Investigating environmental risk factors of dementia Open Access

Reynolds, Tylor (Spring 2020)

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Background: Dementia is a neurodegenerative disease that can commonly associated with cognitive decline and impacts approximately 1 in 10 individuals over the age of 65. There are many known environmental and genetic factors that potentially contribute to the development of dementia. Objectives: To examine environmental factors of dementia and determine if the extent of interaction between smoking, exposure to lead, and exposure to organochlorine insecticides. Methods: Data was collected from 100 participants over 65 years old from the 2013-2014 NHANES public dataset and analyzed in SAS. Logistic regression models were constructed to determine if smoking, lead exposure or exposure to DDT was correlated with lower signs of cognitive functioning. A multivariate model using environmental exposures was also constructed and analyzed to assess potential interaction. Results: Elevated levels of blood lead and DDT were correlated with a lower cognitive score which could indicate that these variables were promoting cognitive decline. Analysis revealed no significant relationship between serum cotinine levels and cognitive scores. Discussion: More investigation should be conducted regarding potential interactions between environmental and genetic factors of dementia. Smoking has been linked to dementia and cognitive decline in previous studies, however this data revealed no such relationship.

Table of Contents

Introduction 1

Literature Review 2

Effects of smoking on cognitive decline 3

Lead exposure effects on cognitive decline 4

Effects of pesticide exposure on cognitive impairment 5

Methods 5

Results 7

Figures 9-15

Discussion 16

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