Background and objectives: This study investigated whether the slope of estimated GFR is different between nonproteinuric subjects with and without diabetes, and what clinical factors are associated with the GFR slope.Design, setting, participants, & measurements: An observational cohort study was performed in 923 subjects, and the predictive value of baseline variables on the GFR slope was investigated.Results: On the basis of the median 3-yr follow-up and 7 measurements of GFR, GFR slope (%/yr, median and interquartile range) was significantly larger in subjects with diabetes (؊2.39 (؊4.86 to 0.15), n ‫؍‬ 729) than in those without diabetes (؊1.02 (؊4.28 to 1.37), n ‫؍‬ 194), and this difference remained significant with or without presence of hypertension. After adjustments for confounding factors, predictors of GFR decline were found to be baseline high values of glycosylated hemoglobin A 1C (HbA 1C ), GFR, systolic blood pressure, and low plasma total protein in subjects with diabetes, whereas only the latter two were significant in subjects without diabetes. In subjects with diabetes, the high GFR was accounted for by high HbA 1C at baseline, and the predictors of GFR decline differed between those with and without hypertension, or with high and low baseline GFR. Any combination of the predictors showed increased risk for GFR decline.Conclusions: GFR slope is substantially affected by multiple factors at various stages. The degree of chronic hyperglycemia is likely to play a crucial role in elevating GFR and accelerating the decline in patients with type 2 diabetes even from the normoalbuminuric stage.

Urinary albumin excretion is only one risk factor for albuminuria progression and GFR decline, and other important factors were implicated as important for prevention of end-stage renal disease.