Upper Airway Resistance Syndrome (UARS)

Upper Airway Resistance Syndrome (UARS) is similar to obstructive sleep apnea. During sleep the muscles of the airway become relaxed reducing the diameter of the airway resulting in labored breathing . Typically, the airway of a UARS patient is already restricted or reduced in size, and this natural relaxation during sleep reduces the airway opening increasing resistance to breathing. It can be likened to trying to breathe through a straw while sleeping.

The increased airway resistance to breathing during sleep in this disorder does not lead to a complete stoppage of breathing (apnea) but instead leads to an arousal of the brain. The patient is usually unaware of this brain arousal since they remain physically asleep. Repeated, multiple nighttime brain arousals result in abnormal sleep and daytime sleepiness. Patients typically complain of excessive daytime sleepiness, fatigue, an inability to concentrate, unrefreshing sleep, frequent awakenings, and chronic pain or a general achiness.


To diagnose UARS a sleep study would need to be performed using a probe to measure esophageal pressure. However, even if no probe is used there are indications on a standard sleep study of UARS. A typical result would show no or very few apneas or hypopneas but multiple brain arousals. In addition snoring is commonly present. If you have had a sleep study that did not indicate you have sleep apnea but you still feel tired you may have UARS.