Effect of CPAP on Abnormal Gastroesophageal Reflux and Lung Inflammation in IPF

Inclusion Criteria: * confirmed diagnosis of IPF based on the 2018 IPF guidelines * high likelihood of OSA based on the STOP-BANG measure, with a score of 3 or greater * patients on nintedanib, or in whom nintedanib will be initiated prior to enrollment in the study * able to participated in 24hr pH monitoring * able to comply with CPAP treatment * able to provide written informed consent prior to any study procedures * willing to complete all study measurements and assessments in compliance with the protocol Exclusion Criteria: * interstitial lung disease caused by conditions other than IPF * severe concomitant illness limiting life expectancy (\< 1 year) * residual lung volume \> or equal to 120% of predicted * obstructive lung disease: FEV1/FVC ratio \< 0.70 * current drug or alcohol dependence * patients who are unable to tolerate nintedanib * patients who are unable to use CPAP or are unwilling to participate in the 24 hr pH probe placement * patients who were diagnosed with recent IPF exacerbation within 4 weeks of enrollment (may be rescheduled for enrollment once recovered) * patients who have had prior nasal surgery or trauma that would make pH probe placement difficult * patients on anticoagulation (aspirin is not an exclusion)