The Study Of Heart Rate Variability In Patients With Obstructive Sleep Apnea Syndrome And Screening Of Obstructive Sleep Apnea Syndrome By Heart Rate Variability Analysis

Objective: The study was to investigate daytime and nighttime variation of heart rate variability (HRV) in patients with obstructive sleep apnea syndrome(OSAS) and evaluate the screening capacity of HRV . Methods : We have selected 80 subjects , made a measurement of such parameters as BMI and blood pressure, and investigated their histories of diabetes and hypertension. The patients for suspected sleep apnea underwent 7-hour nocturnal polysomnography (PSG) recording with standard methods in sleep lab. The presence and stages of sleep were monitored by use of 2 pairs of EEG leads, 2 pairs of electro-oculographic leads, and chin lectromyographic leads. Air flow was measured by an oronasal thermocoupler. Respiratory efforts were monitored by use of respiratory plethysmography with transducers placed around the chest and abdomen. Arterial oxygen saturation was continuously recorded by pulse oximetry during the entire night. All subjects underwent Ambulatory electro-cardiography(Holter) monitoring. The time-domain analysis parameters , such as day SDNN, night SDNN, A [D/N]SDNN, day RMSSD, night RMSSD, A [D/N] RMSSD, day PNN5o, night PNN5o, A [D/N]PNN50, and the frequency-analysis parameters, such as day ULF,night ULF, A [D/N]ULF, day VLF, night VLF, A [D/N]VLF, day LF, night LF, A [D/N]LF, day HF, night HF, A [D/N]HF, were measured. 50 patients monitored by PSG are diagnosed OSAS+ and OSAS- by analysis of PSG and HRV. According to the gold standard of PSG, we evaluate the screening capacity of HRV to patients with OSAS. Results: The time-domain analysis parameters, Mean night SDNN, A [D/N] SDNN, mean night RMSSD, A [D/N]RMSSD, mean night PNN50) A [D/N]PNN50 , and the frequency-analysis parameters mean night ULF, mean night VLF, A [D/N] VLF, mean night LF, A [D/N]LF, mean night HF, A [D/N]HF were significantly higher in OSAS+ patients, the threshold value of -11 for A[D/N]SDNN determined a sensitivity of 70% and a specificity of 50%, and the threshold value of -13 for A [D/N] RMSSD determined a sensitivity of 70% and a specificity of 60%. The total evaluation of A [D/N]SDNN, A [D/N]RMSSD, A[D/N]PNN50 and mean heart >1 determined a sensitivity of 75% and a specificity of 70%, >2 determined a sensitivity of 70% and a specificity of 80%, >3 determined a sensitivity of 37. 5% and a specificity of 90%.