Abstracts

Rationale: Previous studies examining seizure events in patients with 22q11.2 deletion syndrome (22q11DS) have primarily focused on children and adolescents. In this study we investigated the prevalence and characteristics of seizures and epilepsy in an adult 22q11DS population. Methods: The medical records of 202 adult patients with 22q11DS were retrospectively reviewed for documentation of events suspicious for seizures, EEG reports, and MRI findings. Epilepsy status was assigned in accordance to the 2010 International League Against Epilepsy classifications. Results: Fifty eight patients with events suspicious for seizures were further investigated. True evidence of epileptic seizures was found in 34 subjects, 24 (11.8%) of which fulfilled diagnostic criteria for epilepsy. Nine (4.4%) of these patients with epilepsy had an associated underlying structural cause and 15 (7.4%) had non-lesional epilepsy. Seizure types included generalized tonic-clonic seizures (n=21), myoclonic seizures (n=8), focal dyscognitive seizures (n=5), and focal-onset evolving to bilateral convulsive seizures (n=10). Nine patients had a history of more than one type of seizure. The lifetime seizure occurrence (21/35, 60.0 %) in patients that had received antipsychotics was similar to those who had never been treated with an antipsychotic medication (12/23, 56.5 %, p=0.79). Conclusions: The prevalence of epilepsy in 22q11DS adult patients is much higher than in the general population (0/5-1%) and is higher than in children with 22q11DS. Our analysis showed that seizures were not significantly more common in patients with a lifetime history of antipsychotic treatment. Funding: NARSAD