Sleep apnea physiological burdens and markers of white matter injury: the Multi-Ethnic Study of Atherosclerosis

Obstructive sleep apnea (OSA) is associated with cognitive impairment; however, the underlying mechanisms remain incompletely understood. OSA is characterized by periods of interrupted ventilation ("ventilatory burden (VB)"), leading to hypoxemia ("hypoxic burden (HB)") and/or arousal ("arousal burden (AB)") from sleep. While hypoxemia is considered a key mechanism underlying white matter injury, its measurement has been limited. In our primary analysis, we assessed the association of HB, a quantitative measure of hypoxemia, with white matter hyperintensity volume (WMH