Intensive Care Unit, CHU Fattouma Bourguiba, Monastir, Tunisia.
Respirology. 2012 May;17(4):660-6. doi: 10.1111/j.1440-1843.2012.02153.x.
The aim of this study was to assess the performance of N-terminal proB-type natriuretic peptide (NT-proBNP) levels for the diagnosis of left ventricular dysfunction in patients with severe acute exacerbations of chronic obstructive pulmonary disease (COPD) and renal dysfunction.
NT-proBNP levels at admission were measured in consecutive patients admitted to two participating intensive care units with acute exacerbations of COPD. Left ventricular dysfunction was assessed on the basis of clinical and echocardiographic criteria. The performance of NT-proBNP levels was evaluated in patients with or without renal dysfunction.
Among the 120 patients included in the study, 70 had impaired renal function, defined as a glomerular filtration rate of <90 mL/min/1.73 m(2). NT-proBNP levels were inversely correlated with glomerular filtration rate (Spearman's correlation coefficient = -0.457, P < 0.001). Overall, left ventricular dysfunction was diagnosed in 58 patients (48.3%). Median NT-proBNP levels were significantly higher in these patients, irrespective of whether their renal function was normal (3313 (interquartile range (IQR) 4603) vs 337 (IQR 695) pg/mL, P < 0.001) or impaired (5692 (IQR 10714) vs 887 (IQR 1165) pg/mL, P < 0.001). The areas under the receiver operating characteristic curves were 0.87 and 0.78, respectively. The threshold NT-proBNP value with the highest diagnostic accuracy was greater in the setting of renal dysfunction (2000 pg/mL; sensitivity 71%, specificity 82%, compared with 1000 pg/mL in patients with normal renal function; sensitivity 94%, specificity 82%). Multivariate analysis showed that left ventricular dysfunction and glomerular filtration rate were independently associated with elevated NT-proBNP levels.
NT-proBNP remains an accurate biomarker for the diagnosis of left ventricular dysfunction associated with acute exacerbations of COPD. Threshold values of NT-proBNP were higher in patients with impaired renal function than in those with normal renal function.
本研究旨在评估 N 末端脑利钠肽前体（NT-proBNP）水平对伴有肾功能不全的慢性阻塞性肺疾病（COPD）急性加重患者左心室功能障碍的诊断价值。
连续入选入组于两个参与单位的 COPD 急性加重患者，于入院时测量 NT-proBNP 水平。左心室功能障碍基于临床和超声心动图标准进行评估。评估 NT-proBNP 水平在伴有或不伴有肾功能不全患者中的表现。
在纳入的 120 例患者中，70 例患者肾小球滤过率<90 mL/min/1.73 m2，存在肾功能不全。NT-proBNP 水平与肾小球滤过率呈负相关（Spearman 相关系数=-0.457，P<0.001）。总体上，58 例患者（48.3%）诊断为左心室功能障碍。这些患者的 NT-proBNP 中位数显著更高，无论其肾功能是否正常（3313（四分位距（IQR）：4603）比 337（IQR：695）pg/mL，P<0.001）或受损（5692（IQR：10714）比 887（IQR：1165）pg/mL，P<0.001）。受试者工作特征曲线下面积分别为 0.87 和 0.78。在肾功能不全的情况下，具有最高诊断准确性的 NT-proBNP 阈值更高（2000 pg/mL；敏感性 71%，特异性 82%，与肾功能正常患者的 1000 pg/mL 相比；敏感性 94%，特异性 82%）。多变量分析显示，左心室功能障碍和肾小球滤过率与 NT-proBNP 水平升高独立相关。
NT-proBNP 仍然是诊断与 COPD 急性加重相关的左心室功能障碍的准确生物标志物。在伴有肾功能不全的患者中，NT-proBNP 的阈值高于肾功能正常的患者。
