DOUBLE PRODUCT CAN BE REDUCED BY CPAP IN SLEEP APNEA SYNDROME PATIENTS

Abstract

Objective: Sleep apnea syndrome (SAS) is associated with increased cardiovascular mortality mediated by intermittent hypoxia, oxidative stress, endothelial dysfunction, and sympathetic nerve activation. Continuous positive airway pressure (CPAP) therapy has been established as the treatment of SAS. Double product (W-P = systolic blood pressure x heart rate) was reported to be a good predictor for cardiovascular disease. This study was designed to test whether CPAP could reduce W-P in SAS patients. Design and method: Patients diagnosed as SAS by polisomnography (PSG) examined in our hospital from April 2016 to April 2018 were enrolled (N = 67, male 78.3%, 60.4 ± 14.3 years). 11 cases of the subjects had examined PSG under wearing CPAP. W-P was calculated by casual blood pressure and heart rate measured on the PSG enforcement day. The association between W-P and parameters including age, sex, BMI, abdominal circumference, blood tests date, urine albumin, and various SAS indexes were examined. Results: Casual blood pressure and heart rate were 124.8 ± 19.2/79.1 ± 15.9 mmHg and 78.6 ± 13.4 bpm. W-P in the group with CPAP (8786.7 ± 1451.7) was significantly decreased compared with the group without CPAP (10127.7 ± 2826.5, p < 0.05). The urine protein level (R = 0.43, p < 0.05) and the plasma BNP level (R = 0.45, p < 0.005) were related to W-P. Multivariate regression analysis adjusted for known risk factors also indicated that the urine protein level was independent factor to determine elevated W-P (beta = 0.57, p < 0.05). Conclusions: W-P was related to a hypertensive target organ damage in SAS patient. The CPAP therapy can decrease W-P and may reduce the risk of future cardiovascular disease.