Study objectives: To identify a link between sleep disordered breathing, nocturnal hypoxemia, and lung cancer. Methods: We conducted a cross-sectional study of a combined cohort of 302 individuals derived from the sleep apnea in lung cancer study (SAIL; NCT02764866) investigating the prevalence of sleep apnea in lung cancer, and the sleep apnea in lung cancer screening study (SAILS; NCT02764866) investigating the prevalence of sleep apnea in a lung cancer screening program. All subjects had spirometry and a chest CT, underwent home sleep apnea testing (HSAT), and completed a sleep related questionnaire. Subjects from the SAIL study underwent HSAT prior to initiating oncologic therapy or surgery. Subjects with an apnea-hypopnea index (AHI) > 15 were compared with a control group of individuals with an AHI < 15. Propensity score, near neighbor matching, and logistic regression adjusted for potential confounders, were used in order to evaluate the association between sleep apnea, the AHI, oxygen desaturation indices and lung cancer. Results: The prevalence of sleep apnea and lung cancer in the combined cohort was 42% and 21%, respectively. Lung cancer was 8% more prevalent in patients with an AHI >15. The difference was statistically significant when assessed by propensity score matching (p = 0.015) and nearest neighbor matching (p = 0.041). Binary logistic regression adjusted for potential confounders revealed a statistically significant association between AHI (p = 0.04), nocturnal hypoxemia, including time spent below 90% oxyhemoglobin saturation (T90%; p = 0.005), 3% oxygen desaturation index (ODI3; p = 0.02) and lung cancer. Conclusions: Sleep apnea and nocturnal hypoxemia are associated with an increased prevalence of lung cancer. (C) 2019 Elsevier B.V. All rights reserved.