Table 3

Cumulative exposure to pesticides, specific subclasses and endotoxin and Parkinson disease risk: job-exposure matrix (JEM) approach

Cases
n (%)
Controls
n (%)
Crude
OR (95% CI)
Model 1*
OR (95% CI)
Model 2†
OR (95% CI)
Pesticides‡
 Never358 (80.6)709 (80.9)111
 1–1926 (5.9)56 (6.4)0.92 (0.57 to 1.48)0.91 (0.55 to 1.52)0.90 (0.52 to 1.56)
 20–3222 (5.0)56 (6.4)0.77 (0.46 to 1.30)0.74 (0.43 to 1.27)0.75 (0.42 to 1.36)
 33–21638 (8.6)55 (6.3)1.36 (0.89 to 2.09)1.28 (0.79 to 2.10)1.56 (0.86 to 2.83)
Insecticides‡
 Never377 (84.9)753 (86.0)111
 1–2022 (5.0)46 (5.3)0.95 (0.56 to 1.61)1.05 (0.60 to 1.84)1.10 (0.60 to 2.03)
 21–3616 (3.6)38 (4.3)0.85 (0.47 to 1.55)0.77 (0.40 to 1.47)0.83 (0.42 to 1.66)
 37–21629 (6.5)39 (4.5)1.48 (0.90 to 2.41)1.46 (0.84 to 2.53)1.79 (0.95 to 3.37)
Herbicides‡
 Never384 (86.5)767 (87.6)111
 1–616 (3.6)37 (4.2)0.85 (0.46 to 1.58)0.97 (0.51 to 1.85)1.00 (0.51 to 1.97)
 7–2323 (5.2)39 (4.5)1.19 (0.70 to 2.03)1.16 (0.66 to 2.04)1.30 (0.70 to 2.39)
 24–16821 (4.7)33 (3.8)1.26 (0.71 to 2.24)1.13 (0.59 to 2.15)1.25 (0.62 to 2.53)
Fungicides‡
 Never376 (84.7)746 (85.2)111
 1–719 (4.3)54 (6.2)0.70 (0.41 to 1.19)0.67 (0.38 to 1.18)0.64 (0.35 to 1.17)
 8–2522 (5.0)34 (3.9)1.33 (0.75 to 3.37)1.35 (0.73 to 2.50)1.41 (0.74 to 2.71)
 26–16827 (6.1)42 (4.8)1.26 (0.76 to 2.07)1.12 (0.65 to 1.93)1.24 (0.69 to 2.23)
Endotoxin‡
 Never275 (61.9)511 (58.3)11
 1–763 (14.2)128 (14.6)0.90 (0.64 to 1.27)1.09 (0.76 to 1.57)1.18 (0.78 to 1.79)
 8–2146 (10.4)117 (13.4)0.74 (0.51 to 1.07)0.79 (0.52 to 1.18)0.76 (0.48 to 1.18)
 22–24460 (13.5)120 (13.7)0.93 (0.67 to 1.30)0.95 (0.64 to 1.40)0.83 (0.51 to 1.34)
  • *The first adjusted model includes cigarette smoking (5 categories), coffee consumption (4 categories) and occupational skill and status (4 categories). Since information on coffee consumption was missing for one control, this participant was excluded from adjusted analyses.

  • †Additionally mutually adjusted: pesticide exposures to endotoxin and vice versa.

  • ‡Conditional logistic regression analyses of pesticide and endotoxin exposure as assessed by the JEM approach. Cumulative exposures were estimated by multiplying the JEM assigned exposures (0 for no, 1 for low and 4 for high exposure) with years worked in a job, summed across all jobs of a participant's occupational history from 1955. The JEM score was set to 0 for exposure to pesticides, insecticides, herbicides or fungicides if the participant reported that those were not applied. The exposed were divided based on the tertiles of the exposure distribution among the controls.