P300检测对无症状性脑梗死合并抑郁患者认知功能的评估价值

背景:无症状性脑梗死合并抑郁患经常合并认知功能损害,目前尚无可靠的客观测评方法对其进行评估。目的:探讨P300检测对于评定无症状性脑梗死合并抑郁患者认知功能障碍的价值。设计:标准对照。单位:西安市中心医院、西安交通大学第二医院神经内科。对象:病例来源于2002-01/2003-05西安交通大学第二医院神经内科门诊的无症状性脑梗死患者38例。其中就诊主诉头晕10例,注意力不集中11例,头痛8例,肢体麻木5例,晕厥4例。经CT检出26例,经MRI检出12例。男20例,女18例,年龄45-63岁,平均年龄(57.3±5.1)岁。方法:采用汉密尔顿抑郁量表17项版本测定患者有无抑郁状态,总分52分,评分≥9分为抑郁状态,分值越高提示抑郁程度越重。由经过专门培训的神经科医师对患者进行评估,一致性较好(Kappa0.86-0.91).在安静的电生理屏蔽室内对患者进行P300检测,测试工具为MY70型诱发电位仪进行听觉事件相关电位检测,受试者平卧于检查床上,安静放松、闭目、注意力集中,要求受试者明确分辩出两种不同频率的刺激音响,当听到靶刺激音响时默记次数。先进行实验性检查,待其掌握后进行正式检查。以其获得良好的重复性。由专人对所有受试者行简易精神状态检查法检查患者认知功能缺损情况,总分30分,分值越小认知功能缺损越重,按受教育时间定分界值(文盲17分,小学20分,中学及以上24分)。主要观察指标:简易精神状态检查法评定分值,P300潜伏期及波幅。结果:38例患者全部完成实验,均进入结果分析。①汉密顿抑郁量表测定结果:符合抑郁表现的抑郁组18例(占47%),无抑郁表现的非抑郁组20例(占53%)。②无症状性脑梗死合并与未合并抑郁患者P300指标及简易精神状态评分比较:与未合并抑郁患者比较,合并抑郁患者P300潜伏期明显延长,P300波幅及简易精神状态评分均明显降低,两组比较差异有显著性(383.3±31.1,347.2±37.3),(5.6±0.7,9.9±1.6),(15.2±1.1,20.5±2.7),(P<0.01)]。③P300指标与简易精神状态评分直线相关分析:无症状性脑梗死合并抑郁患者P300潜伏期与简易精神状态评分呈显著负相关(r=-0.549,P<0.05),P300波幅与简易精神状态评分呈显著正相关(r=0.525,P<0.05)。而未合并抑郁患者简易精神状态评分与P300潜伏期、波幅均无显著相关性(r=-0.349-0.065,P>0.05)。结论:无症状性脑梗死在并发抑郁和认知功能损害方面可能具有共同的病理生理基础,P300检测可作为辅助评定无症状性脑梗死合并抑郁患者认知功能的可靠手段。

Value of P300 detection in evaluating cognitive impairment of patients with silent cerebral infarction and depression

BACKGROUND: Cognitive impairments are often accompanied in patients with silent cerebral infarction (SCI) and depression, and there is still no reliable objective assessing method for the evaluation.OBJECTIVE: The purpose of this study was to probe into the value of auditory P300 in detecting the cognitive impairment in SCI patients with depression.DESIGN: A golden standard control study.SETTING: Department of Neurology, Xi 'an Central Hospital; Department of Neurology, the Second Hospital of Xi' an Jiao Tong University.PARTICIPANTS: Thirty-eight SCI patients were selected from the Outpatient Department of Neurology, the Second Hospital of Xi' an Jiao Tong University between January 2002 to May 2003, including 10 got dizziness,11 got poor concentration, 8 got headache, 5 got numbness of extremities and 4 got syncope. Among them, 26 were detected by CT and 12 by MRI.The patients'aged 45 to 63 years with mean age of (57.3±5.1) years, including 20 males and 18 females.METHODS: The existence of depressive symptoms was measured with the 17-item Hamilton depression scale (HAMD). In this scale, the total score ranged from 0 to 52, with higher score indicating more severe depressive symptoms, and the patient was considered as having depression if the HAMD score was ≥ 9. HAMD tests were administered by two psychiatrists,who were experienced in psychiatric disorders in stroke and other somatic diseases, and the two psychiatrists had a better coincidence (Kappa=0.86 -0.91). The auditory event related potential was detected with MYTO serial cerebra induced potential meter, while lying in a bed placed in a sound-attenuated room. Auditory stimuli were delivered binaurally through headphones. The subject was required to distinguish between the tones by noting the occurrence of the target and not to respond to the standard. All patients underwent a routine experimental test at first, and then a normal test was performed to obtain a better coincidence. Mini-mental state examination (MMSE) was conducted for the 38 patients by specialized training neurologist to assess the cognitive impairment, in which the total score ranged from 0 to 30, with lower score indicating greater impairment. The criteria of intellectual deterioration was defined on the basis of educational level:MMSE score of 17 for illiterate, 20 for primary school and 24 for middle school and above.MAIN OUTCOME MEASURES: The score of MMSE, latent period of P300 wave and amplitude of P300 wave were mainly observed.RESULTS: All the 38 cases were involved in the final statistical analyhave depressive symptoms (47%, depression group) and 20 had no depresindexes and score of MMSE between the SCI patients with and without depression: As compared with the SCI patients without depression, the P300 latent period was obviously prolonged, the P300 amplitude and MMSE score were markedly decreased in the SCI patients with depression (383.3±31.1), (347.2±37.3) ms; (5.6±0.7), (9.9±1.6) μV; (15.2±1.1),and P300 indexes: In the SCI patients with depression, the P300 latent period had significant negative correlation with the MMSE score (r=-0.549, P ＜ 0.05), the P300 amplitude had significant positive correlation with the MMSE score (r =0.525, P ＜ 0.05). However, there was no correlation between the latent period and amplitude of P300 and the MMSE score in the SCI patients without depression (r=-0.349 to 0.065, P ＞ 0.05).CONCLUSION: Depression and cognitive impairments may have the same pathophysiological basis in SCI patients. P300 can be used as a referential and objective method to analyze the cognitive function in SCI patients with depression.