ABSTRACT
The upper airway resistance syndrome (UARS) defines a group of patients with clinical signs and symptoms of excessive daytime somnolence in the absence of obstructive sleep apnea. Snoring is oftentimes present in these patients but is not a necessary symptom of UARS. Patients have increased upper airway resistance, which is characterized by partial collapse of the airway resulting in the increased resistance to airflow. The resistance to airflow is typically subtle and does not result in apneic or hypopneic events; therefore, a normal respiratory disturbance index is recorded. Physical findings include excessive palatal tissue and narrowing of the oropharynx and hypopharynx. An increased respiratory effort is required to maintain airflow to the lungs and may result in multiple sleep fragmentations as measured by very short alpha electroencephalogram (EEG) arousals (1). Repetitive alpha arousals during sleep are thought to be responsible for symptoms of excessive daytime somnolence, which is the principal symptom of UARS.
