Strict glycaemic control in diabetic patients with CKD or ESRD: beneficial or deadly?

Several large randomized controlled trials including the Diabetes Control and Complications Trial in type 1 diabetes [1] and the UK Prospective Diabetes Study [2] as well as the Kumamoto Study [3] in type 2 diabetes indicate that good glycaemic control can reduce the risk of nephropathy. More recently, the ADVANCE trial [4] documented in subjects with type 2 diabetes (T2DM) that strict glycaemic control (mean HbA1c: 6.5%) in comparison with the standard control (mean HbA1c: 7.3%) is associated with a significant reduction in renal events, including onset of or worsening of nephropathy [hazard ratio (HR) 0.79; P = 0.006], new-onset microalbuminuria (HR 0.91; P = 0.02) and, in particular, development of macroalbuminuria (HR 0.70; P < 0.001). Moreover, patients with macroalbuminuria and chronic kidney disease (CKD; eGFR 60 mL/min/ 1.73 m at baseline) had a 3.2-fold higher risk for cardiovascular (CV) events and a 22.2-fold higher risk for renal events compared with patients who had neither risk factor. In a study on kidney plus pancreas transplantation in type 1 diabetic patients, Morath et al. [5] had shown that metabolic control improves long-term renal allograft and patient survival. A recent Austrian cohort study [6] of 798 first renal allograft recipients with a diagnosis of diabetes mellitus prior to transplantation also showed that glucose control was significantly associated with patient and graft survival after renal transplantation.