[Association between obstructive sleep apnea and vascular injury in hypertensive patients]

Objective: To investigate the relationship between obstructive sleep apnea (OSA), apnea hypopnea index (AHI) and vascular injury in hypertensive patients. Methods: This cross-sectional study enrolled patients admitted to the Hypertension Department of TEDA International Cardiovascular Hospital from April 2020 to April 2023, who finished portable sleep monitoring. Sleep monitoring indicators, flow-mediated vasodilation (FMD), carotid artery ultrasound, carotid intima-media thickness, cervical and femoral pulse wave conduction velocity (cfPWV), brachial and ankle pulse wave conduction velocity (baPWV) were analyzed. OSA was classified into mild (5 times/h≤AHI<15 times/h), moderate (15≤AHI<30 times/h), and severe (AHI≥30 times/h) based on AHI levels. FMD<6.0% was defined as vascular endothelial injury, and cfPWV>10 m/s and/or baPWV>18 m/s was defined as arterial stiffness. Multivariate logistic regression analysis was used to explore the correlation between AHI, OSA severity and vascular injury, and subgroup analysis was performed in young (age≤45 years) and middle-to-old patients (age>45 years). Sensitivity analysis was performed by excluding patients with diabetes, cerebrovascular disease and coronary heart disease. The correlation between AHI and vascular injury index was analyzed by restricted cubic spline. Results: A total of 555 adult hypertensive patients were included, the mean age was (39.7±9.2) years, 422 were males (76.0%), and the prevalence of OSA was 66.7% (370/555). Multivariate logistic regression analysis showed that moderate OSA (OR=2.83, P=0.019) and severe OSA (OR=3.40, P=0.016) were positively correlated with vascular endothelial injury after adjusting for age, sex, body mass index and mean arterial pressure. Subgroup analysis showed that log AHI (OR=1.99, P=0.035), moderate OSA (OR=4.83, P=0.010) and severe OSA (OR=4.64, P=0.015) were associated with vascular endothelial injury in young hypertensive patients. The results of sensitivity analysis were similar to the above results. The results of restricted cubic spline analysis showed that AHI was correlated with FMD (P=0.022), and the slope of the curve was the largest when AHI was between 0 and 10 times/h. There was no correlation between log AHI and OSA severity and carotid intima-media thickening and arterial stiffness (all P<0.05). Conclusions: OSA is associated with vascular endothelial injury in hypertensive patients, especially in young patients.