Attention deficit/hyperactivity disorder and epilepsy

ADHD in Adults with Epilepsy: A Guide for Neurologists

Attention-deficit/hyperactivity disorder (ADHD) and epilepsy have one of the lesser known and yet highly debated relationships in neuropsychiatry. Similar to anxiety and depression, ADHD has a bidirectional relationship with epilepsy, in which individuals with epilepsy are more likely than the general population to have ADHD and vice versa. Most importantly, an untreated psychiatric condition can affect quality of life. Although the management of ADHD in PWE has been debated due to perceived seizure risk related to ADHD medications, a consensus has developed based on early pediatric studies that support the treatment of ADHD. However, the management of adults with ADHD, particularly in PWE, remains relatively unexplored. This critical gap in knowledge will be addressed using an illustrative case study followed by practical tips on the identification and pharmacologic management of ADHD in adults with epilepsy. The management of ADHD in PWE should begin with a thorough history, medication assessment for cognitive risk, and the addition of a brief ADHD screening tool, such as the Adult ADHD Self-Report Scale (ASRS). Treatment with stimulants, such as methylphenidate, and non-stimulants, such as atomoxetine, are effective. Caution, however, should be taken for any patients with history of bipolar disorder, as some ADHD medications may exacerbate symptoms of other psychiatric conditions. Patients can also be referred to psychotherapy, such as cognitive behavior therapy (CBT) for ADHD, in addition to or in lieu of medications, thus further minimizing potential pharmacological risk. Patients who have tried and failed multiple ADHD medications and/or who carry a more complex psychiatric history should be referred to a psychiatrist.

Attention deficit hyperactivity disorder in children with epilepsy: a multicenter cross-sectional analysis in China

BACKGROUND

The diagnosis and treatment of attention deficit hyperactivity disorder (ADHD) comorbid with epilepsy have been insufficiently addressed in China. We conducted a study in China to investigate the current status, diagnosis, and treatment of ADHD in children to further our understanding of ADHD comorbid with epilepsy, strengthen its management, and improve patients' quality of life.

METHODS

We carried out a multicenter cross-sectional survey of children with epilepsy across China between March 2022 and August 2022. We screened all patients for ADHD and compared various demographic and clinical factors between children with and without ADHD, including gender, age, age at epilepsy onset, duration of epilepsy, seizure types, seizure frequency, presence of epileptiform discharges, and treatment status. Our objective was to explore any possible associations between these characteristics and the prevalence of ADHD.

RESULTS

Overall, 395 epilepsy patients aged 6-18 years were enrolled. The age at seizure onset and duration of epilepsy ranged from 0.1-18 to 0.5-15 years, respectively. Focal onset seizures were observed in 212 (53.6%) patients, while 293 (76.3%) patients had epileptiform interictal electroencephalogram (EEG) abnormalities. Among the 370 patients treated with anti-seizure medications, 200 (54.1%) had monotherapy. Although 189 (47.8%) patients had ADHD, only 31 received treatment for it, with the inattentive subtype being the most common. ADHD was more common in children undergoing polytherapy compared to those on monotherapy. Additionally, poor seizure control and the presence of epileptiform interictal EEG abnormalities may be associated with a higher prevalence of ADHD.

CONCLUSIONS

While the prevalence of ADHD was higher in children with epilepsy than in normal children, the treatment rate was notably low. This highlights the need to give more importance to the diagnosis and treatment of ADHD in children with epilepsy.

Effective reduction in seizure severity and prevention of a fatty liver by a novel low ratio ketogenic diet composition in the rapid kindling rat model of epileptogenesis

Drug-resistant epilepsy patients may benefit from non-pharmacological therapies, such as the ketogenic diet (KD). However, its high fat content poses compliance challenges and metabolic risks. To mitigate this, we developed a novel KD composition with less fat and additional nutrients (citrate, nicotinamide riboside, and omega-3 fatty acids) for ketone-independent neuroprotection. The efficacy, metabolic and neuropathological effects of the novel KD and a classic KD were compared to a control diet in the rapid kindling model of temporal lobe epilepsy. Both KD groups entered ketosis before kindling onset, with higher ketone levels in the classic KD group. Remarkably, rats on the novel KD had slower progression of behavioral seizures as compared to rats on a control diet, while this was not the case for rats on a classic KD. Both KDs reduced electrographic after-discharge duration, preserved neurons in the dorsal hippocampus, and normalized activity in open field tests. The novel KD, despite lower fat and ketone levels, demonstrated effective reduction of behavioral seizure severity while the classic KD did not, suggesting alternative mode(s) of action are involved. Additionally, the novel KD significantly mitigated liver triglyceride and plasma fatty acid levels compared to the classic KD, indicating a reduced risk of long-term liver steatosis. Our findings highlight the potential of the novel KD to enhance therapeutic efficacy and compliance in epilepsy patients.

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.

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.

Epilepsy and psychiatric comorbidities: A bidirectional mendelian randomization study

STUDY OBJECTIVES

Psychiatric comorbidities are relatively common among patients with epilepsy; however, the underlying mechanisms of this association remain largely unknown. The objective of this Mendelian randomization (MR) study was to analyze the genetic correlations and causality underlying these reciprocal associations.

METHODS

Single-nucleotide polymorphisms associated with epilepsy (29,677 controls and 15,212 cases) and seven psychiatric comorbidities (485,436 controls and 269,495 cases) were identified from genome-wide association studies. Causal significance was estimated using inverse variance weighting. Sensitivity analyses included the weighted median, MR-Egger, and MR-PRESSO. The psychiatric comorbidities analyzed in this study included attention deficit hyperactivity disorder (ADHD), autism spectrum disorder, major depressive disorder, bipolar disorder, schizophrenia, obsessive-compulsive disorder (OCD), and anorexia nervosa.

RESULTS

Both forward and reverse genetic associations were observed for the selected psychiatric disorders. Notably, ADHD was significantly associated with an increased risk of generalized epilepsy (odds ratio [OR], 1.09; 95 % confidence interval [CI], 1.01-1.18; p = 0.013). However, MR-PRESSO detected the existence of pleiotropy (p = 0.001). Additionally, focal epilepsy was significantly associated with a higher risk of OCD (OR, 1.44; 95 % CI, 1.08-1.92; p = 0.013), and all sensitivity tests yielded favorably nonsignificant results. There was no significant genetic association between epilepsy and other examined psychiatric disorders. However, due to the detection of pleiotropy by MR-Egger and considerations related to the threshold for genetic instruments, a cautious approach is warranted in interpreting some of the results.

CONCLUSIONS

This study revealed significant genetic causality between focal epilepsy and OCD, as well as between ADHD and generalized epilepsy. However, no casual significance was observed with other psychiatric comorbidities examined. Considering the inherent limitations of MR studies, further research is warranted to definitively clarify these genetic causal associations.

Phosphatidylserine enriched with polyunsaturated n-3 fatty acid supplementation for attention-deficit hyperactivity disorder in children and adolescents with epilepsy: A randomized placebo-controlled trial

BACKGROUND

Attention-deficit hyperactivity disorder (ADHD) is a frequent comorbidity in children with epilepsy, which management mostly relies on the usual treatments of ADHD, especially methylphenidate. Supplementation with polyunsaturated n-3 Fatty Acid (PUFA) has been proposed as an alternative therapeutic approach in ADHD without epilepsy but has never been evaluated in epilepsy-associated ADHD.

METHODS

A multicenter double blind randomized placebo-controlled trial evaluating supplementation with PUFA, in eicosapentaenoic- and docosahexaenoic-acid form, conjugated to a phospholipid vector (PS-Omega3) in children aged >6 and <16-years old, and suffering from any type of epilepsy and ADHD (inattentive or combined type) according to DSM-V. After a 4-week baseline period, patients were allocated (1:1) either to placebo group or to PS-Omega 3 group and entered a 12 week-double-blind treatment period which was followed by a 12 week-open-label treatment period. The primary outcome was the reduction of the ADHD-rating scale IV attention-deficit subscore after 12 weeks of treatment.

RESULTS

The study was stopped early because of lack of eligible participants and the expected sample size was not reached. Seventy-four patients were randomized, 44 in PS-Omega3, and 30 in the placebo group. The reduction after 12 weeks of treatment in the inattention subscore of the ADHD-IV scale was -1.57 in the PS-Omega3 group, and -2.90 in the placebo group (p = 0.33, α = 5%). Results were similar after 24 weeks of treatment and for all other ADHD-related secondary outcomes, with no difference between placebo and PS-Omega3.

CONCLUSION

Our study remaining underpowered, no formal conclusion about the effect of Ps-Omega3 could be drawn. However, our data strongly suggested that the PS-Omega 3 formulation used in the current study did not improve ADHD symptoms in children with epilepsy.

PLAIN LANGUAGE SUMMARY

Supplementation with polyunsaturated n-3 Fatty Acid (PUFA) has been proposed in ADHD but has never been evaluated in patients with both epilepsy and ADHD. To address this issue, we conducted a multicenter double blind randomized placebo-controlled trial evaluating supplementation with PUFA in children with epilepsy and ADHD. The study was stopped early because of lack of eligible participants, hampering formal conclusion. However, the evolution of the ADHD symptoms at 12 and 24 weeks did not differ between placebo and PUFA supplementation, strongly suggesting that PUFA did not improve ADHD symptoms in children with epilepsy.

The ATP6V1B2 DDOD/DOORS-Associated p.Arg506* Variant Causes Hyperactivity and Seizures in Mice

The vacuolar H+-ATPase is a multisubunit enzyme which plays an essential role in the acidification and functions of lysosomes, endosomes, and synaptic vesicles. Many genes encoding subunits of V-ATPases, namely ATP6V0C, ATP6V1A, ATP6V0A1, and ATP6V1B2, have been associated with neurodevelopmental disorders and epilepsy. The autosomal dominant ATP6V1B2 p.Arg506* variant can cause both congenital deafness with onychodystrophy, autosomal dominant (DDOD) and deafness, onychodystrophy, osteodystrophy, mental retardation, and seizures syndromes (DOORS). Some but not all individuals with this truncating variant have intellectual disability and/or epilepsy, suggesting incomplete penetrance and/or variable expressivity. To further explore the impact of the p.Arg506* variant in neurodevelopment and epilepsy, we generated Atp6v1b2emR506* mutant mice and performed standardized phenotyping using the International Mouse Phenotyping Consortium (IMPC) pipeline. In addition, we assessed the EEG profile and seizure susceptibility of Atp6v1b2emR506* mice. Behavioral tests revealed that the mice present locomotor hyperactivity and show less anxiety-associated behaviors. Moreover, EEG analyses indicate that Atp6v1b2emR506* mutant mice have interictal epileptic activity and that both heterozygous (like patients) and homozygous mice have reduced seizure thresholds to pentylenetetrazol. Our results confirm that variants in ATP6V1B2 can cause seizures and that the Atp6v1b2emR506* heterozygous mouse model is a valuable tool to further explore the pathophysiology and potential treatments for vacuolar ATPases-associated epilepsy and disorders.

How have the recent updated epilepsy classifications impacted on diagnosis and treatment?

INTRODUCTION

Epilepsies are a diverse group of disorders which differ regarding prognosis for seizure control and associated comorbidities. Accurate classification is critical to choose the highest yield investigations and best therapeutic options and to provide the most accurate prognoses regarding the expected degree of seizure control, possible remission, and risk of associated comorbidities to patients and their families. This article reviews the recent updates in epilepsy classification to illustrate how accurate classification impacts care for persons with epilepsy.

AREAS COVERED

The authors discuss the ILAE 2017 Classification of the Epilepsies along with the modification of the classification for neonatal seizures and epilepsies. They also discuss the ILAE position papers on Epilepsy syndromes in neonates and infants and children of variable age and the Idiopathic Generalized Epilepsies.

EXPERT OPINION

Accurate epilepsy classification allows selection of the highest yield investigations, choice of optimal therapies, and accurate prognostication of seizures (likelihood of response to antiseizure treatments and likelihood of remission with age), as well as comorbidities (likelihood, type, and severity). As we move into the era of disease modifying therapy, early accurate identification of underlying causes with timely introduction of specific treatments will be crucial to lessen the severity of epilepsy, with improved seizure control and attenuation of associated comorbidities.

Causal effect of psychiatric disorders on epilepsy: A two-sample Mendelian randomization study

BACKGROUND

This study aims to explore the relationship between psychiatric disorders and the risk of epilepsy using Mendelian randomization (MR) analysis.

METHODS

We collected summary statistics of seven psychiatric traits from recent largest genome-wide association study (GWAS), including major depressive disorder (MDD), anxiety disorder, autism spectrum disorder (ASD), bipolar disorder (BIP), attention deficit hyperactivity disorder (ADHD), schizophrenia (SCZ), and insomnia. Then, MR analysis estimates were performed based on International League Against Epilepsy (ILAE) consortium data (n_case  = 15,212 and n_control  = 29,677), the results of which were subsequently validated in FinnGen consortium (n_case  = 6260 and n_control  = 176,107). Finally, a meta-analysis was conducted based on the ILAE and FinnGen data.

RESULTS

We found significant causal effects of MDD and ADHD on epilepsy in the meta-analysis of the ILAE and FinnGen, with corresponding odds ratios (OR) of 1.20 (95% CI 1.08-1.34, p = .001) and 1.08 (95% CI 1.01-1.16, p = .020) by the inverse-variance weighted (IVW) method respectively. MDD increases the risk of focal epilepsy while ADHD has a risk effect on generalized epilepsy. No reliable evidence regarding causal effects of other psychiatric traits on epilepsy was identified.

CONCLUSIONS

This study suggests that major depressive disorder and attention deficit hyperactivity disorder may causally increase the risk of epilepsy.

Deficit in observational learning in experimental epilepsy

Individuals use the observation of a conspecific to learn new behaviors and skills in many species. Whether observational learning is affected in epilepsy is not known. Using the pilocarpine rat model of epilepsy, we assessed learning by observation in a spatial task. The task involves a naive animal observing a demonstrator animal seeking a reward at a specific spatial location. After five observational sessions, the observer is allowed to explore the rewarded space and look for the reward. Although control observer rats succeed in finding the reward when allowed to explore the rewarded space, epileptic animals fail. However, epileptic animals are able to successfully learn the location of the reward through their own experience after several trial sessions. Thus, epileptic animals show a clear deficit in learning by observation. This result may be clinically relevant, in particular in children who strongly rely on observational learning.

Low recognition of attention deficit hyperactivity disorder in adult patients admitted to the Epilepsy Monitoring Unit

INTRODUCTION

Adult patients with epilepsy (PWE) have an 18% prevalence of comorbid attention deficit hyperactivity disorder (ADHD) compared to a prevalence of 2%-5% in the general population. Recognition of this dual diagnosis is important since stimulant therapy is both safe and effective in this population.

METHODS

Here, we aim to determine if PWE have adequate documentation for comorbid ADHD when being admitted to the Epilepsy Monitoring Unit (EMU). A retrospective review was conducted at the Baylor St. Luke's Medical Center EMU for patients presenting between July 2017 and November 2020. Patients were divided into two groups: Group I-patients without a documented ADHD diagnosis or ADHD medications and Group II-patients with a documented ADHD diagnosis and/or taking medications indicated specifically for ADHD.

RESULTS

Of 524 individual patients who presented to the EMU, only 25 patients (4.8%) had documentation of a diagnosis of ADHD and/or ADHD medications (Group II). The proportion of patients in Group II did not significantly differ based on the EMU diagnosis. However, there was a significantly greater number of other psychiatric diagnoses (p = .005) and a greater number of psychiatric medications prescribed (p < .001) in patients in Group II.

CONCLUSION

Our study suggests that ADHD is underrecognized and underdiagnosed in patients presenting to the EMU, and screening tools may be useful to help clinicians address seizure comorbidities such as ADHD.

Clinical Management of Drug Resistant Epilepsy: A Review on Current Strategies

Drug resistant epilepsy (DRE) is defined as the persistence of seizures despite at least two syndrome-adapted antiseizure drugs (ASD) used at efficacious daily dose. Despite the increasing number of available ASD, about a third of patients with epilepsy still suffer from drug resistance. Several factors are associated with the risk of evolution to DRE in patients with newly diagnosed epilepsy, including epilepsy onset in the infancy, intellectual disability, symptomatic epilepsy and abnormal neurological exam. Pharmacological management often consists in ASD polytherapy. However, because quality of life is driven by several factors in patients with DRE, including the tolerability of the treatment, ASD management should try to optimize efficacy while anticipating the risks of drug-related adverse events. All patients with DRE should be evaluated at least once in a tertiary epilepsy center, especially to discuss eligibility for non-pharmacological therapies. This is of paramount importance in patients with drug resistant focal epilepsy in whom epilepsy surgery can result in long-term seizure freedom. Vagus nerve stimulation, deep brain stimulation or cortical stimulation can also improve seizure control. Lastly, considering the effect of DRE on psychologic status and social integration, comprehensive care adaptations are always needed in order to improve patients' quality of life.