Effects of Discontinuing Methylphenidate on Strengths and Difficulties, Quality of Life and Parenting Stress

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

BACKGROUND

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

OBJECTIVES

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

SEARCH METHODS

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 In addition, we checked reference lists and requested published and unpublished data from manufacturers of methylphenidate.

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

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

PRIMARY OUTCOMES

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

SECONDARY OUTCOMES

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

AUTHORS' CONCLUSIONS

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

Association of Attention-Deficit/Hyperactivity Disorder Diagnosis With Adolescent Quality of Life

IMPORTANCE

Appropriate diagnosis of attention-deficit/hyperactivity disorder (ADHD) can improve some short-term outcomes in children and adolescents, but little is known about the association of a diagnosis with their quality of life (QOL).

OBJECTIVE

To compare QOL in adolescents with and without an ADHD diagnosis.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study followed an emulated target trial design using prospective, observational data from the Longitudinal Study of Australian Children, a representative, population-based prospective cohort study with biennial data collection from 2006 to 2018 with 8 years of follow-up (ages 6-7 to 14-15 years). Propensity score matching was used to ensure children with and without ADHD diagnosis were well matched on a wide range of variables, including hyperactive/inattentive (H/I) behaviors. Eligible children were born in 1999 to 2000 or 2003 to 2004 and did not have a previous ADHD diagnosis. All incident ADHD cases were matched with controls. Data were analyzed from July 2021 to January 2022.

EXPOSURES

Incident parent-reported ADHD diagnosis at age 6 to 7, 8 to 9, 10 to 11, 12 to 13, or 14 to 15.

MAIN OUTCOMES AND MEASURES

Quality of life at age 14 to 15 was measured with Child Health Utility 9D (CHU9D) and 8 other prespecified, self-reported measures mapped to the World Health Organization's QOL domains. Pooled regression models were fitted for each outcome, with 95% CIs and P values calculated using bootstrapping to account for matching and repeat observations.

RESULTS

Of 8643 eligible children, a total of 393 adolescents had an ADHD diagnosis (284 [72.2%] boys; mean [SD] age, 10.03 [0.30] years; mean [SD] H/I Strengths and Difficulties Questionnaire score, 5.05 [2.29]) and were age-, sex-, and H/I score-matched with 393 adolescents without ADHD diagnosis at time zero. Compared with adolescents without diagnosis, those with an ADHD diagnosis reported similar QOL on CHU9D (mean difference, -0.03; 95% CI, -0.07 to 0.01; P = .10), general health (mean difference, 0.11; 95% CI, -0.04 to 0.27; P = .15), happiness (mean difference, -0.18; 95% CI, -0.37 to 0.00; P = .05), and peer trust (mean difference, 0.65; 95% CI, 0.00 to 1.30; P = .05). Diagnosed adolescents had worse psychological sense of school membership (mean difference, -2.58; 95% CI, -1.13 to -4.06; P < .001), academic self-concept (mean difference, -0.14; 95% CI, -0.02 to -0.26; P = .02), and self-efficacy (mean difference, -0.20; 95% CI, -0.05 to -0.33; P = .007); displayed more negative social behaviors (mean difference, 1.56; 95% CI, 0.55 to 2.66; P = .002); and were more likely to harm themselves (odds ratio, 2.53; 95% CI, 1.49 to 4.37; P < .001) than adolescents without diagnosis.

CONCLUSIONS AND RELEVANCE

In this cohort study, ADHD diagnosis was not associated with any self-reported improvements in adolescents' QOL compared with adolescents with similar levels of H/I behaviors but no ADHD diagnosis. ADHD diagnosis was associated with worse scores in some outcomes, including significantly increased risk of self-harm. A large, randomized clinical trial with long-term follow-up is needed.

Withdrawing methylphenidate in relation to serum levels of ferritin and zinc in children and adolescents with attention-deficit/hyperactivity disorder

Iron and zinc have been associated with attention-deficit/hyperactivity disorder (ADHD), executive functioning, and response to methylphenidate, given their link with the dopaminergic system. This study aimed to investigate the effect of withdrawing methylphenidate after long-term treatment on serum levels of ferritin and zinc; and if baseline (pre-discontinuation) serum levels of these nutritional markers moderated the effects of withdrawing methylphenidate on ADHD and oppositional defiant disorder (ODD) symptoms, and working memory. Blood samples were collected from 63 children and adolescents who participated in a randomized, placebo-controlled methylphenidate discontinuation study. They were assigned to either seven weeks of continued treatment with methylphenidate or to gradual withdrawal to placebo. With mixed models for repeated measures we (i) compared changes in ferritin and zinc serum levels between both groups, and (ii) investigated moderating effects of ferritin and zinc on the effects of discontinuation on ADHD and ODD symptoms, and working memory. We additionally explored correlations of baseline and change serum levels with respective symptom scores. Withdrawing methylphenidate led to a decrease in ferritin levels. Higher baseline ferritin was associated with a larger increase (i.e., worsening) of teacher-rated hyperactivity-impulsivity and ODD symptoms after withdrawal; and higher baseline zinc with a larger increase in number of errors on the working memory task after withdrawal. Serum levels did not correlate with ADHD and ODD symptoms. Our preliminary results suggest that ferritin and zinc may be potential biomarkers for the effectiveness of long-term treatment with methylphenidate.

Self-management training vs. neurofeedback interventions for attention deficit hyperactivity disorder: Results of a randomized controlled treatment study

OBJECTIVES

Neurofeedback (NF) and self-management training (SMT) may be viable treatment options for patients with attention deficit hyperactivity disorder (ADHD) if they alleviate core symptoms, enhance the patients' self-concept and improve their quality of life (QoL). Aim of the current study is evaluating both interventions accordingly and to test whether specific improvements in core symptoms lead to more general improvements in self-concept and QoL.

METHODS

In a psychotherapeutic outpatient clinic in Germany, a total of N = 139 children with ADHD were screened for eligibility, of which 111 fulfilled inclusion criteria and participated in the study in accordance with the CONSORT 2010 statement. These were randomly assigned to NF vs. SMT interventions. Changes from pre- to post-intervention in core ADHD symptoms relying on parent and teacher reports (CONNERS 3) and objective tests (Qb-Test) as well as self-concept (interview with the children) and QoL assessments (using the KINDL-R self-report) were compared between patients receiving NF or SMT.

RESULTS

Significant improvements in ADHD symptoms were achieved similarly in both treatment groups, whilst QoL and self-concept improved after SMT only.

CONCLUSION

This treatment study provides further evidence that SMT and NF may reduce core symptoms, but SMT may also improve patients' self-concept and QoL and may thus in its current form be the favorable treatment option in naturalistic settings. However, several limitations of the current study implicate that further research is required before definitive conclusions and recommendations for clinical practice can be given.

CLINICAL TRIAL REGISTRATION

[www.clinicaltrials.gov], identifier [NCT01879644].

Methylphenidate for attention-deficit/hyperactivity disorder in patients with Smith-Magenis syndrome: protocol for a series of N-of-1 trials

Background

Smith–Magenis syndrome (SMS) is a rare genetic neurodevelopmental disorder characterized by intellectual disability and severe behavioural and sleep disturbances. Often, patients with SMS are diagnosed with attention-deficit/hyperactivity disorder (ADHD). However, the effectiveness of methylphenidate (MPH), the first-line pharmacological treatment for ADHD, in patients with SMS is unclear. Our objective is to examine the effectiveness of MPH for ADHD symptoms in individuals with SMS, proposing an alternative trial design as traditional randomized controlled trials are complex in these rare and heterogeneous patient populations.

Methods and analysis

We will initiate an N-of-1 series of double-blind randomized and placebo-controlled multiple crossover trials in six patients aged ≥ 6 years with a genetically confirmed SMS diagnosis and a multidisciplinary established ADHD diagnosis, according to a power analysis based on a summary measures analysis of the treatment effect. Each N-of-1 trial consists of a baseline period, dose titration phase, three cycles each including randomized intervention, placebo and washout periods, and follow-up. The intervention includes twice daily MPH (doses based on age and body weight). The primary outcome measure will be the subscale hyperactivity/inattention of the Strengths and Difficulties Questionnaire (SDQ), rated daily. Secondary outcome measures are the shortened version of the Emotion Dysregulation Inventory (EDI) reactivity index, Goal Attainment Scaling (GAS), and the personal questionnaire (PQ). Statistical analysis will include a mixed model analysis. All subjects will receive an assessment of their individual treatment effect and data will be aggregated to investigate the effectiveness of MPH for ADHD in SMS at a population level.

Conclusions

This study will provide information on the effectiveness of MPH for ADHD in SMS, incorporating personalized outcome measures. This protocol presents the first properly powered N-of-1 study in a rare genetic neurodevelopmental disorder, providing a much-needed bridge between science and practice to optimize evidence-based and personalized care.

Trial registration

This study is registered in the Netherlands Trial Register (NTR9125).

Effect of Demographic Factors on Quality of Life in Children with ADHD under Atomoxetine Treatment: 1-Year Follow-up

Attention-deficit hyperactivity disorder (ADHD) is the most common psychiatric disorder in children and adolescents. Symptoms of ADHD and its treatment can impact an individual's quality of life (QoL). The present study aimed to evaluate the effect of atomoxetine treatment, demographic characteristics, and seasonal variation on QoL in children with a recent diagnosis of ADHD and their parents. The present study included a cohort of 200 children diagnosed with ADHD. In addition to the recruited children, one of their parents was included in the study. ADHD symptoms were assessed using Conners' Parent Rating Scale. QoL of the participants was assessed with the PedsQL, while parents' QoL was evaluated using the World Health Organization Quality of Life questionnaire (WHOQOL-Bref). There was significant improvement in pediatric and parental QoL after treatment with atomoxetine. Significant factors related to better QoL in the participants included spring season, above average Conner's score, male sex, and rural residence. However, after using multivariate regression analysis, only patients' sex and Conner's score were significant predictors of pediatric QoL at the end of treatment with atomoxetine. Medical treatment significantly improved QoL in children with ADHD and their parents. Level of improvement was affected by patients' sex and ADHD severity.