Obstructive sleep apnea: Impact of hypoxemia on memory

Purpose Attempts to understand the causes of cognitive impairment in obstructive sleep apnea (OSA) are complicated by the overlap among clinical and demographic factors that may impact cognition. The goal of the current study was to isolate the contribution of hypoxemia to cognitive impairment in OSA. Methods Two groups of 20 patients with newly diagnosed OSA were compared. The groups differed on severity of hypoxemia but not other demographic (e.g., age, gender, education, estimated premorbid IQ) or clinical (e.g., sleep related respiratory disturbances, daytime sleepiness, depressive symptoms) variables. Participants completed polysonmography and cognitive assessment. Results We compared patients with high and low hypoxemia on measures of memory, attention, executive functioning, and motor coordination using independent sample t -tests. The high hypoxemia group performed significantly better on immediate recall (Hopkins Verbal Learning Test — Revised; t = −2.50, p