Febrile Seizures after 5 Years of Age : Clinical and Electroencephalographic Characteristics

Moon, Jin Hwa; Lim, Byung Chan; Park, Jee Yoon; Hwang, Hee; Chae, Jong Hee; Kim, Ki Joong; Hwang, Yong Seung

Abstract

PURPOSE: We aimed to investigate the electroclinical characteristics of patients having persistent seizures with fever after 5 years of age, which has not been elucidated well.
METHODS
We identified 101 patients over 5 years (M : F=64 : 37, range: 5.0-11.0), visited our hospital for febrile seizure. Their medical records for clinical features and EEG findings at last seizure were retrospectively reviewed.
RESULTS
The mean onset age of seizure of total patients was 3.0 years (range: 0.3-8.3). The complex features were noted in 15.8%. Family history were in 53.3%. Neurologic abnormalities were in 10.9%. Abnormal EEGs were in 36.7% (generalized spike or polyspike-waves: 10, focal epileptic discharges: 16, others: 3). When we compare the patients of 5.0-5.9 years (Group A, n=48) to the patients after 6 years (Group B, n=53), complex features (20.8% vs 37.8%, p=0.063) and AED treatments (6.3% vs 18.9%, p=0.059) were more common in Group B. Among group B, patients after 8 years were more apt to be treated by AED than youngers (6.1% vs 40.0%, p=0.002). When we compare the patients starting their first seizure before 5.0 years (Group C, n=78) to the patients after 5.0 years (Group D, n=23), Group C had more frequent seizures (6.6 vs 2.3, p= < 0.0001) and family history (58.3% vs 25.0%, p=0.039). Group D had more common abnormal neurologic findings (7.7% vs 21.7%, p=0.057).
CONCLUSION
Febrile seizures in older age group are more associ-ated with complex features, EEG abnormalities and AED treatments. The patients with seizure onset before 5.0 years had more seizure frequency and family histories.