An elevated urinary albumin excretion predicts de novo development of renal function impairment in the general population.

BACKGROUND: We questioned which factors determine the risk for developing renal function impairment. To that purpose, we studied the incidence of newly diagnosed impaired renal function (GFR <60 mL/min/1.73m2) in the PREVEND cohort (N=8592), which is enriched for the presence of albuminuria, and which was first studied in 1997-1998. Of this cohort, 6894 subjects were studied again four years later.
METHODS: Subjects with known renal disease, GFR <60 mL/min, missing GFR values, or sediment abnormalities at the first screening were excluded from the present analysis (N=872). We examined whether albuminuria is associated with the de novo development of an impaired renal function. GFR was 90.3 (SD 16.3) mL/min/1.73m2 at baseline, and 11.6% of the subjects had an albuminuria of more than 30 mg/day.
RESULTS: After a follow-up of four years, 253 subjects (4.2%) were found to have a GFR <60 mL/min/1.73m2. The subjects with newly diagnosed impaired GFR were older, had a higher blood pressure, serum cholesterol, plasma glucose, and urinary albumin excretion at the first examination, and had a lower GFR to start with than those with a GFR >60 at the second evaluation. Subjects with de novo impaired GFR had a comparable BMI and smoked less frequently compared with subjects with GFR >60. In multivariate analysis, urinary albumin excretion was independently predictive for the risk of developing an impaired GFR (P=0.001).
CONCLUSION: Also in the general population, measurement of urinary albumin excretion may prove to be a valuable tool to detect subjects at risk for later development of renal failure, independent of the presence of other cardiovascular risk factors.