Kitajima T, et al. - The clinical significance of episodic nocturnal hypercapnia (eNH), as well as the efficacy of eNH-targeted noninvasive positive pressure ventilation (NPPV) in patients with stable advanced COPD, was determined herein. Findings suggested eNH may offer risk for exacerbations, hypoalbuminemia, and pulmonary hypertension in patients with stable severe or very severe COPD, and NPPV may be effective against hypoalbuminemia and acute exacerbations.