Department of Anesthesiology & Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland.
Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
Anesthesiology. 2022 Sep 1;137(3):303-314. doi: 10.1097/ALN.0000000000004327.
Neurofilament light is a marker of neuronal injury and can be measured in blood. Postoperative increases in neurofilament light have been associated with delirium after noncardiac surgery. However, few studies have examined the association of neurofilament light changes with postdischarge cognition in cardiac surgery patients, who are at highest risk for neuronal injury and cognitive decline. The authors hypothesized that increased neurofilament light (both baseline and change) would be associated with worse neuropsychological status up to 1 yr after cardiac surgery.
This observational study was nested in a trial of cardiac surgery patients, in which blood pressure during bypass was targeted using cerebral autoregulation monitoring. Plasma concentrations of neurofilament light were measured at baseline and postoperative day 1. Neuropsychological testing was performed at baseline, 1 month after surgery, and 1 yr after surgery. Primary outcomes were baseline and change from baseline in a composite z-score of all cognitive tests.
Among 167 patients, cognitive outcomes were available in 80% (134 of 167) and 61% (102 of 167) at 1 month and 1 yr after surgery, respectively. The median baseline concentration of neurofilament light was 18.2 pg/ml (interquartile range, 13.4 to 28.1), and on postoperative day 1 was 28.5 pg/ml (interquartile range, 19.3 to 45.0). Higher baseline log neurofilament light was associated with worse baseline cognitive z-score (adjusted slope, -0.60; 95% CI, -0.90 to -0.30; P < 0.001), no change in z-score from baseline to 1 month (0.11; 95% CI, -0.19 to 0.41; P = 0.475), and improvement in z-score from baseline to 1 yr (0.56; 95% CI, 0.31 to 0.81; P < 0.001). Whereas some patients had an improvement in cognition at 1 yr and others a decline, an increase in neurofilament light from baseline to postoperative day 1 was associated with a greater decline in cognition at 1 yr.
Higher baseline neurofilament light concentration was associated with worse baseline cognition but improvement in cognition at 1 yr. A postoperative increase in neurofilament light was associated with a greater cognitive decline at 1 yr.
神经丝轻链是神经元损伤的标志物，可在血液中测量。非心脏手术后，神经丝轻链的术后增加与术后谵妄有关。然而，很少有研究检查神经丝轻链变化与心脏手术后患者出院后认知的关系，这些患者发生神经元损伤和认知能力下降的风险最高。作者假设，基线和变化后的神经丝轻链增加（基线和变化）与心脏手术后 1 年的神经心理状态恶化有关。
本观察性研究嵌套在一项心脏手术患者的试验中，该试验中使用脑自动调节监测来靶向旁路期间的血压。在基线和术后第 1 天测量神经丝轻链的血浆浓度。在基线、术后 1 个月和术后 1 年进行神经心理学测试。主要结局是所有认知测试综合 z 评分的基线和从基线的变化。
在 167 例患者中，分别有 80%（134/167）和 61%（102/167）在术后 1 个月和 1 年时可获得认知结果。神经丝轻链的中位基线浓度为 18.2pg/ml（四分位距，13.4 至 28.1），术后第 1 天为 28.5pg/ml（四分位距，19.3 至 45.0）。较高的基线对数神经丝轻链与较差的基线认知 z 评分相关（调整斜率，-0.60；95%CI，-0.90 至-0.30；P<0.001），从基线到 1 个月的 z 评分无变化（0.11；95%CI，-0.19 至 0.41；P=0.475），从基线到 1 年的 z 评分改善（0.56；95%CI，0.31 至 0.81；P<0.001）。尽管一些患者在 1 年内认知能力提高，而另一些患者认知能力下降，但从基线到术后第 1 天的神经丝轻链增加与 1 年内认知能力下降更大有关。
较高的基线神经丝轻链浓度与较差的基线认知能力相关，但在 1 年内认知能力有所提高。术后神经丝轻链的增加与 1 年内认知能力的更大下降有关。
