Recovery of Heart Rate Variability in Patients with Moderate to Severe Obstructive Sleep Apnea after 6-Month Continuous Positive Airway Pressure Treatment
Pimporn Limphanudom MD*, Nitipatana Chierakul MD*, Narongsak Pinyopattarakul MD*, Arth Nana MD*, Chana Naruman*, Suwat Tangchityongsiva*, Wattana B Wattanapa MD**, Anorut Jenwitheesak**
Affiliation : * Division of Respiratory Disease and Tuberculosis, Department of Medicine, ** Department of Physiology, Faculty of Medicine Siriraj Hospital, Mahidol University
Objective : To evaluate the effect of long-term treatment with continuous positive airway pressure (CPAP) on
the heart rate variability (HRV) of obstructive sleep apnea (OSA) patients.
Materials and Methods : Patients with moderate to severe OSA who had never used CPAP treatment were
enrolled. Short recording HRV analysis was performed at baseline then at one, three, and six months after
CPAP treatment. The measurement included low frequency HRV (LF), high frequency HRV (HF), low frequency
to high frequency ratio (LHR), and standard deviation of R-R intervals (SDNN). All domains were measured
both during spontaneous and deep breathing.
Results : There were 10 patients in the present study, all were men with the mean age of 45 years, mean body
mass index 29.3 kg/m2, mean apnea-hypopnea index 60.9 events/hour, and mean average CPAP usage 4.8
hours/night. The HRV showed no significant change after one and three months of CPAP treatment. At 6
months, the only significant change was the SDNN measured after deep breathing (28.80 + 9.83 vs. 34.43 +
14.23 millisecond, p = 0.032).
Conclusion : One aspect of heart rate variability in moderate to severe obstructive sleep apnea patients was
improved after six month’s continuous positive airway pressure treatment.
Keywords : Obstructive sleep apnea, Continuous positive airway pressure, Heart rate variability
