PT - JOURNAL ARTICLE AU - B. Jurado-Gámez AU - M.C. Fernandez-Marin AU - J.L. Gómez-Chaparro AU - L. Muñoz-Cabrera AU - J. Lopez-Barea AU - F. Perez-Jimenez AU - J. Lopez-Miranda TI - Relationship of oxidative stress and endothelial dysfunction in sleep apnoea AID - 10.1183/09031936.00027910 DP - 2010 Jan 01 TA - European Respiratory Journal PG - erj00279-2010 4099 - http://erj.ersjournals.com/content/early/2010/07/22/09031936.00027910.short 4100 - http://erj.ersjournals.com/content/early/2010/07/22/09031936.00027910.full AB - To evaluate ischemic reactive hyperemia (IRH) in obstructive sleep apnoea (OSA) and its relationship with oxidative stress.We studied 69 consecutive patients referred to our Sleep Unit. Patients with chronic diseases or taking medication were excluded. IRH was assessed before and after the polysomnogram. Morning IRH and oxidative stress markers were compared between patients with (apnoea-hypopnoea index (AHI) ≥5) and without (AHI<5) OSA. Measurements were repeated in 25 severe OSA patients after CPAP therapy.We included 46 OSA patients (AHI 49±32.1) and 23 non-OSA subjects (AHI 3±0.9). The OSA patients showed a significant worsening of morning IRH and a significant increase in malondialdehyde and 8-hydroxydeoxyguanosine. Only the oxygen desaturation index independently explained morning IRH while malondialdehyde showed a weak effect on IRH. In severe OSA patients, IRH improved significantly after CPAP treatment, as did the malondialdehyde, 8-hydroxydeoxyguanosine and protein carbonyls.In OSA patients, endothelial dysfunction and oxidative stress were observed, and IRH worsened after sleep. The increase in oxidative stress was not associated with IRH while intermittent hypoxia was strongly associated with IRH. In severe OSA patients, CPAP treatment improved oxidative stress and endothelial function.