Abstract:  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 investigated, 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, primary-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 pole was 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 cognitive dysfunction. (Ophthalmol CHN, 2014, 23: 231-234)

Key words: mild cognitive impairment, Alzheimer's disease, retinal nerve fiber layer thickness