P442 The predicting value of nocturia in obstructive sleep apnea syndrome

Abstract

Objectives: To compare sleep heart rate (SHR) and heart rate (HR) tachogram patterns among patients with obstructive sleep apnea (OSA). Design: Retrospective study in academic teaching hospital. Methods and Measurements: Subjects (Male 18, Female 2; Age 58.1 ± 12.5 years; ODI4 21.2 ± 12.1/h) were OPD patients with proven OSA by nocturnal sleep study (WinVisi sleep study). SHR, HR tachogram and HRV data were taken from 24 hr Holter monitoring study before treatment of CPAP. Result: Sleep heart rate was well correlated with HRV parameters; SDNN 0.681, SDANN 0.654, Mean NN 0.659. But correlation with severity parameter of OSA was not good; ODI4 0.309. Twenty patients could be divided by the pattern of HR tachogram: unimodal pattern and non-unimodal pattern. In patients with unimodal HR tachogram (n = 10), SHR was higher (80.0 ± 20.9/min vs 63.3 ± 7.9/min, P = 0.036) and SDNN was lower (72.6 ± 22.7 ms vs 128.9 ± 34.0 ms, P = 0.0005) than in patients with non-unimodal pattern (n = 10). No difference of ODI4 was found in these two groups; 21.7 ± 14.9/h vs 20.5 ± 9.2/h, P = 0.825. Conclusion: SHR and HR tachogram pattern were important in distinguishing two different subgroups of OSA(unimodal pattern and non-unimodal pattern). SHR was well correlated with HRV parameters. In contrary, SHR did not show good correlation with severity parameter of OSA (ODI4).