Devakonda Arun, George Liziamma, Raoof Suhail, Esan Adebayo, Saleh Anthony, Bernstein Larry H
Department of Medicine, Division of Pulmonary and Critical Care, New York Methodist Hospital, Brooklyn, NY 11215, USA.
Clin Biochem. 2008 Oct;41(14-15):1126-30. doi: 10.1016/j.clinbiochem.2008.06.016. Epub 2008 Jul 3.
A determination of serum Transthyretin (TTR, Prealbumin) level is an objective method of assessing protein catabolic loss of severely ill patients and numerous studies have shown that TTR levels correlate with patient outcomes of non-critically ill patients. We evaluated whether TTR level correlates with the prevalence of PEM in the ICU and evaluated serum TTR level as an indicator of the effectiveness of nutrition support and the prognosis in critically ill patients.
We studied PEM prevalence in 118 patients admitted to a community hospital's medical intensive care unit and the association between TTR, low albumin (ALB) concentration and high-risk disease (HRD), i.e., sepsis, inability to take in oral nutrients, etc. Serum TTR was measured on the day of admission, day 3 and day 7 of their ICU stay. APACHE II and SOFA score was assessed on the day of admission and the nutritional status and nutritional requirement was assessed for their entire ICU stay. Patients were divided into three groups based on initial TTR level and the outcome analysis was performed for APACHE II score, SOFA score, ICU length of stay, hospital length of stay, and mortality.
TTR showed excellent concordance with patients classified with PEM or at high malnutrition risk, and followed for 7 days, it is a measure of the metabolic burden. TTR levels decline from day 1 to day 7 in spite of providing nutritional support. Patients were classified in 3 categories with respect to the level of TTR: more than 170 mg/L, twenty-five patients (group 3); 100-170 mg/L, forty-eight patients (group 2); less than 100 mg/L, forty-five patients (group 1). TTR level correlated with ICU length of stay, hospital length of stay, and APACHE II score, and predicts mortality.
TTR identified patients at highest risk for metabolic losses associated with stress hypermetabolism as serum TTR levels did not respond early to nutrition support because of the delayed return to anabolic status. It is particularly helpful in removing interpretation bias, and it is an excellent measure of the systemic inflammatory response concurrent with a preexisting state of chronic inanition.
测定血清转甲状腺素蛋白（TTR，前白蛋白）水平是评估重症患者蛋白质分解代谢损失的一种客观方法，并且大量研究表明，TTR水平与非重症患者的预后相关。我们评估了TTR水平是否与重症监护病房（ICU）中蛋白质 - 能量营养不良（PEM）的患病率相关，并将血清TTR水平作为营养支持效果及重症患者预后的一项指标进行评估。
我们研究了一家社区医院内科重症监护病房收治的118例患者的PEM患病率，以及TTR、低白蛋白（ALB）浓度与高危疾病（HRD）（即脓毒症、无法经口摄入营养等）之间的关联。在患者入住ICU当天、入住第3天和第7天测定血清TTR。在入住当天评估急性生理与慢性健康状况评分系统（APACHE II）和序贯器官衰竭评估（SOFA）评分，并在患者整个ICU住院期间评估其营养状况和营养需求。根据初始TTR水平将患者分为三组，并对APACHE II评分、SOFA评分、ICU住院时长、住院总时长和死亡率进行结局分析。
TTR与被归类为患有PEM或处于高营养不良风险的患者具有良好的一致性，并且随访7天，它是代谢负担的一项指标。尽管提供了营养支持，但TTR水平从第1天到第7天仍会下降。根据TTR水平将患者分为3类：超过170mg/L，25例患者（第3组）；100 - 170mg/L，48例患者（第2组）；低于100mg/L，45例患者（第1组）。TTR水平与ICU住院时长、住院总时长和APACHE II评分相关，并可预测死亡率。
TTR可识别出与应激性高代谢相关的代谢损失风险最高的患者，因为血清TTR水平因恢复合成代谢状态延迟而未对营养支持做出早期反应。它在消除解释偏倚方面特别有帮助，并且是与预先存在的慢性营养不良状态并发的全身炎症反应的一项出色指标。
