Age category, smoking status, numbers of cigarettes smoked per day and number of years smoked, alcohol use, educational level, body mass index and occupational exposure to extremely low-frequency magnetic fields for the subcohort and all cardiovascular deaths (cases) by sex
| Subcohort | Cases Total cardiovascular mortality | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Male | Female | Male | Female | |||||||||
| n | %/mean | SD | n | %/mean | SD | n | %/mean | SD | n | %/mean | SD | |
| Ever exposed to ELF-MF | ||||||||||||
| Background (%) | 926 | 48.8 | 977 | 50.3 | 2106 | 46.8 | 825 | 49.9 | ||||
| Low (%) | 855 | 44.1 | 954 | 49.1 | 1934 | 43.0 | 810 | 48.9 | ||||
| High (%) | 156 | 8.1 | 13 | 0.6 | 456 | 10.1 | 20 | 1.2 | ||||
| Duration of ever low or high exposed (years; mean,SD) | 1011 | 26.7 | 14.2 | 967 | 11.2 | 9.5 | 2390 | 26.6 | 14.0 | 830 | 10.7 | 9.7 |
| Cumulative exposure* Categorical | ||||||||||||
| Background (%) 0 unit-years | 926 | 47.8 | 977 | 50.3 | 2106 | 46.8 | 825 | 49.8 | ||||
| 1st tertile of exposed (%) 0.5–9 unit-years | 160 | 8.3 | 544 | 28.0 | 348 | 7.7 | 491 | 29.7 | ||||
| 2nd tertile of exposed (%) 9.5–28 unit-years | 272 | 14.0 | 353 | 18.1 | 682 | 15.2 | 277 | 16.7 | ||||
| 3rd tertileof exposed (%) 28.5–208 unit-years | 579 | 29.9 | 70 | 3.6 | 1360 | 30.3 | 62 | 3.8 | ||||
| Continuous (unit×years; mean, SD) | 1937 | 18.6 | 29.1 | 1944 | 5.7 | 9.4 | 4496 | 20.2 | 32.1 | 1655 | 5.6 | 9.2 |
*Cumulative exposure was calculated by multiplying per job the duration with exposure level using arbitrary weights (0 for background, 1 for low and 4 for high exposure). The resulting unit×years per job were then summed across all jobs in the job history.
ELF-MF, extremely low-frequency magnetic fields.