Daytime Hypercapnia in Adult Patients With Obstructive Sleep Apnea Syndrome in France, Before Initiating Nocturnal Nasal Continuous Positive Airway Pressure Therapy

Daytime hypercapnia was observed in > 1 of 10 patients with OSAS needing CPAP therapy and free of COPD, and was related to the severity of obesity and obesity-related impairment in lung function. However, other mechanisms than obesity are probably involved in the pathogenesis of daytime hypercapnia in OSAS