Within-person NT-proBNP variability in stable heart failure patients was low (15.5% to 18.9% CV over 14 days to 3 months) and was not associated with renal function, weight, age, or sex.
Observational (n=41)
What is the within-person variability of NT-proBNP in patients with stable chronic heart failure?
In stable chronic heart failure patients, within-person variation of NT-proBNP is relatively low (15.5-18.9%) and not influenced by renal function or weight, which is important for interpreting clinical trials and monitoring patients.
BACKGROUND: We investigated the variability of N-terminal probrain natriuretic peptide (NT-proBNP) and its relation to known confounding variables in patients with stable chronic heart failure who were on a stable optimized medication regimen. METHODS: At 4 sampling intervals (14-day, 1-month, 2-month, and 3-month) the results for NT-proBNP measurements and several clinical variables were measured in samples from 41 patients with chronic systolic dysfunction who met 21 prespecified criteria for stability. RESULTS: Mean within-person NT-proBNP variabilities expressed as percentage CV were 17.6%, 18.9%, 15.5%, and 16.2% at 14-day, 1-month, 2-month, and 3-month follow-up, respectively, and the corresponding reference change values were 34.6%, 52.5%, 43.1%, and 45.0%, respectively. Within-person variability of NT-proBNP was not found to be associated with renal function, weight, or waist circumference. Likewise, age, sex, baseline NT-proBNP, New York Heart Association functional class, and ejection fraction did not influence variability of NT-proBNP. The index of individuality ranged from 0.07-0.15 depending on the time interval between test results. CONCLUSIONS: Although other reported studies have revealed variations in the range of 80%, in this prespecified stable heart-failure population variation of NT-proBNP at 14-day, 1-month, 2-month, and 3-month follow-up was lower and was not related to renal function or weight. In view of the low index of individuality we observed, within-person variation is quite low compared to between-person variation. Consideration of these facts is important for the interpretation of clinical trials and the use of NT-proBNP in monitoring patients with heart failure.
Frankenstein et al. (Thu,) conducted a observational in Stable chronic heart failure (n=41). NT-proBNP variability was evaluated on Mean within-person NT-proBNP variability (percentage CV). Within-person NT-proBNP variability in stable heart failure patients was low (15.5% to 18.9% CV over 14 days to 3 months) and was not associated with renal function, weight, age, or sex.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: