Blog entry by Arif Khwaja
Interesting data published in this months JASN again challenges the ‘one-size fits all’ approach of many guidelines in nephrology. The Correction of Anemia and PRogression of Renal Insufficiency in Transplant patients (CAPRIT) study from Amiens France, was an open label RCT that randomised patients to receive epoietin-beta to achieve either a normal haemoglobin (13-15g/dl) or a lower haemoglobin (10.5-11.5g/dl). There was no difference in baseline characteristics of the 125 patients who were randomised to the study. At 6 and 12 months the normal haemoglobin group had improvements in quality of life scores compared to the lower haemoglobin group. At 2 years progression to ESRD and return to dialysis occurred in 3 patients (4.8%) in the normal haemoglobin group and 13 patients (21%) in the low haemoglobin group (P=0.01) The death-censored graft survival at 2 years was 94.6% in normal haemoglobin group compared to 80.0% in the low haemoglobin group (P=0.01). The primary outcome was difference in eCrCl by Cockroft-Gault. At year 2, the mean eCrcl decreased by 2.4±1.1 ml/min per 1.73 m2in the normal haemoglobin group and 5.9±1.1 ml/min per 1.73 m2in the low haemoglobin group (P=0.03). There was no increase in CV events in the normal haemoglobin group. Theese results contrast the epo studies in the CKD population where normalisation of haemoglobin was harmful – TREAT, CHOIR, CREATE.
So is this a practice changing paper? I don’t think so because the study was much, much smaller than the CKD trials with a lower prevalence of cardiovascular disease – therefore the study may simply have been underpowered to detect differences in adverse cardiovascular events. Postulated mechanisms by which epo may improve transplant outcomes include a possible immunomodulatory effect or correction of tissue hypoxia and clearly warrant further investigation. Furthermore the potential impact of epo on malignancy could not be evaluated.
What the study does do is highlight the need for a larger multicentre RCT to address the issue of optimal haemoglobin in a transplant patient and the problems of 'extrapolating' guidelines from one patient group to another.
See Correction of Postkidney Transplant Anemia Reduces Progression of Allograft Nephropathy
Gabriel Choukroun, Nassim Kamar, Bertrand Dussol, Isabelle Etienne, Elisabeth Cassuto-Viguier, Olivier Toupance, François Glowacki, Bruno Moulin, Yvon Lebranchu, Guy Touchard, Maïté Jaureguy, Nicolas Pallet, Yannick Le Meur, Lionel Rostaing, Frank Martinez, and for the CAPRIT study Investigators. J Am Soc Nephrol 2012;23 360-368