CPAP Randomized Controlled Trial

The overall goal of this randomized controlled trial is to test the hypothesis that in older adults with mild cognitive impairment (MCI) and previously untreated obstructive sleep apnea (OSA), 4 months of web-based sleep education and continuous positive airway pressure (CPAP) will improve cognitive function more than web-based sleep education alone. Secondarily, this trial will test the hypothesis that 8 months of CPAP will improve cognitive function more than 4 months of CPAP. Moreover, treating OSA with CPAP can improve cognitive function and reduce Alzheimer's disease-related brain changes in older adults with MCI. This study will compare an Early CPAP Group who will receive CPAP and sleep education simultaneously for 8 months upon enrollment to a Later CPAP Group who will first receive sleep education for 4 months followed by CPAP and sleep education for the next 4 months to test if early treatment is more beneficial. Participants will: 1. Complete web-based sleep education modules through the Brain Health Pro (BHP) platform 2. Undergo CPAP therapy, including in-person mask fitting and regular monitoring alongside a study sleep technologist At 0 months, 4 months, and 8 months, participants will participate in cognitive assessments, provide blood samples, use wearable devices to measure sleep patterns and physiology, and complete a 1-hr MRI (0 months and 4 months only).