Intensified treatment of patients with type 2 diabetes mellitus and overt nephropathy

Background: Diabetic nephropathy is the single most common cause of chronic renal failure requiring dialysis. Effective treatment exists, but no clinical audit or large trial has reduced the rate of loss of renal function as effectively as in small groups of intensively managed patients. Aim: To determine the effect of intensive vs. standard medical management on the rate of progression of renal failure in patients with diabetic nephropathy. Design: Prospective randomized controlled study. Methods: Patients with type 2 diabetes and nephropathy were randomly allocated to an intensive group (n = 47) or control group (n = 43). Treatment targets were the same for both groups, but the intensive group were seen as often as required to meet the targets; controls were seen at their normal clinics. The primary end-point was the rate of progression of renal disease in the second year. Results: The groups were well matched at baseline. During follow-up, the intensive group had lower mean SBP, DBP and cholesterol. Median rate of progression of renal failure in the intensive group fell from 0.44 ml/min/month in the first year to 0.14 ml/min/month in the second year, compared to 0.49 ml/min/month and 0.53 ml/min/month in the control group (p = 0.04 for second year). Patients in the intensive group spent significantly less time in hospital. Discussion: Intensive treatment slowed progression of renal disease within 2 years in patients with established diabetic nephropathy. Mean creatinine clearance at the start of the trial was 55 ml/min, so assuming that the rates of progression achieved at the end of the second year persisted, onset of dialysis would be delayed by 20 years in the intensive group compared with the control group.