Does antihypertensive treatment in normotensive patients with diabetic nephropathy alter the progression of kidney failure? We have evaluated studies of renal function which either assessed the effects of different therapeutic blood pressure (BP) goals, or the effects of antihypertensive therapy within the normotensive BP range. Need for renal replacement therapy was regarded as the most valid end point for assessment of deterioration of nephropathy, and change in the glomerular filtration rate (GFR) was regarded as a valid surrogate parameter. Five randomised controlled trials (RCTs) which included normotensive and hypertensive type 1 and type 2 diabetic patients have investigated the effect of lowering of BP within the normotensive range, or from hypertensive values to within the normotensive range. Albumin excretion in urine decreased in the groups randomised to lower BP values, but none of the trials demonstrated any beneficial effect of this intervention on the progression of kidney failure as assessed by the course of GFR. In conclusion, in diabetic patients with microalbuminuria or overt nephropathy, there is no evidence in the literature from RCTs for a beneficial effect of lowering BP within the normotensive range on the risk of kidney replacement therapy or on the loss of glomerular function.
Cooper MEPathogenesis, prevention, and treatment of diabetic nephropathy. Lancet1998;352:213-19.
2.
Lewis EJ, Hunsicker LG, Bain RP, Rohde RDThe effect of angiotensin-converting-enzyme inhibition on diabetic nephropathy . N Engl J Med1993;329:1456-62.
3.
Björck S., Mulec H., Johnsen SA, Norden G., Aurell M.Renal protective effect of enalapril in diabetic nephropathy. BMJ1992;304:339-42.
4.
Bauer JH, Reams GP, Hewett J. et al. A randomised, double-blind, placebo-controlled trial to evaluate the effect of enalapril in patients with clinical diabetic nephropathy. Am J Kidney Dis1992;20:443-57.
5.
Elving LD, Wetzels JMF, van Lier HJJ, de Nobel E., Berden JHM.Captopril and atenolol are equally effective in retarding progression of diabetic nephropathy. Diabetologia1994 ;37:604-09.
6.
Parving HH, Rossing P.The use of antihypertensive agents in prevention and treatment of diabetic nephropathy. Curr Opin Nephrol Hypertens1994 ;3:292-300.
7.
Rossing P., Tarnow L., Boelskifte S., Jensen BR, Nielsen FS, Parving HHDifferences between nisoldipine and lisinopril on glomerular filtration rates and albuminuria in hypertensive IDDM patients with diabetic nephropathy during the first year of treatment. Diabetes1997 ;46:481-7.
8.
Sawicki PTStabilisation of glomerular filtration rate over two years in patients with diabetic nephropathy and intensified therapy regimes. Nephrol Dial Transplant1997;12:1890-9.
9.
Hovind P., Rossing P., Tarnow L., Smith UM, Parving HHProgression of diabetic nephropathy. Kidney Int2001;59:702-09.
10.
Rossing P., Hougaard P., Parving HHRisk factors for development of incipient and overt nephropathy in Type 1 diabetic patients. Diabetes Care2002 ;25:859-64.
11.
American Diabetes Association.Diabetic Nephropathy. Diabetes Care2002;25(Suppl 1):S85-S89.
12.
Sign.Management of diabetic nephropathy. http://www.sign.ac.uk/guidelines/fulltext/55/section5.html (accessed 13 February 2003).
13.
Ramsay LE, Williams B., Johnston GD et al. Guidelines for management of hypertension: report of the third working party of the British Hypertension Society. J Hum Hypertens1999;13:569-92.
Clarke M, Oxman AD, editors. Cochrane Reviewers' Handbook4.1.6 [updated January 2003 ]. http://www.cochrane.de/cochrane/handbook/handbook.htm (accessed 13 February 2003).
16.
Jadad AR, Moore RA, Carroll D. et al. Assessing the quality of reports of randomized clinical trials: is blinding necessary?Control Clin Trials1996;17:1-12.
17.
Schrier RW, Estacio RO, Esler A., Mehler P.Effects of aggressive BP control in normotensive type 2 diabetic patients on albuminuria, retinopathy and strokes. Kidney Int2002;61:1086-97.
18.
Estacio RO, Jeffers BW, Gifford N., Schrier RWEffect of BP control on diabetic microvascular complications in patients with hypertension and type 2 diabetes. Diabetes Care2000;23(Suppl 2):B54-B64.
19.
Lewis JB, Berl T., Bain RP, Rohde RP, Lewis EJEffect of intensive BP control on the course of type 1 diabetic nephropathy . Am J Kidney Dis1999;34:809-17.
20.
Parving HH, Hommel E., Jensen BR, Hansen HPLong-term beneficial effect of ACE inhibition on diabetic nephropathy in normotensive type 1 diabetic patients. Kidney Int2001;60:228-34.
21.
Viberti G., Mogensen CE, Groop LC, Pauls JFEffect of captopril on progression to clinical proteinuria in patients with insulin-dependent diabetes mellitus and microalbuminuria. JAMA1994;271:275-9.
22.
Parving HH, Hommel E., Damkjaer Nielsen M., Giese J.Effect of captopril on BP and kidney function in normotensive insulin dependent diabetics with nephropathy. BMJ1989;299:533-6.
