[Diagnosis of obstructive sleep apnea using cardiopulmonary coupling analysis]

Objective: To explore the diagnostic value of cardiopulmonary coupling analysis in the screening of obstructive sleep apnea (OSA). Methods: A total of 44 participants with sleep disorders from Sleep Medicine Center of West China Hospital in May 2016 were included in the study. All participants were monitored with cardiopulmonary coupling while undergoing polysomnography (PSG). The sleep parameters detected by cardiopulmonary coupling and PSG were compared and the correlation between respiratory disturbance index (RDI) of cardiopulmonary coupling and sleep parameters of PSG were analyzed. Using PSG as "golden standard" , the sensitivity, specificity, positive predictive value, negative predictive value and the corresponding areas under the receiver operating characteristic (ROC) curves were calculated for cardiopulmonary coupling. Results: There were 44 participants included in the study (37 males and 7 females) with a mean age of (46.3±12.5) years old and a mean body mass index of (25.6±3.7) kg/m(2). And there were 33 subjects diagnosed with OSA. There were no significant difference between respiratory disturbance index (RDI) derived from cardiopulmonary coupling and apnea-hypopnea index (AHI) derived from PSG. Correlation analysis showed that the RDI, low frequency coupling monitored by cardiopulmonary coupling was positively correlated with AHI detected by PSG (r=0.849, 0.850, both P<0.001); and the high frequency coupling was significantly negatively correlated with AHI (r=-0.767, P<0.001). For AHI ≥5/h, ≥10/h, ≥15/h, ≥20/h and ≥30/h respectively according to PSG, sensitivity was 0.82, 0.93, 0.96, 0.96, 0.77, specificity was 0.50, 0.75 0.72, 0.80, 0.86, positive predictive value was 0.85, 0.87, 0.83, 0.85, 0.85, negative predictive value was 0.55, 0.86, 0.93, 0.94, 0.79 for cardiopulmonary coupling. The corresponding areas under the ROC curves were 0.868, 0.892, 0.915, 0.942, 0.921 respectively. In addition, when the RDI derived from CPC was higher than 20.4/h, the patients were more likely suffering from OSA, and the sensitivity was 0.79 and the specificity was 0.91. Conclusions: The results of cardiopulmonary coupling are consistent with simultaneous PSG parameters. Cardiopulmonary coupling has a highly diagnostic value for sleep respiratory disorder.