We attempted to determine (1) whether sleep related acid gastroesophageal reflux (GER) occurs more frequently in the right lateral position compared to the left lateral and supine positions, and (2) whether GER is associated with increased microarousals.
We reviewed 26 nocturnal polysomnograms (NPSG) with esophageal pH monitoring. The inclusion criteria were (1) age over 18 years, (2) a completed NPSG with body position and esophageal pH monitoring. Gastroesophageal reflux (GER) was defined as a pH < 4 for > 30 seconds. The number of GER events, the acid contact time (ACT) with pH < 4, and body position were recorded. The ACT index(ACTI)was defined as the percentage of sleep time in each position with pH <4. Gastroesophageal reflux disease (GERD) was defined as > 4% of sleep period time with pH < 4.
Nineteen subjects met inclusion criteria. There were 12 men and 7 women with a mean age of 47.7±11 (SD) years, mean Epworth sleepiness scale of 12±4.2, apnea+hypopnea index of 5.43±7.33, and a mean BMI of 32.5±7.5 kg/m2. Nine of these subjects had GERD. There was no significant difference in demographics between GERD and non-GERD subjects. Amoung the GERD subjects,ACTI was higher in the right (33.0±16.1) compared to left (2.25±4.07, p=0.0006) and supine (9.1±14.5, p=0.0032) positions. Periods of GER were not associated with increased arousal index compared to total sleep time arousal index (p=1.0). There was no significant difference in arousals for any position between GERD and non-GERD subjects or within groups.
When measured by acid contact time, there is more GER in the right lateral compared to supine and left lateral positions. GER events are not necessarily associated with increased arousals.
Sleeping in the right lateral, but not the supine or left, position may result in worse GER. Asymptomatic nocturnal reflux is not necessarily associated with disrupted sleep.
M.M. El Zein, None.