Relationship between sleep apnea hypopnea syndrome and cardiovascular events in elderly Chinese snorers

Objective To investigate the relationship between sleep apnea hypopnea syndrome (SAHS) and some cardiovascular abnormalities in elderly snorers, as well as the effectiveness of nasal continuous positive airway pressure on those with SAHS.Methods With the use of polysomnography, 73 elderly snorers (older than 60 years) were examined and placed into either the SAHS group or the control group. Using ambulatory electrocardiogram (ECG) and blood pressure measurement, daily nocturnal rhythm of blood pressure, hypertension, heart rate variability, some arrhythmia and angina pectoris of coronary heart disease (CHD) were monitored and compared between the two groups before and after 5-7 days of treatment with nasal continuous positive airway pressure on the SAHS group. Results This study indicated a higher incidence (47.9%) of sleep apnea syndrome in elderly snorers and demonstrated that there was a significantly higher incidence of hypertension, disappearance in daily nocturnal rhythm of blood pressure, poor effectiveness of nitrate on angina pectoris of coronary heart disease, decreased heart rate variability during sleep, increased arrhythmia and lower pulse oxygen saturation (SpO(2)) levels in the SAHS group than in the control group. After nasal continuous positive airway pressure treatment during sleep, snoring control, significantly higher SpO(2) levels and lower index of apnea/hypopnea were achieved in the SAHS group; heart rate variability (HRV) and blood pressure day nocturnal rhythm were returned to normal levels.Conclusion This research suggests that there is a close relationship between the development of sleep apnea syndrome and some cardiovascular diseases. Continuous positive nasal airway pressure is effective not only on SAHS but also on coexisting cardiovascular disorders.