Titrating Optimal Dose of Osmotic-Controlled Release Oral Delivery (OROS)-Methylphenidate and Its Efficacy and Safety in Korean Children with ADHD: A Multisite Open Labeled Study

Evaluation of Methylphenidate Safety and Maximum-Dose Titration Rationale in Attention-Deficit/Hyperactivity Disorder: A Meta-analysis

IMPORTANCE

Evidence on the titration of stimulant medications for attention-deficit/hyperactivity disorder (ADHD) is lacking. However, this lack of evidence has not prevented medication guidelines from specifying apparently arbitrary dose limitations, which could discourage clinicians from titrating methylphenidate to higher and, perhaps for some patients, more efficacious doses.

OBJECTIVE

To determine the evidence on dose titration and adverse events associated with dose titration of stimulants for ADHD.

DATA SOURCES

MEDLINE from 1946, Embase from 1974, and PsycINFO from 1806 through April 1, 2019, were searched to identify relevant articles.

STUDY SELECTION

The inclusion criteria were that (1) the study was conducted on children up to 18 years of age; (2) children had a diagnosis of ADHD according to the Diagnostic and Statistical Manual of Mental Disorders, or hyperkinetic disorder according to the International Classification of Diseases codes; and (3) the dose of methylphenidate was determined by titration.

DATA EXTRACTION AND SYNTHESIS

The PRISMA guidelines for abstracting data and assessing data quality and validity were followed. Quality assessment was undertaken using the Jadad scoring system. Statistical analysis was undertaken using a random-effects model.

MAIN OUTCOMES AND MEASURES

The outcomes of interest were (1) the doses used in published clinical trials, (2) the clinical justification given by researchers for their selected dose range, and (3) the adverse effects associated with methylphenidate when the dose is established by titration.

RESULTS

A total of 11 randomized clinical trials and 38 cohort studies were analyzed. The randomized clinical trials involved 1304 participants treated with methylphenidate and 887 controls; the 38 cohort studies included 5524 participants. Maximum doses of methylphenidate ranged from 0.8 to 1.8 mg/kg/d. Some studies detailed their method of titration, including starting dose, titration interval, increment dose, and maximum dose. Not all of these studies reported justification for the chosen dose range. Common adverse effects of methylphenidate included insomnia (odds ratio, 4.66; 95% CI, 1.99-10.92; P < .001), anorexia (5.11 higher than for those who took placebo; 95% CI, 1.99-13.14; P < .001), abdominal pain (1.9 times more likely; 95% CI, 0.77-4.77; P = .16), and headache (14% of participants; 95% CI, 10%-20%; P < .001).

CONCLUSIONS AND RELEVANCE

A range of maximum doses for methylphenidate was recommended in clinical studies; no discernable scientific justification for any particular dose was given. Reports of life-threatening adverse events were absent; further studies of the efficacy, tolerability, and safety of methylphenidate titrated purely on clinical grounds, without reference to any set maximum dose, are needed.

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

BACKGROUND

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

OBJECTIVES

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

SEARCH METHODS

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

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

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

AUTHORS' CONCLUSIONS

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

Remission Rate and Functional Outcomes During a 6-Month Treatment With Osmotic-Release Oral-System Methylphenidate in Children With Attention-Deficit/Hyperactivity Disorder

Many definitions have been used to evaluate remission in patients with attention-deficit/hyperactivity disorder (ADHD) in different studies resulting with varied remission rates. This open-label, multicenter study investigated the remission rate in Chinese children (n = 239; aged 6-16 years) with a diagnosis of ADHD (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition), treated with osmotic-release oral-system methylphenidate at doses of 18, 36, and 54 mg, once daily. Two definitions of remission were used: (1) (primary end point): average scores of SNAP-IV (Swanson, Nolan, and Pelham, Fourth Edition) items of 1 or less (0-3 rating scale for each item) according to the subtype of ADHD (inattentive [1-9], hyperactive-impulsive [10-18], and combined type [1-18]), and (2) total score of SNAP-IV items 1 to 18 of 18 or less, at week 8. The study consisted of screening/baseline, titration/open-label treatment (8 weeks), and extended observation (up to 24 weeks) phases. Secondary efficacy assessments were Clinical Global Impression-Improvement (clinical efficacy), Behavior Rating Inventory of Executive Function Scale (BRIEF; executive function behaviors), and Weiss Functional Impairment Rating Scale (social function). Validity of remission was assessed by comparing the function measures (BRIEF and Weiss's) between patients who achieved remission and those who did not. At week 8, 69.3% (151/218) of patients achieved remission by definition 1, and 73.2% (161/220) by definition 2. At weeks 8 and 24, the remission group had significantly lower BRIEF, Weiss's, and Clinical Global Impression-Improvement scores (P < 0.001 for all) compared with the nonremission group. Overall, treatment with osmotic-release oral-system methylphenidate was well tolerated, with increased remission rates in children with ADHD.

The Effect of Methylphenidate on Neurological Soft Signs in ADHD

OBJECTIVE

Neurological soft signs are very common in children with the attention deficit hyperactivity disorder (ADHD), and the first line medication of this disorder is methylphenidate. The aim of the study was to assess the effect of methylphenidate on the neurological soft signs in children and adolescents suffering from ADHD depending on the dose of methylphenidate.

METHODS

Thirty five patients with ADHD were investigated by the ADHD RS-IV parent version questionnaire and the Revised Neurological Examination for Subtle Signs before treatment adjustment and after four weeks of methylphenidate medication. The changes in hyperactivity symptomatology, neurological soft signs during therapy and the influence of the methylphenidate dose were statistically analyzed.

RESULTS

A significant decrease in hyperactivity symptomatology was found after one month of methylphenidate medication (p=0.0001) and significant decrease in neurological soft signs was demonstrated in 21 from a total of 26 items (p<0.05). Correlation analysis showed no relationship between the dose of methylphenidate and the improvement of neurological soft signs. Similarly, the improvement of ADHD symptomatology had not correlation with the improvement of neurological soft signs.

CONCLUSION

The study demonstrated the positive effect of methylphenidate on neurological soft signs in which improvement occurred independently of the dose, indicating that their progress may be due to methylphenidate treatment of any dose. The unrelated effect of methylphenidate on the attention deficit hyperactivity disorder and neurological soft signs suggest that methylphenidate might be useful in the therapy of clumsy child syndrome and in ADHD treatment of non-responders.

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

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

Effect of methylphenidate treatment on appetite and levels of leptin, ghrelin, adiponectin, and brain-derived neurotrophic factor in children and adolescents with attention deficit and hyperactivity disorder

OBJECTIVES

We aimed to explore whether the use of methylphenidate relates leptin, ghrelin, adiponectin, and brain-derived neurotrophic factor (BDNF). In addition, the relationship between methylphenidate-related weight loss in attention deficit hyperactivity disorder (ADHD) patients and these biomolecules were evaluated.

METHODS

Thirty ADHD patients receiving methylphenidate and 20 healthy controls were included. Leptin, ghrelin, adiponectin, and BDNF levels were measured at baseline and after two-month treatment in both groups.

RESULTS

At baseline, leptin, ghrelin, adiponectin, and BDNF levels were similar in the ADHD and control groups. The most common adverse events occurring in the ADHD group after a 2-month treatment period included loss of appetite (70%) and weight loss (66.7%). A significant difference was found in body weight, BMI, and CGI scores of the ADHD patients after the treatment. While post-treatment ghrelin and adiponectin levels were significantly higher in the ADHD group, BDNF level was significantly lower. Post-treatment decrease in leptin levels was not significant.

CONCLUSIONS

Leptin and BDNF were not associated with poor appetite and/or weight loss due to methylphenidate treatment. However, ghrelin and adiponectin might be biomolecules that play a role in underlying neurobiological mechanisms of methylphenidate-related appetite or weight loss.