2003 OPEN FORUM Abstracts
THE EXPRESSION OF CIRCULATING sICAM-1, sVCAM-1 AND IL-13 IN OSAHS PATIENTS BEFORE AND AFTER CPAP TREATMENT
GUO Xiheng, Chen W, Baosen P, Yanling Mao, Hongyu Z, Weimin K, Xiaotao
W, Li L, Xinzhi W
Beijing Chaoyang Hospital-Beijing Institute of Respiratory Medicine
Affiliated Capital University of Medical Sciences
Beijing 100020, P.R. China
Introduction: Obstructive sleep apnea-hypopnea syndrome (OSAHS) is common in middle-aged population. As one of the most important potential risk factors, OSA-induced hypoxic stress might be involved in the etiology of cardiovascular disorders by activating adhesion molecules. We hypothesized transient hypoxic stress caused by OAS would increase circulating soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule (sVCAM-1) and interleukin-13 (IL-13) which have been shown to be associated with the development of atherosclerosis. In addition, we investigated whether continuous positive airway pressure (CPAP) treatment could affect the expression of soluble adhesion molecules.
Methods: A prospective study of fifty-six consecutive patients with OSAHS diagnosed by nocturnal polysomnogram (PSG) was carried in our sleep lab. Thirty-two subjects without OSAHS and CAD matched to OSAHS group for age, gender, body mass index (BMI) were as controls. All OSAHS patients underwent PSG before and after one week CPAP therapy. Venous blood samples were collected before sleep at 21:00 and after sleep study at 7:00 in the morning in both groups and after one week CPAP treatment in OSAHS patients to assay for human sICAM-1, sVCAM-1, IL-13 levels with commercially available enzyme-linked immunosorbent assay kits.
RESULTS: Before sleep at 21pm, sICAM-1, sVCAM-1, IL-13 of OSAHS patients were significantly higher than those of controls. There were not statistic differences before and after sleep in controls. After experience 7 hours repeated OSA sleep, sICAM-1, sVCAM-1, IL-13 increased significantly compared with before sleep and controls. The increased levels of sICAM-1, sVCAM-1, IL-13 correlated with the AHI and the oxygen desaturation index but not with the severity of hypoxemia or the frequency of arousals. After first night effective CPAP, significantly reduction of ICAM-1 and VCAM-1, but not IL-13 was observed in OSAHS group. After one-week therapy, sVCAM-1 levels did not change significantly, while the mean sICAM-1 level decreased further.
Conclusions: OSAS-induced hypoxia activates adhesion molecules and the expression of proinflammatory mediators, resulting in circulating sICAM-1, sVCAM-1, IL-13 rise. These adhesion molecules induced by Repeated OSA and transient hypoxia may play one of key roles of the development of atherosclerosis. CPAP therapy can reverse OSA-induced hypoxia and reduce generation of sICAM-1, sVCAM-1, IL-13. Effective treatment of OSAHS can be, therefore, a potential approach to decrease risk of the progression of OSAS-associated cardiovascular diseases.