Pesticide exposure and cognitive function: Results from the Hellenic Longitudinal Investigation of Aging and Diet (HELIAD)

Abstract

Background: Results from studies to date, regarding the role of chronic pesticide exposure on cognitive function remain contradictory.

Objective: To investigate the relationship between self-reported pesticide exposure and cognitive function.

Methods: Data from a population-based cohort study of older adults (HEllenic Longitudinal Investigation of Aging and Diet) in Greece was used. Pesticide exposure classification was based on 1) living in areas that were being sprayed; 2) application of spray insecticides/pesticides in their gardens; and 3) occupational application of sprays. Associations between z-scores of cognitive performance and self-reported pesticide exposure were examined with linear regression analyses. Adjusted models were applied, for all analyses.

Results: Non-demented individuals who reported that they had been living in areas near sprayed fields, had poorer neuropsychological performance, compared to those who had never lived in such areas. Sub-analyses revealed poorer performance in language, executive and visual-spatial functioning, and attention. These associations remained after a sensitivity analysis excluding subjects with mild cognitive impairment.

Conclusion: Self-reported exposure to pesticides was negatively associated with cognitive performance.

Keywords: Alzheimer's disease; Cognitive function; Dementia; Environmental risk factors; Self-reported pesticide exposure.