Increased Epilepsy Prevalence in Adults with 22q11 Deletion Syndrome (P1.236)

Objective: To quantify the prevalence of both provoked and unprovoked seizures in an adult population of patients with 22q11.2 deletion syndrome (22q11.2DS). Background: 22q11.2DS is one of the most common recurrent interstitial deletion syndromes in humans. Patients with 22q11.2DS can present with variable phenotypes, affecting multiple organs and tissues. There is increasing evidence that children and adolescents with 22q11.2DS are at higher risk for both provoked and unprovoked seizures relative to the general population. However, few studies have systematically examined seizures in adults with 22q11.2DS. Design/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: Of 202 patients, 32 (15.8%) had a documented history of seizure. The majority of adults had acute symptomatic seizures (71%), usually associated with hypocalcemia and antipsychotic use. Eleven patients (5.5%) met diagnostic criteria for epilepsy. Four patients (2.0%) had received a diagnosis of genetic generalized epilepsy. Conclusions: The prevalence of provoked seizures in adults with 22q11.2DS is higher than in the general population. Hypocalcemia continues to be risk factor for adults, but differently from children, adults with 22qDS are more exposed to psychotropic medications and are more vulnerable to seizures caused by them compared to the general population. These patients are also more likely to develop genetic generalized and focal epilepsy, structural epilepsy (due to malformation of cortical development, trauma, stroke). Further prospective studies are warranted to investigate how 22q11.2 microdeletion leads to an overall decreased seizure threshold. Study Supported by: Brain and Behavior Research Foundation (formerly NARSAD) Disclosure: Dr. Wither has nothing to disclose. Dr. MacDonald has nothing to disclose. Dr. Borlot has nothing to disclose. Dr. Butcher has nothing to disclose. Dr. Chow has nothing to disclose. Dr. Bassett has nothing to disclose. Dr. Andrade has received personal compensation for activities with Eisiai and UCB as an advisory. Dr. Andrade has received research support from Sunovion.