Purpose: The aim of this study was to compare the sensitivity and specificity of two questionnaires to identify patients with obstructive sleep apnea (OSA).
Materials and methods: Fifty-three moderate to severe OSA patients [with a respiratory disturbance index (RDI) ≥ 15] and 31 controls (RDI < 15) based on ambulatory somnographic assessment were recruited through flyers and mail at USC School of Dentistry. Each patient answered the Berlin and apnea risk evaluation system (ARES) questionnaires. The responses to the questionnaires were scored and compared for significant group differences.
Results: Moderate and severe OSA patients were predominantly male, older, had a larger neck size, and larger body mass index than controls. There were no significant differences in race or ethnicity between the two groups. In this study, subjects having a "high risk" ARES questionnaire were 7.9 times as likely to have OSA as subjects with "low or no risk" score (p = 0.0002). The ARES questionnaire had a sensitivity of 90.6%, specificity of 43.2%, a positive predictive value (PPV) of 73.8%, and negative predictive value (NPV) of 73.7% compared to 67.9%, 54.8%, 72%, and 50%, respectively, for the Berlin questionnaire using a cut point of RDI ≥ 15.
Conclusions: In this specific patient group, not uncommon to the regular dental private practice, the ARES questionnaire performed better than the Berlin questionnaire with higher sensitivity, similar PPV, higher NPV, but lower specificity. The lower specificity could be explained in part because the ARES has been tailored to screen patients with an RDI ≥ 5, and our study included mostly mild to severe patients. In conclusion, in this specific group of subjects, the ARES questionnaire is a better choice than the Berlin questionnaire; however, the Berlin questionnaire is publicly available and the ARES screener is proprietary.