Neurodevelopmental Disorders: Overlapping Etiologies

Epilepsy and psychotic illnesses are strongly associated within individuals and families, according to results of a recent study.

It is well established that epilepsy patients are at increased risk of developing a psychotic illness, such as schizophrenia and schizophrenia-like-psychosis. In a study published in the May 1, 2012, issue of Biological Psychiatry, researchers based at the Royal College of Surgeons in Ireland reported that epilepsy and psychotic illness are strongly associated within individuals. They also determined that psychosis co-occurs with all types of epilepsy.

After examining data from 9653 families and more than 23,000 offspring, the researchers determined that this association clusters within families. Further, if someone has either epilepsy or schizophrenia, his or her child is more likely to have epilepsy (1.6 to 2.7 times the risk) or the psychoses (2 times the risk) even if the conditions are not comorbid in the parent. Maternal epilepsy was found to confer a slightly greater risk of psychosis in children than paternal epilepsy, raising the possibility that maternal exposure to antiepileptic drugs (AEDs) or antipsychotics may affect offspring as well.

Thus, epilepsy and schizophrenia have shared genetic roots, and the disease expression in individual patients is probably influenced by other genetic, environmental, or accumulating genetic mutations.

Both of these diagnoses create the need for lifelong treatment with prescription drug therapy. AEDs are often associated with drug interactions, complicated pharmacokinetics, and adverse drug reactions. Many new AEDs have become available in recent years, creating a need for post-marketing vigilance.

Pharmacists need to talk to their patients who have epilepsy with (or without) comorbid psychiatric illness. Asking about tolerability, possible side effects, and adherence can help identify problems that can reduce adherence or create medication misadventure.

Ms. Wick is a visiting professor at the University of Connecticut School of Pharmacy and a freelance writer from Virginia.