Obstructive sleep apnea (OSA) is closely linked to poor outcomes in chronic obstructive pulmonary disease (COPD) patients, reveals the latest research. A new study conducted by Dr Pan Zhang and team from the Department of Respiratory Medicine, Affiliated with Hospital of Xuzhou Medical University, China, found that  a combination of  obstructive sleep apnea and COPD, called ‘overlap syndrome’ is strongly associated with poor outcomes in COPD patients. At the same time, the researchers also said that their findings indicate the risk of OSA was lower in patients with severe COPD, compared with mild or moderate COPD. The study results, published in BMC Pulmonary Medicine, the report pointed out that patients with overlap syndrome had a poorer quality of life, more daytime sleepiness, and a higher prevalence of hypertension and diabetes than patients with COPD alone. The researchers said that they had also importantly found that BMI, neck circumference, ESS, CAT, CCI, HADS, hypertension, and diabetes were independent risk factors for OSA in patients with COPD.