Blockade of the renin–angiotensin system for the primary prevention of diabetic nephropathy

SUMMARY There is clear evidence for the pathogenic role of the renin–angiotensin system (RAS) in the progression of diabetic kidney. Treatment with either an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker have been shown to reduce proteinuria and preserve renal function in patients with diabetes and chronic kidney disease. While such data provide a strong rationale for early and sustained blockade of the RAS for the primary prevention of kidney disease, clinical trial evidence to support this goal is limited and inconsistent. By contrast, data from observational and clinical trials clearly demonstrate the primacy of blood-pressure control in the development of diabetic kidney disease, especially in hypertensive patients. Whether RAS blockade offers additional benefits for primary prevention, over-and-above blood-pressure control, remains contentious. At best, any ‘independent effects’ on primary prevention are modest, and certainly not the panacea envisaged by many practitioners. ...