Modest Effects of Low-frequency Electrical Stimulation on Patients with Chronic Insomnia in an Open Trial

Background and ObjectiveaaThe purpose of this study, was to investigate the effects of low-frequency transcutaneous electric nerve stimulation (TENS) on chronic insomnia. Treatment options in patients with chronic insomnia are limited to medications, and cognitive behavioral therapy. MethodsaaFifty-four chronic insomniacs received TENS with low-frequency, applied on trapeziums muscles for at least 30 minutes to 1 hour before sleeping, more than 5 days weekly, for 4 weeks. The Pittsburgh Sleep Quality Index, Insomnia Severity Index, Epworth Sleepiness Scale, Hospital Anxiety and Depression Scale, and quantitative electroencephalography at waking state, were obtained pre and post treatment. ResultsaaPoor sleep quality and insomnia severity decreased significantly, and relative delta power in the occipital region, also decreased after TENS. Overall treatment response rate was 57.5%, and predictive factors of treatment response were daytime sleepiness, as well as depressive and anxious mood. Relative delta power in occipital region of responders significantly decreased over time, while that of non-responders did not change This seemed to be associated with insomnia symptom improvement, and resulting daytime alertness. ConclusionsaaLow-frequency electrical stimulation, was modestly effective in chronic insomnia patients. Our results provide an alternative option of insomnia treatment, for future study. Sleep Med Res 2019;10(1):17-24