Get Newsletter
AlzRisk Risk Factor Literature Search Strategy and Results

Risk Factor: Obesity
Risk Factor Type: Behavior, Metabolic
Current Understanding:
The tables below present a number of studies whose results, taken collectively, provide evidence suggesting that obesity may be associated with AD and total dementia. Many studies indicate that midlife obesity is associated with elevated risk of AD and dementia. Studies of adiposity in late-life, however, have found an inverse association, with higher risk for AD and dementia in underweight individuals and a reduced risk in obese participants. Much or all of the latter association could be explained by reverse causation, complex survival issues, and limitations in exposure measures. These results are consistent with results from related studies on adiposity and cognitive decline and from neuroimaging studies. However, it is still unclear whether there is a critical age at which obesity has a stronger influence on the development of AD and dementia, and whether the association is with overall adiposity or central adiposity. Thus, studies with longer follow-up times that include measures of both types of adiposity are needed to better understand this association. Despite these uncertainties, however, the association of obesity with AD and dementia provides an additional reason to maintain a healthy weight throughout life. For a more detailed interpretation of study findings and putative mechanisms, please view the Discussion.
Last Search Completed: 08 September 2012 - Last content updated on 19 Nov 2012.

Risk Factor Overview


We searched MEDLINE (via PubMed) and EMBASE for peer-reviewed articles reporting on the association between obesity and Alzheimer’s disease (AD) incidence in cohort or nested case-control studies. The search returned over one thousand unique citations that, after title and abstract review against our inclusion criteria, were narrowed down to 40 citations for full-text review. We further narrowed these down to 19 papers, which fully met criteria for inclusion in our summary tables. Please see our methods section for more detail on our general systematic review methods.

Search & Review Flowchart
Search Strategy

Search Strategy Flowchart

Search Strategy

Using our systematic review methods, we developed a strategy to search MEDLINE (using PubMed) and EMBASE.

Search Strategy Table