[Application of three questionnaires in screening obstructive sleep apnea in patients with chronic obstructive...

Objective: To evaluate the clinical value of three questionnaires [Sleep Apnea Clinical Score (SACS), Berlin Questionnaire (BQ), and Epworth Sleepiness Scale (ESS)] in screening obstructive sleep apnea (OSA) in patients with chronic obstructive pulmonary disease (COPD). Methods: A total of 198 patients with COPD were assessed the likelihood of OSA by using the SACS, BQ, ESS, which was confirmed by the overnight polysomnography (PSG). The receiver operating characteristic curve (ROC) and the calculated likelihood ratios were used to compare the values of three scoring systems in predicting OSA in COPD patients. Results: The patients had an average age of (65.5±9.3) years and 92.9% (184 cases) of which were male, 14 cases (7.1%) were female; 27 cases (13.6%) had a high probability of OSA by SACS assessment, 61 cases (30.8%) had a high probability screened by BQ, and 72 (36.4%) had OSA high probability by ESS. The diagnosis of OSA in 75 patients (37.9%) were confirmed by PSG. OSA did not be accurately predicted by ESS screening in patients with COPD, with a ROC curve area under the curve of 0.592 (95% CI: 0.509-0.674, P=0.053). BQ had an area under the ROC curve of 0.706 (95% CI: 0.626-0.779, P<0.001). However, the prediction of SACS was much better, with an area under the ROC curve of 0.810 (95% CI: 0.737-0.871, P<0.001). Conclusion: SACS is superior to BQ and ESS in predicting OSA in this group of patients with COPD.