Level of renal function and serum erythropoietin levels independently predict anaemia post-renal transplantation.

BACKGROUND

Post-renal transplant anaemia is a potentially reversible cardiovascular risk factor. Graft function, immunosuppressive agents and inhibition of the renin-angiotensin system have been implicated in its aetiology. The evaluation of erythropoietin (EPO) levels may contribute to understanding the relative contributions of these factors.

METHODS

Two-hundred and seven renal transplant recipients attending the Belfast City Hospital were studied. Clinical and laboratory data were extracted from the medical records and laboratory systems.

RESULTS

Of the 207 patients (126 male), 47 (22.7%) were found to be anaemic (males, haemoglobin (Hb)<12 g/dl, females Hb<11 g/dl). The anaemic group had a significantly higher mean serum creatinine level (162.8 micromol/l vs 131.0 micromol/l, P<0.001) and lower mean estimated glomerular filtration rate (eGFR) (41.5 ml/min vs 54.9 ml/min, P<0.001) than the non-anaemic group. Individual immunosuppressive regimens were comparable between those with and those without anaemia. Angiotensin converting enzyme inhibitor (ACE-I) or angiotensin receptor blocker (ARB) administration was not more prevalent in those with anaemia compared with those without (36.2 vs 38.8%, P=0.88). There was a significant inverse correlation between Hb levels and serum EPO levels (R=-0.29, P<0.001), but not between EPO levels and eGFR (R=0.02, P=0.74). Higher EPO levels were predictive of anaemia, independent of eGFR in multivariate analysis.

CONCLUSION

Anaemia is common in post-renal transplant patients. The levels of renal function and serum EPO and not immunosuppressive regimens or ACE-I/ARB use, are strong and independent predictors of anaemia.