Journal of Neurological Sciences (Turkish) 2016 , Vol 33 , Num 3
Association between Hypoxia Parameters with White Matter Hyperintensity and Silent Cerebral Infarcts on Brain Magnetic Resonance Images in Patients with Obstructive Sleep Apnea
1Başkent Üniversitesi Tıp Fakültesi, Nöroloji, Antalya, Turkey
2Başkent Üniversitesi Tıp Fakültesi, Kulak Burun Boğaz, Antalya, Turkey
3Başkent Üniversitesi Tıp Fakültesi, Göğüs Hastalıkları, Antalya, Turkey
4Başkent Üniversitesi Tıp Fakültesi, Radyoloji, Antalya, Turkey
5Başkent Üniversitesi Tıp Fakültesi, Nöroloji, Ankara, Turkey
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 SaO2), 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 SaO2, 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. Keywords : Sleep apnea, snoring, oxygen saturation, hypoxia, stroke, magnetic resonance imaging