Association of Metabolic Syndrome with the Development of Alzheimer’s Disease: A Systematic Review with Meta-analysis
Patricio Castro Suarez1, Claudia Cruzalegui Bazán1, Mario Chavez Hermosilla1
1Sociedad Científica de San Fernando, Universidad Nacional Mayor de San Marcos, Lima, Peru
Objective:
To conduct a systematic review and meta-analysis to evaluate the evidence related to the association between Metabolic Syndrome (MetS) and the development of Alzheimer’s Disease (AD).
Background:
Alzheimer's Disease is the main type of dementia worldwide and the role of risk factors implicated on its pathogenesis is vastly complex, identifying them is important to control those that are modifiable. Recent studies have shown that insulin resistance, which is a common characteristic present in MetS, could be implicated on AD development.
Design/Methods:
A systematic search was conducted in PubMed, Embase, Scopus, Web of Science and Google Scholar until September 2023. The NewCastle-Ottawa tool was used for risk of bias assessment. A meta-analysis with randomized effects model was calculated using the DerSimonian-Laird estimator to obtain the pooled effect measure of the outcome and a narrative synthesis, when this wasn't posible. GRADE criteria was used to evaluate the certainty of evidence.
Results:
Thirteen out of 416 articles were selected. With moderate certainty, the meta-analysis of the reported hazard ratios (HR) exhibited no association between MetS and AD (HR: 1.09; 95%CI: 1.07 - 1.11; I2= 18.57%). Narrative review of articles that calculated odds ratio (OR) showed association between both conditions, with moderate certainty; where all but one of them indicated that MetS was a risk factor, ranged from OR: 0.61 to OR: 11.48.
Conclusions:
We found that presence of MetS is not determinant for development of AD, but data available is not conclusive enough and potential effect modifiers might explain the significant risk found in certain populations. Further studies across different settings are required in order to clarify the interaction of MetS and other variables in the development of AD.