Upper airway resistance syndrome (UARS) is a recently described form of sleep-disordered breathing that may result in excessive daytime sleepiness (EDS). UARS is defined by repetitive increases in upper airway resistance (IUAR) associated with brief EEG arousals. The diagnosis requires demonstration of IUAR in a crescendo pattern of negative inspiratory pressures on esophageal manometry. We used a negative inspiratory pressure of < — 12 cm H2O in scoring these studies. The resulting arousals are followed by normalization of Pes. However, esophageal manometry is not commonly employed, making UARS difficult to diagnose definitively. Clinicians often make the diagnosis presumptively based on the presence of crescendo snoring associated with respiratory effort-related arousals (RERAs). Limited use of esophageal manometry may underdiagnose UARS and may lead to misclassification of a patient’s hypersomnolence. This misdiagnosis may, in turn, result in the inappropriate use of stimulants as a potential treatment of EDS. These therapies may be ineffective or may mask the underlying sleep disorder.
Although difficult to diagnose, UARS is suggested by EDS associated with snoring in patients who do not demonstrate apneic or hypopneic respiratory events on polysomnography. However, patients may manifest sleep-disordered arousals consistent with UARS even in the absence of snoring, which we define as silent UARS (SUARS). The purpose of this article is to report the occurrence and prevalence of SUARS in our population.