Evaluation of Berlin Questionnaire Validity for Sleep Apnea Risk in Sleep Clinic Populations

Introduction: The Berlin questionnaire (BQ) is a common tool to screen for Obstructive Sleep Apnea (OSA) in the general population, but its application in the clinical sleep setting is still challenging. The aim of this study was to determine the specificity and sensitivity of the BQ compared to the apnea-hypopnea index obtained from polysomnography recordings obtained from a sleep clinic in Iran. Methods: We recruited 100 patients who were referred to the Sleep Disorders Research Center of Kermanshah University of Medical Sciences for the evaluation of suspected sleep-disorder breathing difficulties. Patients completed a Persian version of BQ and underwent one night of PSG. For each patient, Apnea-Hypopnea Index (AHI) was calculated to assess the diagnosis and severity of OSA. Severity of OSA was categorized as mild when AHI was between 5 and 15, moderate when it was between 15 and 30, and severe when it was more than 30. Results: BQ results categorized 65% of our patients as high risk and 35% as low risk for OSA. The sensitivity and the specificity of BQ for OSA diagnosis with AHI>5 were 77.3% and 23.1%, respectively. Positive predictive value was 68.0% and negative predictive value was 22.0%. Moreover, the area under curve was 0.53 (95% CI: 0.49 – 0.67, P=0.38). Discussion: Our findings suggested that BQ, despite its advantages in the general population, is not a precise tool to determine the risk of sleep apnea in the clinical setting, particularly in the sleep clinic population.