Parkinson's disease: A case‐control study of occupational and environmental risk factors

Abstract

We compared personal histories of 57 cases and 122 age-matched controls to identify possible environmental determinants of Parkinson's disease (PD). Odds ratios (OR) adjusted for sex, age, and smoking were computed using stepwise logistic regression. We found a statistically significant increased risk for working in orchards (OR = 3.69, p = 0.012, 95% CI = 1.34, 10.27) and a marginally significant increased risk associated with working in planer mills (OR = 4.11, p = 0.065, 95% CI = 0.91, 18.50). A Fisher's exact test of the association between PD development and (1) paraquat contact, and (2) postural tremor gave statistically significant probability estimates of 0.01 and 0.03, respectively. The relative risk of PD decreased with smoking, an inverse relationship supported by many studies.

Epidemiology and etiology of Parkinson’s disease: a review of the evidence

“…Whilst most studies found similar antibody levels in cases and controls, one study observed higher antibody levels for herpes simplex [538], while another study found lower antibody levels for herpes simplex, rubella and measles [539]. Similarly, studies that examined self-reported history of influenza [132,292,344] or other viral infections [142,411,540] generally reported no association with PD. A case-control study nested within the Harvard Alumni cohort, USA [541] found reduced PD risk associated with measles infection (OR 0.53, 95% CI 0.31-0.93) and another case-control study [411] found increased PD risk associated with diphtheria (OR 2.3, 95% CI 1.2-4.7) and croup (OR 4.1, 95% CI 1.1-16.1).…”

“…Of the 34 casecontrol studies that investigated the association between farming and PD, 7 reported an increased risk [290,293,298,303,321,322,344] with ORs that ranged between 1.3 and 5.2.…”

Paraquat and Parkinson's disease

“…In particular, Hertzman et al 17 published two reports, in 1990 and 1994. The 1990 study was based on a case-control sample identified in the Kootenay region, a rural mountainous area of British Colombia with a reportedly high PD prevalence.…”

Parkinson's disease and pesticides: a toxicological perspective

“…This led to speculation that paraquat also might be a potential dopamine neurotoxin [22,23]. Several epidemiological studies have reported a positive association between paraquat exposure and the development of PD [24][25][26], although these findings have not been replicated in a large cohort study. Laboratory studies have provided conflicting results.…”