A Study Of Mild Cognitive Impairment In Elderly People In Middle And Low Altitude Area

Objectives To study the prevalence and the revelant factors of mild cognitive impairment in middle and low altitude areas. To investegate the characteristics of cognitive impairment of MCI with a series of neuropsychological scales in the middle-aged and elderly at middle and low altitudes.Methods There were collected 800 participants in low altitude(the altitude of 178 meters above sea level), and 750 participants in middle altitude(the altitude of 2260 meters above sea level). Of the Participants aged 45 years and older were investigated by the method of cluster random sampling from September 1, 2013 to September 31, 2015. The average age was 63.42±11.61 years old. Participants come from the Han nationality and living in local urban residents more than 10 years. The MCI questionnaire, Alzheimer’s Disease Assessment Scale-Cognitive section(ADAS-Cog), Mini-Mental State Examination(MMSE), clock-drawing test(CDT) and other neuropsychological scale were used to access the intellectual ability in these participants.Results 1. This study effective investigated a total of 1537 people, 215(13.99%) people met the diagnostic standard of MCI. At low altitude, 792 participants were collected, 95(11.99%) participants conform to the standard of MCI; Middle altitude area, 745 participants were collected, 120(16.11%) people met the MCI levels. Compared of the prevalence of MCI, significant difference was found between the middle and low altitude(P<0.05). 2. The results of the Logistic regression showed that factors significantly associated with MCI were age, education, altitude with the OR value(95% confidence interval) of 2.445(2.064~2.897),0.411(0.345~0.489)and 2.084(1.502~2.892), respectively. 3. Comparison between the MCI group and the normal group in the different altitudes, there were significant differences in the total score of ADAS-Cog, MMSE and CDT(P<0.01). Compared of MMSE and ADAS-Cog items, the difference was statistical on word recognition, word recalling, ability of calculation and short-term memory in the same group at different altitudes(P<0.05).Conclusions 1. The prevalence rate of MCI in middle altitude was higher than that of low altitude. 2. The seniors, the lower education, the higher altitude were the risk factors of MCI. 3. Three kinds of neuropsychological scales that MMSE, ADAS-Cog and CDT can be used for comprehensive evaluation of cognitive function in patients with MCI. 4. In different altitude regions,the most obvious cognitive impairment of MCI was in memories, ability of calculation, attention and short-term memory; but ability of orientation, drawing, and verbal ability were no obvious change.