Frankenstein Lutz, Remppis Andrew, Frankenstein Joerdis, Hess Georg, Zdunek Dietmar, Slottje Karen, Katus Hugo A, Zugck Christian
Department of Cardiology, Angiology, and Pulmonology; University of Heidelberg, Heidelberg, Germany.
Clin Chem. 2009 May;55(5):923-9. doi: 10.1373/clinchem.2008.112052. Epub 2009 Mar 19.
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.
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.
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.
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.
我们研究了在接受稳定优化药物治疗方案的稳定型慢性心力衰竭患者中，N 末端脑钠肽前体（NT-proBNP）的变异性及其与已知混杂变量的关系。
在 4 个采样间隔（14 天、1 个月、2 个月和 3 个月），对 41 例符合 21 项预先设定的稳定性标准的慢性收缩功能障碍患者的样本进行 NT-proBNP 测量结果及若干临床变量的检测。
在 14 天、1 个月、2 个月和 3 个月随访时，以 CV 百分比表示的个体内 NT-proBNP 变异性分别为 17.6%、18.9%、15.5%和 16.2%，相应的参考变化值分别为 34.6%、52.5%、43.1%和 45.0%。未发现 NT-proBNP 的个体内变异性与肾功能、体重或腰围相关。同样，年龄、性别、基线 NT-proBNP、纽约心脏协会功能分级和射血分数也不影响 NT-proBNP 的变异性。个体性指数根据检测结果之间的时间间隔在 0.07 - 0.15 之间。
尽管其他报道的研究显示变异性范围达 80%，但在这个预先设定的稳定心力衰竭人群中，14 天、1 个月、2 个月和 3 个月随访时 NT-proBNP 的变异性较低，且与肾功能或体重无关。鉴于我们观察到的低个体性指数，个体内变异与个体间变异相比相当低。考虑这些事实对于解释临床试验以及在监测心力衰竭患者中使用 NT-proBNP 很重要。
