Table 3

HRs for shift work exposure groups applying conditional Cox analysis of twin pairs discordant for prostate cancer (no cancer as reference) for prediction of prostate cancer after baseline among male night workers, and with 95% CI. n=332

Duration of exposure, yearsN (%)Complete follow-up
HR (95% CI)*
Follow-up to 60 years
HR (95% CI)
No night work (ref)
Working nights for:
0 years
1–5 years
6–10 years
11–20 years
21–45 years
225 (68)
42 (13)
19 (6)
22 (7)
24 (7)
1
1.02 (0.48 to 2.18)
1.97 (0.64 to 6.02)
0.88 (0.32 to 2.43)
1.05 (0.39 to 2.84)
1
0.88 (0.26 to 2.46)
1.24 (0.26 to 5.82)
0.87 (0.26 to 2.93)
0.57 (0.13 to 2.45)
  • *Follow-up until December 31 2010.

  • †Follow-up until the age of 60.