Type 2 Diabetes Mellitus and Alzheimer’s Disease: Overlapping Biologic Mechanisms and Environmental Risk Factors
Purpose of Review
A number of studies over the past two decades have suggested that type 2 diabetes mellitus (T2DM) patients are at an increased risk of Alzheimer’s disease (AD). Several common molecular pathways to cellular and metabolic dysfunction have been implicated in the etiology of both diseases. Here, we review the emerging evidence from observational studies that investigate the relationship between T2DM and AD, and of shared environmental risk factors, specifically air pollution and pesticides, associated with both chronic disorders.
Particulate matter and traffic-related air pollution have been widely associated with T2DM, and multiple studies have associated exposures with AD or cognitive function. Organochlorine (OC) and organophosphate (OP) pesticides have been associated with T2DM in multiple independent populations. Two populations have observed increased risks for OC and OP exposures and AD. Other studies, limited in exposure assessment, have reported increased risk of AD with any pesticide exposure assessments.
This may suggest shared pathogenic pathways between environmental risk factors, T2DM, and AD. Research focusing on exposures related to both T2DM and AD could provide new disease insights on shared mechanisms and help shape innovative preventative measures and policy decisions.
KeywordsType 2 diabetes mellitus Alzheimer’s disease Environment Air pollution Pesticides
Parts per billion
This work was supported by the National Institute of Environmental Health Sciences (F32-ES028087 (KP), 2R01-ES010544 (BR), R01-ES023451 (BR, MJ).
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no conflict of interest.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
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