Management of Renin-Angiotensin-Aldosterone System Blockade in Kidney Transplant Recipients

Angiotensin converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) are the cornerstone treatment in chronic kidney disease patients. Despite facilitating a reduction in blood pressure and albuminuria, there are insufficient data in kidney transplant recipients (KTRs). They are often administered for hypertension and polycythemia treatment. The aim of this study was to investigate the frequency and route of administration of ACEIs and ARBs and their early clinical effects in the KTR population. In a cross-sectional, retrospective study we analyzed 874 medical records of all KTRs treated in our unit in 2014. A total of 391 KTRs (44.7%) using ARBs or ACEIs were qualified for the study. The primary reasons for renin-angiotensin-aldosterone system antagonist administration were hypertension (59.1%), polycythemia (19.2%), and proteinuria (18.2%). Among the studied KTRs, 86.7% of patients were treated with ACEIs and 12.2% were treated with ARBs. The majority of patients treated with ACEIs and ARBs received these agents in a dose range below 25% and between 25% and 49% of their maximal dose, respectively. Both the mean serum creatinine level and estimated glomerular filtration rate (chronic kidney disease epidemiology collaboration) remained fairly stable and urine protein excretion (g/24 hours) was significantly reduced after 3 months of ACEI and ARB therapy. The serum potassium level increased significantly, while hemoglobin concentration dropped significantly. In KTRs, renin-angiotensin-aldosterone system antagonists were applied mainly due to hypertension, proteinuria, and polycythemia. ACEIs and ARBs were effective in the reduction of proteinuria and hemoglobin, but graft function was stable and the increase of serum potassium was not of clinical significance.