To evaluate alternative methods of calculating the albumin excretion rate (AER) in the absence of complete and accurate patient documentation, since microalbuminuria in patients with diabetes mellitus is associated with serious complications and since patients often make errors in recording the volume and timing of urine collection, making AER calculations inaccurate.
Recruitment sites, including all native reserves, across southern Alberta.
Population-based group of 1286 subjects with diabetes mellitus participating in the Southern Alberta Study of Diabetic Retinopathy.
Timed AERs were measured in the subjects; urinary albumin concentration was measured by radioimmunoassay.
A formula for the prediction of AER was based on the clinical data from the subjects. Several factors were considered in developing the formula: insulin-using status, weight, sex and urine and serum creatinine concentrations.
A mathematical model for estimation of the AER was developed; incorporation of insulin use, sex and weight provides a more accurate estimate of AER. According to this model, women typically appear to have a lower AER than men and heavier people appear to have a higher AER than people with lower body weight.
The use of mathematical formulae to calculate the AER provides an accurate estimate of the AER, particularly when data related to the volume and timing of urine collection are missing. These formulae will be valuable in large epidemiologic screening programs.