Assessment of fibrinogen levels in obstructive sleep apnea patients

Özet

Fibrinogen increases in the acute inflammatory response since it is an acute-phase reactant. Fibrinogen was defined as an independent risk factor for cardiovascular diseases. We aimed to assess the alterations in plasma fibrinogen levels in patients with obstructive sleep apnea syndrome (OSAS) by comparing them with the control cases and determine their relationship with polysomnography (PSG) parameters. The study included 125 newly diagnosed patients with moderate to severe OSAS (defined as apnea-hypopnea index [AHI] ≥ 15) and 82 non-apneic control subjects (AHI<5). A full-night polysomnography was performed in all patients. After the sleep study, blood samples were drawn between 8:00 and 9:00 in the morning to measure fibrinogen levels. In OSAS patients, plasma fibrinogen levels were significantly higher than that of the control cases (4.4±0.12 g/L vs. 3.5±0.16 g/L; p:0.025). Positive correlations were reported between plasma fibrinogen levels and Epworth Sleepiness Scale (ESS) scores (r=0.299, p=0.006), age (r=0.327, p=0.003), body mass index (BMI) (r=0.391, p<0.001), average oxygen desaturation (r=0.258, p=0.019), oxygen desaturation index (r=0.279, p=0.009), time at <90% oxygen saturation (r=0.251, p=0.026), and arousal index (r=0.219, p=0.045). There was a negative correlation between plasma fibrinogen levels and the average oxygen saturation during sleep (r=-0.255, p=0.029). Increased ESS and BMI were related to elevated plasma fibrinogen levels, independent of AHI, in multiple regression analysis. Plasma fibrinogen levels are related with BMI and ESS that supports the link between hypoxia and inflammation. We suggest that elevated fibrinogen levels may be an essential factor in the pathogenesis of vascular disease in patients with OSAS.