[Evaluation of Watch PAT as a diagnosing test for patients with obstructive sleep apnea hypopnea syndrome].

OBJECTIVE: This study aimed to test the accuracy of the watch peripheral arterial tone (Watch PAT) in diagnosing the obstructive sleep apnea hypopnea syndrome (OSAHS) and its influencing factors.

METHODS: Thirty five outpatients who had a chief complaining of sleep snoring were recruited to receive Watch PAT test and polysomnography (PSG) simultaneously. The results of PSG were manually analyzed by an experienced technician, while the results of Watch PAT were automatically analyzed by software.

RESULTS: There was a trend that the apnea hypopnea index (AHI) of PSG was significantly higher than that of Watch PAT (P = 0.06) in the 35 patients studied, however, these two variables were significantly correlated (P < 0.001), and the correlation coefficient was as high as 0.955. A linear regression analysis which used the AHI of Watch PAT to predict the AHI of PSG also concluded same result and the equation was AHI (PSG) = 0.944 + 1.030AHI (Watch PAT), P < 0.001. The analysis which used ROC curve to test the diagnostic efficiency of Watch PAT concluded that the area under the curve could reach to 0.953 (P < 0.001), and if an AHI (Watch PAT) threshold of ≥ 8.65 was used as the cut-off point in this study, the sensitivity and specificity could reach to 92.3% and 100.0%. The absolute values of the differences (AVD) between the AHI of Watch PAT and the AHI of PSG were also calculated as a criterion for grouping the 35 patients studied, then it could be found that there was a trend that the BMI of patients who had an AVD ≥ 5 were higher than that of patients who had an AVD < 5 (P = 0.077).

CONCLUSIONS: The Watch PAT is highly sensitive in the diagnosis of OSAHS, it can be used as a simple and reliable method for screening people with suspicious OSAHS. However, the accuracy of diagnosis may be relatively low in patients who have a great BMI.