Objective: Obstructive sleep apnea (OSA) is a significant comorbidity in patients with idiopathic pulmonary fibrosis (IPF). This study aimed to evaluate the demographic and clinical characteristics of patients with and without IPF, and their polysomnographic features according to the presence and severity of OSA. 
 Methods: A total of 52 cases (29 patients hospitalized for IPF and 23 controls without IPF) admitted to the sleep laboratory with suspicion of OSA were included. Demographic, clinical data and results of polysomnographic studies were recorded from the patients’ self-reports and hospital records.
 Results: The distribution of sex was similar (p=0.775) between the patient and control groups; however, the patients with IPF were older than the controls (68 vs. 57 years, p=0.003). The rate of current smokers was higher among the controls (p=0.003), whereas dyspnea (p