Practice parameter for the use of stimulant medications in the treatment of children, adolescents, and adults

Clinical evaluation of subjective and objective changes in motor activity and attention in children with attention-deficit/hyperactivity disorder in a double-blind methylphenidate trial

The aim of this study was to determine drug-dependent effects on attention and motor activity in children with attention-deficit/hyperactivity disorder (ADHD) in a double-blind methylphenidate (MPH) trial using both subjective behavior ratings and objective measures of function. In particular, we were interested in the relationship between changes of those subjective and objective measures. A total of 44 ADHD children with the combined subtype completed a randomized, double-blind, placebo-controlled, crossover trial with 2 doses of MPH (0.25; 0.5 mg/kg body weight) and placebo. In each condition, computerized attention tasks were performed, teacher-behavior ratings were obtained, and actigraph data were collected in both clinical and naturalistic settings. Trend tests revealed linear effects of MPH dose on actigraph data in the test session (p = 0.02) and at school (p = 0.001), as well as on sustained attention (p < 0.001), while inhibitory control showed a quadratic dose-response curve (p < 0.001). Multivariate regression analyses revealed that changes of both, hyperactive-impulsive symptoms (28%) and inattentive symptoms (23%) could be explained by objective changes of motor activity. Thus, for clinical practice, it should be taken into account that behavior ratings of ADHD symptoms seemed to be predominantly influenced by changes of motor activity.

Treatment guidelines for children and adolescents with bipolar disorder

Clinicians who treat children and adolescents with bipolar disorder desperately need current treatment guidelines. These guidelines were developed by expert consensus and a review of the extant literature about the diagnosis and treatment of pediatric bipolar disorders. The four sections of these guidelines include diagnosis, comorbidity, acute treatment, and maintenance treatment. These guidelines are not intended to serve as an absolute standard of medical or psychological care but rather to serve as clinically useful guidelines for evaluation and treatment that can be used in the care of children and adolescents with bipolar disorder. These guidelines are subject to change as our evidence base increases and practice patterns evolve.

Individual change in methylphenidate use in a national sample of children aged 2 to 11 years

OBJECTIVES

To determine methylphenidate use in children aged 2 to 13 years. To provide age- and sex-specific estimates of methylphenidate initiation and cessation during a 2-year period.

METHOD

Data from 2 cycles of a Canadian household survey yielded a sample of over 10 000 children aged 2 to 11 years at Cycle 1 who continued to participate at Cycle 2. We used logit modelling to estimate Cycle 2 methylphenidate use, methylphenidate use over a 2-year period, and methylphenidate initiation and cessation from Cycles 1 to 2.

RESULTS

In 1996 and 1997, methylphenidate use ranged from 0.32% to 6.31% among children aged 4 to 13 years. School-aged boys were more likely than girls to use methylphenidate. Odds were greater for boys aged 6 to 7 years than for boys aged 4 to 5 years; they were also greater for boys aged 10 to 11 years than for boys aged 12 to 13 years. Almost 1% of children used methylphenidate at both data cycles. Odds of Cycle 2 methylphenidate use were 135 times greater for children using methylphenidate at Cycle 1, compared with nonusers. Methylphenidate initiation ranged from 0.20% to 3.34%, and school-aged boys had higher initiation rates than girls. Cessation rates ranged from 18% to78%, and there were no statistically significant differences by age and sex.

CONCLUSIONS

Methylphenidate prevalence findings are consistent with past studies. We found an age-by-sex interaction on methylphenidate use. We also found both continuity and discontinuity in methylphenidate use.

Stimulant drug treatment in childhood-onset schizophrenia with comorbid ADHD: an open-label case series

The administration of psychostimulants to children with psychotic symptoms is controversial. This study reports the stimulant drug response of 5 children, aged 8-15 years, with childhood-onset schizophrenia (COS) and comorbid attention deficit hyperactivity disorder (ADHD). Four COS inpatients were given stimulants for comorbid ADHD after stabilization of psychosis on antipsychotic medication. A fifth COS inpatient received stimulants while still actively psychotic, despite concurrent neuroleptic treatment. Data from the 10-item Brief Conners Teachers Ratings Scale (BCTRS) were examined the week before, and the week after, stimulant addition. A paired t test, conducted using Conners Teachers data from these 4 subjects, indicated significant improvement in ADHD symptoms (p = 0.02). Data obtained from a retrospective chart review indicated no significant worsening of psychosis. The 2 subjects treated with mixed salts of dextroamphetamine sulfate and amphetamine sulfate remained on that medication at 6 months and at the 2-year follow-up. Our results suggest that ADHD comorbid with COS may be safely treated with a stimulant, once the psychosis is stabilized. A systematic investigation of this question may be warranted.

The scientific foundation for understanding attention-deficit/hyperactivity disorder as a valid psychiatric disorder

Continued questioning of the validity of a diagnosis of attention-deficit/hyperactivity disorder (ADHD) has created uncertainties about its management in the minds of many clinicians and the public. Inaccurate beliefs about the validity of ADHD hinder the clinical care of many ADHD patients and lead to confusion about the need to seek out or accept treatment. Critics describe ADHD as a diagnosis used to label difficult children who are not ill but whose behavior is at the extreme end of normal. They further contend that, far from having a biological basis, ADHD results from poor parenting and ineffective teaching practices. Such attitudes do much to further stigmatize patients and their families and increase the burden of this debilitating condition. This review attempts to address these challenges by presenting evidence to show that ADHD meets the criteria for a valid psychiatric diagnosis. Not only does it cause specific disabling symptoms that frequently persist into adulthood, but many studies show it has a biological basis and a characteristic response to treatment. Such data support the idea that ADHD is a valid diagnostic category.

Discriminative stimulus and self-reported effects of methylphenidate, d-amphetamine, and triazolam in methylphenidate-trained humans

Asymmetrical generalization between drugs on drug-discrimination procedures has been demonstrated for sedative and stimulant drugs in animals and to some extent with sedative drugs in humans. The aim of this experiment was to examine the discriminative-stimulus effects of d-amphetamine in methylphenidate-trained humans. A previous study demonstrated that methylphenidate substitutes for d-amphetamine in d-amphetamine-trained humans. Six healthy human participants first learned to discriminate 30 mg oral methylphenidate. Doses of oral methylphenidate, d-amphetamine, triazolam, and placebo were then tested to determine whether they share discriminative-stimulus and self-reported effects with 30 mg methylphenidate. Methylphenidate and d-amphetamine dose-dependently increased methylphenidate-appropriate responding and produced prototypical stimulant-like effects. Triazolam produced low levels of methylphenidate-appropriate responding and prototypical sedative-like effects. The results of this experiment are concordant with previous studies and suggest that the behavioral effects of oral methylphenidate and d-amphetamine overlap extensively and that the discriminative-stimulus effects of methylphenidate and d-amphetamine are symmetrical.

Non-medical use of prescription stimulants among US college students: prevalence and correlates from a national survey

AIMS

To examine the prevalence rates and correlates of non-medical use of prescription stimulants (Ritalin, Dexedrine or Adderall) among US college students in terms of student and college characteristics.

DESIGN

A self-administered mail survey.

SETTING

One hundred and nineteen nationally representative 4-year colleges in the United States.

PARTICIPANTS

A representative sample of 10 904 randomly selected college students in 2001.

MEASUREMENTS

Self-reports of non-medical use of prescription stimulants and other substance use behaviors.

FINDINGS

The life-time prevalence of non-medical prescription stimulant use was 6.9%, past year prevalence was 4.1% and past month prevalence was 2.1%. Past year rates of non-medical use ranged from zero to 25% at individual colleges. Multivariate regression analyses indicated non-medical use was higher among college students who were male, white, members of fraternities and sororities and earned lower grade point averages. Rates were higher at colleges located in the north-eastern region of the US and colleges with more competitive admission standards. Non-medical prescription stimulant users were more likely to report use of alcohol, cigarettes, marijuana, ecstasy, cocaine and other risky behaviors.

CONCLUSIONS

The findings of the present study provide evidence that non-medical use of prescription stimulants is more prevalent among particular subgroups of US college students and types of colleges. The non-medical use of prescription stimulants represents a high-risk behavior that should be monitored further and intervention efforts are needed to curb this form of drug use.

Review and comparison of the long acting methylphenidate preparations

The stimulants have been the mainstay of pharmacologic treatment for over fifty years. Methylphenidate is the most frequently prescribed of the stimulant agents. In the past, one of the main drawbacks of these agents was the abbreviated duration of action. Over the last few years three longer acting methylphenidate preparations have been released to the market. Though all these agents contain the same chemical compound they do vary in a number of ways. In this article we will present how the formulations compare in their technology and the differences in their delivery systems. We will also compare the available literature that focus on head to head comparisons in terms of pharmacokinetics studies and those reports that present efficacy data. Finally, we will suggest based on a theoretical framework on how to approach selecting an agent based on the results of these trials and the individual needs of the patient.

The role of stimulants in the treatment of preschool children with attention-deficit hyperactivity disorder

The symptoms of attention-deficit hyperactivity disorder (ADHD) can have an early onset, beginning before the age of 6 years. Despite the significant number of preschool-aged children that can be diagnosed with ADHD, there are limited controlled data available on the pharmacological interventions being increasingly used in this population. A 1990 review showed that 34% of paediatricians and 15% of family physicians had prescribed psychostimulant medications to preschoolers with ADHD, and pharmacoepidemiological studies indicate growing use of stimulants in preschoolers during the 1990s. Unfortunately, only six controlled trials, with a total enrollment of less than 200 children, have been conducted using these drugs in preschoolers. While these small studies provide some evidence of benefit from the use of methylphenidate in preschoolers with ADHD, more data are critically needed. Practice parameters developed by the American Academy of Child & Adolescent Psychiatry and the American Academy of Pediatrics provide some guidance regarding the diagnosis and treatment of young children with ADHD, but are mainly based upon research in children of primary-school age. The ongoing PATS (Preschool ADHD Treatment Study), funded by the National Institute of Mental Health, will provide important clinical guidance for diagnostic considerations and intervention strategies for children with ADHD aged 3-5 years. Pending the release of data from the PATS study, clinicians must rely on developmental assessment skills, available standardised rating instruments, reports about the child from multiple informants, and knowledge of the risks and benefits of available pharmacological and behavioural treatments, in order to treat preschool children with ADHD effectively.

Altering the course of neurodevelopment: a framework for understanding the enduring effects of psychotropic drugs

Childhood is a time filled with wondrous changes, as brain plasticity permits experiences to shape the immature brain to meet the demands of the environment. Change occurs at various levels--from neuroanatomy, including within a given region and its connectivity to other regions, to the function of neurotransmitter systems and their reactivity to pharmacological agents in the short- and long-term. The nature and degree to which drug exposure influences the final adult topography is influenced greatly by the maturational phase of these critical factors. Moreover, evidence is slowly emerging that suggests that the long-term effects of drug exposure are delayed and expressed once the vulnerable system reaches maturation (i.e., typically during adulthood). This phenomenon is known as neuronal imprinting and occurs when the effects of drug exposure outlast the drug itself. Thus, understanding the persistent effects critically depends on the window of observation. Embracing this concept should influence how we conduct preclinical assessments of developmental drug exposure, and ultimately how we conduct clinical assessments of drug efficacy, effectiveness, and safety for the treatment of childhood psychiatric disorders. In this article, we present a model to provide a heuristic framework for making predictions about imprinted effects of childhood drug exposure. We then review epidemiological data on attention deficit hyperactivity disorder (ADHD) and childhood depression, prescription practices, and what is known regarding the long-term consequences of drug exposure in these populations. We conclude with a discussion of the current status of preclinical studies on juvenile stimulant exposure.

[Pharmacological treatment in adults with attention deficit hyperactivity disorder]

Treatment in adults with attention deficit hyperactivity disorder predominantly relies on pharmacotherapeutic approaches especially with psychostimulants. Empirical studies indicate that their clinical effectiveness may be as high as in children and adolescents, especially in higher dosages. However, due to the high prevalence of comorbidities, e.g. depression, psychopharmacological treatment requires an extended use of other substance groups, especially antidepressants. An optimal treatment response necessitates the choice of an adequate substance depending on the leading clinical symptoms and a procedure of an individual titration of different dosages. This article reviews the current empirical results in the pharmacological treatment of ADHD in adults and provides possible treatment strategies for clinical practice.

Use of stimulants for attention deficit hyperactivity disorder: FOR

Definitive diagnosis of attention deficit hyperactivity disorder is complex. David Coghill believes the condition is undertreated, but Harvey Markovitch argues that current uncertainties about diagnosis and treatment mean doctors should be cautious

Primary care clinicians' use of standardized psychiatric diagnoses

OBJECTIVE

Treatment of child mental health (MH) problems should be informed by psychiatric diagnosis. Whether primary care clinicians (PCCs) use standardized psychiatric diagnostic criteria to direct the treatment of child MH problems is unknown. This study investigated PCCs' use of Diagnostic and Statistical Manual of Mental Disorders (DSM) criteria during office visits.

METHODS

The data were obtained from 3674 children ages 4-15 years who were recognized as having one or more MH problems during office visits by clinicians participating in the Child Behaviour Study. Parents completed questionnaires before seeing the clinician. Clinicians completed a survey after the visit. The primary outcome was whether PCCs used standardized criteria to generate a diagnosis for children with recognized MH problems.

RESULTS

Clinicians used DSM criteria in 23% of visits in which a psychosocial problem was recognized, and 57% of PCCs reported no use of DSM. DSM criteria were used most frequently (38% of visits) when PCCs reported attention problems. Medications were much more likely to be prescribed during visits when PCCs diagnosed using DSM criteria (63% of visits vs. 19% when criteria were not used). However, only 51% of psychotropic medication prescriptions were based on a DSM diagnosis.

CONCLUSIONS

Clinicians used standardized criteria infrequently, and primarily to diagnose attention problems.

A chart review of cyproheptadine for stimulant-induced weight loss

Youths with attention deficit hyperactivity disorder often experience weight loss on stimulants, which may limit optimal dosing and compliance. Cyproheptadine has been shown in medical samples to stimulate weight gain. We conducted a retrospective chart review of 28 consecutive pediatric psychiatry outpatients prescribed cyproheptadine for weight loss or insomnia while on stimulants. Of these, 4 patients never took cyproheptadine consistently, and 3 discontinued it within the first 7 days due to intolerable side effects. Data were analyzed for 21 other patients (age range 4-15 years) who continued with 4-8 mg of cyproheptadine nightly (mean final dose = 4.9 mg/day) for at least 14 days (mean duration = 104.7 days). Most had lost weight on stimulant alone (mean weight loss was 2.1 kg, mean weight velocity was -19.3 g/day). All 21 gained weight taking concomitant cyproheptadine, with a mean gain of 2.2 kg (paired t = 6.87, p < 0.0001) and a mean weight velocity of 32.3 g/day. Eleven of 17 patients who had reported initial insomnia on stimulant alone noted significant improvements in sleep with cyproheptadine added. We conclude that concomitant cyproheptadine may be useful in youths with attention deficit hyperactivity disorder for stimulant-induced weight loss, pending future randomized controlled trials.

The use, misuse and diversion of prescription stimulants among middle and high school students

This present study investigated the prevalence and the factors associated with the use, misuse, and diversion of prescribed stimulant medication for attention-deficit hyperactivity disorder (ADHD) in a sample of middle and high school students. As part of a school-based, self-administered web survey in May 2002, students from a Midwestern public school district in the United States in grades six through eleven (n = 1536) reported on three aspects of prescription stimulants; they reported on their use, misuse, and diversion (e.g. trading, selling, offering) of stimulant medication for ADHD. The total student sample was 57% White, 40% African American, and 3% other racial and ethnic groups. Gender and school level were approximately equally distributed in the student sample, and 81% of students had plans to attend college. The illicit use of stimulant medication was reported by 4.5% of the overall sample. Of the students who reported prescription stimulant use, 23.3% reported being approached to sell, give, or trade their prescription drugs. After adjusting for socio-demographic factors, the odds for illicit use of stimulant medication was lower among African American students and higher among those students with no plans for attending college. When compared with students who did not use stimulants or who did not misuse stimulant medications also reported significantly higher rates of alcohol and other drug use. High schools students had the highest rates of alcohol and other drug use. High schools students had the highest odds for being approached to divert their stimulant medications. Our findings suggest that community-based approaches are needed to reduce the illicit use and diversion of stimulant medications within middle and high school student populations.

Pharmacokinetic considerations in the treatment of attention-deficit hyperactivity disorder with methylphenidate

Methylphenidate is commonly used for the treatment of attention-deficit hyperactivity disorder (ADHD). Its efficacy in improving the core symptoms of ADHD, as well as some of the aggressive and oppositional behaviours, is well documented, based on a large volume of research. Methylphenidate has a wide margin of safety and relatively mild adverse effects, most commonly appetite suppression and insomnia. Methylphenidate is a rapidly absorbed medication that, in its d-isomer form, readily penetrates the CNS, particularly the striatum. It appears to function by blocking the reuptake of dopamine. Both the plasma concentrations and behavioural effects of methylphenidate demonstrate a time to maximum of between 1 and 3 hours, with the maximum behavioural effects occurring when the plasma concentrations are increasing. Because of the rapid onset of action, the effects of methylphenidate can be dramatic but usually last only about 4 hours with the immediate-release formulation. The behavioural responses of individuals are also highly variable, so that it is necessary to start treatment at a low dosage and increase up to a maximally effective dosage (usually starting at 10-15 mg/day with increases of 10-15mg at weekly intervals to a maximum dosage of 60 mg/day, irrespective of formulation). Because of the variability in behavioural responses, assessment of plasma concentrations is not clinically useful nor does weight help in deciding an appropriate dosage. The difficulties in administering methylphenidate multiple times a day, particularly during the school day, have been alleviated in the past few years by the development of extended-release preparations with varying behavioural effects lasting 8-12 hours. The 8-hour preparations (Metadate) CD and Ritalin) LA) utilise a microbead technology, while the 12-hour preparation (Concerta) utilises an osmotic pump system. All extended-release formulations effectively control the symptoms of ADHD. While pharmacokinetic differences appear to exist between some of these new formulations, there are currently no clinical data available to demonstrate clinical efficacy differences between them.

National trends in concomitant psychotropic medication with stimulants in pediatric visits: practice versus knowledge

OBJECTIVES

(1) To examine U.S. national trends in the use of concomitant pharmacotherapy with the stimulant class of psychotropic drugs in youth; and (2) to present these trends in the context of (a) extant safety and efficacy data, and (b) overall trends in concomitant pharmacotherapy with psychotropic drugs for youth.

METHODS

Prescribing data for youths under age 18 years from National Ambulatory Medical Surveys from 1993 to 1998 were analyzed. The visits were categorized into monotherapy (only one psychotropic prescribed) and concomitant pharmacotherapy (>1 psychotropic prescribed). The proportions of these groups were computed as a percentage of all visits during which a psychotropic medication was prescribed. Differences in proportions between surveys were analyzed to determine trends.

RESULTS

Between 1993--94 and 1997--98, the proportions of visits for concomitant pharmacotherapy in association with the stimulant class increased nearly five-fold. This increase paralleled an overall increase in the proportion of visits involving prescription of more than one psychotropic medication among youth.

CONCLUSIONS

The growth in concomitant pharmacotherapy with the stimulants class has out-paced the increase in safety/efficacy data to inform the use of this practice, resulting in a mismatch between trends in prescribing and growth in knowledge. A simultaneous trend of note is the overall increase in the use of concomitant pharmacotherapy with all psychotropic drugs in youth. Controlled trials are particularly needed to support commonly used combinations of stimulants with antidepressants in youth. In the absence of definitive data, clinical guidelines based on expert consensus and limited data are available and are useful.

Effects of once-daily osmotic-release methylphenidate on blood pressure and heart rate in children with attention-deficit/hyperactivity disorder: results from a one-year follow-up study

OBJECTIVE

Studies of vital signs in children and adolescents with attention-deficit/hyperactivity disorder (ADHD) receiving stimulants indicate a variable effect on blood pressure (BP) and heart rate (HR). We evaluated the longer-term effects on vital signs of once-daily osmotic-release methylphenidate (MPH, Concerta) in children with ADHD.

METHODS

As part of a 1-year open-extension trial, we studied children with ADHD (aged 6-13 years; baseline assessment, n = 432) who were entered into an open-label study of osmotic-release MPH (18-54 mg) for up to 1 year. Subjects' BP and HR were recorded at monthly visits and, when applicable, analyses were by last observation carried forward.

RESULTS

Compared to off-drug baseline, osmotic-release MPH was associated with minor clinical, although statistically significant, changes in systolic and diastolic blood pressure (DBP) (3.3 and 1.5 mm Hg, Ps < 0.001) and HR (3.9 bpm, P < 0.0001) at 12-month end point. There was no clear dose-response relationship. There was no tolerance to the pressor effects of osmotic-release MPH over the 1-year period. There was an inverse relationship between baseline vital signs and positive change in vital signs at end point.

CONCLUSIONS

Over a 12-month period, osmotic-release MPH produced minor clinical, although statistically significant, changes in BP and HR in children with ADHD.

Meta-analysis of the efficacy of methylphenidate for treating adult attention-deficit/hyperactivity disorder

This article reviews the efficacy of methylphenidate (MPH) for adult attention-deficit/hyperactivity disorder (ADHD). A literature search identified double-blind placebo-controlled MPH treatment studies of ADHD adults. Meta-analysis estimated the pooled effect size for MPH treatment and tested for publication bias. Meta-analysis regression assessed the influence of study design features on medication effects. Six trials met criteria and were included in this meta-analysis. These studies included a total of 140 MPH-treated ADHD adults and 113 placebo-treated ADHD adults. The mean effect size of 0.9 was statistically significant and there was no evidence of publication bias. Larger MPH effect sizes were associated with physician ratings of outcome and use of higher doses. When treatment is optimized to high doses, the effect size for MPH in adults was 1.3. We found strong support for the assertion that MPH is efficacious for treating adult ADHD. Because the degree of efficacy of MPH in treating ADHD adults is similar to what has been reported from meta-analyses of the child and adolescent literature, our work provides further assurance to clinicians that the diagnosis of ADHD can be validly applied in adulthood.

Les traitements médicaux de l’enfant hyperactif

Treatment of hyperactive child is multimodal, a combination of behaviour therapy and medication. Stimulant drugs are the most often prescribed medications. In France, we use methylphenidate (Ritaline); its efficacy was demonstrated with mild side effects. New formulations of methylphenidate with prolonged action, and non-psychostimulant treatment (atomoxetine) are available in some countries, but not yet in France.

Association of cortical disinhibition with tic, ADHD, and OCD severity in Tourette syndrome

Hyperkinetic disorders may involve excess excitatory output from thalamus to cerebral cortex. Case-control, neurophysiological studies in persons with Tourette Syndrome (TS), Attention Deficit Hyperactivity Disorder (ADHD), and Obsessive-Compulsive Disorder (OCD) support this model. To compare the strength of association between motor cortex inhibition and tic, ADHD, and OCD severity in TS, we used transcranial magnetic stimulation to measure motor cortex inhibition in 36 children and adults with TS. Current symptom severity was assessed with standard clinical rating scales and compared with neurophysiological measures using correlational and multivariate regression analyses. Severity of ADHD symptoms and motor tics were associated significantly and independently with short interval intracortical inhibition (SICI) (r(2) = 0.50; F[2,27] = 13.7; P < 0.001), particularly in subjects not taking neuroleptics (r(2) = 0.68; F[2,17] = 17.8; P < 0.0001). The correlation of cortical disinhibition was greater with ADHD symptoms severity (r = 0.53; P = 0.003) than with tic severity (r = 0.42; P = 0.02), suggesting that in TS, the association between SICI and ADHD symptoms may be more consistent or direct than the association between SICI and tics.

Methylphenidate treatment during pre- and periadolescence alters behavioral responses to emotional stimuli at adulthood

BACKGROUND

Methylphenidate (MPH) is a psychomotor stimulant medication widely used for the treatment of attention-deficit/hyperactivity disorder (ADHD). Given the extent of prescribed use of MPH, and because MPH interacts with the same brain pathways activated by drugs of abuse, most research has focused on assessing MPH's potential to alter an individual's risk for adult drug addiction. Data examining other potential long-term behavioral consequences of early MPH administration are lacking, however.

METHODS

We investigated the long-term behavioral consequences of chronic administration of MPH (2.0 mg/kg) during pre- and periadolescent development in adult rats by assessing their behavioral reactivity to a variety of emotional stimuli.

RESULTS

The MPH-treated animals were significantly less responsive to natural rewards such as sucrose, novelty-induced activity, and sex compared with vehicle-treated control animals. In contrast, MPH-treated animals were significantly more sensitive to stressful situations, showed increased anxiety-like behaviors, and had enhanced plasma levels of corticosterone.

CONCLUSIONS

Chronic exposure to MPH during development leads to decreased sensitivity to rewarding stimuli and results in enhanced responsivity to aversive situations. These results highlight the need for further research to improve understanding of the effects of stimulants on the developing nervous system and the potential enduring effects resulting from early-life drug exposure.

A dose-response study of OROS methylphenidate in children with attention-deficit/hyperactivity disorder

OBJECTIVE

OROS methylphenidate HCL (MPH) is a recently developed long-acting stimulant medication used to treat attention-deficit/hyperactivity disorder (ADHD). This study was conducted to examine dosage effects on ADHD symptoms and stimulant side effects and to explore potential moderating effects of ADHD subtype.

METHODS

Children with ADHD combined type (ADHD-CT) or predominantly inattentive type (ADHD-PI; n = 47), ages 5 to 16 years, underwent a placebo-controlled, crossover trial using forced titration with weekly switches at 3 dosage levels. Parent and teacher ratings of ADHD symptoms were used to evaluate efficacy. In addition, vital signs and standardized measures of stimulant side effects were obtained weekly.

RESULTS

Parent ratings were more sensitive to treatment effects than teacher ratings. ADHD symptoms and Clinical Global Impressions Severity Index ratings at each dose condition differed significantly from placebo and baseline ratings, which did not differ from one another. For those with ADHD-CT, there was a clear linear dose-response relationship, with clinically significant reductions in ADHD Rating Scale-IV scores occurring in two thirds to three fourths of the subjects during either 36- or 54-mg dose conditions. Children with ADHD-PI, conversely, were more likely to respond optimally to lower doses and derived less benefit from higher doses, with 60% displaying significant improvement on the ADHD Rating Scale-IV at 36 mg or lower. Mild stimulant side effects were reported during placebo and at all dosage levels. With the exception of insomnia and decreased appetite, which were more common at higher doses, parent report of side effects was not related to dose. In addition, younger and smaller children were more likely to display sleep difficulties and decreased appetite at the higher dose levels Although pulse rate increased slightly with increasing dose, there were no dose effects on blood pressure.

CONCLUSIONS

In children with ADHD-CT, the most common subtype of ADHD, increasing doses of stimulant medication were associated with increased improvement of inattention and hyperactivity symptoms. In children with ADHD-PI, symptom improvement occurred at lower doses and less benefit was derived from higher doses. In both ADHD subtypes, higher doses were associated with parent ratings of increased insomnia and decreased appetite.

Advances in the Pharmacotherapy of Attention-Deficit–Hyperactivity Disorder: Focus on Methylphenidate Formulations

The psychostimulant dl-methylphenidate (MPH) remains the most common drug therapy in child and adolescent psychiatry for the treatment of attention-deficit-hyperactivity disorder (ADHD). Evidence of a dopaminergic basis both for the actions of MPH and for the underlying neuropathology in ADHD continues to mount. Advances in the biopharmaceutics of MPH have been conspicuous. Novel approaches to formulation design have resulted in new MPH delivery options to overcome the short-term actions of both immediate-and sustained-release MPH. New modified-release MPH products offer the convenience of once-daily administration while providing extended absorption profiles that better mimic those of standard schedules of immediate-release MPH (i.e., the absorption phase of MPH better correlates with improved behavioral response than does the elimination phase). The oral bioavailability of MPH in females may be lower than in males. The l-MPH isomer exhibits only negligible oral bioavailability and, further, possesses little intrinsic activity at the dopamine transporter. This notwithstanding, a single-isomer d-MPH immediate-release product is now available for dosing recommended at one-half that of dl-MPH.

A pharmacokinetic/pharmacodynamic study comparing a single morning dose of adderall to twice-daily dosing in children with ADHD

OBJECTIVE

To determine the pharmacokinetic and pharmacodynamic properties of once-daily versus twice-daily doses of Adderall.

METHOD

Following a 1-week wash-out, 12 subjects with attention-deficit/hyperactivity disorder (ADHD) entered a double-blind crossover study comparing two conditions: QD (10 mg of Adderall at 7:30 a.m. and placebo at noon) or BID (10 mg of Adderall at 7:30 a.m. and at noon). At two sites, cohorts of six subjects each were assessed on two different days by a 12-hour laboratory school protocol. Plasma concentrations of d- and l-amphetamine, vital signs, teacher ratings of classroom behavior on the SKAMP, and 10-minute Math Test performance were measured repeatedly over 12 hours. An analysis of variance used center, subject-within-center, condition, and time-after-second-dose as independent variables.

RESULTS

The pharmacokinetic profiles revealed similar morning concentrations of d- and l-amphetamine. However, concentrations were twice as high in the afternoon for BID as QD. The two conditions showed similar pharmacodynamic profiles in the morning, although improvement in math performance and behavior was maintained into the afternoon only in the BID condition (p <.05).

CONCLUSIONS

This study suggests that twice-daily dosing of Adderall may be an effective strategy for afternoon control of attention and deportment for children with ADHD.

Attention-deficit/hyperactivity disorder in children and adolescents: interventions for a complex costly clinical conundrum

Management of a child or adolescent with attention-deficit/hyperactivity disorder (ADHD) is reviewed, including psychological and pharmacologic approaches. Psychological treatment includes psychotherapy, cognitive-behavior therapy, support groups, parent training, educator/teacher training, biofeedback, meditation, and social skills training. Medications are reviewed that research has revealed can improve the core symptomatology of a child or adolescent with ADHD. These medications include stimulants, antidepressants, alpha-2 agonists, and a norepinephrine reuptake inhibitor. Management of ADHD should include a multi-modal approach, involving appropriate educational interventions, appropriate psychological management of the patient (child or adolescent), and judicious use of medications. Parents, school officials, and clinicians must work together to help all children and adolescents with ADHD achieve their maximum potential.

Is attention deficit hyperactivity disorder over-represented among HIV-seronegative boys with haemophilia? Preliminary results from our centre

Haemophilia care providers report anecdotally that many boys under their care bear the diagnosis of attention deficit hyperactivity disorder (ADHD). This study investigated the hypothesis that ADHD is over-represented among boys with haemophilia. All the boys with haemophilia, aged 5-14 years, who receive their comprehensive care at our centre were solicited to participate in this study. Of the 78 eligible boys, 34 (44%) were successfully contacted and agreed to participate. All participants were HIV-negative on both serological and PCR-based assays. The presence of ADHD symptoms was established via a parent- and teacher-completed standardized rating instrument. On the parent-rating scale, 26% of the participants exceeded the cut-off for inattentive ADHD, 18% for hyperactive/impulsive ADHD, and 18% for combined. On the teacher rating scale, 4% of the participants exceeded the cut-off for inattentive ADHD, but no participants were rated as having extreme hyperactive/impulsive or combined ADHD symptoms. Retrospectively, 29% of the participants had previously been diagnosed with ADHD, all treated with stimulant medications. Of note, 38% of our participants were enrolled in special education programmes. All of the above were more common in boys with haemophilia compared with national controls. A chart review of non-participating patients from the same clinic suggested that sampling bias is unlikely to account for these differences. These results provide the first empirical evidence that ADHD may be over-represented among boys with haemophilia.

High-dose methylphenidate treatment of attention deficit hyperactivity disorder in a preschooler

Although attention deficit hyperactivity disorder is thought to be present in preschoolers, there are no clear guidelines for dosing stimulant medications in this population. This is a case of a 4-year-old boy who was given 108 mg/day extended-release methylphenidate (OROS) MPH) (6.1 mg/kg/day) by his caregiver with notable behavioral improvement. However, weight loss incurred due to the anorexic side effect of the medication led the clinician to decrease his dose to 72 mg/day OROS MPH (3.7 mg/kg/day). The case highlights that some young children with attention deficit hyperactivity disorder treated with MPH may require higher doses than would be predicted by weight-based dosing. An increased frequency of side effects associated with high doses of MPH necessitates that the clinician balance the positive behavioral response of the medication with adverse side effects in determining ideal dose.

Selective inhibition in children with attention-deficit hyperactivity disorder off and on stimulant medication

Selective inhibition requires discrimination between auditory signals and is assessed using a modification of the stop-signal task. Selective inhibition was assessed in a group of 59 clinic-referred, DSM-IV-diagnosed children with attention-deficit hyperactivity disorder (ADHD) and compared to that of a community sample of 59 children. Methylphenidate (MPH) effects on selective inhibition were assessed in a subset of the ADHD sample that participated in an acute, randomized, placebo-controlled, crossover trial with 3 fixed doses of MPH. Children with ADHD performed more poorly than controls on the majority of selective stop-signal task parameters: they exhibited more anticipatory (invalid) responses, with less accurate and more variable responses on the response execution task, as well as a slower selective inhibition process. MPH improved speed of both inhibition and response execution processes; it also reduced variability of response execution and decreased nonselective inhibition. On the one hand, findings are consistent with purported inhibition deficit in ADHD, but on the other hand, suggest that neither the impairment itself, nor MPH effects, were restricted to inhibition.

Guidelines and algorithms for the use of methylphenidate in children with Attention-Deficit/ Hyperactivity Disorder

OBJECTIVE

To review published algorithms for guiding the use of methylphenidate (MPH) in the treatment of Attention-Deficit/Hyperactivity Disorder (ADHD) in children and adolescents.

METHODS

A consensus roundtable of 12 experts was convened to review the evidence for the safety and efficacy of MPH in the treatment of ADHD, as well as the published algorithms and practice guidelines for using MPH. The experts reviewed the algorithms for practicality and acceptability by clinicians.

RESULTS

Algorithms that included MPH commonly selected it as the initial medication to be employed in the treatment of children with ADHD. Factors involved included its high efficacy, good safety record, and the ubiquitous nature of its appearance in the ADHD treatment literature.

CONCLUSIONS

MPH should be considered as the first medication to be used in a treatment algorithm for children and adolescents with ADHD.

Compliance with stimulants for attention-deficit/hyperactivity disorder: issues and approaches for improvement

Attention-deficit/hyperactivity disorder (ADHD) affects approximately 8-10% of school-aged children in the US and for many individuals persists into adolescence and adulthood. Both pharmacological and nonpharmacological (behavioural) therapies are used to treat individuals with ADHD. Treatment with stimulant medications, which include methylphenidate and amphetamine, typically requires multiple daily doses to maintain efficacy. The frequency of treatment, coupled with the importance of timing of doses and the long-term nature of treatment, make noncompliance a particular issue in the treatment of ADHD. Studies report noncompliance rates of 20-65% with stimulant treatment, although there are only limited published studies and these show considerable individual variation. Noncompliance can arise through inadequate supervision of those receiving medication, leading to delayed or missed doses, or through the reluctance of individuals to take medication, which is influenced by a number of factors (e.g. social attitudes, pressures or worries surrounding medication use and the inconvenience of multiple daily doses). Two approaches are likely to increase compliance with stimulant treatment: effective once-daily formulations of medication and improved treatment information. The development of effective once-daily formulations for stimulant treatments removes the need for multiple daily doses, with the associated problems of ensuring adequate treatment supervision and personal privacy. Improved provision of education and information for individuals with ADHD, as well as their families and teachers, should help them address the issues surrounding stimulant medication and allow full participation in the treatment process. Together, these strategies should improve treatment compliance for individuals with ADHD.

Cardiovascular effects of methylphenidate in humans are associated with increases of dopamine in brain and of epinephrine in plasma

RATIONALE

The cardiovascular effects of psychostimulant drugs (methylphenidate, amphetamine, cocaine) have been mostly associated with their noradrenergic effects. However, there is some evidence that dopaminergic effects are involved in the cardiovascular actions of these drugs. Here, we evaluated this association in humans.

METHODS

Positron emission tomography (PET) and [(11)C]raclopride, a dopamine (DA) D2 receptor radioligand that competes with endogenous DA for occupancy of the D2 receptors, were used to measure changes in brain DA after different doses of intravenous methylphenidate in 14 healthy subjects. Cardiovascular (heart rate and blood pressure) and catecholamine (plasma epinephrine and norepineprhine) responses were determined in parallel to assess their relationships to methylphenidate-induced changes in brain DA.

RESULTS

Methylphenidate administration significantly increased heart rate, systolic and diastolic blood pressures and epinephrine concentration in plasma. The increases in blood pressure were significantly correlated with methylphenidate-induced increases of DA in striatum (r>0.78, P<0.001) and of plasma epinephrine levels (r>0.82, P<0.0005). In turn methylphenidate-induced DA increases in striatum were correlated with increases of epinephrine in plasma (r=0.85, P<0.0001). Subjects in whom methylphenidate did not increase DA had no change in blood pressure or in plasma epinephrine concentration.

DISCUSSION

These results are consistent with the hypothesis that methylphenidate-induced increases in blood pressure are in part due to its central dopaminergic effects. They also suggest that methylphenidate's pressor effects may be in part mediated by DA-induced increases in peripheral epinephrine.

Is primary care ready to take on Attention Deficit Hyperactivity Disorder?

BACKGROUND

Attention Deficit Hyperactivity Disorder (ADHD) is a common childhood psychiatric disorder. The management of ADHD has recently been highlighted. The National Institute of Clinical Excellence (NICE) and Scottish Intercollegiate Guidelines network (SIGN) have both produced management guidelines. Doctors working within Primary Care in countries such as the United States play an important role in the management of ADHD. In the United Kingdom however the role of doctors in primary care in the management of ADHD, both individually and within shared care protocols, is only now being identified and defined. Is this role for Primary Care likely to be acceptable and effective?

DISCUSSION

There is some evidence that doctors working within Primary Care in the United Kingdom are willing to follow up children on medication for ADHD and carry out monitoring of physical status. However many feel unconfident in the management of ADHD and most have received little or no training in child psychiatry. There are also concerns that adverse media reports will have an undue influence on the attitudes of doctors within primary care to families with children suffering from ADHD.

SUMMARY

There are important barriers to be tackled before shared care protocols for ADHD can be successfully implemented in the United Kingdom. Tailored information about ADHD needs to be provided to doctors in primary care. Clear dialogue between planners and healthcare professionals from both primary and secondary care is essential to ensure that service delivery is acceptable to healthcare providers, tailored to their skills and is adequately resourced.

A postmarketing clinical experience study of Metadate CD

OBJECTIVE

The objective of the study was to investigate the effectiveness and safety of Metadate CD (methylphenidate HCl, USP) Extended Release Capsules in the treatment of Attention-Deficit/Hyperactivity Disorder (ADHD), in actual clinical practice.

METHOD

This was a multicenter, open-label, postmarketing study. Eligible patients were aged 6-17 with a diagnosis of ADHD and receiving either no treatment or maintenance treatment with another approved methylphenidate (MPH) product. Metadate CD was administered once daily for 3 weeks, titrated against reported and observed symptoms. Clinical Global Impression (CGI) scores at Week 3 were used for the primary efficacy evaluation. Patient treatment satisfaction was determined by questionnaire at the final evaluation visit. Safety was assessed through adverse event reporting, laboratory tests and vital sign measurements.

RESULTS

Overall, of the 308 patients in the Intent-To-Treat population, the majority (65%) demonstrated a positive response to Metadate CD (defined as CGI Global Improvement rating of very much or much improved). In addition, patients previously treated with immediate-release or extended-release tablet formulations of MPH were successfully converted to Metadate CD at a comparable dose. Most patients (87%) were very satisfied or moderately satisfied with study treatment, and among previously treated patients, 71% rated Metadate CD as much better or better than their previous MPH treatment. Adverse events were consistent with current FDA-approved product labeling for Metadate CD.

CONCLUSIONS

Metadate CD is effective and well-tolerated in actual clinical use for ADHD.