以腦波及心律變異性分析為基礎之失眠評估

Insomnia has become a severe health problem recently. So analyzing the physiological differences in sleep between insomnia and normal people to assist clinical treat is an important work. Some researches indicate that sleep stage is related with electroencephalogram (EEG) and heart rate variability (HRV). Low frequency power of HRV is obvious in Rapid Eye Movement (REM), in contrast high frequency power of HRV is more dominant in Non-Rapid Eye Movement (NREM). But few researches investigate whether sleep disorder has different EEG and HRV or not. The goal of this study is to reveal the differences of EEG and HRV between insomnia and normal subjects and give some reasonable explanation for sleep disorder.
We obtained polysomnography (PSG) data of 11 normal subjects and 14 insomnia cases from a sleep center in a hospital. The data according to sleep staging algorithm were divided into REM and NREM periods, in addition to fast wave and slow wave periods in NREM stage. The results revealed that LF (Low Frequency; LF),, LF (nu) (normalized Low Frequency; LF(nu)) and LF/HF (LF/HF ratio) were significantly lower respectively in NREM comparing with those in REM for normal subjects, but no significant differences in insomnia cases. In EEG, the power of beta wave in normal subjects was significantly increased in REM than in NREM, but it appeared an opposite result in insomnia cases. Moreover, the normal subjects had stronger delta wave power at NREM stage, but this difference didn't exist in insomnia cases. Therefore insomnia indeed displayed abnormal regulation in autonomic control and brain activity for sleep process in this study. This finding may provide a new direction to understand insomnia.