Sleep-Related Deglutition in Patients with Sleep Apnea-Hypopnea Syndrome

Abstract

Objectives: We investigated sleep-related deglutition in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS). Methods: Deglutition during sleep was examined in 10 patients with a mean (±SD) age of 48 ± 11 years who had severe OSAHS (apnea-hypopnea index, 66.6 ± 17.6) via time-matched recordings of polysomnography and surface electromyography of the thyrohyoid and suprahyoid muscles. Results: During sleep, deglutition was episodic, and was absent for long periods. Deglutition did not occur during apnea or hypopnea periods. The mean number of swallows per hour during the total sleep time was 5.4 ± 3.1. The mean period of the longest absence of deglutition was 43.5 ± 14.7 minutes. Most deglutition occurred in association with respiratory electroencephalographic arousal after apnea or hypopnea. Approximately 70% of swallows were followed by inspiration. Deglutition was related to the sleep stage. The mean number of swallows per hour was 6.2 ± 6.1 during stage 1 sleep, 6.0 ± 3.4 during stage 2 sleep, 3.0 ± 5.2 during stage 3 sleep, and 0 during stage 4 sleep. The deeper the sleep stage, the lower the mean deglutition frequency. The mean number of swallows per hour was 4.5 ± 3.0 during rapid eye movement sleep. Conclusions: Deglutition was infrequent and displayed a unique pattern in patients with OSAHS during sleep.