Project 458547

The low levels of oxygen for the human body is called hypoxia. Hypoxia negatively impacts the human body and impairs normal functions. Long-term exposure to hypoxia can lead to disease conditions, and severe forms of exposure can lead to death. Hypoxia can occur in many forms and settings, such as obstructive sleep apnea (OSA), high altitude exposure, critical illnesses (intensive care setting) as well as stroke, heart attack, and Coronavirus Disease 2019. The short bouts of hypoxia due to the collapse of the upper airway during sleep in OSA is called intermittent hypoxia (IH). The IH from OSA is associated with a number of adverse health consequences such as high blood pressure, stroke, heart attack. Similarly, a large number of the population is exposed to high altitude hypoxia by permanently living at altitude, professionally, and as a part of recreation such as hiking, skiing, climbing. Both short-term exposure to high altitude and long-term stay at high altitude (subacute and chronic exposure) negatively impact the health and performance of humans. Therefore, I would like to investigate the effects of hypoxia (IH and high altitude hypoxia) on neurocognitive functions, sleep microstructures (spindles and K-complexes), and breathing mechanisms (ventilatory controls). The study will utilize home sleep recordings (polysomnography), extensive neurocognitive tests, and computer-controlled physiological testings to quantify breathing (ventilatory) responses. The first study will explore the effect of continuous airway pressure and oxygen supplementation on heart and lung functions among OSA patients. The second study will investigate cognitive functions and sleep microstructures among older adult OSA patients using home sleep recordings and extensive cognitive tests. The third study will study sleep microstructure and cognitive functions among high-altitude workers from an astronomical observatory located at the Atacama desert (5050m), Chile.