van Hout M S E, Schmand B, Wekking E M, Deelman B G
Department of Psychology, Medical Spectrum Twente Hospital, PO Box 50000, NL-7500 KA Enschede, The Netherlands.
J Neurol Neurosurg Psychiatry. 2006 Mar;77(3):296-303. doi: 10.1136/jnnp.2004.047167.
Chronic toxic encephalopathy (CTE) caused by long term occupational exposure to organic solvents is still a controversial disorder. Neuropsychological testing is the cornerstone for diagnosing the syndrome, but can be negatively influenced by motivational problems. In this nationwide study, we investigated the neuropsychological functioning and psychological symptoms of a large group of patients with suspected CTE, and ruled out alternative explanations for their complaints, including suboptimal performance due to insufficient effort.
We studied participants with suspected CTE (n = 386) who were referred for further diagnosis to the Netherlands Centre of Occupational Diseases in the period 1998-2003 and who had completed the entire diagnostic protocol. Patients were excluded if there was the slightest suspicion that test performance had been negatively influenced by insufficient effort (n = 221), or if comprehensive assessment identified an alternative diagnosis (n = 80). Insufficient effort was defined by a combination of three indices. The neuropsychological test scores of the patient group (n = 85) were compared with those of a control group of building trade workers matched for sex, age, and educational level (n = 35).
The patient group had significantly more psychological complaints and performed significantly worse than the control group on tests of speed of information processing and memory and learning. However, only a small percentage of the patients had clearly abnormal scores for cognitive speed (9%) or memory (8%). Attention, verbal abilities, and constructional functions were not disturbed. Exposure duration and cognitive complaints were significantly correlated, whereas the correlation between exposure duration and neuropsychological domain scores was not significant.
Insufficient effort was present in a substantial part of the patient group. After minimising the likelihood that insufficient effort negatively influenced neuropsychological scores, we still found neuropsychological deficits in speed of cognitive processing and memory; however, these scores were clearly abnormal only in a minority of patients with suspected CTE. Screening instruments should focus on these domains.
长期职业性接触有机溶剂所致的慢性中毒性脑病（CTE）仍是一种存在争议的病症。神经心理学测试是诊断该综合征的基石，但可能会受到动机问题的负面影响。在这项全国性研究中，我们调查了一大群疑似CTE患者的神经心理功能和心理症状，并排除了对其主诉的其他解释，包括因努力不足导致的表现不佳。
我们研究了1998年至2003年期间被转介到荷兰职业病中心进行进一步诊断且完成了整个诊断方案的疑似CTE参与者（n = 386）。如果有丝毫怀疑测试表现受到努力不足的负面影响（n = 221），或者综合评估确定有其他诊断（n = 80），则将患者排除。努力不足由三个指标综合定义。将患者组（n = 85）的神经心理学测试分数与性别、年龄和教育水平相匹配的建筑行业工人对照组（n = 35）的分数进行比较。
患者组的心理主诉明显更多，在信息处理速度、记忆和学习测试中的表现明显比对照组差。然而，只有一小部分患者的认知速度（9%）或记忆（8%）得分明显异常。注意力、语言能力和构建功能未受干扰。接触时长与认知主诉显著相关，而接触时长与神经心理学领域分数之间的相关性不显著。
患者组中有相当一部分存在努力不足的情况。在将努力不足对神经心理学分数产生负面影响的可能性降至最低后，我们仍然发现认知处理速度和记忆方面存在神经心理学缺陷；然而，这些分数仅在少数疑似CTE患者中明显异常。筛查工具应关注这些领域。
