The Association Between Blood Pressure Variation And Decreased Glomerular Filtration Rate In Elderly Hypertensives

Objective To investigate the association between blood pressure variation and decreased glomerular filtration rate in elderly hypertensives.Methods We selected178elderly patients with hypertension, from January2008to March2011. We measured the plasma URIC, and estimated glomerular filtration rate(eGFR) by the Cockcroft-Gault equation was used as an indicator of renal function. We divide the patients into4groups:A group(n=44), B group(n=59), C group(n=46), D group(n=29), according to the GFR class(≥90ml/(min·1.72m2),60～89ml/(min·1.72m2),40～59ml/(min·1.72m2),<40ml/(min·1.72m2)).24h ambulatory blood pressure monitoring(ABPM) was performed and determined fasting plasma glucose(FPG), total cholesterol(TC),Triglyceride(TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), body mass index (BMI)in each patient and compared the difference of each index in four renal function class groups.Result1.Comparison of AMBP parameters in four eGFR(renal fuction) class groupsThe nighttime average systolic blood pressure,24h average pulse pressure, daytime average pulse pressure, nighttime average pulse pressure, morning blood pressure surge,the dipping ratios of nocturnal diastolic pressure were increases follows the eGFR class((P<0.05).And the difference between4groups was regarded significant.The wave amplitude of diastolic blood pressure, the dipping ratios of nocturnal systolic blood pressure and pulse pressure were decreases follows the eGFR class(P<0.05).And the difference between4groups was regarded significant.2.Pearson correlation analysiseGFR negatively related with course of disease (r=-0.381,P=0.023), nighttime average systolic blood pressure(r=-0.342,P=0.045),morning systolic blood pressure surge(r=-0.627,P=0.000),24h average pulse pressure(r=-0.481,P=0.012),nighttime average pulse pressure (r=-0.492,P=0.009),the dipping ratios of nocturnal diastolic blood pressure(r=-0.503, P=0.007); eGFR positively related with nighttime average diastolic blood pressure(r=0.443,P=0.015), wave amplitude of diastolic blood pressure(r=0.518,P=0.002), the dipping ratios of nocturnal systoic blood pressure (r=0.543,P=0.000)and nocturnal pulse pressure(r=0.557,P=0.000).3. Multivariate linear regression analysis(Multiple regression analysis)Multivariate linear regression analysis showed course of disease, nighttime average systolic blood pressure,24h average pulse pressure, nighttime average pulse pressure, morning stolic blood pressure, the dipping ratios of nocturnal systolic blood pressure and pulse pressure were predictors of eGFR, especially nighttime average pulse pressure, the dipping ratios of nocturnal pulse pressure (R2=0.722).Conclusion1.In ederly hypertensive, the abnormality of24h ambulatory blood pressure monitoring circadian rhythm and wave amplitude were gradually aggravated follows the eGFR class,especially the nighttime average systolic biood pressure,morning blood pressure surge,24h average pulse pressure, daytime average pulse pressure, nighttime average pulse pressure, the wave amplitude of diastolic blood pressure and the dipping ratios of blood pressure.2.The abnormality of24h ambulatory blood pressure monitoring circadian rhythm and wave amplitude were closely related with kidney damage in ederly hypertensive,especially increased pulse pressure.