Center for Quality of Aging, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.
Int Psychogeriatr. 2011 Sep;23(7):1175-81. doi: 10.1017/S1041610210002486. Epub 2011 Feb 4.
Delirium occurs frequently in the intensive care unit (ICU), but its pathophysiology is still unclear. Low levels of insulin-like growth factor 1 (IGF-1), a hormone with neuroprotective properties, have been associated with delirium in some non-ICU studies, but this relationship has not been examined in the ICU. We sought to test the hypothesis that low IGF-1 concentrations are associated with delirium during critical illness.
Mechanically ventilated medical ICU patients were prospectively enrolled, and blood was collected after enrollment for measurement of IGF-1 using radioimmunometric assay. Delirium and coma were identified daily using the Confusion Assessment Method for the ICU and the Richmond Agitation-Sedation Scale, respectively. The association between IGF-1 and delirium was evaluated with logistic regression. In addition, the association between IGF-1 and duration of normal mental state, measured as days alive without delirium or coma, was assessed using multiple linear regression.
Among 110 patients, the median age was 65 years (IQR, 52-75) and APACHE II was 27 (IQR, 22 -32). IGF-1 levels were not a risk factor for delirium on the day after IGF-1 measurement (p = 0.97), at which time 65% of the assessable patients were delirious. No significant association was found between IGF-1 levels and duration of normal mental state (p = 0.23).
This pilot study, the first to investigate IGF-1 and delirium in critically ill patients, found no association between IGF-1 and delirium. Future studies including serial measurements of IGF-1 and IGF-1 binding proteins are needed to determine whether this hormone has a role in delirium during critical illness.
谵妄在重症监护病房（ICU）中经常发生，但其病理生理学仍不清楚。一些非 ICU 研究表明，具有神经保护特性的胰岛素样生长因子 1（IGF-1）水平较低与谵妄有关，但尚未在 ICU 中进行过此项研究。我们试图验证这样一个假设，即在危重病期间，低 IGF-1 浓度与谵妄有关。
前瞻性纳入机械通气的内科 ICU 患者，入组后采集血液，使用放射免疫测定法测量 IGF-1。使用 ICU 意识模糊评估法和 Richmond 躁动-镇静量表每天分别评估谵妄和昏迷。使用逻辑回归评估 IGF-1 与谵妄的关系。此外，使用多元线性回归评估 IGF-1 与正常精神状态持续时间（定义为无谵妄或昏迷的存活天数）的关系。
在 110 例患者中，中位年龄为 65 岁（IQR，52-75），APACHE II 评分为 27（IQR，22-32）。IGF-1 水平不是 IGF-1 测量后第 1 天谵妄的危险因素（p = 0.97），此时 65%的可评估患者存在谵妄。IGF-1 水平与正常精神状态持续时间之间没有显著关联（p = 0.23）。
这项初步研究首次调查了 ICU 中患者的 IGF-1 与谵妄之间的关系，未发现 IGF-1 与谵妄之间存在关联。需要进行包括 IGF-1 和 IGF-1 结合蛋白的连续测量在内的未来研究，以确定这种激素在危重病期间谵妄中是否具有作用。
