The Relationship Between BNP And Blood Pressure Variability In Hypertensive Patients

Object: By adopting the 24 h Ambulatory blood pressure monitor,the author got 24 hour systolic blood pressure coefficient of variation(24h SCV), 24 hour diastolic blood pressure coefficient of variation(24h DCV), day systolic blood pressure coefficient of variation(d SCV), day diastolic blood pressure coefficient of variation(d DCV), night systolic blood pressure coefficient of variation(n SCV) and night diastolic blood pressure coefficient of variation(n DCV), thus observing the regularity of blood pressure variability(BPV) of patients with essential hypertension(EH), exploring the mechanism that caused the rise of BPV of patients with EH, analyzing the relationship between BPV and BNP in each time bucket, exploring the correlation mechanism between BNP level and BPV, making clear the estimated value of BNP level to BPV of patients with EH. Therefore, more convenient reference data would be offered to the diagnosis, intervention and the evaluation of treatment to EH, decreasing the complication and risks to target organs which might be caused by EH.Methods: 80 simple hypertension patients were picked who received treatment in our department during November 2013 to November 2014, including 43 men and 37 women. Their ages were between 50~83 with average age 66.8±8.6. If permitted, all of them would stop having hypertensive drugs for 3 days. Meanwhile, 35 healthy people who came to receive physical examination were picked as control group, including 19 men and 16 women. Their ages were between 50~80, with their average age 66.6±6.3. Excluding secondary hypertension, serious heart failure, infectious diseases, stress state, valvular heart disease cardiomyopathy, malignant tumor and severe hepatic and renal dysfunction and so on, the author gathered their basic and detailed medical history both of experimental group and control group. 24 h Ambulatory blood pressure monitoring would be done in strict accordance with the instructions of the blood pressure monitor, starting at 8:00am and finishing at 8:00am the next day with blood pressure monitored in each hour, thus the author got 24 h SCV, 24 h DCV, d SCV, d DCV, n SCV and n DCV and calculated the variable coefficient(CV) of blood pressure in each time bucket. After the fasting blood was centrifugated, the serum was collected for testing. The serum BNP was measured by immunofluorescence. The correlation between BPV and serum BNP in each time bucket should be analyzed.Results:1 Compared with that in normal control group, patients’ BPV in hypertension group was greatly higher in each time bucket(P<0.05).2 Compared with that in normal control group, patients’ BNP in hypertension group remarkably raised(P<0.05).3 Linear correlation analysis showed that the serum BNP level was weakly related to the level of blood pressure in each time bucket including 24 h SCV, 24 h DCV, d SCV, d DCV, n SCV and n DCV.(The correlation coefficients were-0.235、0.137、-0.209、0.055、-0.013 �'� 0.192,P>0.05).4 Linear correlation analysis showed that the serum BNP level was positively related to BPV in each time bucket including 24 h SCV, 24 h DCV, d SCV, d DCV, n SCV and n DCV.(The correlation coefficients were 0.701, 0.702, 0.701, 0.693, 0.690 and 0.705, P<0.05).5 Multiple regression analysis showed that the total cholesterol, nocturnal diastolic blood pressure variability and ages can enter the regression equation with serum BNP as the dependent variable(The regression coefficients were 0.571、0.126、0.305,P<0.05).Conclusions: The BPV in each time bucket had a remarkable effect on BNP, among which nocturnal diastolic blood pressure variability was the major factor and BNP was a predictive index to BPV in patients with EH.