The relationship between the severity of sleep apnea syndrome and 24-h blood pressure values in patients with obstructive sleep apnea.

Automated ambulatory 24-h BP monitoring was made in 38 patients with obstructive sleep apnea syndrome. Stepwise multiple regression analysis revealed that diastolic, systolic, and mean BP values during sleep as well as during wakefulness were significantly related to apnea/hypopnea index and age. Minimal arterial O2 saturation and total sleep time also significantly contributed to diastolic and mean BP values during sleep. Body mass index did not significantly contribute to any of the BP values. These results support a causal relationship between the severity of sleep apnea syndrome and systemic hypertension.