The Study Of The Correlation Between Living Environment,Built Environment And Mild Cognitive Impairment Among Older Adults

Objectives:Many research addressing the relationship between environmental factors and cognitive function of the elderly,and a good environment can delay or even reduce the occurrence of Alzheimer’s disease,thus reducing the economic burden of family and society and improving the quality of life of the elderly.However,research on the correlation between environmental factors and cognitive function is still rare in China and requires in-depth research.Therefore,this study discusses the correlation between environmental factors(including living environment and built environment)and cognitive function and mild cognitive impairment in the elderly,in order to provide suggestions for the construction of elderly friendly communities in China and reduce or delay the occurrence of Alzheimer’s disease.Methods: Based on the Anhui Health and Longevity Survey(AHLS),this study adopted the method of multi-stage conceptual sampling,and selected Chuzhou(east),Lu ’an(west),Xuancheng(south)and Fuyang(north)in Anhui Province,selected 3-5 cities and rural communities in each city to conducted a questionnaire survey for the elderly aged60 years and above.The cognitive score of the elderly was measured by the mini mental State Scale(MMSE).According to the MMSE score and educational level,the participants were divided into cognitive normal group and with mild cognitive impairment(MCI),which were assigned as 0 and 1 respectively as the dependent variable.This study assessed the living environment of the elderly by asking them about their daily living conditions(including dust,noise and the access to recreational space).Based on the geographical location of the residence for the participants,the distance between the elderly’s residence and the nearest infrastructure(supermarkets,hospitals,restaurants and parks)and the proportion of green space and water area within the 800 m buffer zone of the residence were calculated to evaluate the built environment.This study establishes three basic regression models.Model 1 does not adjust the control variables.Model 2incorporates the Socio-demographic characteristicsbasics(including regions,urban and rural areas,gender,age,education level,marital status and income level)as the control variables.Model 3 is based on model 2,Further inclusion of lifestyle factors(including alcohol consumption,smoking,depressive status,overweight,sleep quality,and physical activity)as control variables.Epi Data3.1 was used to for data management,and SPSS24.0 software and Stata15.0 software were used to analyze the data.Chi-square test was used to compare the categorical variables,and the correlation between living environment and built environment and MCI was analyzed by multiple logistics regression method.Results: Basic information: The average age of the subjects was 71.0 years old,including2665 males(45.6%)and 2953 females(54.4%),with a slightly higher proportion of females.The results of stratified analysis according to different social and demographic characteristics showed that the prevalence rates of MCI were higher in females,rural residents,illiterates and those with annual income less than 6500 yuan,which were 60.6%,59.1%,58.0% and 71.6%,respectively.There were significant differences(p <0.05)between MCI patients and cognitively normal elderly people in areas such as location,alcohol consumption,smoking,depression,sleep status,and surrounding environment(accessibility,water,green space)within 800 meters.There was no significant difference in diabetes mellitus(p > 0.05).After stratifying by gender,the male participants who lived in a non-dusty environment had higher MMSE scores(β= 0.838,95% CI: 0.248,1.428,p adjusted =0.045)and had a lower risk of mild cognition impairment(MCI)(OR= 0.652,95% CI: 0.490,0.868,p adjusted = 0.027),and the male participants with no access to recreational space had lower MMSE scores(β=-1.125,95% CI:-1.548,-0.702,p adjusted<0.001)and had a higher risk of MCI(OR= 1.413,95% CI: 1.142,1.748,p adjusted =0.009).Compared with female participants who living far from the supermarket(Q1),the MMSE scores of the female participants who living near the supermarket significantly decreased(Q3: β=-0.750,95% CI:-1.266,-0.233,p adjusted =0.036;Q4:β=-1.184,95%CI:-1.745,-0.624,p adjusted <0.001).Conclusions: Living environment and built environment might have sex specific associations with cognitive function of elderly.Therefore,a scientific standard for agefriendly community environment construction which is suitable for Chinese context is needed.