Table 3.
Adjusted ORs (95% CIs)a for glioma and meningioma in relation to categorical indicators of cumulative occupational ELF-MF exposure in three separate exposure time windows, 1–4, 5–9, and 10+ years prior to the date of diagnosis/reference date, INTEROCC study, 2000–2004, Australia, Canada, France, Germany, Israel, New Zealand, and United Kingdom
| Exposure Metric | Glioma | Meningioma | ||||
|---|---|---|---|---|---|---|
| Cumulative Exposure (μT-years) | Cases | Controls | OR 95% CIa | Cases | Controls | OR 95% CIa |
| 1–4 Years | ||||||
| < 0.34 | 332 | 1,115 | 1.00 (ref) | 315 | 1,054 | 1.00 (ref) |
| 0.34–< 0.46 | 338 | 1,012 | 1.19 (1.00, 1.43) | 301 | 970 | 1.00 (0.83, 1.21) |
| 0.46–< 0.58 | 432 | 1,140 | 1.42 (1.19, 1.69) | 350 | 1,093 | 1.12 (0.93, 1.34) |
| 0.58–<0.80 | 297 | 632 | 1.54 (1.27, 1.88) | 210 | 593 | 1.30 (1.05, 1.62) |
| 0.80+ | 237 | 439 | 1.67 (1.36, 2.07) | 142 | 420 | 1.23 (0.97, 1.57) |
| p-value trend | <0.0001 | 0.02 | ||||
| 5–9 Years | ||||||
| < 0.45 | 358 | 1,112 | 1.00 (ref) | 367 | 1,057 | 1.00 (ref) |
| 0.45–< 0.59 | 391 | 1,126 | 1.12 (0.95, 1.33) | 391 | 1,075 | 1.00 (0.84, 1.20) |
| 0.59–< 0.77 | 491 | 1,268 | 1.22 (1.03, 1.43) | 398 | 1,228 | 1.03 (0.86, 1.22) |
| 0.77–<1.07 | 263 | 671 | 1.09 (0.89, 1.32) | 185 | 636 | 0.97 (0.78, 1.20) |
| 1.07+ | 204 | 447 | 1.19 (0.96, 1.47) | 117 | 423 | 0.88 (0.68, 1.13) |
| p-value trend | 0.20 | 0.31 | ||||
| 10+ Years | ||||||
| < 1.38 | 442 | 1,277 | 1.00 (ref) | 435 | 1,198 | 1.00 (ref) |
| 1.38–< 2.48 | 432 | 1,300 | 0.96 (0.81, 1.15) | 436 | 1,251 | 0.91 (0.77, 1.08) |
| 2.48–< 3.98 | 435 | 1,290 | 0.90 (0.75, 1.09) | 433 | 1,247 | 0.90 (0.75, 1.08) |
| 3.98–<6.23 | 326 | 787 | 0.91 (0.73, 1.13) | 279 | 762 | 0.99 (0.80, 1.23) |
| 6.23+ | 197 | 522 | 0.77 (0.60, 0.99) | 189 | 510 | 0.92 (0.72, 1.17) |
| p-value trend | 0.04 | 0.76 | ||||
OR estimated for each exposure time window separately using conditional logistic regression models stratified by country, region, sex, and 5-year age group at the reference date and adjusted for level of educational attainment. Cut points based on the 25th, 50th, 75th, and, 90th percentile of the control population’s exposure distribution for each time window. Different cut-points used for each time window due to differences in exposure distribution. Different numbers of cases/controls in different time windows due to the exclusion of participants from particular time windows where they reported not being employed. Tests for linear trend used Wald x2 tests, with categorical medians modeled as ordinal variables.