Introduction: Yoga nidra is referred as " dynamic sleep " which is practised by sages. The relative ease with which it can be practised has made it an acceptable therapeutic option for many diseases. Chronic insomnia is a prevalent condition and non pharmacological treatment is beneficial in these patients. The objective of the study was to find out the role of yoga nidra in chronic insomnia patients. Methods: Chronic insomnia patients (n=8) were taught yoga nidra using standardised method. The patients were administered yoga nidra under supervision for five subsequent days, each session lasting forty minutes, following which they practised daily at home. Patients were reviewed fortnightly. Pittsburgh sleep quality index, insomnia severity scale, Epworth sleepiness scale, pre-sleep arousal scale and their sleep parameters using two weeks sleep diary was collected at baseline and after one month of start of yoga nidra. All patients underwent baseline overnight polysomnography (Somnomedics, Germany) and after one month of start of yoga nidra. Polysomnography record was scored using AASM criteria. Mean sleep onset latency, total sleep time, wake after sleep onset and sleep quality from sleep diary and, total sleep time, sleep efficiency, sleep onset latency, REM onset latency, wake after sleep onset and durations of wake, stage N1, N2, N3 and REM from polysomnography was analysed. SWS (N3) was further manually scored as S3 and S4 and analysed. Results: In sleep diary records, practising yoga nidra for one month caused decrease in sleep onset latency and increase in sleep quality significantly (p<0.05). In polysomnography, there was a significant increase in sleep efficiency and N3 duration (p<0.05) with significant decrease in wake duration (p<0.05). Both S3 and S4 increased significantly (p<0.05). There was a significant improvement in sleep quality index, insomnia severity and pre- sleep arousal scores (p<0.05). Conclusion: Yoga nidra improves slow wave sleep duration and can play an important role in management of chronic insomnia patients.
Keywords: Yoga nidra, Chronic insomnia