Thomas C, Hestermann U, Walther S, Pfueller U, Hack M, Oster P, Mundt C, Weisbrod M
Centre for Psychosocial Medicine, Department of General Psychiatry, University of Heidelberg, Germany.
J Neurol Neurosurg Psychiatry. 2008 Feb;79(2):119-25. doi: 10.1136/jnnp.2006.111732. Epub 2007 May 22.
Delirium in the elderly results in increased morbidity, mortality and functional decline. Delirium is underdiagnosed, particularly in dementia. To increase diagnostic accuracy, we investigated whether maintenance of activation assessed by EEG discriminates delirium in association with dementia (D+D) from dementia without delirium (DP) and cognitively unimpaired elderly subjects (CU).
Routine and quantitative EEG (rEEG/qEEG) with additional prolonged activation (3 min eyes open period) were evaluated in hospitalised elderly patients with acute geriatric disease. Patients were assigned post hoc to three comparable groups (D+D/DP/CU) by expert consensus based on DSM-IV criteria. Dementia diagnosis was confirmed using cognitive and functional tests and caregiver rating (IQCODE, Informed Questionnaire of Cognitive Decline in the Elderly).
While rEEG at rest showed low accuracy for a diagnosis of delirium, qEEG in DP and CU revealed a specific activation pattern of high significance found to be absent in the D+D group. Stepwise logistic regression confirmed that differentiation of D+D from DP was best resolved using activated upper alpha and delta power density which, compared with rEEG, enabled an 11% increase in diagnostic correctness to 83%, resulting in 67% sensitivity and 91% specificity. Among frail CU and D+D subjects, almost 90% were correctly classified.
Dementia associated with delirium can be discriminated reliably from dementia alone in a meaningful clinical setting. Thus EEG evaluation in chronic encephalopathy should be optimised by a simple activation task and spectral analysis, particularly in the elderly with dementia.
老年人谵妄会导致发病率、死亡率增加以及功能衰退。谵妄的诊断不足，尤其是在痴呆患者中。为提高诊断准确性，我们研究了通过脑电图（EEG）评估的激活维持情况是否能区分伴有痴呆的谵妄（D+D）与无谵妄的痴呆（DP）以及认知未受损的老年受试者（CU）。
对患有急性老年疾病的住院老年患者进行常规和定量脑电图（rEEG/qEEG）检查，并增加延长激活（睁眼3分钟）。根据DSM-IV标准，通过专家共识将患者事后分为三个可比组（D+D/DP/CU）。使用认知和功能测试以及照料者评分（IQCODE，老年人认知衰退知情问卷）来确诊痴呆。
虽然静息状态下的rEEG对谵妄诊断的准确性较低，但DP和CU组的qEEG显示出一种高度显著的特定激活模式，而D+D组中不存在这种模式。逐步逻辑回归证实，使用激活后的上α波和δ波功率密度能最好地区分D+D和DP，与rEEG相比，诊断正确性提高了11%，达到83%，敏感性为67%，特异性为91%。在体弱的CU和D+D受试者中，近90%被正确分类。
在有意义的临床环境中，可以可靠地区分伴有谵妄的痴呆与单纯的痴呆。因此，慢性脑病的脑电图评估应通过简单的激活任务和频谱分析进行优化，尤其是在患有痴呆的老年人中。
