Central stimulants in the treatment of attention-deficit hyperactivity disorder (ADHD) in children and adolescents. A naturalistic study of the prescription in Sweden, 1977-2007

Impact of a Publicly-Funded Pharmacare Program on Prescription Stimulant use Among Children and Youth: A Population-Based Observational Natural Experiment

OBJECTIVE

Stimulants are first-line pharmacotherapy for individuals with attention-deficit hyperactivity disorder. However, disparities in drug coverage may contribute to inequitable treatment access. In January 2018, the government of Ontario, Canada, implemented a publicly-funded program (OHIP+) providing universal access to medications at no cost to children and youth between the ages of 0 and 24. In April 2019, the program was amended to cover only children and youth without private insurance. We studied whether these policy changes were associated with changes in prescription stimulant dispensing to Ontario children and youth.

METHODS

We conducted a population-based observational natural experiment study of stimulant dispensing to children and youth in Ontario between January 2013 and March 2020. We used interventional autoregressive integrated moving average models to estimate the association between OHIP+ and its subsequent modification with stimulant dispensing trends.

RESULTS

The implementation of OHIP+ was associated with a significant immediate increase in the monthly rate of stimulant dispensing of 53.6 individuals per 100,000 population (95% confidence interval [CI], 36.8 to 70.5 per 100,000) and a 14.2% (95% CI, 12.8% to 15.6%) relative percent increase in stimulant dispensing rates between December 2017 and March 2019 (1198.6 vs. 1368.7 per 100,000 population). The April 2019 OHIP+ program amendment was associated with an increase in monthly stimulant dispensing trends of 10.2 individuals per 100,000 population (95% CI, 5.0 to 15.5), with rates increasing 7.5% (95% CI, 6.2% to 8.7%) between March 2019 and March 2020 (1368.7 vs. 1470.8 per 100,000 population). These associations were most pronounced among males, children and youth living in the highest income neighbourhoods and individuals aged 20 to 24.

CONCLUSION

A publicly-funded pharmacare program was associated with more children and youth being dispensed stimulants.

Overdiagnosis of Attention-Deficit/Hyperactivity Disorder in Children and Adolescents: A Systematic Scoping Review

IMPORTANCE

Reported increases in attention-deficit/hyperactivity disorder (ADHD) diagnoses are accompanied by growing debate about the underlying factors. Although overdiagnosis is often suggested, no comprehensive evaluation of evidence for or against overdiagnosis has ever been undertaken and is urgently needed to enable evidence-based, patient-centered diagnosis and treatment of ADHD in contemporary health services.

OBJECTIVE

To systematically identify, appraise, and synthesize the evidence on overdiagnosis of ADHD in children and adolescents using a published 5-question framework for detecting overdiagnosis in noncancer conditions.

EVIDENCE REVIEW

This systematic scoping review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) Extension for Scoping Reviews and Joanna Briggs Methodology, including the PRISMA-ScR Checklist. MEDLINE, Embase, PsychINFO, and the Cochrane Library databases were searched for studies published in English between January 1, 1979, and August 21, 2020. Studies of children and adolescents (aged ≤18 years) with ADHD that focused on overdiagnosis plus studies that could be mapped to 1 or more framework question were included. Two researchers independently reviewed all abstracts and full-text articles, and all included studies were assessed for quality.

FINDINGS

Of the 12 267 potentially relevant studies retrieved, 334 (2.7%) were included. Of the 334 studies, 61 (18.3%) were secondary and 273 (81.7%) were primary research articles. Substantial evidence of a reservoir of ADHD was found in 104 studies, providing a potential for diagnoses to increase (question 1). Evidence that actual ADHD diagnosis had increased was found in 45 studies (question 2). Twenty-five studies showed that these additional cases may be on the milder end of the ADHD spectrum (question 3), and 83 studies showed that pharmacological treatment of ADHD was increasing (question 4). A total of 151 studies reported on outcomes of diagnosis and pharmacological treatment (question 5). However, only 5 studies evaluated the critical issue of benefits and harms among the additional, milder cases. These studies supported a hypothesis of diminishing returns in which the harms may outweigh the benefits for youths with milder symptoms.

CONCLUSIONS AND RELEVANCE

This review found evidence of ADHD overdiagnosis and overtreatment in children and adolescents. Evidence gaps remain and future research is needed, in particular research on the long-term benefits and harms of diagnosing and treating ADHD in youths with milder symptoms; therefore, practitioners should be mindful of these knowledge gaps, especially when identifying these individuals and to ensure safe and equitable practice and policy.

ADHD in children and young people: prevalence, care pathways, and service provision

Attention-deficit hyperactivity disorder (ADHD) is a common childhood behavioural disorder. Systematic reviews indicate that the community prevalence globally is between 2% and 7%, with an average of around 5%. At least a further 5% of children have substantial difficulties with overactivity, inattention, and impulsivity that are just under the threshold to meet full diagnostic criteria for ADHD. Estimates of the administrative prevalence (clinically diagnosed or recorded) vary worldwide, and have been increasing over time. However, ADHD is still relatively under-recognised and underdiagnosed in most countries, particularly in girls and older children. ADHD often persists into adulthood and is a risk factor for other mental health disorders and negative outcomes, including educational underachievement, difficulties with employment and relationships, and criminality. The timely recognition and treatment of children with ADHD-type difficulties provides an opportunity to improve long-term outcomes. This Review includes a systematic review of the community and administrative prevalence of ADHD in children and adolescents, an overview of barriers to accessing care, a description of associated costs, and a discussion of evidence-based pathways for the delivery of clinical care, including a focus on key issues for two specific age groups-younger children (aged ≤6 years) and adolescents requiring transition of care from child to adult services.

Prospective observational study protocol to investigate long-term adverse effects of methylphenidate in children and adolescents with ADHD: the Attention Deficit Hyperactivity Disorder Drugs Use Chronic Effects (ADDUCE) study

INTRODUCTION

Methylphenidate is the most frequently used medication for the treatment of attention-deficit/hyperactivity disorder (ADHD) in Europe. Following concerns about its safety, the European Commission called for research into the long-term effects of methylphenidate on children and adolescents with ADHD. The Attention Deficit Hyperactivity Disorder Drugs Use Chronic Effects (ADDUCE) research programme was designed to address this call. At the heart of this programme is a 2-year longitudinal naturalistic pharmacovigilance study being conducted in 27 European sites.

METHODS AND ANALYSIS

3 cohorts of children and adolescents (aged 6-17) living in the UK, Germany, Italy and Hungary are being recruited:Group 1 (Medicated ADHD): 800 ADHD medication-naive children and adolescents with a clinical diagnosis of ADHD about to start methylphenidate treatment for the first time.Group 2 (Unmedicated ADHD): 400 children and adolescents with a clinical diagnosis of ADHD who have never been treated with ADHD medication and have no intention of beginning medication.Group 3 (Non-ADHD): 400 children and adolescents without ADHD who are siblings of individuals in either group 1 or 2.All participants will be assessed 5 times during their 2-year follow-up period for growth and development, psychiatric, neurological and cardiovascular health. The primary outcome measure will be the height velocity SD score.

ETHICS AND DISSEMINATION

Ethical approval for the study has been granted by the East of Scotland Research Ethics Service. Following this approval, patient information leaflets and consent forms were translated as necessary and submissions made by lead sites in each of the other 3 countries to their own ethics committees. Following ethical approval in each country, local ethical permissions at each site were sought and obtained as needed. The study's website (http://www.adhd-adduce.org/page/view/2/Home) provides information for researchers, participants and the general public.

TRIAL REGISTRATION NUMBER

NCT01470261.

Non-medical prescription drug use (NMPDU) and poor quality of life in the Swedish general population

BACKGROUND AND OBJECTIVES

Quality of life has become an increasingly important measurement in the substance use field. The main aim of the present study was to examine the relationships between non-medical use of prescription analgesics and sedatives and poor quality of life in the general population.

METHODS

Data were drawn from a Swedish national household survey conducted in 2008-2009. A stratified sample of 58,000 individuals aged 15-64 was randomly selected, with a response rate of 38.3% (n = 22,095). We examined the relationships between non-medical prescription drug use and quality of life in a logistic regression analysis, controlling for other substance use and sociodemographic variables.

RESULTS

In the final logistic regression model, both non-medical use of prescription analgesics and sedatives were independently associated with poor quality of life. Non-medical use of prescription sedatives was the strongest correlate of poor quality of life among the substance use variables.

DISCUSSION AND CONCLUSIONS

The associations between non-medical prescription drug use and poor quality of life might imply a need to better identify and provide treatment for this group, especially individuals with non-medical prescription sedative use, which seems to be a particularly strong correlate of poor quality of life.

SCIENTIFIC SIGNIFICANCE

Using a large, general population sample, the present paper is one of few to examine the relationships between non-medical prescription drug use and quality of life.

Nonmedical prescription drug use (NMPDU) in the Swedish general population--correlates of analgesic and sedative use

BACKGROUND

Nonmedical prescription drug use (NMPDU) is a growing problem in many countries.

OBJECTIVES

The aim of the present study was to report correlates of and compare different subtypes of NMPDU in the Swedish general population.

METHODS

Data were drawn from a Swedish national household survey conducted in 2008-2009. A stratified sample of 58,000 individuals aged 15 to 64 was randomly selected, with a response rate of 38.3%. Hierarchical logistic regression analysis was used to compare sociodemographic, substance use, and health correlates of nonmedical analgesic use, nonmedical sedative use, and combined nonmedical use of these two types of prescription drugs.

RESULTS

In the final logistic regression model, all three patterns of NMPDU were equally associated with female gender, hazardous alcohol use, habitual smoking and cannabis use, but there were several significant differences in other demographic, health, and drug use correlates between the groups. CONCLUSIONS/IMPORTANCE: Nonmedical use of prescription analgesics, prescription sedatives and combined nonmedical use of these drugs might constitute clinically distinct subgroups of NMPDU. This study is one of few to report correlates of NMPDU from a large, national household survey in a country other than the United States.

Genetic targeting of the amphetamine and methylphenidate-sensitive dopamine transporter: on the path to an animal model of attention-deficit hyperactivity disorder

Alterations in dopamine (DA) signaling underlie the most widely held theories of molecular and circuit level perturbations that lead to risk for attention-deficit hyperactivity disorder (ADHD). The DA transporter (DAT), a presynaptic reuptake protein whose activity provides critical support for DA signaling by limiting DA action at pre- and postsynaptic receptors, has been consistently associated with ADHD through pharmacological, behavioral, brain imaging and genetic studies. Currently, the animal models of ADHD exhibit significant limitations, stemming in large part from their lack of construct validity. To remedy this situation, we have pursued the creation of a mouse model derived from a functional nonsynonymous variant in the DAT gene (SLC6A3) of ADHD probands. We trace our path from the identification of these variants to in vitro biochemical and physiological studies to the production of the DAT Val559 mouse model. We discuss our initial findings with these animals and their promise in the context of existing rodent models of ADHD.

Psychostimulants and cognition: a continuum of behavioral and cognitive activation

Psychostimulants such as cocaine have been used as performance enhancers throughout recorded history. Although psychostimulants are commonly prescribed to improve attention and cognition, a great deal of literature has described their ability to induce cognitive deficits, as well as addiction. How can a single drug class be known to produce both cognitive enhancement and impairment? Properties of the particular stimulant drug itself and individual differences between users have both been suggested to dictate the outcome of stimulant use. A more parsimonious alternative, which we endorse, is that dose is the critical determining factor in cognitive effects of stimulant drugs. Herein, we review several popular stimulants (cocaine, amphetamine, methylphenidate, modafinil, and caffeine), outlining their history of use, mechanism of action, and use and abuse today. One common graphic depiction of the cognitive effects of psychostimulants is an inverted U-shaped dose-effect curve. Moderate arousal is beneficial to cognition, whereas too much activation leads to cognitive impairment. In parallel to this schematic, we propose a continuum of psychostimulant activation that covers the transition from one drug effect to another as stimulant intake is increased. Low doses of stimulants effect increased arousal, attention, and cognitive enhancement; moderate doses can lead to feelings of euphoria and power, as well as addiction and cognitive impairment; and very high doses lead to psychosis and circulatory collapse. This continuum helps account for the seemingly disparate effects of stimulant drugs, with the same drug being associated with cognitive enhancement and impairment.

Pharmacological treatment and demographic characteristics of pediatric patients with Attention Deficit Hyperactivity Disorder, Sweden

The aim of this study was to describe the pediatric population with ADHD and their pharmacological treatment. Using the Swedish National Patient Register and the Prescribed Drug Register we identified individuals below 19 years of age who were diagnosed or medically treated for ADHD for the first time 2006-2007. The unique patient identifiers were used to link information from the two registers to describe demographic characteristics, hospital care and drug treatments. Logistic regression model estimated the association between age, sex, frequency of hospitalization, diagnosis or treatment for other mental disorders and risk of gap in the treatment. Totally the study included 7931 patients of whom 74% were males. The mean age at first diagnosis was 12 years. Some 84% were medically treated for ADHD and approximately 90% received methylphenidate as the first substance. Combination therapy was rare and the most common combination was methylphenidate and atomoxetine. More than 55% of the patients, which could be followed up for two years after start of treatment, had at least one treatment gap of six months. Older age at diagnosis, lower number of hospitalizations and comorbidity with other mental disorders increased risks of gaps in medication. Approximately one fifth of the patients recorded in the National Patient Register as diagnosed with ADHD did not receive pharmacological treatment. Medication adherence seems to be low, when measured as gaps in treatment.

The diversion and misuse of pharmaceutical stimulants: what do we know and why should we care?

AIMS

To examine the literature pertaining to the diversion and misuse of pharmaceutical stimulants.

METHODS

Relevant literature was identified through comprehensive MEDLINE, EMBASE and PubMed searches.

RESULTS

The evidence to date suggests that the prevalence of diversion and misuse of pharmaceutical stimulants varies across adolescent and young adult student populations, but is higher than that among the general population, with the highest prevalence found among adults with attention deficit-hyperactive disorder (ADHD) and users of other illicit drugs. Concerns that these practices have become more prevalent as a result of increased prescribing are not supported by large-scale population surveys. Information on trends in misuse in countries where there have been recent increases in prescription and consumption rates, however, is limited. Little is known about the frequency and chronicity of misuse, or the extent of associated harms, particularly among those populations, i.e. adolescents, young adult student populations, those with ADHD and illicit drug users, where abuse may be more likely to occur.

CONCLUSIONS

Continued monitoring of the diversion and misuse of pharmaceutical stimulants is of major clinical importance. Despite recognition of the abuse liability of these medications, there is a paucity of data on the prevalence, patterns and harms of diversion and misuse among populations where problematic use and abuse may be most likely to occur (e.g. adolescents, young adults, illicit drug users). Comprehensive investigations of diversion and misuse among these populations should be a major research priority, as should the assessment of abuse and dependence criteria among those identified as regular users.

Maternal and paternal psychopathology increases risk of offspring ADHD equally

BACKGROUND

Parental psychopathology may increase the risk of attention-deficit hyperactivity disorder (ADHD) in the offspring. The aim of this study was to analyze if/how gender influences the association between parental psychiatric/addictive disorders and ADHD medication in the offspring.

METHODS

Register study in national birth cohorts of 1.1 million 6-19-year-olds. In this population, 7960 individuals with ADHD medication were identified in the Swedish Prescribed Drug Register during 2006. Data on parental psychiatric/addictive disorders and suicide death were obtained through linkages to national registers. Logistic regression was used for analyses with multiple adjustments for socio-economic, regional and demographic confounders.

RESULTS

Parental diagnosis related to illicit drugs was associated with the highest odds ratios (ORs) of ADHD medication (OR: -3.5-4), followed by suicide attempt/death (OR: -3-3.5), alcohol (OR: -2.5-3), affective disorder (OR: -2.5) and psychosis (OR: -2-2.5). The ORs were of similar magnitudes for maternal and paternal psychopathology and did not vary by the gender of the offspring. Adjusting for social characteristics decreased the ORs substantially and in the same way regarding fathers' and mothers' possible influence on the risk of ADHD in children.

CONCLUSIONS

Neither parental nor offspring gender seems to influence the link between parental addictive/psychiatric disorder and offspring ADHD.