title: Hypercapnic obstructive sleep apnea: an underappreciated marker of severity.
authors: Clifford
authors: C
authors: Zwillich
authors: Carolyn H
authors: CH
authors: Welsh
mesh_terms: D006801:Humans; D006935:Hypercapnia / Q000503:physiopathology*; D009765:Obesity / Q000503:physiopathology; D012720:Severity of Illness Index; D020181:Sleep Apnea, Obstructive / Q000503:physiopathology*