Email updates

Keep up to date with the latest news and content from BMC Neurology and BioMed Central.

Open Access Highly Accessed Research article

Pesticide exposure and risk of Parkinson's disease: A family-based case-control study

Dana B Hancock1, Eden R Martin3, Gregory M Mayhew3, Jeffrey M Stajich1, Rita Jewett3, Mark A Stacy2, Burton L Scott2, Jeffery M Vance3 and William K Scott3*

Author Affiliations

1 Center for Human Genetics, Duke University Medical Center, Durham, NC, USA

2 Department of Medicine, Duke University Medical Center, Durham, NC, USA

3 Miami Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA

For all author emails, please log on.

BMC Neurology 2008, 8:6  doi:10.1186/1471-2377-8-6

Published: 28 March 2008

Abstract

Background

Pesticides and correlated lifestyle factors (e.g., exposure to well-water and farming) are repeatedly reported risk factors for Parkinson's disease (PD), but few family-based studies have examined these relationships.

Methods

Using 319 cases and 296 relative and other controls, associations of direct pesticide application, well-water consumption, and farming residences/occupations with PD were examined using generalized estimating equations while controlling for age-at-examination, sex, cigarette smoking, and caffeine consumption.

Results

Overall, individuals with PD were significantly more likely to report direct pesticide application than their unaffected relatives (odds ratio = 1.61; 95% confidence interval, 1.13–2.29). Frequency, duration, and cumulative exposure were also significantly associated with PD in a dose-response pattern (p ≤ 0.013). Associations of direct pesticide application did not vary by sex but were modified by family history of PD, as significant associations were restricted to individuals with no family history. When classifying pesticides by functional type, both insecticides and herbicides were found to significantly increase risk of PD. Two specific insecticide classes, organochlorines and organophosphorus compounds, were significantly associated with PD. Consuming well-water and living/working on a farm were not associated with PD.

Conclusion

These data corroborate positive associations of broadly defined pesticide exposure with PD in families, particularly for sporadic PD. These data also implicate a few specific classes of pesticides in PD and thus emphasize the need to consider a more narrow definition of pesticides in future studies.