ORs and 95% CIs of occupational exposure to electric shocks and three lymphomas
| Agent | Non-Hodgkin's lymphoma | Chronic lymphocytic leukaemia | Multiple myeloma | |||
| Unadjusted OR (95% CI) | Adjusted OR (95% CI)* | Unadjusted OR (95% CI) | Adjusted OR (95% CI)* | Unadjusted OR (95% CI) | Adjusted OR (95% CI)* | |
| Highest level of exposure† | ||||||
| Background levels | 1.00 | 1.00 | 1.00 | |||
| Low levels | 0.94 (0.92 to 0.97) | 0.96 (0.94 to 0.98) | 0.94 (0.90 to 0.98) | 0.95 (0.91 to 0.99) | 0.99 (0.95 to 1.02) | 1.01 (0.98 to 1.05) |
| High levels | 0.93 (0.90 to 0.95) | 0.94 (0.91 to 0.97) | 0.93 (0.88 to 0.98) | 0.93 (0.87 to 0.99) | 0.96 (0.92 to 1.00) | 0.97 (0.93 to 1.02) |
| Duration of exposure above background (per 10 years)‡ | 0.99 (0.98 to 0.99) | 0.99 (0.98 to 0.99) | 0.98 (0.97 to 0.99) | 0.99 (0.98 to 1.00) | 0.99 (0.98 to 1.00) | 1.00 (0.99 to 1.01) |
| Duration of exposure to high levels (per 10 years)‡ | 0.97 (0.96 to 0.99) | 1.00 (0.99 to 1.01) | 0.98 (0.97 to 1.00) | 0.99 (0.97 to 1.01) | 0.99 (0.98 to 1.00) | 0.99 (0.98 to 1.01) |
| Cumulative exposure (tertiles of exposure) | ||||||
| 0 unit-years | 1.00 | 1.00 | 1.00 | |||
| 1–20 unit-years§ | 0.96 (0.93 to 0.99) | 0.97 (0.94 to 1.00) | 0.92 (0.87 to 0.98) | 0.93 (0.87 to 0.98) | 1.02 (0.97 to 1.06) | 1.03 (0.98 to 1.08) |
| 21–35 unit-years | 0.93 (0.90 to 0.95) | 0.94 (0.92 to 0.97) | 0.93 (0.89 to 0.97) | 0.95 (0.90 to 1.00) | 0.98 (0.95 to 1.02) | 1.00 (0.96 to 1.04) |
| 36–164 unit-years | 0.93 (0.90 to 0.96) | 0.95 (0.91 to 0.98) | 0.95 (0.90 to 1.00) | 0.97 (0.91 to 1.04) | 0.95 (0.91 to 0.99) | 0.97 (0.91 to 1.02) |
*Adjusted for social class and aromatic solvents, chlorinated solvents and other solvents on a continuous scale.
†Taking the highest exposure levels for each participant.
‡The risk associated with 10-year increase in duration of exposure; duration of exposure above background level was calculated by summing up the time that a person was exposed to both low or high levels.
§Multiplying job duration with weights based on the distribution of the intensity of extremely low frequency magnetic field exposure over the occupations to exposure rating (ie, background 0, low 1, high 4).