Aims: the aim of the study was to analyze glomerular filtration ratio (GFR) changes in diabetic patients assisted by General Practitioners (GPs) evaluating the risk factors related to glomerular function. Methods: patients with diabetes with at least three recorded values of creatinine were recruited in the study and GFR values were estimated. The quarterly percentage change in GFR for each patient was estimated. Nephrotoxic drugs were identified, and glucose-lowering drugs use was described. Linear regression analyses were performed to identify eGFR changes predictors. Results: a total of 545 patients with diabetes were selected. According to the last eGFR values 64 (11.7 %) patients were classified in G1 stage, 277 (50,8 %) in G2, 175 (32.1 %) in G3a, 25 (4.6 %) in G3b and only 4 (0.7 %) in G4. Patients treated with at least one glucose-lowering drugs were 479 (87.9 %), most of them with biguanides (67.0 %). At least one nephrotoxic drug prescription was recorded in 524 (96.1 %) patients; proton pump inhibitors (74.7 %) and NSAIDs (71.6 %) were the most prescription classes. Heart failure, diabetes duration and preserved GFR values were related to reduced eGFR values. Conclusions: patients with diabetes should be more carefully observed regardless of kidney risk factors and GFR values in clinical practice.
