Table 7.
Odds ratios (OR) of amyotrophic lateral sclerosis for historical proximity to agricultural fields in tertiles of current exposurea
| Total | Emilia-Romagna | Sicliy | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| I | II | III | I | II | III | I | II | III | |||||||
| Total agricultural land | |||||||||||||||
| Cut off (%) | <28.1 | 28.1-77.8 | >77.8 | <30.8 | 30.8-78.4 | 78.4 | <11.2 | 11.2-74.7 | >74.7 | ||||||
| Cases/Controls | 339/1192 | 98/257 | 92/257 | 190/580 | 78/220 | 75/220 | 156/612 | 15/37 | 15/37 | ||||||
| OR (95% CI) | 1.00 | 1.27 | (0.96, 1.69) | 1.20 | (0.91, 1.60) | 1.00 | 1.09 | (0.80, 1.50) | 1.04 | (0.76, 1.42) | 1.00 | 1.51 | (0.81, 2.82) | 1.60 | (0.86, 2.99) |
| Vineyards | |||||||||||||||
| Cut off (%) | <12.4 | 12.4-25.1 | >25.1 | <12.4 | 12.4-24.0 | >24.0 | <0.1 | 0.1-99.9 | >99.9 | ||||||
| Cases/Controls | 507/1625 | 12/41 | 10/40 | 321/940 | 11/40 | 11/40 | 186/685 | 0/1 | 0/0 | ||||||
| OR (95% CI) | 1.00 | 0.79 | (0.40, 1.55) | 0.77 | (0.38, 1.56) | 1.00 | 0.76 | (0.38, 1.54) | 0.81 | (0.41, 1.61) | - | ||||
| All Orchards | |||||||||||||||
| Cut off (%) | <8.2 | 8.2-41.0 | >41.0 | <5.4 | 5.4-32.5 | >32.5 | <13.7 | 13.7-63.5 | >63.5 | ||||||
| Cases/Controls | 499/1624 | 14/41 | 16/41 | 332/985 | 8/17 | 3/18 | 168/640 | 6/23 | 12/23 | ||||||
| OR (95% CI) | 1.00 | 1.00 | (0.54, 1.88) | 1.41 | (0.78, 2.53) | 1.00 | 1.16 | (0.49, 2.74) | 0.50 | 1.00 | 0.91 | (0.36, 2.30) | 1.99 | (0.97, 4.07) | |
| Orchards (not citrus) | |||||||||||||||
| Cut off (%) | >6.8 | 6.8-36.6 | >36.6 | <6.8 | 6.8-34.8 | >34.8 | <13.7 | 13.7-99.9 | >99.9 | ||||||
| Cases/Controls | 518/1667 | 8/20 | 3/19 | 332/985 | 8/17 | 3/18 | 186/684 | 0/2 | 0/0 | ||||||
| OR (95% CI) | 1.00 | 1.01 | (0.44, 2.34) | 0.49 | (0.14, 1.67) | 1.00 | 1.16 | (0.49, 2.74) | 0.50 | (0.15, 1.74) | - | ||||
| Citrus orchards | |||||||||||||||
| Cut off (%) | <14.6 | 14.6-63.5 | >63.5 | ||||||||||||
| Cases/Controls | 168/643 | 6/22 | 12/21 | ||||||||||||
| OR (95% CI) | 1.00 | 0.94 | (0.37, 2.39) | 2.19 | (1.05, 4.54) | ||||||||||
| Arable and Veg. crops | |||||||||||||||
| Cut off (%) | <25.7 | 25.7-65.7 | >65.7 | <27.3 | 27.3-65.9 | >65.9 | <7.1 | 7.1-24.6 | >24.6 | ||||||
| Cases/Controls | 381/1288 | 67/210 | 81/208 | 196/613 | 66/203 | 81/204 | 186/677 | 0/5 | 0/4 | ||||||
| OR (95% CI) | 1.00 | 0.99 | (0.72, 1.37) | 1.21 | (0.88, 1.66) | 1.00 | 1.03 | (0.74, 1.42) | 1.26 | (0.92, 1.76) | - | ||||
| Arable crops | |||||||||||||||
| Cut off (%) | <27.3 | 27.3-65.9 | >65.9 | ||||||||||||
| Cases/Controls | 196/614 | 66/203 | 81/203 | ||||||||||||
| OR (95% CI) | 1.00 | 1.03 | (0.74, 1.42) | 1.27 | (0.92, 1.74) | ||||||||||
| Vegetables crops | |||||||||||||||
| Cut off (%) | <11.2 | 11.2-23.3 | >23.3 | ||||||||||||
| Cases/Controls | 342/1018 | 1/1 | 0/1 | ||||||||||||
| OR (95% CI) | 1.00 | 4.01 | (0.25, 64.11) | - | |||||||||||
| Olive groves | |||||||||||||||
| Cut off (%) | <8.5 | 8.5-18.6 | >18.6 | ||||||||||||
| Cases/Controls | 183/683 | 0/2 | 3/1 | ||||||||||||
| OR (95% CI) | 1.00 | - | 12.01 | (1.25, 115.45) | |||||||||||
aTertile cutpoints based on exposure of subjects having proximity to crops >0, with subjects having exposure = 0 included in the bottom tertile. OR computed using a conditional logistic regression model. Some estimates could not be computed because of too few exposed subjects