Occurrence of seizures in hospitalized patients with a pre-existing seizure disorder

Objective. To assess the frequency of seizures in hospitalized patients with a pre-existing seizure disorder.

Patients and Methods. A retrospective review was conducted on all patients with a documented seizure disorder who were hospitalized between January 1, 2002 and December 31, 2007. Children aged < 2 years and hospital admission for seizure control or surgical or obstetric indications were excluded. The first hospital admission of at least 24 hours was identified for each patient. Patient demographics, details of the seizure disorder, details of the hospital admission, and clinically-apparent seizure activity documented during the inpatient stay were recorded from the medical record.

Results. During the 6-year study period, 720 patients with a documented seizure disorder were admitted for at least 24 hours. Thirty-nine patients experienced seizure activity for an overall frequency of 5.4% (95% CI: 3.8-7.1%). Younger age (p = 0.001), greater frequency of baseline seizure activity (p < 0.001), recent seizure activity (p < 0.001), greater number of chronic antiepileptic medications (p = 0.01), and admission for neurological (p = 0.03) conditions were associated with increased frequency of seizure activity during hospitalization.

Conclusions. The majority of seizures occurring in hospitalized patients with a pre-existing seizure disorder appear related to the patient’s underlying seizure disorder. Because patients with frequent seizures on numerous anti-epileptic medications are likely to experience a seizure while hospitalized, it is essential to be prepared to treat seizure activity regardless of the reason for admission.

seizure disorder, hospi-talization, anticonvulsants 

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