Relationship Between Urinary Protein Components And Age-related Changes Of Glomerular Filtration Rate And Carotid Intima-media Thickness In Healthy Pepole

ObjectTo observe age-related changes of glomerular filtration rate (GFR), carotid intima-media thickness (C-IMT) and urinary albumin(ALB), transferrin(TRF) and beta-2-microglobulin(β2-MG) in healthy population. And to evaluate the relationship between the three protein components and early signs of kidney and cardiovascular age-related changes, namely GFR and C-IMT in order to find the protein which can be an indicator for the renal and cardiovascular transformation from normal changes to pathological lesions in the aging process.MethodsHealthy participants (n=80) screening with history-taking, physical examination and laboratory tests were divided into four age groups (35-44 years, 45-54 years, 55-64 years,≥65 years), the proportion of male and female was 1:1 in every group (n=20). GFR was estimated by the modification of diet in renal disease (MDRD). C-IMT was measured through carotid ultrasonography. ALB, TRF andβ2-MG were corrected with creatinine (Cr) (ACR,TRF/Cr,β2-MG/Cr).Results1. eGFR decreased and C-IMT increased with age. Compared to the other three groups, both decrease of eGFR and increase of C-IMT were significant in age group≥65(P < 0.05).2. Blood pressure and blood lipid increased with age among normal range. Significant increases of systolic pressure (SBP), diastolic pressure (DBP), triglyceride (TG), total cholesterol (TC) started from the age group 45-54 (P<0.05) , while that of pulse pressure (PP) and low density lipoprotein cholesterol (LDL-C) started from 65 years old (P< 0.05). eGFR was negatively correlated with SBP, PP and BMI (r=-0.346, -0.373, -0.257, all P<0.05). C-IMT was positively correlated with TG, TC (r=0.234, 0.251, all P <0.05).3. ACR,TRF/Cr andβ2-MG/Cr had no statistical difference among four groups (P>0.1). And they were all not correlated with eGFR or carotid IMT(P>0.1).Conclusions1. eGFR decreased and C-IMT increased with age, which indicated that eGFR and C-IMT can be the markers for renal and cardiovasular aging.2. Blood pressure and blood lipid increased with age among normal range, which could have "potential" effects on renal and cardiovasular aging.3. ACR,TRF/Cr,β2-MG/Cr had no significant changes in the aging process, and correlated with neither eGFR nor carotid IMT, and can't be the indicators for the renal and cardiovascular transformation from normal changes to pathological lesions in the aging process.