Diagnostic Value of Oxygen Desaturation Index in Sarcoidosis Patients Suspected to Have Obstructive Sleep Apnea

sarcoidosis patients are at increased risk for obstructive sleep apnea syndrome (OSAS) probably due to factors such as steroid use, obesity, sarcoid neuropathy and etc. Therefore, we aimed to define the diagnostic value of the oxygen desaturation index (ODI) in predicting OSAS in patients with sarcoidosis. This cross-sectional study was performed in ۸۱ sarcoidosis patients suspected to have OSAS admitted to the pulmonary clinics of the Masih Daneshvari Hospital, affiliated with Shahid Beheshti University of Medical Sciences.Patients were examined using the Epworth Sleepiness Scale (ESS) and the Fatigue Assessment Scale(FAS), and those with FAS score≥ ۲۲ and ESS score > ۱۰ were included. All patients underwent a portable polysomnography(PSG) and a high-resolution pulse oximeter wristwatch simultaneously. Of ۸۱ patients, ۵۷(۷۰.۴%) were female and ۲۴(۲۹.۶%) were male, and the mean age was ۴۸.۹±۱۰.۴ years (range, ۲۸ to ۷۵). The AHI score was positively correlated with ESS and ODI scores (r=۰.۵۱, p<۰.۰۰۱; r= ۰.۸۵, p<۰.۰۰۱, respectively). A positive correlation was found between ODI and ESS (r=۰.۵۷, p<۰.۰۰۱). A kappa coefficient value of ۰.۲۶ indicated a fair agreement between AHI and ODI scores. The cutoff based on maximal accuracy for ODI to predict AHI ≥۱۵ was ODI ≥۱۵. ODI ≥۱۵ has been indicated to have sensitivity of ۱۰۰%, and hence NPV of ۱۰۰%, specificity of ۹۶.۴%, PPV of ۳۶.۶%, and ۹۹.۹ of accuracy for predicting moderate and severe OSAS. ODI from a high-resolution pulse oximeter wristwatch is a sensitive and specific tool to predict moderate and severe OSAS in sarcoidosis patients.

Keywords:

Sarcoidosis , Oxygen Desaturation , Diagnostic Value , Obstructive Sleep Apnea , Iran.