Assessment of Continuous Positive Airway Pressure Therapy in OSA and ILD

This study is comprised of 3 aims: Aim 1: Determine whether the greater OSA severity is associated with higher levels of serum biomarkers of AEC and endothelial injury and ECM remodeling in community-dwelling adults. This is a retrospective study that will analyze biospecimens from those who participated in the MESA sleep study \[Chen et al\]. Aim 2: Determine whether CPAP use is associated with reductions in alveolar epithelial cell (AEC) injury and endothelial injury, and extracellular matrix (ECM) remodeling biomarkers in adults with moderate-to-severe OSA. This is a retrospective study that will analyze biospecimens from those who participated in either the HeartBEAT \[Gottlieb et al\] and BestAIR \[Bakker et al\] studies. Revised Aim 3: a) Determine whether untreated OSA promotes AEC and endothelial injury and ECM remodeling biomarkers in adults with ILD and OSA compared with those without OSA; b) Determine prospectively whether clinically-initiated 4-week PAP therapy increases markers of alveolar endothelial lung injury in OSA. Participants will be recruited at Columbia University and be assigned CPAP therapy as an intervention.