Differences in arousal response between aged and middle-aged patients with obstructive sleep apnea syndrome.

The aim of this study is to show the clinical significance of the differences in arousal response at a termination of apnea/hypopnea between aged and middle-aged patients with obstructive sleep apnea syndrome (OSAS). We polygraphically assessed electrocardiographic (ECG) and electroencephalographic (EEG) arousal. Electrocardiographic arousal was defined as an abrupt increase in heart rate at a termination of apnea/hypopnea. Our findings showed that EEG and ECG arousal at a termination of apnea/hypopnea were significantly suppressed in aged patients with OSAS, which might provide useful information on the pathophysiology, of OSAS.