Clinical Utility of Berlin Questionnaire in Comparison to Polysomnography in Patients with Obstructive Sleep Apnea

The aim of this study was to assess the utility of the Berlin questionnaire (BQ) in adult patients at high risk of obstructive sleep apnea (OSA). The study consisted of 64 patients recruited for the polysomnography diagnostics of sleep respiratory disturbances. The anthropometric assessment included body weight, height, and body mass index (BMI), all related to the risk of OSA. The BQ consisted of the following three categories: 1 - snoring, 2 - daytime somnolence, and 3 - hypertension. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were evaluated. Likelihood ratio was used to assess the diagnostic accuracy. We found that patients were, on average obese; the mean BMI amounted to 31.9 +/- 6.0 kg/m(2). Polysomnography identified OSA in 73.4% of patients (AHI > 5), where the BQ categorized 87.5% of patients at high risk of OSA. Sensitivity of the BQ was 87.2%, specificity 11.8%, PPV 73.2%, and NPV 25.0%. Diagnostic accuracy assessed by the likelihood ratio had a value of 1.00. The BQ had a false discovery rate of 31.2% and misclassification rate of 32.8%. We conclude that the BQ is a sensitive tool that should be used in clinical settings in which the benefit of high sensitivity outweighs the disadvantage of low specificity.