Factors associated with epileptiform EEG patterns in Nigerian epileptics.

We reviewed electroencephalographic (EEG) records of 626 epileptic patients for the frequency of epileptiform patterns (EP). The purpose of this study was to determine the factors determining the occurrence of EP. Epileptiform pattern was detected in 46% of patients studied. The occurrence of EP was associated with age, seizure type, longer duration of epilepsy, and proximity of EEG examination to last attack. We found no association between seizure frequency, medication status at EEG examination and the occurrence of EP. The yield of diagnostically useful findings in the interictal EEG would be increased if the test is performed as close as possible to the last seizure.