Association between Hypoxia Parameters with White Matter Hyperintensity and Silent Cerebral Infarcts on Brain Magnetic Resonance Images in Patients with Obstructive Sleep Apnea

Abstract

Objective: This study evaluated the association between hypoxia parameters with white matter hyperintensity (WMH) and silent cerebral infarcts (SCI) on brain magnetic resonance (MR) images of patients with obstructive sleep apnea (OSA).

Methods: In this retrospective study, the study group was composed of 453 patients who were evaluated by overnight polysomnography (PSG). Data on hypoxia parameters, such as total sleep duration with oxygen saturation < 90% (ST90), percentage of cumulative time with oxygen saturation < 90% (CT90), and the lowest oxygen saturation (min SaO(2)), were obtained from PSG. The presence of WMH and SCI was evaluated in all participants using brain MR images.

Results: Hypoxia parameters, such as ST90, CT90, and min SaO(2), were significantly associated with WMH (P < 0.001). The multiple regression analysis showed that CT90 was independently associated with SCI (P = 0.038). In addition, when participants were divided into two groups according to CT90 < 10% and CT90 = 10%, age (P = 0.002), sex (P = 0.015), body mass index, Apnea-Hypopnea Index score, Epworth Sleepiness Scale score, and the presence of WMH, hypertension, and diabetes mellitus were significantly higher in the CT90 = 10% group compared with the CT90 < 10% group (P < 0.001 for all parameters). CT90 = 10% increased the risk of WMH 2.34-fold (95% confidence interval, 1.44-3.85; P = 0.006).

Conclusion: The severity of nocturnal intermittent hypoxia may contribute to the pathogenesis of WMH and SCI in patients with OSA.