Meta-analysis On The Relationship Between The Risk Of Alzheimer’s Disease And Waist Circumefrence

Objective：Study on the relativity between the risk of dementia and Alzheimer’sdisease and waist circumference which contributes to figuring out thereasonable control range of waist circumference to reduce risk of beingattacked by dementia.Process：According to retrieving longitudinal, prospective cohort studies fromPUBMED（1950-2012）, Embase（1947-2012） and CochraneLibrary（1800-2012）, the subject, who has the age above40, isnon-dementia at baseline. While the end point had always include AD andone of the predictive factors is waist circumference（WC）. Studies whichare accorded with the inclusive criteria can be divided into two categoriesin the main. One is doing research divided subject into two grades with astandard value, which for men is102cm while for women is88cm, nameddata of Research A. The other category is to divide waist circumferenceby quantile: that to arrange the date in order and the first25%of data isQ₁,25%⁵0%is Q₂,50%⁷5%is Q₃,and75%¹00%is Q₄, all of thisdata named the data of Research B. Extract compatible data for metaanalysis and do merging analysis through the research data using logarithm of HR and standard error of mean. Heterogeneity test is carriedout through I2statistic. If I2＜50%, which means there is no obviousheterogeneity, fixed effect model is applied Otherwise, random effectsmodel works. The final outcome is expressed by merged value of HR and95%CI. If HR＞1，the risk is higher than control group. On the contrary,HR<1, control group is the riskier one.Consequence：The results show that, taking102cm for male and88cm for femaleas standard, the AD risk of people who have higher waist circumferencereduced38%.The meta-analysis results through the data from Research Bshow that, there are three studies concerning risk of AD, asHR=0.94,95%CI（0.62-1.43），I2=17%. The results show that，setting thelowest/highest waist circumference value in quartile range in theresearch as Lowest/Highest WC group respectively, there is no obviousdifference in the risk of AD between of these two groups（HR=0.94）Conclusion：Taking102cm for male and88cm for female as standard，peoplewhose waist circumference is higher take a lower risk of AD than thelower waist circumference people.