be effective alternatives to the stimulants in several open-label and placebo-controlled trials. However, most medication trials for ADHD have been short term and thus have not provided information on the long-term outcomes of ADHD treatment. Since the medical treatment of many children with ADHD, especially those with more severe symptoms or co-morbid disorders, has to be continued for several years, recent studies have shifted their focus from the acute effectiveness of stimulants or non-stimulant drugs to the long-term outcomes of medications for ADHD. Evidence has shown that stimulants, along with the non-stimulants atomoxetine and extended-release guanfacine, are continuously effective for 24-month treatment periods with few and tolerable adverse effects.

The adolescent outcome of children with attention deficit hyperactivity disorder treated with methylphenidate or methylphenidate combined with multimodal behaviour therapy: results of a naturalistic follow-up study

OBJECTIVE

Children with attention deficit hyperactivity disorder (ADHD) who participated in a randomized clinical trial, which compared a brief intensive multimodal behaviour therapy combined with optimally titrated methylphenidate to optimally titrated methylphenidate alone (n = 45), were re-assessed at adolescence in a naturalistic follow-up 4.5 to 7.5 years after treatment. Also a matched normal control group was recruited (n = 23).

METHODS

Assessments at follow-up included diagnostic status, ADHD symptoms, oppositional and conduct behaviour, substance abuse symptoms and parenting stress.

RESULTS

Of the 24 adolescents participating in the follow-up study, 50% still met diagnostic criteria for ADHD. There were no significant differences between adolescents at follow-up and those lost for follow-up. At follow-up, adolescents in the combined treatment condition used significantly less medication than children in the methylphenidate condition; there were no other significant differences between the treatment conditions. The adolescents showed a significant decline in hyperactivity/impulsivity, oppositional and conduct disorder symptoms from post-test to follow-up. Only inattention symptoms increased from post-test to follow-up but not to pre-test levels. The adolescents originally diagnosed with ADHD fared significantly worse than the matched controls on all outcomes, except on conduct disorder and substance abuse symptoms.

CONCLUSIONS

Our study shows in adolescents, diagnosed with ADHD in childhood, age-dependent decline of ADHD symptoms, although they still fared significantly worse than matched normal controls. Implications of results are restricted by small samples size, and the results may be subject to chance findings and need replication before firm conclusions can be drawn.

Framework conditions facilitating paediatric clinical research

The use of unlicensed and "off-label" medicines in children is widespread. Between 50-80% of the medicines currently administered to children have neither been tested nor authorized for their use in the paediatric population which represents approximately 25% of the whole European population. On 26 January 2007, entered into force the European Regulation of Paediatric Medicines. It aims at the quality of research into medicines for children but without subjecting the paediatric population to unnecessary clinical trial. This article addresses ethical and legal issues arising from the regulation and makes recommendations for the framework conditions facilitating the development of clinical research with children.

Effects of physical exercise on ADHD-like behavior in male and female adolescent spontaneously hypertensive rats

The present study examined the effects of exercising (voluntary wheel running) during adolescence on attentional function in male and female spontaneously hypertensive rats (SHRs), a commonly used animal model of attention-deficit/hyperactivity disorder (ADHD). Once rats reached adulthood, they received one session in which a light was presented 12 times but not reinforced, followed by training sessions in which the light was paired with a food reward. Male and female SHRs that had access to running wheels exhibited levels of unconditioned orienting behavior that were similar to Wistar-Kyoto rats (normo-active control) while SHRs that did not have access to running wheels exhibited higher levels of unconditioned orienting behavior. When the light was later paired with food there were no differences between the groups of male rats, but exercising female SHRs exhibited a decrease in conditioned food cup behavior. Consistent with their established phenotype, SHR rats exhibited more locomotor activity during an open field exploration session than WKY rats, but there was no relationship between orienting behavior and locomotor activity. Together these data suggest that physical exercise during adolescence can benefit attentional capabilities.

Pharmacotherapy for child and adolescent attention-deficit hyperactivity disorder

Research in the past 2 decades showed that attention-deficit/hyperactivity disorder (ADHD) is a frequently occurring psychiatric disorder that causes considerable suffering to patients and their families. This article outlines current pharmacologic ADHD treatment options and focuses on their safety profile and efficacy. In addition, it addresses treatment selection, guidelines for monitoring treatment, and recent controversies in the field.

Neuroethical issues in cognitive enhancement

Neuroethics is a developing field, concerned with addressing present and future applied ethical issues brought about directly and indirectly by neuroscience advancements. One domain where neuroscience has begun to have far-reaching ethical implications is in the research and development of pharmaceutical cognitive enhancers. Though such drugs are typically developed to treat cognitive disabilities and improve the quality of life for patients with neuropsychiatric disorders and brain injury, research has found that such drugs can improve performance on cognitive tasks in healthy individuals. In line with such findings is the growing use of these drugs by students and others for cognitive-enhancing purposes. The present paper reviews some of the evidence in both neuropsychiatric and healthy individuals and discusses the implications such research can have for society.

European guidelines on managing adverse effects of medication for ADHD

The safety of ADHD medications is not fully known. Concerns have arisen about both a lack of contemporary-standard information about medications first licensed several decades ago, and signals of possible harm arising from more recently developed medications. These relate to both relatively minor adverse effects and extremely serious issues such as sudden cardiac death and suicidality. A guidelines group of the European Network for Hyperkinetic Disorders (EUNETHYDIS) has therefore reviewed the literature, recruited renowned clinical subspecialists and consulted as a group to examine these concerns. Some of the effects examined appeared to be minimal in impact or difficult to distinguish from risk to untreated populations. However, several areas require further study to allow a more precise understanding of these risks.

Effect of atomoxetine on Tanner stage sexual development in children and adolescents with attention deficit/hyperactivity disorder: 18-month results from a double-blind, placebo-controlled trial

OBJECTIVE

To determine the effects of long-term atomoxetine treatment on sexual development in children and adolescents with attention-deficit/hyperactivity disorder (ADHD) as compared with placebo and with a national US survey in non-Hispanic white children and adolescents.

METHODS

This double-blind, placebo-controlled, relapse prevention, multicenter trial was conducted in pediatric patients (6-15 years) with DSM-IV diagnosed ADHD and lasting for ∼ 18 months. All patients received 10 weeks of open-label atomoxetine treatment (0.5-1.8 mg/kg/day). Patients responding in the last 2 weeks of treatment were randomized to double-blind treatment with either placebo or atomoxetine for up to 9 months, after which atomoxetine patients were re-randomized to either continued atomoxetine treatment or to placebo for up to another 6 months. Patients randomized to placebo at first randomization remained on placebo. The Tanner stage was assessed by the investigator at baseline and at approximately 6, 12, and 18 months, and the rate of sexual development (change in the Tanner stage) was compared between treatment groups.

RESULTS

No statistically significant differences were observed between treatment groups either in sexual development (mean time, in days, to the first Tanner stage change: atomoxetine, 464.3 ± 23.0; placebo, 433.1 ± 14.4; p = 0.33) or in the duration of treatment exposure (atomoxetine, 315.3 days; placebo, 315.1 days; p = 0.90). Similar proportions of patients had at least one Tanner stage increase (atomoxetine: 27.1%; placebo: 31.9%; p = 0.39). Proportions of patients in each baseline Tanner stage group moving to higher stages were not statistically significantly different (p = 0.88, p = 0.18, p > 0.99, p = 0.68 for baseline Tanner stages 1-4, respectively). The puberty onset age was similar across treatment groups and consistent with US normative data.

CONCLUSIONS

Long-term atomoxetine treatment was not associated with any appreciable impact on or delay in sexual maturation in children with ADHD compared with US normative data.

LIMITATIONS

Study limitations include the relatively short duration of exposure to atomoxetine treatment, and the fact that half of the patients had been previously treated with stimulants. In addition, the Tanner stage data were collected as a secondary measure.

A common variant of the latrophilin 3 gene, LPHN3, confers susceptibility to ADHD and predicts effectiveness of stimulant medication

Attention-Deficit/Hyperactivity Disorder (ADHD) has a very high heritability (0.8), suggesting that about 80% of phenotypic variance is due to genetic factors. We used the integration of statistical and functional approaches to discover a novel gene that contributes to ADHD. For our statistical approach, we started with a linkage study based on large multigenerational families in a population isolate, followed by fine mapping of targeted regions using a family-based design. Family- and population-based association studies in five samples from disparate regions of the world were used for replication. Brain imaging studies were performed to evaluate gene function. The linkage study discovered a genome region harbored in the Latrophilin 3 gene (LPHN3). In the world-wide samples (total n=6360, with 2627 ADHD cases and 2531 controls) statistical association of LPHN3 and ADHD was confirmed. Functional studies revealed that LPHN3 variants are expressed in key brain regions related to attention and activity, affect metabolism in neural circuits implicated in ADHD, and are associated with response to stimulant medication. Linkage and replicated association of ADHD with a novel non-candidate gene (LPHN3) provide new insights into the genetics, neurobiology, and treatment of ADHD.

A naturalistic 10-year prospective study of height and weight in children with attention-deficit hyperactivity disorder grown up: sex and treatment effects

OBJECTIVE

To assess the effect of attention-deficit/hyperactivity disorder (ADHD) and its treatment on growth outcomes in children followed into adulthood.

STUDY DESIGN

Two identically designed, longitudinal, case-control studies of males and females with and without ADHD were combined; 124 and 137 control and subjects with ADHD, respectively, provided growth information at the 10- to 11-year follow-up. We used linear growth curve models to estimate the effect of time on change in height and whether this effect differed by sex and ADHD status. We also examined the effect of stimulant treatment on growth outcomes.

RESULTS

We found no evidence that ADHD was associated with trajectories of height over time or differences at follow-up in any growth outcomes. Similarly, we found no evidence that stimulant treatment was associated with differences in growth. However, among subjects with ADHD, major depression was associated with significantly larger weight in females and smaller height in males.

CONCLUSIONS

Our results do not support an association between deficits in growth outcomes and either ADHD or psychostimulant treatment for ADHD. These findings extend the literature on this topic into young adulthood and should assist clinicians and parents in formulating treatment plans for children with ADHD.

European consensus statement on diagnosis and treatment of adult ADHD: The European Network Adult ADHD

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) is among the most common psychiatric disorders of childhood that persists into adulthood in the majority of cases. The evidence on persistence poses several difficulties for adult psychiatry considering the lack of expertise for diagnostic assessment, limited treatment options and patient facilities across Europe.

METHODS

The European Network Adult ADHD, founded in 2003, aims to increase awareness of this disorder and improve knowledge and patient care for adults with ADHD across Europe. This Consensus Statement is one of the actions taken by the European Network Adult ADHD in order to support the clinician with research evidence and clinical experience from 18 European countries in which ADHD in adults is recognised and treated.

RESULTS

Besides information on the genetics and neurobiology of ADHD, three major questions are addressed in this statement: (1) What is the clinical picture of ADHD in adults? (2) How can ADHD in adults be properly diagnosed? (3) How should ADHD in adults be effectively treated?

CONCLUSIONS

ADHD often presents as an impairing lifelong condition in adults, yet it is currently underdiagnosed and treated in many European countries, leading to ineffective treatment and higher costs of illness. Expertise in diagnostic assessment and treatment of ADHD in adults must increase in psychiatry. Instruments for screening and diagnosis of ADHD in adults are available and appropriate treatments exist, although more research is needed in this age group.

The influences of environmental enrichment, cognitive enhancement, and physical exercise on brain development: can we alter the developmental trajectory of ADHD?

Attention-deficit/Hyperactivity Disorder (ADHD) is characterized by a pervasive pattern of developmentally inappropriate inattentive, impulsive and hyperactive behaviors that typically begin during the preschool years and often persist into adulthood. The most effective and widely used treatments for ADHD are medication and behavior modification. These empirically-supported interventions are generally successful in reducing ADHD symptoms, but treatment effects are rarely maintained beyond the active intervention. Because ADHD is now generally thought of as a chronic disorder that is often present well into adolescence and early adulthood, the need for continued treatment throughout the lifetime is both costly and problematic for a number of logistical reasons. Therefore, it would be highly beneficial if treatments would have lasting effects that remain after the intervention is terminated. This review examines the burgeoning literature on the underlying neural determinants of ADHD along with research demonstrating powerful influences of environmental factors on brain development and functioning. Based upon these largely distinct scientific literatures, we propose an approach that employs directed play and physical exercise to promote brain growth which, in turn, could lead to the development of potentially more enduring treatments for the disorder.

Nutritional status of children with attention deficit hyperactivity disorder: a pilot study

Objectives. This is a pilot study of the dietary intake and nutrient status of children with Attention Deficit Hyperactivity Disorder (ADHD). Method. Nutritional assessment of 43 children aged 6–12 with ADHD was performed using a 3-day food record, 24-hour recall, and serum assessors. Results. Macronutrient intake and consumption of Low-Nutrient Foods were comparable to population norms; however, 66% were found to be deficient in zinc and 23% in copper. Conclusions. This pilot study reports the food intake and nutrient status of children with ADHD and shows a predisposition for low zinc and copper status in ADHD.

Developmental phenotypes and causal pathways in attention deficit/hyperactivity disorder: potential targets for early intervention?

Early intervention approaches have rarely been implemented for the prevention of attention deficit/hyperactivity disorder (ADHD). In this paper we explore whether such an approach may represent an important new direction for therapeutic innovation. We propose that such an approach is most likely to be of value when grounded in and informed by developmental models of the dynamic, complex and heterogeneous nature of the condition. First, we set out a rationale for early intervention grounded in the science of ADHD viewed through developmental models. Second, we re-examine the concept of disorder-onset from the perspective of developmental trajectories and phenotypes. Third, we examine potential causal pathways to ADHD with regard to originating risk, pathophysiological mediators, environmental moderators and developmental continuities. Finally, we explore the potential value of strategies for identifying young children at risk for ADHD, and implementing interventions in ways that can target these underlying pathogenic processes. The utility of such an approach represents an important area for future research but still requires 'proof of concept'. Therefore prior to widespread clinical implementation, far greater knowledge is required of (i) developmental pathways into ADHD, (ii) the value of identifying neuropsychological mediators of these pathways, and (iii) the extent to which targeting mediating mechanisms will improve treatment outcomes for children with ADHD.

Treating attention-deficit/hyperactivity disorder beyond symptom control alone in children and adolescents: a review of the potential benefits of long-acting stimulants

Attention-deficit/hyperactivity disorder (ADHD), one of the most common neuropsychiatric conditions of childhood, often has a chronic course and persists into adulthood in many individuals. ADHD may have a clinically important impact on health-related quality of life in children, a significant impact on parents' emotional health and interfere with family activities/cohesion. To date, the main targets of ADHD treatment have focused on reducing the severity of symptoms during the school day and improving academic performance. However, the treatment of ADHD should reach beyond symptom control to address the issues of social competencies and improvement of health-related quality of life from the perspectives of individuals with ADHD and their families, to support them in reaching their full developmental potential. Methylphenidate (MPH) is recognised as the first-line choice of pharmacotherapy for ADHD in children and adolescents. This paper focuses on the importance and benefits to child development of ADHD symptom control beyond the school day only, i.e. extending into late afternoon and evening and uses the example of an extended-release MPH formulation (OROS((R)) MPH) to demonstrate the potential benefits of active full day coverage (12 h) with a single daily dose. Concerns of long-term stimulant treatment are also discussed.

Bulimia nervosa symptoms in the multimodal treatment study of children with ADHD

OBJECTIVE

We investigated body image dissatisfaction and bingeing/purging characteristics of bulimia nervosa (BN) in the ongoing prospective follow-up of the Multimodal Treatment Study of Children with attention-deficit/hyperactivity disorder (ADHD).

METHOD

Participants were 337 boys and 95 girls with ADHD and 211 boys and 53 girls forming a local normative comparison group (LNCG), reassessed in midadolescence (mean age, 16.4), 8 years after original recruitment.

RESULTS

Youth with childhood ADHD showed more BN symptoms in midadolescence than did LNCG youth, and girls demonstrated more BN symptoms than did boys, with effect sizes between small and medium. Childhood impulsivity, as opposed to hyperactivity or inattention, best predicted adolescent BN symptoms, particularly for girls. Among youth with ADHD, treatment received during the follow-up period was not associated with BN pathology.

DISCUSSION

Both boys and girls with ADHD may be at risk for BN symptoms in adolescence because of the impulsivity central to both disorders.

A pilot study of combined working memory and inhibition training for children with AD/HD

Building on recent favourable outcomes using working memory (WM) training, this study examined the behavioural and physiological effect of concurrent computer-based WM and inhibition training for children with attention-deficit hyperactivity disorder (AD/HD). Using a double-blind active-control design, 29 children with AD/HD completed a 5-week at-home training programme and pre- and post-training sessions which included the assessment of overt behaviour, resting EEG, as well as task performance, skin conductance level and event-related potentials (ERPs) during a Go/Nogo task. Results indicated that after training, children from the high-intensity training condition showed reduced frequency of inattention and hyperactivity symptoms. Although there were trends for improved Go/Nogo performance, increased arousal and specific training effects for the inhibition-related N2 ERP component, they failed to reach standard levels of statistical significance. Both the low- and high-intensity conditions showed resting EEG changes (increased delta, reduced alpha and theta activity) and improved early attention alerting to Go and Nogo stimuli, as indicated by the N1 ERP component, post-training. Despite limitations, this preliminary work indicates the potential for cognitive training that concurrently targets the interrelated processes of WM and inhibition to be used as a treatment for AD/HD.

Global and local morphometric differences in recently abstinent methamphetamine-dependent individuals

Methamphetamine (MA) is associated with behavioral and cognitive deficits that may be related to macrostructural abnormalities. Quantitative anatomical comparisons between controls and methamphetamine-dependent individuals have produced conflicting results. We examined local and global differences in brain structure in 61 abstinent methamphetamine-dependent individuals and 44 controls with voxel-based morphometry and tissue segmentation. We related regional differences in gray matter density and whole brain segmentation volumes to performance on a behavioral measure of impulsivity and group membership using multiple linear regression. Within the MA group, we related cortical and subcortical gray matter density to length of abstinence. Controls had greater density relative to MA in bilateral insula and left middle frontal gyrus. Impulsivity was higher in the MA group and, within all subjects, impulsivity was positively correlated with gray matter density in posterior cingulate cortex and ventral striatum and negatively correlated in left superior frontal gyrus. Length of abstinence from MA was associated with greater amygdalar density. Earlier age of first use of MA (in subjects who initiated use before age 21) was associated with smaller intracranial volume. The findings are consistent with multiple possible mechanisms including neuroadaptations due to addictive behavior, neuroinflammation as well as dopaminergic and serotonergic neurotoxicity.

Leptin gene -2548G/A variants predict risperidone-associated weight gain in children and adolescents

OBJECTIVE

As the use of atypical antipsychotics in children and adolescents has increased, concerns have been raised about their long-term safety. We aimed to investigate the association between risperidone-induced weight gain, leptin concentration, and the leptin gene (LEP) -2548G/A variants in youths.

METHODS

Medically healthy 7- to 17-year-old children and adolescents, in extended naturalistic treatment with risperidone, were recruited through pediatric psychiatry clinics. Anthropometric measures and laboratory testing were conducted. Growth and medication history was obtained from the medical record. The effect of the LEP genotypes on leptin concentration and on the slopes of the weight and body mass index (BMI) Z-score curves before and after the onset of risperidone treatment was investigated .

RESULTS

In 74 individuals, chronically treated with risperidone, the A allele was associated with higher leptin concentration at low weight and BMI Z-scores. There was no effect of the LEP genotypes on weight or BMI Z-scores before risperidone was started. Afterwards, however, the A-allele carriers showed a steeper rate of increase in weight and BMI Z-scores. As a result, the GG-genotype carriers were 2.5 times less likely to be overweight/obese (i.e. having a BMI above the 85th percentile). This genetic effect on risperidone-associated weight gain did not extend to weight loss related to psychostimulants.

CONCLUSION

The LEP - 2548G/A variants seem to moderate the weight-altering effect of risperidone but not psychostimulants. This may be related to genetic differences in tissue sensitivity to leptin, resulting in differential body composition.

Effects of lisdexamfetamine dimesylate treatment for ADHD on growth

OBJECTIVE

To complete an exploratory uncontrolled study of the effects of lisdexamfetamine dimesylate (LDX) on growth of children treated for attention-deficit/hyperactivity disorder (ADHD).

METHOD

Height, weight, and body mass index (BMI) from 281 children ages 6 to 13 years from longitudinal assessments up to 15 months were compared to norms from the Centers for Disease Control.

RESULTS

At study entry, children were taller and heavier than average. Growth delays were largest for weight and BMI, and there was a 13 percentile point decrease in height. Children continued to grow in terms of height while treated with LDX; we found no increase in raw weight or BMI during the study period. LDX treatment was significantly associated with diminished gains in height, weight, and BMI compared to levels that would be expected based on age-appropriate standards from the Centers for Disease Control. Growth delays were greatest for the heaviest and tallest children, for those who had not previously received stimulant therapy, and for those with a greater cumulative exposure to LDX. More work is needed to determine effects on ultimate adult height.

CONCLUSIONS

Consistent with prior studies of stimulants, treatment with LDX leads to statistically significant reductions in expected height, weight, and BMI. Growth of patients with ADHD treated with LDX should be closely monitored and corrective action taken should growth delays be observed.

Adverse reactions to methylphenidate treatment for attention-deficit/hyperactivity disorder: structure and associations with clinical characteristics and symptom control

BACKGROUND

Methylphenidate (MPH)-related adverse events are well characterized. Their predictors and their relationship with therapeutic effects are less well understood. Here we examine these issues in relation to two long-acting formulations.

METHOD

Comparison of Methylphenidates in the Analog Classroom Setting (COMACS) was made in a large (n = 184) placebo-controlled trial comparing Equasym XL/Metadate CD, Concerta, and placebo (PLA) using a Laboratory School protocol. Therapeutic effects were measured using direct observation, scores on a simple math productivity task and parent ratings. Parents also completed the Barkley Stimulant Side Effect Rating Scale (BSSERS).

RESULTS

The BSSERS had six factors: Emotionality, sleep/appetite, disengaged, dizzy, uninterested, and aches. Treatment effects were seen only for emotionality (which improved) and sleep and appetite (which worsened). Adverse events were not predictable from personal and clinical characteristics of patients. Sleep/appetite adverse events were not associated with therapeutic effects. Improvements in attention-deficit/hyperactivity disorder (ADHD) and emotionality were correlated.

DISCUSSION

The results support a narrow conceptualization of MPH adverse events with problems restricted to appetite and sleep. These effects were not predictable on the basis of available information and may be due to an underlying mechanism rather distinct from those determining therapeutic effects.

Efficacy and safety limitations of attention-deficit hyperactivity disorder pharmacotherapy in children and adults

There have been major advances in the treatment and understanding of attention-deficit hyperactivity disorder (ADHD) in the last decade. Among these are the availability of newer stimulant formulations, an appreciation of the combined effects of medication and behavioural therapies, and a better understanding of the neurobiology of the disorder in children (aged 6-12 years), adolescents and adults. This article focuses on the evaluation of the efficacy and safety profiles of medications used for the management of ADHD. In assessing the various medical treatments for ADHD, certain issues and analyses have become important to address. The diagnosis, characterization and quantification of ADHD symptoms are crucial to assessing treatment effectiveness. A standardized setting for measuring the severity of ADHD symptoms is the laboratory school protocol, which simulates a school environment with tightly controlled timing of measurements. This method has been adapted successfully to the adult workplace environment to help with the evaluation of adult ADHD symptoms. Statistical analyses, such as effect size and number needed to treat, may aid in the comparison and interpretation of ADHD study results. Although an objective approach to evaluating the efficacy and safety profiles of the available medications provides necessary details about the medical options, typical clinical decisions are often based on trial and error and may be individualized based on a patient's daily routine, comorbidities and risk factors. Stimulants remain the US FDA-approved medical treatment of choice for patients with ADHD and are associated with an exceptional response rate. Findings of the Multimodal Treatment of Children With ADHD study suggest that the combination of behavioural and medical therapy may benefit most patients. Nonstimulant agents, such as atomoxetine (FDA-approved), and several non-approved agents, bupropion, guanfacine and clonidine, may offer necessary alternatives to the stimulants. This is especially important for patients who have comorbidities that are contraindicated for stimulant use based on medical issues and/or risk for stimulant abuse. Typical psychiatric comorbidities in patients with ADHD include oppositional defiant disorder, conduct disorder, major depressive disorder, bipolar disorder, anxiety, substance abuse disorder, tic disorder, and Tourette's syndrome. Although relatively safe, both stimulants and atomoxetine have class-related warnings and contraindications and are associated with adverse effects that require consideration when prescribing. Polypharmacy is a common psychiatric approach to address multiple symptoms or emergent adverse effects of necessary treatments. Future research may provide an improved understanding of polypharmacy and better characterization of the factors that influence the diagnosis and successful treatment of patients with ADHD.