轻度认知障碍和阿尔茨海默病患者视网膜神经纤维层厚度的研究

Retinal nerve fiber layer thickness in the patients with mild cognitive impairment or Alzheimer's disease

目的了解轻度认知障碍(MCI)和阿尔茨海默病(AD)患者视网膜神经纤维层(RNFL)厚度的变化。设计病例-对照研究。研究对象北京海淀区4个社区和大兴区榆垡镇3个自然村50岁以上(包括50岁)的居民3122人中,排除确诊为青光眼等影响RNFL厚度疾病的患者后,剩余资料完整者共2511人,其中MCI 47例、AD 10例、认知正常者2454例;根据病例组的分布特征在认知正常者中随机抽取性别及年龄与病例组相匹配的正常对照167例作为正常对照组。方法用简易精神状态检查法(MMSE)初步测试受试者的认知功能,然后根据文盲组≤19分、小学组≤22分、中学及中学以上≤26分的分界标准,对MMSE异常人群再进一步进行日常生活能力量表(ADL)、临床痴呆评定量表(CDR)和Hachinski缺血指数量表评定,然后根据病史及神经心理量表评分筛出MCI及AD患者;用海德堡OCT仪检测所有受试者鼻侧、颞侧、上极及下极的视网膜神经纤维层(RNFL)厚度。对MCI组、AD组及正常对照组的RNFL厚度进行比较。主要指标视网膜神经纤维层(RNFL)厚度。结果 MCI组及AD组与正常对照组相比,在颞侧、上极及平均RNFL厚度上均明显变薄,组间有显著性差异(P均<0.05);MCI组与AD组相比,AD组各象限RNFL厚度均有变薄的趋势,但两组仅在颞侧的RNFL厚度有显著性差异(P<0.05)。结论与认知功能正常者相比,MCI及AD患者RNFL厚度在颞侧和上极明显变薄,且AD患者较MCI患者颞侧的RNFL厚度亦明显变薄,因此RNFL厚度可作为监测认知功能障碍的客观指标,颞侧RNFL厚度变化可能早期反映病情的进展。

Objective To investigate the variation of retinal nerve fiber layer （RNFL） thickness in patients with the mild cognitive impairment （MCI） and Alzheimer＇s disease （AD）. Design Case-control study. Participants 3122 residents over 50 years old（including 50 years old） who came from four communities of Haidian District and three natrual villages of Yufa town in Daxing District were inves- tigated, 2511 subjects who had complete data were include into the study and the subjects with glaucoma were removed. 47 subjects were diagnosed as MCI, 10 cases were AD and 2454 cases were normal cognition; 167 cases were randomly selected as normal control group from cognitively normal subjects according to distribution characteristics of the case group,whose sex and age were matched with the case group. Methods Initially, MMSE scales was used to test subjects＇ cognitive function; then, the subjects who were abnormal on MMSE with ADL, CDR and Hachinski ischemia index were evaluated according to the standard of illiterate group ≤ 19 scores, prima- ry-school group≤22 scores, middle school graduated above group ≤26 scores; eventually, the patients with MCI and AD were screened out according to medical history and cognitive function scores. The temporal, nasal, upper pole and lower pole RNFL thickness of all subjects were detected and measured with Heidelberg OCT instrument. The RNFL thickness between MCI group, AD group and normal control group were compared. Main Outcome Measures RNFL thickness. Results Compared with the normal control group, the RNFL thickness in the temporal side, upper pole and the average in MCI group and AD group was significantly thinner（all P〈0.05）. The RNFL thickness of every quadrant in AD group were thinning trend compared with MCI group, but there was significant difference only in temporal （P〈0.05）. Conclusion Compared with normal cognitive functions individuals,RNFL thickness in the temporal and upper polewas significant thinner in MCI and AD patients; RNFL thickness of the temporal quadrant in AD patients was thinner than MCI patients. So the RNFL thickness, especially in the temporal quadrant, might be used as early objective indicators for monitoring cognitivedysfunction.