Gastroesophageal Reflux during Sleep: Does REM Sleep Provide a Protective Effect?
Damera, Sriharsha MD; Goodrich, Suanne PhD; Fernstrom, Paula BS; Hasselgren, Goran MD; Orr, William C. PhD
Lynn Health Science Institute, Oklahoma City, OK; AstraZeneca, Molndal, Sweden and University of Oklahoma Health Sciences Center, Oklahoma City, OK.
Purpose: The purpose of this study was to assess the prevalence of reflux events over each third of the sleeping interval and to assess whether reflux events may be affected by sleep stages.
Methods: Twenty-four individuals with self-reported sleep disturbance and 40 controls without symptoms of sleep disorders or heartburn were studied for two nights via polysomnographic evaluations that included distal esophageal pH recordings. Two PSG recordings were separated by at least two weeks for each participant. For this study we analyzed a subset of participants who had at least one reflux event (N = 15). Out of 15 subjects 6 were unrefreshed sleepers with slef-reported sleep disturbance and 9 were controls with no sleep disturbance.
Results: A total of 40 reflux events were noted in sleep, out of which 20 events are noted in the first 3rd of the sleeping interval, 16 events noted in the second 3rd of the sleeping interval and 4 events noted in the final 3rd of the sleeping interval. The total number of events in the first 3rd of the sleeping interval were significantly higher than final 3rd of the sleeping interval (P < .05). There was no significant difference in the number of reflux events in the first and second parts of the sleeping interval. We also analyzed the data to determine if there was any impact of sleep stage on reflux events. We calculated the percent of sleep stages in each third of the night. The amount of deep sleep in the 1st third of the sleeping interval is significantly more than the second third (P= .002) and final third of the sleeping interval. (P < .001). The amount of REM sleep in final third of the sleeping interval is significantly greater than in the 1st third of the sleeping interval. (P < .001) and 2nd third of sleeping interval (P= .035). Reflux events persisted into the 2nd third of the sleeping interval when the percent of both REM and deep sleep is very low and stage 2 is dominant. The arousal index didn't significantly differ between the 1st and 3rd part of the sleeping interval. (P= .728)
Conclusion: 1) GER is more common in the first third of the sleeping interval compared to the third portion of the sleeping interval.
2) Reflux events may be affected by the stage of sleep with REM sleep possibly providing a protective effect against GER.© The American College of Gastroenterology 2007. All Rights Reserved.