Seizures in children with Down syndrome: etiology, characteristics and outcome

Seizures are common among people with developmental disabilities, but not among children with Down syndrome. Studies have shown that only around 5 percent of these children suffer seizures, which are generally caused by brain abnormalities. This study examined whether seizures in children with Down syndrome could be associated with identifiable causes. The records of Down syndrome patients that had suffered at least one seizure before the age of 22 were obtained an analyzed. The records were obtained from three institutions and covered the years 1978 to 1987. Of 737 patients, 47 had suffered at least one seizure. The event that triggered the seizure was known in 29 of the 47 cases. Cardiovascular disease was associated with 12 cases, perinatal complications with seven cases, infections with seven cases, head trauma with two cases, and chemotherapy with one case. For the children with a known cause for the seizures, the seizures were more likely to begin before age three or after age 13. The ages were much more evenly distributed for cases where the seizure was without a known cause. Generalized tonic/clonic types of seizures were the most commonly seen type in both groups. Electroencephalograph (EEG) results were useful in classifying the type of seizure, but not its cause. Patients that either had cardiovascular disease or perinatal problems usually continued to have seizures. The seizures caused by infection were not persistent. Anticonvulsant drug therapy was generally successful in patients with persistent seizures. These results indicate that in many cases, the underlying cause of seizures can be identified in Down syndrome children. Such identification can help in making treatment decisions. (Consumer Summary produced by Reliance Medical Information, Inc.)