Cardiovascular Load During Obstructive Sleep Apneas In Comparison To Physical Load

Aim of this study was to assess cardiovascular load during obstructive apnea in nREM- and REM-sleep in comparison with standardized bicycle exercise. We investigated 16 male patients with severe sleep apnea (mean RDI 66.3) and arterial hypertension (mean bp 161/105 mmHg) using standardized polysomnography and intraarterial blood pressure monitoring (10 obstructive apneas during nREM- and REM-sleep, n = 2 * 160). Mean arterial blood pressure and heart rate were 93.0 mmHg and 66.3 min(-1) during nREM-sleep, 102 mmHg and 65.7 min(-1) during REM-sleep. Increases of mean blood pressure and heart rate were 45.6 mmHg and 25,8 min(-1) during nREM-sleep and 53.3 mmHg and 31.9 min(-1) during REM-sleep. During bicycle exercise mean blood pressure and heart rate rises 16.2 mmHg and 17.9 min(-1) during 50 Watt, 21.1 mmHg and 23.9 min(-1) during 75 Watt and 26.7 mmHg and 29.2 min(-1) during 100 Watt. During obstructive apneas cardiovascular load is highly increased. Diastolic blood pressure elevations may be caused by increased peripheral resistance during sleep apnea.