Association Of Selenium Levels In Blood With Frailty And Its Components In The Older Adults Aged 65 Years And Above In Nine Longevity Areas Of China

Objective:To understand the blood selenium level and frailty status of the elderly in 9areas of longevity in China,our study analyze the factors affecting frailty of the elderly and explore the correlation between trace element selenium and frailty and its internal components.In order to cope with the occurrence and development of frailty of the elderly,our team focus on the prevention and intervention management strategies of frailty of the elderly,and plan to provide theoretical support and intervention suggestions for the realization of health and longevity of the population.Methods:Using cross-sectional data from the 2017-2018 in Healthy Ageing and Biomarkers Cohort Study（HABCS）,the general demographic characteristics,lifestyle,behavior and dietary patterns of the elderly（65 years and above）in 9 long-lived areas of China were collected by our professional medical staff.A total of 2464 elderly people were included as research objects in this epidemiological investigation.Frailty Index（FI）was used to evaluate the frailty of the senior citizen in the geriatric field.FI≥0.25 was defined as frailty,and FI<0.25 was defined as non-frailty.The statistical software SAS programming was used to describe the frailty of the elderly in 9 areas of longevity.Chi-square test was used for univariate analysis of people with frailty.Multivariate Logistic regression model was used to analyze the relationship between selenium level and frailty and its internal components in the aged.Considering that the blood selenium in our study is a continuous variable,what might have a linear or non-linear relationship with frailty in the senior citizen.Our study aimed to explore the possible linear or non-linear correlation between blood selenium level and frailty by in the senior citizen using the restricted cubic spline function in the statistical model.Results:1.Among 2464 general elderly,the median blood selenium was 102.44μg/L,and the prevalence of frailty was 24.27%.The prevalence rate of frailty in≥100 years old was the highest（65.25%）.The prevalence of frailty in women（32.24%）was significantly higher than that in men（15.59%）.2.Multivariate Logistic regression analysis showed that after adjusting confounding factors,among demographic factors,age,gender,BMI,marital status and economic level could all be independent factors affecting frailty in the elderly,with statistical significance（P<0.05）.In the factors of life and behavior habits,drinking status and exercise were independent factors affecting frailty in the elderly,and the results were statistically significant（P<0.05）.Among the daily dietary characteristics,frequency of fruit consumption and frequency of vegetable consumption were both independent factors affecting frailty in the elderly,and the results were statistically significant（P<0.05）.3.The results of multivariate Logistic regression model analysis showed that after adjusting demographic factors,behavioral factors and dietary factors,the risk of frailty in group Q₂,Q₃and Q₄was reduced compared with group Q₁,and the OR（95%CI）values were 0.64（0.48～0.87）,0.71（0.52～0.96）and0.67（0.47～0.94）,respectively.According to the multivariate Logistic regression model fitted with Restricted cubic splines（RCS）function,there was a nonlinear exposure response relationship between blood selenium level and the risk of frailty in the elderly(P_nonlinearity=0.0448<0.05).Higher blood selenium levels were negatively associated with the risk of frailty.The higher the level of blood selenium exposure,the lower the risk of ADL disability,IADL disability,cognitive impairment,functional limitation,visual impairment,hearing impairment,and abnormal heart rate in the elderly.After adjusting for confounding factors,OR（95%CI）of abnormal heart rate was 0.53（0.36～0.79）in Q₂compared with Q₁.The OR（95%CI）values of ADL disability,IADL disability,cognitive impairment,functional limitation,visual impairment and hearing impairment in Q₄group were 0.61（0.41～0.87）,0.43（0.32～0.61）,0.39（0.26～0.58）,0.63（0.47～0.84）,0.62（0.43～0.89）and 0.47（0.36～0.63）,respectively.Conclusions:1.Based on a large sample of community population,this study found that the increase of blood selenium level can reduce the risk of frailty in the elderly.2.Increasing age,female,obesity,unaccompanied,poor,low alcohol consumption,no exercise,low intake of fruits and vegetables may be the risk factors for frailty in the elderly.3.The higher the blood selenium level,the lower the risk of ADL disability,IADL disability,cognitive impairment,functional limitation,hearing impairment,visual impairment,and abnormal heart rate in the elderly.These outcome suggests that trace element selenium might reduce the incidence of frailty by reducing the risk of ADL disability,IADL disability,impaired cognitive function,functional limitation,hearing impairment,visual impairment,and abnormal heart rate.4.It is recommended that appropriate amount of selenium supplement is appropriate for the elderly,urban elderly,malnourished,no spouse,no pension insurance,poor economic status,do not drink alcohol,fresh fruit and vegetable intake of the elderly group.