Screening for obstructive sleep apnea in veterans with ischemic heart disease using a computer-based clinical decision-support system

Objectives: To assess the validity of a handheld clinical decision-support system (CDSS) in detecting obstructive sleep apnea (OSA) in veterans with ischemic heart disease against polysomnography (PSG) and to compare the diagnostic accuracy of the CDSS versus the Berlin questionnaire. Methods: We enrolled prospectively 143 patients with underlying ischemic heart disease. Veterans with history of neurologic disease, systolic congestive heart failure, or receiving opiates were excluded from participation. Participants were asked to complete the Berlin Questionnaire and to answer all eight questions of CDSS-software. At the end of the interview, veterans were scheduled for an in-laboratory polysomnogram. Results: Ninety one patients completed the study. The prevalence of OSA (AHI ≥5/h) was 74.7 % with a median AHI of 11.5/h (range 0-90). When compared to PSG, the CDSS and the Berlin questionnaire achieved a sensitivity of 98.5 % [95 % confidence interval (CI) 92.1-100] and 80.9 % (95 % CI 69.5-89.4) and a specificity of 86.9 % (95 % CI 66.4-97.2) and 39.1 % (95 % CI 19.7-61.5) at a threshold value of AHI ≥5 with a corresponding area under the curve of 0.93 (95 % CI 0.85-0.97) and 0.60 (95 % CI 0.49-0.70); respectively. Conclusions: CDSS is a superior screening tool for identifying cardiac veterans with undiagnosed OSA than the BQ.