A Michigan State University researcher is hoping to make a connection between pesticides, olfactory impairment and early symptoms of neurodegenerative diseases among aging farmers.
Honglei Chen, a professor of epidemiology whose research focuses on neurodegenerative diseases, will use a five-year, $5 million grant from the National Institutes for Health to investigate the role pesticides might play in olfactory impairment and their relevance to diseases such as Alzheimer's and Parkinson's.
"Our battle against Alzheimer's and Parkinson's may depend on early disease identification and intervention, and poor olfaction has been identified as an early warning for these diseases," Chen said. "This grant will allow us to connect the dots by identifying factors that contribute to poor olfaction among older adults and evaluating how this sensory deficit may progress to early stages of neurodegenerative diseases."
In preliminary analyses, researchers found a correlation between high pesticide exposure and self-reported poor sense of smell. In this project, researchers will objectively assess the olfaction of around 2,200 farmers using a standard smell test.
Using a scratch-and-sniff method, participants will need to correctly identify 12 common smells such as smoke, lemon, cinnamon or gasoline. Researchers will then conduct home visits of approximately 450 farmers to assess cognitive function and motor symptoms.
"We are trying to put everything into context with the ultimate goal of understanding the early stages of neurodegenerative diseases and factors involved," Chen said. "This project focuses on pesticides because earlier studies show their potential connections to neurodegenerative diseases. Now we want to define what role they play."
The study is being conducted using resources from the Agricultural Health Study and in partnership with researchers from Duke University, University of Chicago, Penn State University and NIH investigators of the Agricultural Health Study.