Only large reductions in concentrations of natriuretic peptides (BNP and NT-proBNP) are associated with improved outcome in ambulatory patients with chronic heart failure.
BACKGROUND
Concentrations of B-type natriuretic peptides (BNPs), including N-terminal pro-B-type natriuretic peptide (NT-proBNP), can be used to estimate prognosis in chronic heart failure. Large biologic variability, however, limits the usefulness of serial measurements in individual patients. As a result, the magnitude of change in peptide concentrations that is clinically meaningful remains to be established.


METHODS
We studied 172 New York Heart Association class III-IV outpatients. Primary endpoints were death/transplantation or heart failure hospitalization. The magnitude of peptide changes was categorized as no change (<20% increase or decrease from enrollment), > or =20% to < or =80% increase or decrease; and >80% increase or decrease. Changes were also assessed using cutpoints (500 ng/L for BNP and 1000 ng/L for NT-proBNP).


RESULTS
Fifty-two patients died or received transplants during the course of the study. Risk reduction for heart failure hospitalization was demonstrated only for BNP decreases of >80% from enrollment [hazard ratio (HR) 0.318, P = 0.0315]. BNP increases from less than to more than the prespecified cutpoint of 500 ng/L were associated with increased mortality risk (HR 2.101, P = 0.0069), whereas decreases from more than to less than the cutpoint did not reduce risk. NT-proBNP decreases from more than to less than the cutpoint of 1000 ng/L were associated with reduced risk of death/transplantation (HR 0.119, P = 0.0354).


CONCLUSIONS
BNP increases from less than to more than the cutpoint were associated with increased risk of events, whereas further increases did not add to risk. In contrast, only substantial natriuretic peptide decreases (>80%) reduced risk. These data suggest that only robust decreases in natriuretic peptide concentrations should be targeted to reduce mortality and heart failure-related hospitalizations.
Miller
Wayne L
WL
Cardiovascular Division, Mayo Medical Center, Rochester, MN, USA. miller.wayne@mayo.edu
Hartman
Karen A
KA
Grill
Diane E
DE
Burnett
John C
JC
Jaffe
Allan S
AS
D000368:Aged; D000369:Aged, 80 and over; D000553:Ambulatory Care; D015415:Biomarkers / Q000097:blood; D002908:Chronic Disease; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000097:blood* / Q000175:diagnosis* / Q000401:mortality / Q000628:therapy; D016027:Heart Transplantation; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D011379:Prognosis; D011446:Prospective Studies; D011863:Radioimmunoassay; D015203:Reproducibility of Results; D012307:Risk Factors; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D016896:Treatment Outcome
D015415:Biomarkers; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain