Oxidative stress in obstructive sleep apnea

Area of Science:

• Cardiovascular Disease Research
• Sleep Medicine
• Biomarkers of Oxidative Stress

Background:

• Obstructive sleep apnea (OSA) is a prevalent sleep disorder associated with cardiovascular disease.
• Oxidative stress is implicated in the pathogenesis of cardiovascular complications.
• Understanding the link between OSA severity and oxidative stress is crucial for risk stratification.

Purpose of the Study:

• To examine the association between obstructive sleep apnea (OSA) severity and oxidative stress.
• To identify factors contributing to the relationship between OSA and oxidative stress.
• To investigate urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) as a marker of oxidative stress in OSA.

Main Methods:

• A cross-sectional study involving 128 participants undergoing OSA screening or treatment.
• Polysomnography was used to assess sleep-disordered breathing severity.
• Urinary 8-OHdG excretion was measured as an in vivo marker of oxidative stress.

Main Results:

• Subjects with severe OSA (apnea-hypopnea index [AHI] ≥ 30) exhibited significantly higher urinary 8-OHdG excretion compared to those with nonsevere OSA (AHI < 30).
• Urinary 8-OHdG excretion correlated with multiple sleep-disordered breathing parameters, including AHI, apnea index, oxygen desaturation index (ODI), and respiratory arousal index.
• After adjusting for confounding factors, only ODI remained significantly correlated with urinary 8-OHdG excretion.

Conclusions:

• The severity of obstructive sleep apnea (OSA) is independently associated with oxidative stress.
• The oxygen desaturation index (ODI) is the most significant parameter of sleep-disordered breathing related to oxidative stress in OSA.