Association between early-life farming exposure and Alzheimer's disease neuropathological burden.

BACKGROUND

Farming populations may face a disproportionate share of adverse exposures influencing Alzheimer's disease (AD), yet farming data are rarely connected to cohorts with characterized AD neuropathology. Whether early-life exposure is related to AD neuropathology is limited.

METHOD: Brain donors from two Alzheimer's Disease Research Centers (N = 1035; between 1986-2018) were included. US Census records were used to identify those with early-life farming exposure (birth to 17 years old) and examined alongside AD neuropathology assessments.

RESULT: Early-life farming exposure (≈ 17% of donors) was associated with 60% higher odds of AD neuropathological burden (odds ratio = 1.60, 95% confidence interval: 1.09-2.35) adjusting for age, sex, and year of death.

CONCLUSION

Findings suggest exposure to farming early in life is linked to increased levels of AD neuropathology. Deeper occupational and residential phenotyping is needed to identify the potential multiple, overlapping risk pathways, which may include cumulative and sensitive life stage exposure to chemical toxicants, hearing loss, and psychosocial hazards.