A study on the change in blood pre-adaptation factors among patients with obstructive sleep apneahypopnea syndrome

Abstract

Objective To investigate the changes in serum level of vascular endothelial growth factor (VEGF), nitric oxide (NO), erythropoietin (EPO) and plasma level of carbon monoxide (CO) in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS) and their clinical significance. Methods Sixty-four patients diagnosed as OSAHS by polysomnography (PSG), were divided into two groups according to apnea-hypopnea index (AHI), 20 in mild group [5/h≤AHI≤20/h, with a mean of (12± 5)/hi and 44 in moderate-severe group[AHI > 20/h, with a mean of (63±23)/h]. Blood samples were obtained from all the patients after PSG for measurement of levels of serum VEGF, NO and EPO and plasma CO. Results Levels of serum VEGF [(101±91) ng/L], NO [(10.3±3.3) μmol/L]and plasma CO [(0.56±0. 35) mg/L]in moderate-severe OSAHS group were significantly higher than those in mild group (all P 0.05). Levels of serum VEGF, NO and plasma CO in OSAHS patients positively correlated with AHI and percentage of time with percutaneous arterial blood oxygen saturation lower than 0. 9 (SLT90) of all sleep time (all P 0.05). No correlation between EPO and all the indicators was found (P>0.05). Multiple linear regression analysis showed that LSaO2 was an independent risk factor to affect levels of serum VEGF and plasma CO (R2=0.198, P=0.001, and R2=0.210, P=0.000, respectively) and SLT90 was an independent risk factor to affect serum level of NO (R2= 0. 148, P=0.004) in OSAHS patients. Conclusion Hypoxia at night is a main cause leading to increased level of serum VEGF, NO and plasma CO in OSAHS patients. Key words: Sleep apnea, obstructive; Vascular endothelial growth factor A; Nitrric oxide; Carbon monoxide