Modified Mallampati Score Improves Specificity of STOP-BANG Questionnaire for Obstructive Sleep Apnea

Background: An accurate, clinical screening tool for obstructive sleep apnea (OSA) that identifies patients for further diagnostic testing would assist in the diagnosis of this comorbidity. One example, the STOP-BANG questionnaire (SBQ), has been validated as a screening tool with high sensitivity. However, its specificity may result in a high false-positive rate. The aim of this study to determine if addition of the Modified Mallampati score to the SBQ improves its specificity. Methods: The authors studied 162 patients referred to the Sleep Disorders Clinic at Yedikule Chest Disease Education and Research Hospital. All patients were prospectively screened for risk of OSA using the SBQ, their oral anatomy was assessed by Modified Mallampati scoring, and sleep quality characterized by polysomnography. Polysomnography results were reviewed when available and the predictive performance of the SBQ and the modified SBQ scoring models were compared. Results: In the authors' study an SBQ score >= 3 yielded sensitivities of 0.85, 0.86, and 0.91 for Apnea-Hypopnea Index (AHI) >= 5/h, AHI >= 15/h, and AHI >= 30/h, respectively, and specificities of 0.09, 0.10, and 0.18. The modified SBQ with a cutoff of >= 4 (>3) points for AHI levels of >5, >15, and >30 yielded respective sensitivities of 0.84, 0.86, and 0.91 and specificities of 0.25, 0.26, and 0.27. Conclusions: The author's results from indicated the modified SBQ with a cutoff of >= 4 (>3) points in this study was more specific than the standard SBQ but no less sensitive, and may be used in identifying OSA patients for further diagnostic evaluation or avoiding unnecessary testing.