Chronic epilepsy with complex partial seizures is not always medically intractable--a long-term observational study.

OBJECTIVE

To study the prognosis of patients with complex partial seizures (CPS) with or without simple partial (SPS) and secondarily generalized tonic-clonic seizures (GTCS) and to analyze the factors related to the degree of medical responsiveness.

MATERIAL AND METHODS

A total of 266 adult patients with CPS were included in a hospital based observational survey with a follow-up of 2 to 25 years. Clinical characteristics, seizure frequency, electroencephalography (EEG), cerebral computed tomography (CCT) and magnetic resonance imaging (MRI) findings were analyzed. Patients were categorized according to their degree of medical responsiveness into one of three groups: seizure free, improved control (>50% seizure reduction) and poor control.

RESULTS

Mean age at follow-up was 44.7 years (SD 14.7, range 19-93). Mean age at seizure onset was 18.1 years (SD 14.7, median 15, range 1-79). Complete seizure control was achieved in 40%, improved seizure control in 36% and poor seizure control in 24%. Patients entered remission after a mean period of 15.7 years (SD 12.6, median 13, range 1-54) of active epilepsy. A third of all seizure-free patients were still in remission 6.1 years (SD 5.3, median 3.5, range 1-18) after discontinuation of antiepileptic drugs (AED). Patients with poor seizure control had a significantly younger age at onset (P<0.01), a higher initial seizure frequency (more than 3 per month) (P<0.01), abnormal neurological examination (P<0.01), and were more often mentally handicapped (P<0.01). Multiple logistic regression analysis revealed a high initial seizure frequency, mental handicap and an abnormal neurological examination as independent risk factors for poor seizure control. A positive family history, a history of febrile convulsions and/or psychosis, an abnormal EEG or MRI was not predictive of poor outcome.

CONCLUSIONS

Not all patients with CPS were medically intractable. Seizure remission can be achieved after a long time of active epilepsy. Poor seizure control was associated with a high initial seizure frequency, mental handicap and abnormal neurological examination.