A working group of the International League Against Epilepsy (ILAE), consisting of twenty experts spanning the globe (U.S., U.K., France, Germany, Japan, India, South Africa, Kenya, Brazil), recently published a “consensus paper” summarizing and evaluating what is currently known about comorbid epilepsy with ADHD, and best practices.

ADHD is two to five times more prevalent among children with epilepsy. The authors suggest that ADHD is underdiagnosed in children with epilepsy because its symptoms are often attributed either to epilepsy itself, or to the effects of antiepileptic drugs (AEDs).

The working group did a systematic search of the English-language research literature. It then reached consensus on practice recommendations, graded on the strength of the evidence.

Three recommendations were graded A, indicating they are well-established by evidence:

• Children with epilepsy with comorbid intellectual and developmental disabilities are at increased risk of ADHD.
• There is no increased risk of ADHD in boys with epilepsy compared to girls with epilepsy.
• The anticonvulsant valproate can exacerbate attentional issues in children with childhood absence epilepsy (absence seizures look like staring spells during which the child is not aware or responsive). Moreover, a single high-quality population-based study indicates that valproate use during pregnancy is associated with inattentiveness and hyperactivity in offspring.

Four more were graded B, meaning they are probably useful/predictive:

• Poor seizure control is associated with increased risk of ADHD.
• Data support the ability of the Strengths and Difficulties Questionnaire (SDQ) to predict ADHD diagnosis in children with epilepsy: “Borderline or abnormal SDQ total scores are highly correlated with the presence of a validated psychiatric diagnosis (93.6%), of which ADHD is the most common (31.7%).” The SDQ can therefore be useful as a screening tool.
• Evidence supports the efficacy of methylphenidate in children with epilepsy and comorbid ADHD.
• Methylphenidate is tolerated in children with epilepsy.

At the C level of being possibly useful, there is limited evidence that supports that atomoxetine is tolerated in children with ADHD and epilepsy, and that the combined use of drugs for ADHD and epilepsy (polytherapy) is more likely to be associated with behavioral problems than monotherapy. In the latter instance, “Studies are needed to elucidate whether the polytherapy itself has resulted in the behavioral problems, or the combination of polytherapy and the underlying brain problem reflects difficult‐to‐control epilepsy, which, in turn, has resulted in the prescription of polytherapy.”

All other recommendations were graded U (for Unproven), “Data inadequate or conflicting; treatment, test or predictor unproven.” These included three where the evidence is ambiguous or insufficient:

• Evidence is conflicted for the impact of early seizure onset on the development of ADHD in children with epilepsy.
• Tolerability for amphetamine in children with epilepsy is not defined.
• Limited evidence exists for the efficacy of atomoxetine and amphetamines in children with epilepsy and ADHD.

There were also nine U-graded recommendations based solely on expert opinion. Most notable among these:

• Screening children with epilepsy for ADHD beginning at age 6.
• Reevaluation of attention function after any change in antiepileptic drug.
• Screening should not be done within 48 hours following a seizure.
• ADHD should be distinguished from childhood absence epilepsy based on history and an EEG with hyperventilation.
• Multidisciplinary involvement in transition and adult ADHD clinics is essential as many patients experience challenges with housing, employment, relationships, and psychosocial well‐being.

REFERENCES

Stéphane Auvin et al., “Systematic review of the screening, diagnosis, and management of ADHD in children with epilepsy. Consensus paper of the Task Force on Comorbidities of the ILAE Pediatric Commission,” Epilepsia (2018), doi: 10.1111/epi.14549. .