Shift work by hormone receptor status
| Years shift work history* | Controls (n=1179) | ER/PR+ (n=840) | ER/PR− (n=166) | Interaction by ER/PR status‡ | ||||
|---|---|---|---|---|---|---|---|---|
| n (%) | n (%) | OR† | 95% CI | n (%) | OR† | 95% CI | ||
| None | 773 (65.6) | 547 (65.1) | – | – | 116 (69.9) | – | – | – |
| 0–14 | 312 (26.5) | 216 (25.7) | 1.00 | 0.81 to 1.23 | 37 (22.3) | 0.78 | 0.52 to 1.17 | p=0.22 |
| 15–29 | 81 (6.9) | 55 (6.6) | 0.97 | 0.68 to 1.39 | 11 (6.6) | 0.90 | 0.47 to 1.75 | p=0.84 |
| ≥30 | 13 (1.1) | 22 (2.6) | 2.37 | 1.18 to 4.76 | 2 (1.2) | 1.06 | 0.24 to 4.75 | p=0.27 |
*Using 50% of time definition.
†Model adjusted for age and centre.
‡p Values calculated from case-only model comparing ER/PR+ and ER/PR− groups.
ER, oestrogen; PR, progesterone.