Use of the pictorial Sleepiness and Sleep Apnoea Scale in Chinese patients with suspected obstructive sleep apnoea syndrome

BACKGROUND: Sleep related breathing disorders represent a significant health burden. Being able to stratify patients according to their need for differing types of investigation and predicting the likelihood of obstructive sleep apnoea syndrome (OSAS) is helpful. This study attempts to assess the value of a pictorial Sleepiness and Sleep Apnoea Scale (pSSAS) in this process. METHODS: A total of 126 sequential patients attending a sleep service with suspected OSAS completed the pSSAS, the Epworth Sleepiness Score (ESS), and the Berlin Questionnaire (BQ) prior to full polysomnography. RESULTS: With Apnoea-hypopnea index (AHI) >15 as the positive diagnostic criterion, the area under the receiver operating characteristic curve (AUC) of the BQ was the highest (0.683), followed by pSSAS and ESS (AUC 0.648 and 0.516, respectively). With AHI >30 as the positive diagnostic criterion, the AUC of pSSAS was the highest (0.696), followed by BQ and ESS (AUC 0.653 and 0.510, respectively). With MiniSO(2) <80% as the positive diagnostic criterion, the AUC of pSSAS was the highest (0.736), followed by BQ and ESS (AUC 0.634 and 0.516, respectively). CONCLUSIONS: This study shows that the pSSAS which was first tested in a European population performs equally well amongst a Chinese population. The pSSAS performed in a similar fashion to the BQ in predicting those likely to have OSAS and was superior at predicting those who have severe OSAS. Because it is a pictorial questionnaire, it has advantages for those who may have reduced health literacy, a problem which is under-recognized in most healthcare systems.