Temporal trajectory of B-type natriuretic peptide in patients with CKD stages 3 and 4, dialysis, and kidney transplant.
OBJECTIVE
B-type natriuretic peptide (BNP) concentration predicts outcome in patients undergoing dialysis. Because survival and cardiovascular risk change across the CKD continuum, serial changes in BNP were compared in patients at different CKD stages and after kidney transplantation.


METHODS
Patients with CKD stages 3 and 4 (CKD 3-4), dialysis patients, and kidney transplant recipients (KTRs) from one center had two measurements of BNP taken a median of 161 days apart in 2003-2004 and were followed until July 2012. Both BNP-32 (Triage BNP; Biosite Diagnostics) and NT-BNP-76 (proBNP; Roche Diagnostics) were assayed. The interaction between change in log-transformed BNP concentration over time and patient group was tested by fitting regression models on panel data with random effects. Survival after the second measurement was compared by tertile of change in BNP.


RESULTS
Patients with CKD 3-4 (n=48), dialysis patients (n=102), and KTRs (n=73) were followed for a median of 5.7, 4.8, and 5.9 years, respectively. The interaction between patient group and BNP measurements over time was significant for NT-BNP-76 (P<0.001) and BNP-32 (P<0.01). Median NT-BNP-76 increased in dialysis patients and those with CKD 3-4 from 3850 pg/ml (interquartile range [IQR], 1776-12,323 pg/ml) to 18,830 pg/ml (IQR, 6114-61,009 pg/ml; P<0.001) and from 698 pg/ml (IQR, 283-2922 pg/ml) to 2529 pg/ml (IQR, 347-9277 pg/ml; P=0.002), respectively. Change was not significant for KTRs or comparisons made with BNP-32. Survival rate was significantly lower for patients with the highest tertile of change in NT-BNP-76 among patients with CKD 3-4 (P=0.02), but not in the dialysis or KTR groups. In 11 patients who received a kidney transplant during the study, median NT-BNP-76 decreased from 9607 pg/ml (IQR, 2292-31,282 pg/ml) to 457 pg/ml (IQR, 203-863 pg/ml) after transplant (P<0.01).


CONCLUSIONS
The temporal trajectory of BNP differs between dialysis patients and those with CKD 3-4 and KTRs. This has important implications for the development of BNP-guided management strategies in CKD.
Department of Renal Medicine, Eastern Health Clinical School, Monash University, Victoria, Australia; Matthew.Roberts@easternhealth.org.au.
Matthew A
MA
Roberts
Department of Medicine, University of Melbourne, Victoria, Australia; Department of Cardiology, and.
David L
DL
Hare
Melbourne Pathology Service, Collingwood, Victoria, Australia.
Ken
K
Sikaris
Department of Medicine, University of Melbourne, Victoria, Australia; Department of Nephrology, Austin Health, Victoria, Australia; and.
Francesco L
FL
Ierino
D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D006801:Humans; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D006435:Renal Dialysis; D051436:Renal Insufficiency, Chronic / Q000097:blood* / Q000628:therapy*; D012720:Severity of Illness Index; D015996:Survival Rate; D013997:Time Factors
D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain
B-type natriuretic peptide; cardiovascular disease; chronic kidney disease; dialysis; kidney transplant