STUDY OBJECTIVES: To determine whether adherence to continuous positive airway pressure (CPAP) in adults with uncomplicated obstructive sleep apnea differs by rural vs urban residential address. METHODS: In this prospective cohort study, we recruited adults who initiated CPAP for uncomplicated obstructive sleep apnea that was diagnosed by a physician using sleep specialist-interpreted diagnostic testing. Participants were classified as urban (community size > 100,000) or rural (community size < 100,000) by translating residential postal code into geographic census area. The primary outcome was mean daily hours of CPAP use compared between rural and urban patients. Secondary outcomes included the proportion of patients who were adherent to CPAP, change in Epworth Sleepiness Scale score, change in EuroQOL-5D visual analog score, and Visit-Specific Satisfaction Instrument score. All outcomes were measured 3 months after CPAP initiation. RESULTS: We enrolled 242 patients (100 rural) with a mean (standard deviation) age of 51 (13) years and a respiratory event index of 24 (18) events/h. The mean (95% confidence interval) CPAP use was 3.19 (2.8-3.58) hours/night and 35% were CPAP-adherent, with no difference between urban and rural patients. Among the 65% of patients who were using CPAP at 3 months, the mean CPAP use was 4.89 (4.51-5.28) hours/night and was not different between rural and urban patients. Improvement in the Epworth Sleepiness Scale score and patient satisfaction was similar between groups, but the EuroQOL-5D score improved to a greater extent in rural patients. Urban or rural residence was not associated with CPAP adherence according to multivariable regression analysis. CONCLUSIONS: Rural vs urban residence was not associated with differences in CPAP adherence among patients with uncomplicated OSA diagnosed by a physician using specialist-interpreted sleep diagnostic testing. CITATION: Corrigan J, Tsai WH, Ip-Buting A, et al. Treatment outcomes among rural and urban patients with obstructive sleep apnea: a prospective cohort study. J Clin Sleep Med. 2022;18(4):1013-1020.