Residual Renal function (RRF) has an important role in the overall morbidity and mortality in hemodialysis patients. The role of angiotensin-converting enzyme inhibitor (ACEi) in preserving renal function in chronic proteinuric nephropathies is well documented. We test the hypothesis that enalapril (an ACEi) slows the rate of decline of RRF in patients starting hemodialysis. A prospective, randomized open-label study was carried out. 42 patients were randomized in two groups either in treatment with enalapril or no treatment at all. Our study has proven that enalapril has a significant effect on preserving residual renal function in patients starting dialysis at least during the first 12 months from the initiation of the hemodialysis. Further studies are necessary in order to investigate the potential long-term effect of ACEi on residual renal function and on morbidity and mortality in patients starting hemodialysis. 1. Introduction The effect of residual renal function (RRF) in patients with end stage renal disease in peritoneal dialysis is extensively studied and is associated with lower morbidity and mortality. The CANUSA study has proven that for every 0.5？mL/min additional glomerular filtration rate (GFR) there was a 9% lower risk of death in peritoneal dialysis patients with RRF [1]. In hemodialysis patients also, the pivotal role of residual renal function is well documented [2, 3]. It has a major contribution in total solute clearance, especially in removing middle as well as small solute proteins [4, 5]. One of RRF major benefits is the optimal control of fluid balance, with extreme importance in blood pressure control, decreased left ventricular hypertrophy, and reduction of cardiovascular disease [6]. It also reflects the residual homeostasis mechanism for calcium and phosphorus balance [7] and erythropoietin residual synthesis. Patients with RRF have higher levels of hemoglobin due to higher levels of endogenous erythropoietin [8]. RRF has an overall beneficial effect on quality of life mainly because it offers better fluid balance, higher haemoglobin, better nutritional status, better phosphate control, and lower accumulation of β2-microglobulin [9]. RRF declines with time on dialysis [10]. Various studies have proven that peritoneal dialysis is better in preserving RRF than hemodialysis but very few studies have investigated in therapeutic interventions for preserving RRF in hemodialysis patients. The effect of angiotensin-converting enzyme inhibitor (ACEi) on reducing the rate of decline of GFR in proteinuric nephropathies and its
References
[1]
“Adequacy of dialysis and nutrition in continuous peritoneal dialysis: association with clinical outcomes. Canada-USA (CANUSA) Peritoneal Dialysis Study Group,” Journal of the American Society of Nephrology, vol. 7, no. 2, pp. 198–207, 1996.
[2]
F. Termorshuizen, F. W. Dekker, J. G. Van Manen, J. C. Korevaar, E. W. Boeschoten, and R. T. Krediet, “Relative contribution of residual renal function and different measures of adequacy to survival in hemodialysis patients: an analysis of the Netherlands cooperative study on the adequacy of dialysis (NECOSAD)-2,” Journal of the American Society of Nephrology, vol. 15, no. 4, pp. 1061–1070, 2004.
[3]
D. Shemin, A. G. Bostom, P. Laliberty, and L. D. Dworkin, “Residual renal function and mortality risk in hemodialysis patients,” American Journal of Kidney Diseases, vol. 38, no. 1, pp. 85–90, 2001.
[4]
A. C. Fry, D. K. Singh, S. M. Chandna, and K. Farrington, “Relative importance of residual renal function and convection in determining beta-2-microglobulin levels in high-flux haemodialysis and on-line haemodiafiltration,” Blood Purification, vol. 25, no. 3, pp. 295–302, 2007.
[5]
G. Montini, G. Amici, S. Milan et al., “Middle molecule and small protein removal in children on peritoneal dialysis,” Kidney International, vol. 61, no. 3, pp. 1153–1159, 2002.
[6]
A. Y. M. Wang, M. Wang, J. Woo et al., “A novel association between residual renal function and left ventricular hypertrophy in peritoneal dialysis patients,” Kidney International, vol. 62, no. 2, pp. 639–647, 2002.
[7]
G. Morduchowicz, J. Winkler, J. R. Zabludowski, and G. Boner, “Effects of residual renal function in haemodialysis patients,” International Urology and Nephrology, vol. 26, no. 1, pp. 125–131, 1994.
[8]
E. Erkan, M. Moritz, and F. Kaskel, “Impact of residual renal function in children on hemodialysis,” Pediatric Nephrology, vol. 16, no. 11, pp. 858–861, 2001.
[9]
M. P. Merkus, et al., “Quality of life in patients on chronic dialysis: self assessment 3 months aftes rhe start if treatmen,” American Journal of Kidney Diseases, vol. 29, no. 4, pp. 584–592, 1997.
[10]
J. Rottembourg, B. Issad, J. L. Gallego et al., “Evolution of residual renal function in patients undergoing maintenance haemodialysis or continuous ambulatory peritoneal dialysis,” Proceedings of the European Dialysis and Transplant Association, vol. 19, pp. 397–403, 1983.
[11]
E. J. Lewis, L. G. Hunsicker, R. P. Bain, and R. D. Rohde, “The effect of angiotensin-converting-enzyme inhibition on diabetic nephropathy,” The New England Journal of Medicine, vol. 329, no. 20, pp. 1456–1462, 1993.
[12]
G. Maschio, D. Alberti, G. Janin et al., “Effect of the angiotensin-converting-enzyme inhibitor benazepril on the progression of chronic renal insufficiency,” The New England Journal of Medicine, vol. 334, no. 15, pp. 939–945, 1996.
[13]
European Best Practice Guidelines for Haemodialysis, “Section I. Measurement of renal function, when to refer and when to start dialysis,” Measurement of Renal Function Nephrol Dial Transplant, vol. 17, supplement 7, pp. 7–9, 2002.
[14]
J. T. McCarthy, B. M. Jenson, D. P. Squillace, and A. W. Williams, “Improved preservation of residual renal function in chronic hemodialysis patients using polysulfone dialyzers,” American Journal of Kidney Diseases, vol. 29, no. 4, pp. 576–583, 1997.
[15]
R. Maiorca, G. Brunori, R. Zubani et al., “Predictive value of dialysis adequacy and nutritional indices for mortality and morbidity in CAPD and HD patients. A longitudinal study,” Nephrology Dialysis Transplantation, vol. 10, no. 12, pp. 2295–2305, 1995.
[16]
M. W. Taal and B. M. Brenner, “Renoprotective benefits of RAS inhibition: from ACEI to angiotensin II antagonists,” Kidney International, vol. 57, no. 5, pp. 1803–1817, 2000.
[17]
P. K. Li, K. M. Chow, T. Y. Wong, et al., “Effects of an ACEi on residual renal function in patients receiving peritoneal dialysis,” Annals of Internal Medicine, vol. 139, no. 2, pp. 105–112, 2003.
[18]
A. Akbari, G. Knoll, D. Ferguson, B. McCormick, A. Davis, and M. Biyani, “Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers in peritoneal dialysis: systematic review and meta-analysis of randomized controlled trials,” Peritoneal Dialysis International, vol. 29, no. 5, pp. 554–561, 2009.
[19]
P. Ruggenenti, A. Perna, G. Gherardi et al., “Renoprotective properties of ACE-inhibition in non-diabetic nephropathies with non-nephrotic proteinuria,” The Lancet, vol. 354, no. 9176, pp. 359–364, 1999.
[20]
J. H. Bauer, G. P. Reams, J. Hewett et al., “A randomized, double-blind, placebo-controlled trial to evaluate the effect of enalapril in patients with clinical diabetic nephropathy,” American Journal of Kidney Diseases, vol. 20, no. 5, pp. 443–457, 1992.
[21]
J. Hartmann, H. Fricke, and H. Schiffl, “Biocompatible membranes preserve residual renal function in patients undergoing regular hemodialysis,” American Journal of Kidney Diseases, vol. 30, no. 3, pp. 366–373, 1997.
[22]
C. Caramelo, R. Alcazar, P. Gallar et al., “Choice of dialysis membrane does not influence the outcome of residual renal function in haemodialysis patients,” Nephrology Dialysis Transplantation, vol. 9, no. 6, pp. 675–677, 1994.
[23]
P. Stenvinkel, P. Andersson, T. Wang et al., “Do ACE-inhibitors suppress tumour necrosis factor-α production in advanced chronic renal failure?” Journal of Internal Medicine, vol. 246, no. 5, pp. 503–507, 1999.
