Background: Obstructive sleep apnea ) is a condition characterized by repeated episodes of 
partial or complete obstruction of the respiratory passages(1) The standard diagnostic procedure for 
establishing the presence of OSA is the overnight polysomnography(2)
. The development of simple, 
and reliable biomarkers that permit precise screening of at-risk populations is required. So , special 
interest has centered around potential OSA biomarkers. The ideal biomarker should be highly 
sensitive , specific and correlate to severity of OSA.(3) Patients and methods: This study was 
performed on 35clinically suspected OSA patients, and15 non-smoker healthy control persons . 
Patients were recruited from of Minia cardiothoracic university hospital during the period from 
September 2018 to September 2019. All patients were assessed for excessive day time sleepiness by 
Epworth sleepiness score and STOPBANG score, pulmonary function tests (FEV1, FVC and 
FEV1/FVC)% predicted, ABG, and measurements of C reactive protein (CRP) and Erythrocyte 
sedimentation rate (ESR) were done for all patients and control. Results: This study were performed 
on 50 patients 35 cases and 15 control group and showed a Significant elevation in CRP and ESR in 
the case group compared to the control group. Conclusion: The current study showed that there was 
a significant elevation in CRP and ESR in case group versus control group.