A study about changes in polysomnographic parameters and frequency of cyclic alternating pattern of epilepsy patients

Objective: The aim of this study is to determine the changes of frequency and content in cyclic alternating pattern -which is a periodic, physiologic activity in sleep EEG- and polysomnographic parameters with using video-EEG and polysomnography records of generalized and partial epilepsy patients. With consideration of the contribution to diagnosis and follow-up, to investigate the continuity of these changes in the patients whose EEG?s do not include any epileptiform discharges and also to determine the occurring differences when patients grouped according to seizure frequency has been aimed.Method: Seventy three epilepsy patients diagnosed with epilepsy in Dokuz Eylul University of Medicine Sleep and Epilepsy Center and 19 control subjects in the same age group included this study. All subjects were recorded by video EEG-polysomnography for 8 hours. After the first evaluation of the records, the subjects with psychogenic nonepileptic seizure, parasomnia, obstructive sleep apnea syndrome, periodic leg movements or low sleep efficiency excluded from the study because of the probability to affect the results. Finally the results of video EEG, polysomnografic evaluation and CAP analysis of 57 epilepsy patients (31 generalized, 26 partial) and 16 healthy subjects were compared between groups.Results: After the evaluation of EEG records the rate of abnormality was %38.7 in generalized epilepsy group and %42.3 in partial epilepsy group. When polysomnographic parameters compared between three groups; total sleep time and NREM I sleep period was found longest in partial epilepsy group and the shortest in control group; REM sleep period was found shortest in partial epilepsy group and the longest in control group. The mean CAP rate was statistically significantly higher in generalized epilepsy group from the other two groups. Generalized epilepsy patients with no abnormal potential in EEG had also higher CAP rates compared with control group. There was no difference in CAP rates between the partial epilepsy and control groups. When the patients were separated to three groups according to seizure frequency, even there was no statistically significance, with the advance of seizure frequency the probability of finding EEG abnormality and mean CAP rate increase was remarkable.Conclusion: There are differences between generalized epilepsy patients and healthy individuals in macro and microstrucres of sleep and these differences are independent from epileptic discharges. In partial epilepsy patients the change in macrostructure of sleep is evident, but there is no observation of the change in microstructure of sleep.