Surgical treatment for obstructive sleep apnea: effect on sleep architecture.

Purpose: Investigate the effect of surgical treatment of obstructive sleep apnea syndrome (OSA) on sleep architecture.

Methods: Observational retrospective analysis of polysomnographic data of adults diagnosed with OSA, submitted to surgical treatment. Median (25-75th percentile) was used to present the data.

Results: Data were available for 76 adults, 55 men and 21 women, with median age of 49.0 years (41.0-62.0), body mass index of 27.3 kg/m (25.3-29.3) and AHI of 17.4 per hour (11.3-22.9) before surgeries. Preoperatively, 93.4% of patients had an abnormal distribution of at least one of the sleep phases. After surgical treatment, we found a significant increase in median N3 sleep percent from 16.9% (8.3-22-7) to 18.9% (15.5-25.4) (p = 0.003). Postoperatively, 18.6% patients that had an abnormal preoperative N1 sleep phase distribution had a normalization of this sleep phase, as also occurred to N2, N3 and REM sleep phases in 44.0%, 23.3% and 63.6% of patients, respectively.

Conclusion: This study aims to show the impact of OSA treatment, not only on respiratory events but also on other polysomnographic data often underestimated. Upper airway surgeries have shown to be effective in sleep architecture improvements. There is a trend for sleep distribution normalization, with increase of time spend in profound sleep.