Effect Of Changes Of Blood Pressure Level On Renal Function In High Normal Blood Pressure Population

Objectives To investigate the effect of blood pressure on renal function in normal high blood pressure population.Methods In Kailuan cohort,18191 participants who participated in both 2006 survey and 2008 survey and met the inclusion criteria were recruited in this study.After followed up to Dec,31,2015,the cumulative incidence of renal damage in different blood pressure change groups was calculated by Kaplan-Meier method.The cumulative incidence of renal damage in different blood pressure groups was compared with Log-rank-Mantel-Cox test,and the effects of different blood pressure levels on renal function were analyzed by Cox proportional risk model.Results In this study,33.3% of the participants with high normal blood pressure developed hypertension(high normal-hypertension group),47.8% of the participants maintained a steady high normal blood pressure(high normal-high normal blood pressure group),18.9% decreased to normal blood pressure(high normal-normal blood pressure group).In total,the cumulative incidence of renal damage was 9.5%.The cumulative incidence of renal damage in the high normal-hypertension group was 10.9%,which was higher than those in other groups(high normal-normal blood pressure group,7.8%;high normal-high normal blood pressure,9.2%),the difference was statistically significant(P<0.01).The cumulative incidence of urinary protein in high value increased group(6.6%)was significantly higher than that in e GFR decline rate(4.9%),and the cumulative urinary protein incidence rate in men(5.5%)was higher than that in women(4.2%).Multivariate Cox regression analysis(Forward stepwise regression method based on maximum release estimation)showed that,compare with participants in high normal-normal blood pressure group,the risks of renal damage were 1.18(1.03~ 1.36)in participants with high normalhigh normal blood pressure and 1.39(1.20 ~ 1.61)in participants with high normalhypertension group.Conclusions Elevated blood pressure is an independent risk factor for renal damage in individuals with high normal blood pressure after adjusted for co-variables.33.3% of high normal blood pressure may develop into hypertension during 2 years exposure.The cumulative incidence of renal damage in high normal blood pressure population was 9.5%.The increase of blood pressure level in kidney was mainly caused by the increase of urinary protein.We should pay attention to population with high normal blood pressure and increase the kidney damage awareness rate.