Publications of Faculty of Medicine:Diurnal Variation Of Serum S100 Protein Levels As A Screening Test For Adults With Obstructive Sleep Apnea At Risk Of Hypoxemic Brain Affection Bakr Ras; Khalid Salam * & Adel R Al-Kholy: Abstract

Objectives : The present study tried to investigate the serum levels of SWOB protein at evening and morning as a trial evaluate its relation with obstructive sleep apnea syndrome (OSAS) severity parameters and to define the predictability of its estimation for identification of OSAS patients at risk of hypoxemic brain affection. Patients & Methods : Sixty patients were allocated into three e^ual groups: OSAS Group included OSAS patients free of neurological manifestations. Stroke Group included patients developed stroke and were free of OSAS manifestations and OSAS/Stroke group included patients recently developed stoke and had past history of OSAS. The study also included 20 patients free of OSAS manifestations and had no previous neurological event of cross-matched age and sex as Control group. All patients underwent complete otorhinolaryngologic examination and sleep-history data and a validated measure of daytime sleepiness using the Epworth Sleepiness Scale (ESS) with an ESS Score >10 confirmed the presence of excessive daytime sleepiness and the higher the score, the greater the severity of OSA. Nocturnal pulse oximetry was used for determination of blood Oi saturation (SaOT) and the frequency of desaturation episodes. All patients and controls gave two blood samples; in the evening shortly before bedtime and immediately in the morning after awakening for estimation of serum levels of SWOB protein. Results : Patients included in OSAS+Stroke group had significantly higher ESS score and number of desaturation episodes with significantly lower SaOz compared to those had OSAS only. Morning mean serum levels of SWOB protein was significantly elevated in patients' groups; but non-significantly elevated in control • group compared to evening levels. Both evening and morning samples showed significantly elevated serum SWOB protein in patients' groups compared to control group. In OSAS patients, evening serum SWOB protein levels were non-significantly higher compared to Stroke group but were significantly lower compared to OSAS+Stroke group. On contrary, morning serum SWOB protein levels were significantly higher, but were non-significantly lower in OSAS group compared to Stroke and OSAS+Stroke groups, respectively. Serum SWOB protein levels were significantly higher in OSAS+Stroke group compared to Stroke group in both samples. There was a positive significant correlation between serum levels of SWOB protein estimated in OSAS patients and the severity of OSAS manifested as ESS scores and number of desaturation episodes, while such correlation was negative significant with estimated lowest SaO2 during sleep. ROC curve analysis defined serum SWOB protein level as a sensitive predictor for occurrence of cerebral complications (AAC=0.765) followed by lowest SaOi during sleep (AAC=0.684) and 0.095 pg/l as an accurate cutoff point of morning serum SWOB protein for prediction of possibility of development of cerebral complication with AUC=0.059.