https://www.selleckchem.com/products/phenazine-methosulfate.html 1 mmHg, = 0.030). PaCO higher than 59 mmHg after HFNC for 24 h was identified as an independent risk factor for treatment failure [OR 1.078, 95% CI 1.006-1.154, = 0.032]. In AECOPD patients with acute compensated hypercapnic respiratory failure, HFNC improved the prognosis compared with COT. Therefore, HFNC might be considered for first-line oxygen therapy in select patients. ClinicalTrials.Gov NCT02439333. ClinicalTrials.Gov NCT02439333. To identify associated factors of having at least one of the airflow limitation, chronic cough/phlegm, and currently treated respiratory diseases in health examinees, and to describe the characteristics of each subgroup classified by comorbidities. This was an observational cross-sectional survey carried out in multiple regions of Japan. Subjects aged 40 years older, undergoing comprehensive health examination, were recruited. Airflow limitation was defined as having forced expiratory volume in 1 s/forced vital capacity lower than 70%. Associated factors of having at least one of the airflow limitation, chronic cough/phlegm, and currently treated respiratory diseases were examined by logistic regression analysis. Subgroup classification by comorbidity patterns was conducted by hierarchical cluster analysis. In a total of 22,293 subjects, 1520 (6.8%) had at least one of the airflow limitation, chronic cough/phlegm, and currently treated respiratory diseases. With this objective variable, the following exver-smokers. Different comorbidity patterns were observed by smoking history. These findings could provide information to assist the management of subjects with COPD or at risk for COPD in the general population. Several factors were identified as associated factors of having at least one of airflow limitation, chronic cough/phlegm, and currently treated respiratory diseases and they were different between ever-smokers and never-smokers. Different comorbidity patterns w