[Analysis of renal function on 1,743 people of different ages]

To understand and evaluate the currency and correlation between parameters about renal function.

We divided 1,743 people whose ages vary from 20-85 years into six groups(A, B, C, D, E, F). Urinary Mini Albumin, RBP, NAG, osmotic pressure, serum BUN, plasma UA and internal creatinine clearance were measured as parameter about renal function.

There was no obvious difference between the Group A and Group B(P > 0.05); The mean value of urinary NAG and urinary RBP in the two group was 10.9650 +/- 6.5650 and 0.1885 +/- 0.4709; However, when they were compared with the values of C, D, E group respectively, there were prominent differences (P < 0.05 or P < 0.01). Urinary Alb value of Group A is quite different from other groups. No difference exists between urinary Alb value of Group E and Group F(P > 0.05). Internal creatinine clearance decrease by the rate of 8.5%, 17.8%, 29.9%, 42.9% and 56.3% when Groups B, C, D, E and F was compared with Group A; while urinary osmotic pressure and the value of plasma BUN, Cr and UA has no obvious difference between any two groups(P > 0.05).

The clearance of internal creatinine decrease with the growing of the age, especially older than 50 years of age. The parameter about tubular injury increase obviously after 40 years old though it does not change prominently before 50 years old, while it tends to be stable after 70 years old. We think it is during period of 40 to 70 years old that the renal function decreases more rapidly.