Noninvasive Beat-to-beat Blood Pressure Variability For Early Prediction Effect And Monitoring In The Pre-hypertension Stage

Background Hypertension has become one of the important diseases affected human health worldwide, and is also an important risk factor for cardiovascular disease. Long-term high blood pressure can damage vital organs such as heart, brain, kidney, which seriously affects the health of human. Although treatment and management of hypertension has been more mature, data obtained in clinical practice still depends on blood pressure measurements in outpatient clinic and home blood pressure measurements, which undoubtedly brings a lot of uncertainty and loss of a large number of useful data. In addition, the doctor will face huge difficulties when selecting the method of therapy, and it will eventually endanger the health of patients. Arterial stiffness is a chronic non-inflammatory disease. With the development of economy and the improvement of quality of life, death caused by atherosclerosis increase gradually. Atherosclerosis is a long process of gradual change. So it is a very important means of prevention of various cardiovascular diseases that early detection and intervention process of atherosclerosis. Noninvasive beat-to-beat blood pressure monitoring is that measuring blood pressure values every beat and really no interval between consecutive measurements. Compared with the traditional 24-hour ambulatory blood pressure monitoring and follow-up blood pressure monitoring, noninvasive beat-to-beat blood pressure monitoring can more accurately reflect the real-time dynamics of blood pressure. Whether noninvasive beat-to-beat blood pressure variability is closely associated with the development of arterial stiffness, and whether noninvasive beat-to-beat blood pressure variability can identify early arterial alteration in the pre-hypertension stage remains controversial.Objectives 1. Study the relationship between beat-to-beat blood pressure variability and arterial stiffness in healthy adults. 2. Analysis differences of beat-to-beat blood pressure mean level and variability between the offspring of hypertensive parents and the offspring of normotensive parents, and study the role of beat-to-beat blood pressure variability in identifying arterial alteration in the early pre-hypertension stage.Methods 1. Recruiting 101 young Chinese subjects with no family history of high blood pressure, who were aged 21 to 33 years(25.2±2.2). 2. Completing the cold pressor test in wearable medical instrument laboratory, noninvasive continuous monitoring method is used to measure the volunteer's physiological indexes. 3. Analysis the relationship between beat-to-beat blood pressure variability parameters and arterial stiffness in three stages of cold pressor test. 4. Subjects can be divided into the offspring of hypertensive parents group and the offspring of normotensive parents group, and compare differences of beat-to-beat blood pressure variability between two groups.Results 1. We found that the correlation between beat-to-beat blood pressure mean level and pulse wave velocity in each phase of the cold pressor test. 2. The average real variability, successive variation of diastolic blood pressure variability in the cold stimulus phase showed significant correlation with pulse wave velocity. 3. The parameters of heart rate variability showed significant correlation with pulse wave velocity in the cold stimulus phase. 4. The difference in beat-to-beat blood pressure level and heart rate variability between the offspring of hypertensive parents and the offspring of normotensive parents showed statistically significance. These indices included average real variability, standard deviation and successive variation of systolic blood pressure in the cold stimulus phase, average real variability and successive variation of diastolic blood pressure variability in the whole cold pressor test, standard deviation of diastolic blood pressure variability and square root of the mean squared differences of successive R-R intervals in the cold stimulus phase and post-baseline phase, standard deviation of the R-R intervals in the baseline phase and post-baseline phase, the high frequency of the systolic blood pressure variability in the cold stimulus phase, the low frequency of heart rate variability in the baseline phase, and the low frequency / high frequency ratio of the systolic blood pressure variability in the post-baseline phase.Conclusions 1. The advantages of noninvasive continuous monitoring method: noninvasive, convenient operation, continuous measurement. Noninvasive beat-to-beat blood pressure variability is closely related to the process of hardening of the arteries. 2. Atherosclerosis is more likely to occur in the offspring of hypertensive parents, who are more susceptible to hypertension than the offspring of normotensive parents. In conclusion, noninvasive beat-to-beat blood pressure level and variability can potentially play a role in identifying arterial alteration in the pre-hypertension stage.