Introduction
Vascular health indicators, including structural lumen stenosis and functional disorder, reflect the long-term cumulative effects of traditional and unidentified cardiovascular (CV) risk factors before and after clinical vascular events, and can be regarded as an alternative end point index for target organ damage and risk prediction1. Several markers have been considered as the reflection of vascular health, among them endothelial function, arterial stiffness and carotid atherosclerosis are the most common indicators1. Endothelial dysfunction may represent the effect of traditional CV risk factors on vascular health2. Arterial stiffness is increasingly recognized as a surrogate end point for cardiovascular disease (CVD) and as a risk factor for clinical hypertension3, 4. Carotid ultrasound measurement of intima-media thickness (IMT) along with carotid plaque are emerging as the focus of carotid artery ultrasound imaging for CV risk prediction5. Currently, studies on assessing vascular health use only one or more of these indicators6-8. Beijing Vascular Health Stratification (BVHS)was put forward to assess vascular health including all stages of vascular disease progression, from endothelial function to arteriosclerosis to vascular stenosis9. BVHS is a risk prediction tool using subclinical vascular measures such as endothelial function, arterial stiffness, carotid atherosclerotic plaques and artery stenosis by non-invasive detections. Furthermore, traditional risk factors are not included in BVHS, but are used as adjusted confounding factors to analyze the independent predictive role of BVHS.
All the markers are graded as artery functional injury or structural disease or both. Our previous retrospective study found that the BVHS was a comprehensive risk assessment system and was independent of traditional CV risk factors10. However, the previous study did not develop a strict study design and follow-up plan. Therefore, this study was designed as a prospective cohort study to verify the previous research results and further explore the clinical value of BVHS for the prediction of major adverse cardiovascular events (MACEs).