Is the Oxidative Stress in Obstructive Sleep Apnea Associated with Cardiovascular Complications?—Systematic Review

Obstructive sleep apnea (OSA) is a prevalent, underdiagnosed disease and is considered an independent risk factor for cardiovascular disease. The exact mechanism of cardiovascular complications (CVC) development as a complication of OSA is not entirely understood. Oxidative stress is suspected to be the essential factor in initiating various comorbidities in OSA. Biomarkers of nonenzymatic lipid and protein peroxidation, DNA repair and antioxidant capabilities measured in serum, plasma and urine are frequently used to assess the presence of oxidative stress. We conducted a systematic review and quality assessment of available observational analytic studies to determine whether there is an association between oxidative stress and OSA in patients with prevalent CV disease compared to (a) patients with prevalent CV disease but no OSA, (b) patients with prevalent CV disease and less severe OSA and (c) patients with OSA and no overt CV disease. This systematic review demonstrated that, while oxidative stress is associated with OSA, there was no clear difference in the severity of oxidative stress between OSA patients with or without cardiovascular complications.