Department of Neurology, National Institute of Mental Health and Neurosciences, Bangalore, India.
Eur J Neurol. 2014 Jun;21(6):874-83. doi: 10.1111/ene.12399. Epub 2014 Mar 11.
Impairment of cognitive functions occurs in essential tremor (ET) although the mechanism is largely unknown. A possible association between cognitive performance and brain atrophy in ET patients was examined using neuropsychological tests and voxel-based morphometry (VBM).
Twenty-five patients with ET and 25 matched healthy controls were evaluated. ET was diagnosed using the National Institutes of Health collaborative genetic criteria. Severity of tremor was assessed using the Fahn-Tolosa-Marin (FTM) tremor rating scale. Subjects were assessed using a structured neuropsychological battery. Brain images were acquired using a 3T magnetic resonance imaging scanner. VBM analysis was performed using Statistical Parametric Mapping 8.
The age of the patients was 45.0 ± 10.7 years and of controls 45.4 ± 10.7 years. Tremor duration was 9.84 ± 6.63 years and total FTM score was 37.34 ± 17.67. Patients were divided into two groups: ETCI with cognitive impairment (three or more abnormal neuropsychological tests, 1.5 standard deviation criterion) and ETNCI without cognitive impairment. Compared with controls, the ETCI group had significantly impaired performance in neuropsychological tests. One-way analysis of variance was performed between the three groups (ETCI, ETNCI, controls) followed by the two-sample t test. Compared with controls, grey matter volume (GMV) loss was observed in ETCI in the cerebellum (anterior and posterior lobes) and medial frontal gyrus. GMV loss was observed in ETCI compared with ETNCI in the medial frontal gyrus, post central gyrus, anterior cingulate and insula. Impairment in neuropsychological tests significantly correlated with GMV of the medial frontal gyrus, superior parietal lobe, middle temporal gyrus, occipital lobe, lentiform nucleus, insular and cingulate cortices and cerebellum posterior lobe in ETCI.
A correlation between neurocognitive deficits in ETCI and GMV was observed suggesting that grey matter atrophy appears to be a correlate of cognitive impairment in ET.
尽管机制尚不清楚，但原发性震颤（ET）患者仍会出现认知功能障碍。本研究通过神经心理学测试和基于体素的形态计量学（VBM）检查，探讨了 ET 患者认知功能与脑萎缩之间的可能关联。
共纳入 25 例 ET 患者和 25 例匹配的健康对照者。采用美国国立卫生研究院合作遗传标准诊断 ET，采用 Fahn-Tolosa-Marin（FTM）震颤评定量表评估震颤严重程度。所有受试者均接受了结构化神经心理学测试，采集了脑图像，并使用 3T 磁共振成像扫描仪进行 VBM 分析。
患者年龄为 45.0±10.7 岁，对照组为 45.4±10.7 岁。震颤持续时间为 9.84±6.63 年，总 FTM 评分为 37.34±17.67。根据是否存在认知障碍，将患者分为 ETCI 组（认知障碍，三个或更多神经心理学测试异常，采用 1.5 个标准差标准）和 ETNCI 组（无认知障碍）。与对照组相比，ETCI 组神经心理学测试表现明显受损。对 ETCI、ETNCI 和对照组三组进行单因素方差分析，然后进行两样本 t 检验。与对照组相比，ETCI 患者的小脑（前叶和后叶）和内侧前额叶灰质体积（GMV）减少，与 ETNCI 相比，ETCI 患者的内侧前额叶、中央后回、扣带回和岛叶 GMV 减少。神经心理学测试的损害与 ETCI 患者的内侧前额叶、顶叶上回、颞中回、枕叶、豆状核、岛叶和扣带回皮质及小脑后叶的 GMV 显著相关。
ETCI 患者的神经认知缺陷与 GMV 之间存在相关性，提示灰质萎缩可能是 ET 患者认知障碍的一个相关因素。
