Disruption of normal gastric myoelectric functioning by sleep

Study Objectives: The aim of this study was to assess the effects of sleep on gastric myoelectric activity as measured by electrogastrography in healthy individuals. The goal was to elucidate the role of central influences in the regulation of normal gastric functioning. Design: Electrograstrogram (EGG) was recorded during polysomnographically monitored waking and sleep. Setting: Sleep laboratory. Participants: 17 healthy volunteers. Measurements and Results: EGG parameters were computed for 20-minute segments of pre- sleep waking, stage 2 sleep, stage 4 sleep, and REM sleep using both overall and running spectral analysis of EGG data. The dominant power decreased significantly from waking (31.4 ± 1.4 dB) to all sleep stages (23.1 ±1.5 dB during stage 2; 24.7 ± 1.4 dB during stage 4; 24.3 ± 1.3 dB during REM sleep). The percentage of 2-4cpm activity decreased significantly during NREM sleep (64.6 ± 7.6% during stage 2 sleep; 57.5 ± 5.5% during stage 4 sleep) compared to its waking value (90.8 ± 3.2%), but not compared to REM sleep (74.1 ± 5.4%). The instability coefficient of the dominant frequency increased significantly from waking (0.19 ± 0.03) to all sleep stages (0.36 ± 0.05 during stage 2 sleep; 0.47 ± 0.05 during stage 4; 0.34 ± 0.05 during REM sleep). No significant differences between the sleep stages were found for any measure. Conclusions: Sleep is associated with increases in gastric dysrhythmia and instability of the gastric slow wave frequency when compared to waking. These findings suggest that the intrinsic electrical activity of the stomach is significantly influenced by central nervous system mechanisms, and support the notion of a brain-gut axis.