Electrical Grounding and Sleep Quality in Hospitalised Patients With Cancer

Overview

Sleep disturbance is one of the most common and most persistent symptoms in patients admitted for cancer care, and the options available during a short hospital stay are limited. The human body is electrically conductive, so an alternating potential - known as body voltage - is induced on the skin by mains wiring and appliances near the bed. Body voltage can be lowered by connecting the body to earth, and higher body voltage has been reported to be associated with lower vagal (parasympathetic) tone. This randomised, sham-controlled trial tested whether nightly electrical grounding improves sleep quality in hospitalised patients with cancer who also have clinically significant insomnia. Participants wore a hydrogel patch on the forehead connected by a cord either to a true earth connection or to an externally identical cord that did not complete a conductive circuit. Grounding was applied on two consecutive nights in the oncology ward and then nightly at home until the outpatient follow-up visit. Body voltage was measured before and during grounding in both settings, so that the trial could verify objectively whether the intervention achieved its intended physical effect. Sleep quality, mood, somatic symptoms and daytime sleepiness were assessed by validated self-report questionnaires.

Design. Prospective, randomised, sham-controlled, participant-blinded, parallel two-group trial conducted in the oncology ward of New Taipei Municipal TuCheng Hospital. Allocation. Participants were allocated to true grounding or sham grounding by a randomised block design generated with the Research Randomizer web service. The true and sham cords were externally indistinguishable, differing only in whether a conductive connection was completed internally; participants were therefore blinded to allocation. Investigators who applied the intervention and measured body voltage were necessarily aware of allocation. Intervention. Grounding was delivered through a medical-grade hydrogel patch of approximately 4 x 5 cm applied to the forehead and connected by a grounding cord, with the impedance of the completed circuit limited to less than 100 ohms. In hospital the cord was connected to the earth terminal of the bedside mains outlet; at home it was connected to a metal window frame, because domestic outlets in Taiwan do not reliably provide a standard earth terminal. Grounding was applied from 21:00 to 06:00 on two consecutive nights in the ward, suspended until discharge, and then applied nightly at home for at least six hours until the outpatient follow-up visit. Body voltage. The alternating potential at the fingertip was measured with a digital multimeter while the participant lay in bed, both before and during grounding, on each in-hospital study night and once at home. Remote bedroom assessment. Within two days of discharge a researcher conducted a video call to record the electromagnetic environment of the bedroom using a purpose-designed questionnaire, and to teach the participant to measure body voltage and to ground safely at home. Statistical analysis. The primary between-group treatment effect was estimated by analysis of covariance, regressing each follow-up score on allocation arm with the corresponding baseline score as covariate. Every model was repeated on rank-transformed data as a sensitivity analysis. All tests were two-sided at the 5% level.