Effects Of Blood Pressure Variability On Renal Function In Prehypertensive Population

Objective To investigate the correlation between blood pressure variability and the early renal injury in prehypertensive population.Methods127 pre-hypertensive subjects treated in the Second Hospital of Jilin University from January 2015 to December 2016 were involved and divided into two groups according to the levels of microalbuminuria(m Alb): the simple prehypertension group(Group A,m Alb<0.15 g ·L-1,n=96)and the prehypertension with early renal injury group(Group B,m Alb ≥ 0.15 g ·L-1,n=31).All subjects were treated with 24-hour ambulatory blood pressure(24h ABPM)to compare the difference of general data,blood pressure parameters,standard deviation(SD)and coefficient of variation(CV)of blood pressure within 24 hours,daytime and nighttime between the two groups,univariate logistic regression model and multivariate logistic regression model were used to analyze the correlation between general data,blood pressure parameters,BPV and the early renal injury in prehypertensive population of the two groups of subjects.Results General data analysis showed that the difference of the general data(including age,fasting blood glucose,body mass index,triacyglycerol,high density lipoprotein cholesterol,low density lipoprotein cholesterol,serum creatinine,urea nitrogen,cystatin C,blood uric acid,estimated glomerular filtration rate)between the two groups were not statistically significant(P>0.05).The parameters of blood pressure analysis showed that the difference of 24-hour average diastolic blood pressure(24h DBP),daytime average diastolic pressure(d DBP),nighttime average systolic pressure(n SBP),24-hour ambulatory pulse pressure(24h PP),dynamic pulse pressure index(PPI)and nighttime blood pressure decrease rate between the two groups was statistically significant(P<0.05),while there was no significant difference in 24-hour average systolic pressure(24h SBP),daytime average systolic pressure(d SBP)and nighttime average diastolic pressure(n DBP)between the two groups(P>0.05).The results of blood pressure variability analysis showed that the difference of 24-hour systolic blood pressure standard deviation(24h SSD),24-hour diastolic pressure standard deviation(24h DSD),daytime systolic pressure standard deviation(d SSD),nighttime systolic pressure standard deviation(n SSD),nighttime diastolic pressure standard deviation(n DSD),24-hour systolic pressure coefficient of variation(24h SCV),24-hour diastolic pressure coefficient of variation(24h DCV),daytime systolic pressure coefficient of variation(d SCV),nighttime systolic pressure coefficient of variation(n SCV)and nighttime diastolic pressure coefficient of variation(n DCV)between the two groups was statistically significant(P<0.05),and there was no significant difference in daytime diastolic pressure standard deviation(d DSD)and daytime diastolic blood pressure coefficient of variation(d DCV)between the two groups(P>0.05).Multivariate logistic regression analysis showed that 24 h DBP,n SBP,24 h PP,PPI,nighttime blood pressure decrease rate,n SSD,24 h SCV and n SCV were influences of the early renal injury in prehypertensive population.The risk of the early renal injury in prehypertensive population increased when 24 h DBP decreased,n SBP increased,24 h PP and PPI increased,nighttime blood pressure decrease rate decreased,n SSD,24 h SCV and n SCV increased.Conclusion(1)The early renal injury in prehypertension population is closely related to decreasing 24-hour average diastolic blood pressure,increasing nighttime average systolic pressure,increasing pulse pressure,weakening blood pressure circadian rhythm,increasing 24-hour blood pressure variability and nighttime systolic blood pressure variability.(2)The24h PP and PPI of people in the prehypertension with early renal injury group were higher than those in the simple prehypertension group,which suggested that atherosclerosis might be one of the mechanisms of renal injury in prehypertension population.