Evening sock marks as an adjunct to the clinical prediction of obstructive sleep apnea.

Fluid overload shifting from the legs to the upper airway during sleep promotes obstructive sleep apnea (OSA) and interventions targeting fluid attenuate OSA. Fluid shift has been previously measured by bioelectrical impedance, a complex and time-consuming technique not applicable in the daily clinical settings. The aim of this study is to evaluate the presence of clinically detectable fluid overload and shift and its association with OSA. Patients undergoing sleep study for suspected OSA were asked to report the presence of 11 signs/symptoms associated to excessive accumulation of fluid in different parts of the body at different times of the day. Among 392 patients (male: 53%, median [interquartile range] age: 56 years [1], body mass index, BMI: 29 kg/m Clinically detectable fluid overload and shift are prevalent in patients addressed for suspected OSA, and evening sock marks, a marker for leg swelling, is an independent correlate of moderate-to-severe OSA. This sign might contribute to OSA diagnosis and identification of patients likely to be treated by interventions targeting fluid overload and shift.