The relationship between obstructive sleep apnea, nocturia, and daytime overactive bladder syndrome in women.

Abstract

The purpose of this study was to corroborate the association between obstructive sleep apnea (OSA) and nocturia in a clinical sample of urogynecologic patients and to explore whether night-time urine concentration predicts the presence of OSA. Patients with nocturia and control subjects underwent a home sleep study, completed validated nocturia questionnaires, and provided evening and morning urine specimens that were analyzed for osmolarity. Twenty-one patients with nocturia (16 of whom also had daytime overactive bladder [OAB] symptoms) and 10 control subjects were studied. OSA was present in 17 of 21 women (81%) with nocturia: 13 women (81%) with OAB, 4 women (80%) with nocturia/no OAB, and 4 control subjects (40%; P < .001). The percentage of rapid eye movement sleep time was correlated inversely with nocturic frequency (rho = -.51; P < .004). The presence of diluted nighttime urine in a patient with nocturia was 88% sensitive for the presence of OSA. We should consider a diagnosis of OSA in all patients with nocturia, even those patients with daytime OAB.