Attention-deficit/hyperactivity disorder medication and seizures

Children with ADHD and EEG abnormalities at baseline assessment, risk of epileptic seizures and maintenance on methylphenidate three years later

PURPOSE

This study aimed to assess the incidence of EEG abnormalities (EEG-ab) in children diagnosed with ADHD, investigate the risk of epileptic seizures (SZ) and maintenance on methylphenidate (MPH) over a three-year period.

METHODS

A total of 517 ADHD children aged 6-14 years were included. Baseline assessments included the identification of EEG-ab, ADHD inattentive subtype (ADHD-I), comorbid epilepsy, the use of antiepileptic drugs (AEDs) and the use of MPH. At the 3-year follow-up, assessments included the presence of EEG-ab, maintenance on MPH, AED usage, SZ risk in cases with EEG-epileptiform abnormalities (EEG-epi-ab), compared with control ADHD cases without EEG-epi-ab matched for age and gender.

RESULTS

EEG-ab were identified in 273 (52.8%) cases. No statistically significant differences were observed between the EEG-ab and EEG-non-ab groups in terms of age, gender, ADHD-I type or initial use of MPH. EEG non-epileptiform abnormalities (EEG-non-epi-ab) were found in 234 out of 478 (49%) cases without EEG-epi-ab. Notably, EEG-non-epi-ab occurred more frequently in the group of 39 cases with EEG-epi-ab (30/39 (76.9%) vs. 9/39, (21.3%), a subset selected for 3-year follow-up. At 3-year-follow-up no statistically significant difference was found in maintenance on MPH in ADHD cases with and without EEG-epi-ab. Nobody of ADHD cases without comorbid epilepsy or with comorbid epilepsy with achieved SZ freedom developed new SZ. Only 3 children with drug resistant epilepsy experienced SZs, without increase in SZ frequency. The disappearance rate of EEG-epi-ab was higher than that EEG-non-epi-ab (71.8% vs. 33.3%).

CONCLUSIONS

Children with and without EEG-ab exhibited similar patterns of MPH use (initial use, positive response, and maintenance on MPH). The presence of comorbid epilepsy and EEG-ab, with or without EEG-epi-ab, was not associated with an increased risk of SZ despite the use of MPH.

Advances in the etiology and neuroimaging of children with attention deficit hyperactivity disorder

Attention deficit hyperactivity disorder (ADHD) is the most common neurodevelopmental disorder in children, characterized by age-inappropriate inattention, hyperactivity, and impulsivity, which can cause extensive damage to children's academic, occupational, and social skills. This review will present current advancements in the field of attention deficit hyperactivity disorder, including genetics, environmental factors, epigenetics, and neuroimaging features. Simultaneously, we will discuss the highlights of promising directions for further study.

Do psychotropic drugs cause seizures?

Patients with epilepsy often present with concurrent psychiatric disorders, posing unique challenges for healthcare providers. This review explores the intricate relationship between psychiatric comorbidities, epilepsy, and psychotropic medications to inform clinical decision-making. The bidirectional association between epilepsy and psychiatric conditions complicates treatment, with psychiatric symptoms preceding or following seizure onset. The review discusses the seizure risks associated with antidepressants, CNS stimulants, and antipsychotics, shedding light on both historical perspectives and recent empirical evidence. Antidepressants, particularly tricyclic antidepressants (TCAs), are known to pose seizure risks, while newer agents like selective serotonin reuptake inhibitors (SSRIs) exhibit lower incidences and even potential anticonvulsant effects. Contrary to common beliefs, CNS stimulants used in attention-deficit/hyperactivity disorder (ADHD) treatment show efficacy without significantly increasing seizure risk. However, the association between ADHD and seizures warrants careful consideration. Among antipsychotics, clozapine stands out for its heightened seizure risks, especially during titration and at high doses, necessitating close monitoring and individualized approaches. Understanding the nuanced seizure risks associated with different psychotropic medications is crucial for optimizing patient care and minimizing iatrogenic seizures in this vulnerable population. By recognizing the complexities of psychiatric comorbidities in epilepsy and considering the unique challenges they pose, healthcare providers can make informed decisions to enhance patient safety and treatment outcomes. This review offers practical insights to guide clinicians in navigating the intricate landscape of managing psychiatric comorbidities in patients with epilepsy.

Comorbidity of attention deficit hyperactivity disorder in a patient with epilepsy: Staring down the challenge of inattention versus nonconvulsive seizures

Epilepsy is a heterogeneous disorder of recurrent seizures which often is comorbid with anxiety, depression, attention deficit hyperactivity disorder (ADHD), intellectual disability (ID), and other psychiatric manifestations. Treating both epilepsy and behavioral symptoms from psychiatric disorders can result in polypharmacy with interactions of medications leading to both worsened efficacy of antiseizure medications due to psychotropic effects and worsening of psychiatric symptoms due to antiseizure medication side effects. We aim to suggest pragmatic strategies for the neurologist in the diagnosis and management of comorbid ADHD in patients with epilepsy based on the International League Against Epilepsy (ILAE) Pediatric Commission guidelines and additional literature review. The screening tool of choice for the symptoms of ADHD is validated in the country of practice and written in the language of the family, though various screening tools and advantages and disadvantages of each will be discussed. Once ADHD is diagnosed, recent safety data suggest that Methylphenidate, Amphetamine, and Atomoxetine are generally safe for patients with epilepsy. We present a case of a child with epilepsy and ADHD and discuss the clinical signs, symptoms, and strategies for treatment as well as when to refer to child psychiatry.

The association between early childhood onset epilepsy and attention-deficit hyperactivity disorder (ADHD) in 3237 children and adolescents with Autism Spectrum Disorder (ASD): a historical longitudinal cohort data linkage study

Children and young people with Autism Spectrum Disorder (ASD) have an increased risk of comorbidities, such as epilepsy and Attention-Deficit/Hyperactivity Disorder (ADHD). However, little is known about the relationship between early childhood epilepsy (below age 7) and later ADHD diagnosis (at age 7 or above) in ASD. In this historical cohort study, we examined this relationship using an innovative data source, which included linked data from routinely collected acute hospital paediatric records and childhood community and inpatient psychiatric records. In a large sample of children and young people with ASD (N = 3237), we conducted a longitudinal analysis to examine early childhood epilepsy as a risk factor for ADHD diagnosis while adjusting for potential confounders, including socio-demographic characteristics, intellectual disability, family history of epilepsy and associated physical conditions. We found that ASD children and young people diagnosed with early childhood epilepsy had nearly a twofold increase in risk of developing ADHD later in life, an association which persisted after adjusting for potential confounders (adjusted OR = 1.72, CI95% = 1.13-2.62). This study suggests that sensitive monitoring of ADHD symptoms in children with ASD who have a history of childhood epilepsy may be important to promote early detection and treatment. It also highlights how linked electronic health records can be used to examine potential risk factors over time for multimorbidity in neurodevelopmental conditions.

An updated safety review of the current drugs for managing ADHD in children

INTRODUCTION

Attention-Deficit/Hyperactivity Disorder (ADHD) is a highly prevalent condition that causes persistent problems with attention and/or hyperactivity-impulsivity and often results in significant impairment when left untreated. Medications for this disorder continue to evolve and provide new treatment options. Ongoing review of related medication safety and tolerability remains an important task for prescribers.

AREAS COVERED

This manuscript provides an updated safety review of medications used to treat ADHD in children and adolescents. PubMed and OneSearch online databases were utilized to search for literature relevant to the topic of ADHD medications and safety. Clinical trials of medications used to treat ADHD, systematic reviews and meta-analyses, and articles covering specific safety issues (adverse or unfavorable events) such as cardiovascular effects, seizures, impact on growth, depression, suicidal ideation, substance use disorders, psychosis, and tics are described.

EXPERT OPINION

Available pharmacologic treatments for ADHD have favorable efficacy, safety and tolerability and allow many patients to achieve significant improvement of their symptoms. Despite the availability of multiple stimulant and non-stimulant formulations, some individuals with ADHD may not tolerate available medications or attain satisfactory improvement. To satisfy unmet clinical needs, ADHD pharmaceutical research with stimulant and nonstimulant formulations targeting dopamine, norepinephrine, and novel receptors is ongoing.

Epilepsy and attention-deficit/hyperactivity disorder in children and adolescents: An overview of etiology, prevalence, and treatment

Epilepsy and attention-deficit/hyperactivity disorder (ADHD) are closely connected and commonly seen in both children and adults. Each of the disorders has major psychosocial and quality of life (QOL) effects, and their co-occurrence makes coping even more challenging for both the patients and their families. Moreover, an adverse effect of some anti-seizure medications can potentially induce or exacerbate symptoms of ADHD on the one hand, while some ADHD medications may increase seizure risk on the other. The combination of proper diagnosis and appropriate treatment may improve or even prevent many of the complications associated with these conditions. The objectives of this review are to present the complex relationship between epilepsy and ADHD, looking into the pathophysiological, anatomical, and functional perspectives along with the psychosocial and QOL influences and the recommended treatment approaches in accordance with the latest literature.

Epilepsy and Attention Deficit Hyperactivity Disorder: Connection, Chance, and Challenges

Comorbidities are common in children with epilepsy, with nearly half of the patients having at least one comorbidity. Attention deficit hyperactivity disorder (ADHD) is a psychiatric disorder characterized by hyperactivity and inattentiveness level disproportional to the child’s developmental stage. The burden of ADHD in children with epilepsy is high and can adversely affect the patients’ clinical outcomes, psychosocial aspects, and quality of life. Several hypotheses were proposed to explain the high burden of ADHD in childhood epilepsy; the well-established bidirectional connection and shared genetic/non-genetic factors between epilepsy and comorbid ADHD largely rule out the possibility of a chance in this association. Stimulants are effective in children with comorbid ADHD, and the current body of evidence supports their safety within the approved dose. Nonetheless, safety data should be further studied in randomized, double-blinded, placebo-controlled trials. Comorbid ADHD is still under-recognized in clinical practice. Early identification and management of comorbid ADHD are crucial to optimize the prognosis and reduce the risk of adverse long-term neurodevelopmental outcomes. The identification of the shared genetic background of epilepsy and ADHD can open the gate for tailoring treatment options for these patients through precision medicine.

Mainstreaming adult ADHD into primary care in the UK: guidance, practice, and best practice recommendations

BACKGROUND

ADHD in adults is a common and debilitating neurodevelopmental mental health condition. Yet, diagnosis, clinical management and monitoring are frequently constrained by scarce resources, low capacity in specialist services and limited awareness or training in both primary and secondary care. As a result, many people with ADHD experience serious barriers in accessing the care they need.

METHODS

Professionals across primary, secondary, and tertiary care met to discuss adult ADHD clinical care in the United Kingdom. Discussions identified constraints in service provision, and service delivery models with potential to improve healthcare access and delivery. The group aimed to provide a roadmap for improving access to ADHD treatment, identifying avenues for improving provision under current constraints, and innovating provision in the longer-term. National Institute for Health and Care Excellence (NICE) guidelines were used as a benchmark in discussions.

RESULTS

The group identified three interrelated constraints. First, inconsistent interpretation of what constitutes a 'specialist' in the context of delivering ADHD care. Second, restriction of service delivery to limited capacity secondary or tertiary care services. Third, financial limitations or conflicts which reduce capacity and render transfer of care between healthcare sectors difficult. The group recommended the development of ADHD specialism within primary care, along with the transfer of routine and straightforward treatment monitoring to primary care services. Longer term, ADHD care pathways should be brought into line with those for other common mental health disorders, including treatment initiation by appropriately qualified clinicians in primary care, and referral to secondary mental health or tertiary services for more complex cases. Long-term plans in the NHS for more joined up and flexible provision, using a primary care network approach, could invest in developing shared ADHD specialist resources.

CONCLUSIONS

The relegation of adult ADHD diagnosis, treatment and monitoring to specialist tertiary and secondary services is at odds with its high prevalence and chronic course. To enable the cost-effective and at-scale access to ADHD treatment that is needed, general adult mental health and primary care must be empowered to play a key role in the delivery of quality services for adults with ADHD.

Protective Effect of Escitalopram on Hepatocellular Carcinoma by Inducing Autophagy

Background: Hepatocellular carcinoma (HCC) is an aggressive cancer with poor prognosis. Although recent research has indicated that selective serotonin reuptake inhibitors (SSRIs), including escitalopram, have anticancer effects, little is known about the effects of escitalopram on HCC. Methods: Both in vitro and in vivo studies were conducted to verify the potentials of escitalopram on HCC treatment. To explore whether the effects of escitalopram are clinically consistent with laboratory findings, a nationwide population-based cohort study was also adopted to examine the association between escitalopram and HCC risk. Results: As compared with THLE-3 cells, escitalopram significantly inhibited the proliferation of HepG2 and Huh-7 cells. Specifically, escitalopram significantly induced autophagy in HepG2 and Huh-7 cells by increasing the LC3-II/LC3-I ratio and the expression of ATG-3, ATG-5, ATG-7, and Beclin-1 proteins. Moreover, escitalopram significantly inhibited the growth of xenografted Huh-7 cells in SCID mice that were treated with 12.5 mg/kg escitalopram. Accordingly, the risk of HCC was negatively correlated with escitalopram use. Conclusions: These findings provided evidence supporting the therapeutic potential of escitalopram for HCC. Both laboratory and nationwide population-based cohort evidence demonstrated the attenuated effects of escitalopram on HCC.

Non-mental diseases associated with ADHD across the lifespan: Fidgety Philipp and Pippi Longstocking at risk of multimorbidity?

Several non-mental diseases seem to be associated with an increased risk of ADHD and ADHD seems to be associated with increased risk for non-mental diseases. The underlying trajectories leading to such brain-body co-occurrences are often unclear - are there direct causal relationships from one disorder to the other, or does the sharing of genetic and/or environmental risk factors lead to their occurring together more frequently or both? Our goal with this narrative review was to provide a conceptual synthesis of the associations between ADHD and non-mental disease across the lifespan. We discuss potential shared pathologic mechanisms, genetic background and treatments in co-occurring diseases. For those co-occurrences for which published studies with sufficient sample sizes exist, meta-analyses have been published by others and we discuss those in detail. We conclude that non-mental diseases are common in ADHD and vice versa and add to the disease burden of the patient across the lifespan. Insufficient attention to such co-occurring conditions may result in missed diagnoses and suboptimal treatment in the affected individuals.

Do Psychotropic Drugs Cause Epileptic Seizures? A Review of the Available Evidence

Psychiatric comorbidities in patients with epilepsy are common. A bidirectional relationship has been well described where not only patients with epilepsy have a higher prevalence of psychiatric comorbidities but also patients with primary psychiatric disorders are at an increased risk of developing seizures. The aim of this review is to highlight the complex relationship between epilepsy and common psychiatric disorders and to answer the question whether psychotropic medications are proconvulsant by reviewing the preclinical and clinical literature. The evidence shows that the majority of psychotropic medications are not proconvulsant when used in therapeutic doses with the exception of a subset of medications, mainly bupropion IR and certain antipsychotic drugs such as clozapine. An effective treatment of psychiatric comorbidities in patients with epilepsy must consider not only the potential therapeutic effect of the drug, but also its potential iatrogenic effects on the seizure disorder.

Attention deficit/hyperactivity disorder and epilepsy

PURPOSE OF REVIEW

Attention deficit/hyperactivity disorder (ADHD) is a frequent comorbidity in patients with epilepsy and is associated with important psychosocial and academic consequences. Evidence are now available to guide diagnosis and treatment of patients with both ADHD and epilepsy.

RECENT FINDINGS

The prevalence of ADHD varies from 12 to 39% in patients with newly diagnosed epilepsy to 70% in drug-resistant epilepsy. The diagnosis of ADHD requires parent-validated and teacher-validated rating scales, based on the Diagnostic and Statistical Manual of Mental Disorders (DSM)-IV and DSM-V, to confirm the information in the rating scales by interviewing parents and to exclude other causes of symptoms. Treatment with methylphenidate is associated with clinically significant improvement of ADHD symptoms in 60-75% of patients. Recent data reinforce the hypothesis that ADHD medications do not increase risk of seizures, even in patients with epilepsy. Beyond pharmacological management, experts have recommended to include multidisciplinary involvement in transition clinics for patients with both comorbid ADHD and epilepsy.

SUMMARY

Management of ADHD in patients with epilepsy requires implementation of evidence-based data in clinical practice both for diagnosis and treatment. Currently, there is no specific treatment of ADHD associated with epilepsy and its treatment is based on the usual treatments of ADHD, with reassuring data about their safety in epilepsy.

Drug Treatment of Epilepsy Neuropsychiatric Comorbidities in Children

There is increasing recognition that epilepsy can be associated with a broad spectrum of comorbidities. While epileptic seizures are an essential element of epilepsy in children, there is a spectrum of neurological, mental health and cognitive disorders that add to the disease burden of childhood epilepsy resulting in a decreased quality of life. The most common comorbid conditions in childhood epilepsy include depression, anxiety, autism spectrum disorders, sleep disorders, attention deficits, cognitive impairment, and migraine. While epilepsy can result in comorbidities, many of the comorbidities of childhood have a bi-directional association, with the comorbid condition increasing risk for epilepsy and epilepsy increasing the risk for the comorbid condition. The bidirectional feature of epilepsy and the comorbidities suggest a common underlying pathological basis for both the seizures and comorbid condition. While recognition of the comorbid conditions of pediatric epilepsies is increasing, there has been a lag in the development of effective therapies partly out of concern that drugs used to treat the comorbid conditions could increase seizure susceptibility. There is now some evidence that most drugs used for comorbid conditions are safe and do not lower seizure threshold. Unfortunately, the evidence showing drugs are effective in treating many of the childhood comorbidities of epilepsy is quite limited. There is a great need for randomized, placebo-controlled drug trials for efficacy and safety in the treatment of comorbidities of childhood epilepsy.

Methylphenidate for attention problems in epilepsy patients: Safety and efficacy

Children with attention deficit hyperactivity disorder (ADHD) have an increased risk of seizures, and children with epilepsy have an increased prevalence of ADHD. Adults with epilepsy often have varying degrees of attentional dysfunction due to multiple factors, including anti-seizure medications, frequent seizures, interictal discharges, underlying lesions, and psychiatric comorbidities. Currently, there are no approved medications for the treatment of epilepsy-related attentional dysfunction. Methylphenidate (MPH) is a stimulant, FDA-approved for the treatment of ADHD, and often used for ADHD in the setting of pediatric epilepsy. Large database and registry studies indicate safety of MPH in children with ADHD and epilepsy, with no significant effect on seizure frequency. Small single-dose and open-label studies suggest efficacy of MPH in adults with epilepsy-related attention deficits. Methylphenidate represents a possible treatment for attentional dysfunction due to epilepsy, but large, randomized, placebo-controlled, double-blinded studies are needed.

Psychiatric Comorbidities in Pediatric Epilepsy

PURPOSE OF REVIEW

Psychiatric comorbidities are close to 5-times higher in children and youth with epilepsy (CYE) compared to general population. With epilepsy being one of the most common neurological disorders in children, we provide a timely review of psychiatric issues in CYE.

RECENT FINDINGS

A meta-analysis found a pooled prevalence of anxiety in 18.9% and depression in 13.5% of CYE. Attention deficit hyperactivity disorder (ADHD) is 2.5 to 5.5 times higher in CYE compared to healthy counterparts. Recent evidence highlights that behavioral adverse effects may lead to discontinuation of anti-epileptic drugs (AEDs) in more than 10% of CYE. Up to 70% CYE shows elevation in baseline psychological symptoms after AED initiation. Identifying psychiatric symptoms can be easily accomplished by the routine use of psychiatric screening instruments in CYE clinics, which is associated with improved health-related quality of life (HRQOL). Psychoeducation is a key component for any visit with CYE. There is some evidence of the effectiveness of behavioral psychological interventions for CYE. There are no therapeutic trials of psychotropics in CYE, but treatment recommendations based on the experience in adults with epilepsy and general population are applicable. Early diagnosis and management of psychiatric comorbidities leads to improvement in HRQOL of CYE. This requires routine screening and a multidisciplinary teamwork.

Depression and Suicidal Behavior in Young Adult Men and Women With ADHD: Evidence From Claims Data

OBJECTIVE

This study used commercial claims data to examine the effects of ADHD and sex on the prevalence of depression, suicidal ideation, and suicide attempts in a sample of young adult men and women (aged 18-25 years) with and without attention-deficit/hyperactivity disorder (ADHD). Patterns of treatment use for these conditions was also explored.

METHODS

Young adults with ADHD (162,263 women and 225,705 men) having at least 2 claims with the International Classification of Diseases, Ninth Revision (ICD-9), code for ADHD and a sex- and age-matched group of young adults without an ICD-9 code for ADHD (162,263 women and 225,705 men) were identified. The prevalence of ICD-9 depression and suicidal behavior along with the use and cost of related treatment were compared between young adults with and without ADHD using 2014 claims data.

RESULTS

Compared to young adults without ADHD, young adults with ADHD were more frequently identified with depression, suicidal ideation, and suicide attempts. Depression and suicidal ideation were identified more frequently among women with ADHD compared to all other groups. Young adults with ADHD were more frequently engaged in outpatient and inpatient mental health care compared to young adults without ADHD (P < .0001 in each instance). Furthermore, overall costs of outpatient and inpatient care were greater among young adults with ADHD compared to young adults without ADHD (P < .0001 in each instance).

CONCLUSIONS

These findings highlight the substantial burden of depression and suicidal behavior among young adults with ADHD, particularly women, and underlie the need for more research focused on mitigating risk for depression and suicidal behavior among both men and women with ADHD.

Etomidate Induced Seizure: Adverse Drug Event Case Report

OBJECTIVE/PURPOSE

To report a case of etomidate induced seizure in a patient that received 0.15 mg/kg of etomidate for a procedural sedation which resolved without intervention.

SUMMARY

A 68-year-old woman presented to the emergency department with a dislocated shoulder. Etomidate was given to the patient for procedural sedation to allow the physician to reduce the shoulder dislocation. Upon administration of the medication, the patient began seizing; this lasted for about 2 minutes. No medications were needed for cessation of the seizure.

CONCLUSION

A causality assessment determined that the adverse effect of the epileptogenic action in etomidate was possible. Limited data is available in regard to the incidence rate of this adverse effect.

Association between methylphenidate treatment and risk of seizure: a population-based, self-controlled case-series study

BACKGROUND

Individuals with attention-deficit hyperactivity disorder (ADHD) are at increased risk of seizures. Stimulant medications such as methylphenidate are the most commonly prescribed treatment for ADHD, but the association between their therapeutic use and the risk of seizures is unclear. We aimed to investigate the association between methylphenidate treatment and the risk of seizure.

METHODS

For this population-based observational study, we used the electronic medical record database of the Hong Kong Clinical Data Analysis And Reporting System to identify individuals aged 6-25 years who received at least one methylphenidate prescription during the study period. Individuals with records of seizure or epilepsy before the study period were excluded. Individuals treated with methylphenidate who had seizures during the study period were included in the subsequent analyses, and a self-controlled case-series design was used to control for time-invariant individual characteristics. We did additional analyses using skin infection as a negative control outcome. We compared relative incidence of seizure during periods when individuals were exposed to methylphenidate with that during non-exposed periods.

FINDINGS

Of 29 604 individuals prescribed methylphenidate between Jan 1, 2001, and Dec 31, 2017, 269 (199 males and 70 females) had incident seizures. The mean age at baseline was 6·66 years (SD 2·01) and the median age at the incident seizure was 9·69 years (IQR 7·62-12·99). The overall incidence of seizure during methylphenidate treatment was 4·4 per 10 000 patient-years. We detected an increased risk of seizure during the first 30 days of methylphenidate treatment compared with that during non-exposed periods, with an incidence rate ratio of 4·01 (95% CI 2·09-7·68). No increase in risk was identified during the following 31-180 days of treatment (1·13, 0·56-2·25) or during subsequent treatment (1·38, 0·92-2·07). We did not identify an increased risk in any risk window for the negative control outcome analysis. No individuals died because of a seizure during the study period.

INTERPRETATION

The incidence of seizures was higher in the period immediately after the start of methylphenidate treatment than in the non-exposed period. No increased risk was observed during continuation of methylphenidate treatment. The association between methylphenidate treatment and seizures immediately after initiation of medication can be seen as a potential safety signal. Monitoring of neurological outcomes in individuals with ADHD is recommended when they first start methylphenidate treatment.

FUNDING

Hong Kong Research Grants Council.

Should pediatric neurologists play a role in the management of the most common psychiatric comorbidities in children with epilepsy? Practical considerations

Child neurologists should provide initial care for the mental health problems of children and adolescents with epilepsy. Attention deficit hyperactivity disorder (ADHD), autism spectrum disorders are common comorbidities of childhood epilepsy. The psychotropic drugs used to treat mental health disorders can be safely employed in children with seizures. Child neurologists can diagnose common behavioral problems, should be comfortable with first-line agents to treat common psychiatric illnesses, and should recognize when support from psychologists or child and adolescent psychiatrists is needed. This article is part of the Special Issue "Obstacles of Treatment of Psychiatric Comorbidities in Epilepsy".

Risks and Benefits of Attention-Deficit/Hyperactivity Disorder Medication on Behavioral and Neuropsychiatric Outcomes: A Qualitative Review of Pharmacoepidemiology Studies Using Linked Prescription Databases

Attention-deficit/hyperactivity disorder (ADHD) medication is one of the most commonly prescribed medication classes in child and adolescent psychiatry, and its use is increasing rapidly in adult psychiatry. However, major questions and concerns remain regarding the benefits and risks of ADHD medication, especially in real-world settings. We conducted a qualitative systematic review of studies that investigated the effects of ADHD medication on behavioral and neuropsychiatric outcomes using linked prescription databases from the last 10 years and identified 40 studies from Europe, North America, and Asia. Among them, 18 used within-individual designs to account for confounding by indication. These studies suggested short-term beneficial effects of ADHD medication on several behavioral or neuropsychiatric outcomes (i.e., injuries, motor vehicle accidents, education, substance use disorder), with estimates suggesting relative risk reduction of 9% to 58% for these outcomes. The within-individual studies found no evidence of increased risks for suicidality and seizures. Replication studies are needed for several other important outcomes (i.e., criminality, depression, mania, psychosis). The available evidence from pharmacoepidemiology studies on long-term effects of ADHD medication was less clear. We discuss time-varying confounding and other limitations that should be considered when interpreting results from pharmacoepidemiology studies. Furthermore, we highlight several knowledge gaps to be addressed in future research and implications for research on mechanisms of outcomes of ADHD medications.

Medication treatment for attention-deficit/hyperactivity disorder and the risk of acute seizures in individuals with epilepsy

OBJECTIVE

Attention-deficit/hyperactivity disorder (ADHD) affects 10%-30% of individuals with epilepsy, yet concerns remain regarding the safety of ADHD medication in this group. The objective of this study was to examine the risk of acute seizures associated with ADHD medication in individuals with epilepsy.

METHODS

A total of 21 557 individuals with a seizure history born between 1987 and 2003 were identified from Swedish population registers. Within this study population, we also identified 6773 youth (<19 years of age) who meet criteria for epilepsy, and 1605 youth with continuous antiepileptic drug (AED) treatment. ADHD medication initiation and repeated medication periods were identified from the Swedish Prescribed Drug Register between January 1, 2006 and December 31, 2013. Acute seizures were identified via unplanned visits to hospital or specialist care with a primary seizure discharge diagnosis in the Swedish National Patient Register during the same period. Conditional Poisson regression was used to compare the seizure rate during the 24 weeks before and after initiation of ADHD medication with the rate during the same 48 weeks in the previous year. Cox regression was used to compare the seizure rate during ADHD medication periods with the rate during nonmedication periods. Comparisons were made within-individual to adjust for unmeasured, time?constant confounding.

RESULTS

Among 995 individuals who initiated ADHD medication during follow-up, within-individual analyses showed no statistically significant difference in the rate of seizures during the 24 weeks before and after medication initiation, compared to the same period in the previous year. In the full study population 11 754 seizure events occurred during 136 846 person-years and 1855 individuals had at least one ADHD medication period. ADHD medication periods were associated with a reduced rate of acute seizures (hazard ratio [HR] 0.73, 95% confidence interval [CI] 0.57-0.94), compared to nonmedication periods within the same individual. Similar associations were found in youth with epilepsy and continuous AED treatment, when adjusting for AEDs, and across sex, age, and comorbid neurodevelopmental disorders.

SIGNIFICANCE

We found no evidence for an overall increased rate of acute seizures associated with ADHD medication treatment among individuals with epilepsy. These results suggest that epilepsy should not automatically preclude patients from receiving ADHD medications.

[Research advances in pathogenesis of attention deficit hyperactivity disorder]

Both of genetic and environmental factors play important roles in the pathogenesis of attention deficit hyperactivity disorder (ADHD), and genetic factors can increase the susceptibility of individuals to environmental risk factors. There are extensive and various structural and functional abnormalities of the brain in patients with ADHD. Given the close functional relationship between brain areas, exploration has also been expanded to the dysfunction of brain network in recent years. As for the biochemical mechanism underlying ADHD, monoamine neurotransmitters are still most valued, and abnormalities of brain-derived neurotrophic factors and glutamic acid/γ-aminobutyric acid imbalance may also be present. Due to the abnormal neuroendocrine function and connectivity between brain areas caused by the synergistic effect of genetic and environmental factors, the prefrontal cortex loses control of the lower brain areas, so that the basal ganglia and amygdala affect normal behavioral and emotional reactions. Dysfunction of the endocrine axes may further aggravate neuroendocrine disorder. The above process may eventually lead to changes in brain structure and function, which may be associated with the development of ADHD. However, considering the heterogeneity of ADHD, its pathological process may not be the same, and the exact mechanism needs to be further clarified.