One-year eGFR decline rate is a good predictor of prognosis of renal failure in patients with type 2 diabetes.

It is difficult to distinguish the onset of renal function decline from the typical variation in estimated glomerular filtration rate (eGFR) measurements in clinical practice. In this study, we used data analysis incorporating smoothing techniques to identify significant trends despite large amounts of noise. We identified the starting points of meaningful eGFR decline based on eGFR trajectories. This was a retrospective observational study of 2533 type 2 diabetes patients. We calculated 1-year eGFR decline rates from the difference between each eGFR value and that of the previous year. We examined the prediction capacity of 1-year eGFR decline rate for renal prognosis. When we performed receiver operating characteristic analysis, the area under the curve of 1-year eGFR decline rate was 0.963 (95% confidence interval: 0.953-0.973). With a cut-off value of more than 7.5% eGFR decline during a 1-year period, the sensitivity was 98.8% and specificity was 82.3%. The predictive accuracy of 1-year eGFR decline rate for renal prognosis was high.