Effect of CPAP on oxidative stress and circulating progenitor cell levels in sleep patients with apnea-hypopnea syndrome.

BACKGROUND The sleep apnea-hypopnea syndrome is associated with elevated oxidative stress, which is associated with reduced levels and functional impairment of progenitor cells. OBJECTIVE To evaluate whether one month of CPAP treatment affects circulating-progenitor-cell levels and oxidative stress in patients with sleep apnea-hypopnea syndrome. METHODS We enrolled 13 patients with sleep apnea-hypopnea syndrome who required nasal CPAP. We evaluated white-blood-cell oxidative stress and CD45-, CD34+, KDR+, and CD133+ cell levels via flow-cytometry, before and one month after CPAP treatment. RESULTS Superoxide anion and hydrogen peroxide were reduced, and markers of protection against oxidative stress were increased after CPAP. Progenitor-cell levels increased significantly after CPAP. There was a significant negative correlation between CD45-, CD34+, KDR+, and CD133+ cell levels and the severity of sleep apnea-hypopnea syndrome and superoxide anion. CONCLUSIONS CD45-, CD34+, KDR+, and CD133+ cell levels rose significantly and reached values close to those in the control group after one month of CPAP. This change was accompanied by a significant decrease in oxidative stress, and no change in anthropometric or metabolic variables, including insulin resistance, weight, blood pressure, or lipid levels; consequently, the increase in progenitor-cell levels might be attributable to reduced oxidative stress.