Do the effects of blood pressure control on the progression of diabetic nephropathy depend on disease stage?

Abstract

To determine whether the control of blood pressure has a consistent effect on the progression of diabetic nephropathy with macroalbuminuria in diabetic patients with differing serum levels of creatinine, we evaluated the relationship between mean blood pressure and the yearly rate of increase in serum creatinine concentration in two groups: one with macroalbuminuria and a serum creatinine concentration less than 2 mg/100 ml (group 1), and the other with macroalbuminuria and a serum creatinine concentration of 2 mg/100 ml or more (group 2). Both groups showed a positive relationship between the mean blood pressure and the yearly rate of increase in serum creatinine concentration. However, when the yearly rate of increase in serum creatinine concentration was compared in patients from both groups with matched mean blood pressures of less than 100 mmHg, it was greater in patients of group 2 than in patients of group 1. Thus, although a beneficial effect of blood pressure control on the progression of diabetic nephropathy was found in both groups, the effect was less in patients with macroalbuminuria and a serum creatinine concentration of 2 mg/100 ml or more when mean blood pressure was controlled at less than 100 mmHg.