Tehran University of Medical Sciences Journal of Sleep Sciences 2476-2938 1 3 2016 12 06 115 119 EN Fariba Tardast Occupational Sleep Research Center, Baharloo Hospital AND Department of Occupational Medicine, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran Farzaneh Chavoshi Occupational Sleep Research Center, Baharloo Hospital, Tehran University of Medical Sciences, Tehran, Iran Omid Aminian Department of Occupational Medicine, School of Medicine AND Center for Research on Occupational Diseases, Teh-ran University of Medical Sciences, Tehran, Iran 2016 11 27 Background and Objective: Higher concentration of systemic inflammatory markers is reported in patients with obstructive sleep apnea (OSA). Levels of inflammatory markers may be associated with severity of OSA. Objective of this study was to evaluate the correlation between level of inflammation markers and OSA severity. Materials and Methods: Fifty six patients with symptoms and signs of OSA free of prevalent medical conditions including cardiovascular disease, diabetes mellitus, and hypertension were recruited in this study. Full night polysomnography (PSG) was performed for all the study participants. Participants’ blood samples were taken to analyze serum concentrations of Creactive protein (CRP) and erythrocyte sedimentation rate (ESR) in the morning after PSG. Results: The mean age of participants was 40.32 ± 10.78 years with mean body mass index (BMI) of 28.72 ± 4.96 kg/m2. 46 participants (82%) were male. Based on Apnea/Hypopnea Index (AHI), 43 participants (76%) had AHI ≥ 5. Signifi-cant difference was found between serum CRP levels in patients with and without OSA (P = 0.03). However, no signif-icant association was observed in terms of ESR levels between the study groups. After adjustment for age, BMI, neck circumference, and heart rate, CRP had no significant difference between the two study groups. In linear regression model, only BMI was correlated with CRP. Conclusion: This study indicated that BMI is an independent risk factor for elevation of CRP in patients with OSA. Further researches are needed to explore the effects of sleep-related hypoxia on inflammatory serum markers. https://jss.tums.ac.ir/index.php/jss/article/view/55 https://jss.tums.ac.ir/index.php/jss/article/download/55/35