Circadian Rhythm Of Epileptic Spasms Of Infantile Spasms

Objective:To explore the diurnal and sleep/wake patterns of epileptic spasms in Chineselnfantile spasms patients and the peak hours during continuous 24 hours which benefit to understand the circadian patterns of epileptic spasms.The research on the circadian rhythm of seizures may provides a new idea for the pathophysiology and the treatment of infantile spasms.Methods:We collect patients with infantile spasms undergoing video-electroencephalography(EEG)monitoring over a 2-year period were reviewed for presence of epileptic spasms and analyze for their occurrence during the day(6 a.m.to 6 p.m.)or night,out of wake or sleep,and in 3-h time-blocks throughout the day.Exact epileptic spasm,the presence or absence of magnetic resonance imaging lesion,the developmental or acquired etiologies,different age at onset were also recorded.Statistical analysis of seizure occurrence in time bins was carried out using nonparametric test.P-values<0.05were taken as significant.Results:We analyzed 184 clusters of epileptic spasms in 41 infantile patients(29 boys;younger than 2 years old).Epileptic spasms occurred predominantly during wakefulness(p<0.001)and during daytime(p<0.01).Epileptic spasms occurred most frequently between 6a.m.and noon and between 3p.m.and 6p.m.(p<0.01).Thirteen patients had 68epileptic spasms(63.0%)with normal MRIs and the twenty-eight patients had 116 epileptic spasms(37.0%)with MRI-identifiable lesions.Normal MRIs seizures occurred most frequently between 9a.m.and noon(p<0.05),while MRI-identifiable lesions occurred most frequently between 6a.m.and noon and 3p.m.and 6p.m.(p<0.01).Twenty-three patients had 103epileptic spasms(56.0%)with developmental etiologies and the eighteen patients had 81 epileptic spasms(44.0%)with acquired etiologies.But the developmental etiologies had more seizures between 9a.m.and noon(p<0.05)as the same as the acquired etiologies seizures.Following onset age stratification,younger than 6 months had more seizures between 9a.m.and noon and 6a.m.and 9a.m.(p<0.01),while older than 6 months had more seizures between 9a.m.and noon and 3p.m.and 6p.m.(p<0.05).Conclusions:Epileptic spasms has apparent circadian rhythm.The study on the circadian rhythm of seizures may provides a new idea for the research of pathophysiology and treatment.Besides further research on the mechanisms are needed.