0558 Could Treatment of Sleep Apnea Worsen Somnolence?

Abstract Introduction Patients presenting with daytime somnolence need to be evaluated for common etiologies including sleep-related breathing disorders, shift work disorder, insufficient sleep, insomnia and disorders of hypersomnolence. Sleep disordered breathing (SDB) is one of the most common causes of daytime sleepiness. We postulate that treatment of SDB may actually worsen symptoms, if associated with poor sleep due to positive airway pressure (PAP) therapy. Methods N/A Results A 49-year-old female presented to our clinic with increased daytime somnolence. She was diagnosed with obstructive sleep apnea (OSA) at an outside center 3 years ago and was started on auto PAP therapy with pressure settings at 6-10 cmH2O. She had 100% usage, 95th percentile pressure of 9 cm H2O, and a residual Apnea Hypopnea Index (AHI) of 1.1. The patient reported excessive daytime sleepiness, with an Epworth Sleepiness Scale of 16, requiring a daily 3-hour nap. Further sleep history revealed that she had multiple nocturnal awakenings due to discomfort with PAP therapy, including mask related issues causing sleep disruption. Several mask adjustments did not result in any sleep improvement. We decided to re-evaluate her with an in-lab polysomnography. Diagnostic data revealed an overall AHI of 1.6, supine AHI of 12.0, and lateral AHI of 1.5. Mean oxygen saturation was 94.6% with a nadir of 89.0%. The patient was advised to discontinue PAP therapy, and to sleep on her sides, which led to improvement in her sleep quality and daytime sleepiness. Conclusion Positional OSA, defined by greater than 50% increase in AHI in supine position compared to non-supine position, with or without AHI less than 5 in non-supine position, is seen in up to 50-60% of patients with OSA. In addition, intolerance to CPAP has been noted in 29-83% of patients. We need to be clinically aware of the potential effect of PAP devices, or oral appliances, on sleep disruption among intolerant patients. Among this group, conservative therapies like positional therapy or weight loss may be more effective for symptom management, especially for mild SDB. Support (if any)