Table 4.
Association of night work indicators and prostate cancer risk, by prostate cancer aggressiveness
| Permanent night work | Rotating night work | |||||||
| Gleason Score ≤7 (3+4) n=566 |
Gleason Score ≥7 (4+3) n=165 |
Gleason Score ≤7 (3+4) n=478 |
Gleason Score ≥7 (4+3) n=127 |
|||||
| Cases (n=566)/controls (n=769) | OR*† | Cases (n=165)/controls (n=769) | OR*† | Cases (n=478)/controls (n=667) | OR*† | Cases (n=127)/controls (n=667) | OR*† | |
| Never night work | 416/566 | 1.0 (Reference) | 107/556 | 1.0 (Reference) | 416/556 | 1.0 (Reference) | 107/556 | 1.0 (Reference) |
| Ever night work | 150/213 | 0.97 (0.75 to 1.25) | 58/213 | 1.41 (0.98 to 2.04) | 62/111 | 0.78 (0.55 to 1.11) | 20/111 | 0.92 (0.54 to 1.58) |
| Total duration of night work (in years) | ||||||||
| <20 | 79/107 | 1.05 (0.76 to 1.47) | 23/107 | 1.09 (0.66 to 1.81) | 36/76 | 0.69 (0.45 to 1.07) | 12/76 | 0.78 (0.40 to 1.51) |
| ≥20 | 71/106 | 0.89 (0.63 to 1.25) | 35/106 | 1.76 (1.13 to 2.75) | 26/35 | 0.96 (0.55 to 1.67) | 8/35 | 1.26 (0.55 to 2.89) |
| p-trend | 0.97 | 0.003 | 0.37 | 0.11 | ||||
| Total frequency of night work (number of cumulative nights) | ||||||||
| <1314 | 63/88 | 1.04 (0.72 to 1.49) | 27/88 | 1.27 (0.78 to 2.05) | 40/82 | 0.70 (0.46 to 1.06) | 12/82 | 0.75 (0.39 to 1.44) |
| ≥1314 | 85/125 | 1.01 (0.74 to 1.40) | 33/125 | 1.14 (0.73 to 1.77) | 22/29 | 1.00 (0.55 to 1.82) | 8/29 | 1.41 (0.61 to 3.24) |
| p-trend | 0.97 | 0.79 | 0.96 | 0.56 | ||||
| Number of consecutive nights | ||||||||
| <6 | 67/98 | 0.95 (0.67 to 1.35) | 27/98 | 1.46 (0.90 to 1.37) | 39/83 | 0.67 (0.44 to 1.01) | 19/83 | 1.23 (0.70 to 2.16) |
| ≥6 | 66/76 | 1.20 (0.83 to 1.73) | 26/76 | 1.87 (1.13 to 3.11) | 23/27 | 1.18 (0.65 to 2.14) | 1/27 | 0.16 (0.02 to 1.23) |
| p-trend | 0.28 | 0.35 | 0.75 | 0.85 | ||||
| Shift length (hours) | ||||||||
| ≤10 | 23/67 | 0.48 (0.29 to 0.80) | 11/67 | 0.88 (0.44 to 1.74) | 54/101 | 0.75 (0.52 to 1.09) | 16/101 | 0.83 (0.46 to 1.48) |
| >10 | 25/22 | 1.65 (0.90 to 3.01) | 12/22 | 2.63 (1.23 to 5.63) | 8/10 | 1.07 (0.40 to 2.82) | 4/10 | 1.76 (0.52 to 5.97) |
| p-trend | 0.75 | 0.04 | 0.21 | 0.95 | ||||
| Duration (years) × number of consecutive nights | ||||||||
| <20 × <6 | 43/56 | 1.08 (0.70 to 1.66) | 14/56 | 1.30 (0.68 to 2.47) | 23/57 | 0.60 (0.36 to 1.01) | 11/57 | 1.00 (0.50 to 2.00) |
| <20 × ≥6 | 27/33 | 1.23 (0.72 to 2.10) | 8/33 | 1.30 (0.57 to 2.93) | 13/19 | 0.96 (0.45 to 2.03) | 1/19 | 0.22 (0.03 to 1.71) |
| ≥20 × <6 | 24/42 | 0.76 (0.45 to 1.30) | 13/42 | 1.61 (0.82 to 3.16) | 16/26 | 0.78 (0.40 to 1.54) | 8/26 | 1.77 (0.75 to 4.17) |
| ≥20 × ≥6 | 39/43 | 1.16 (0.72 to 1.87) | 18/43 | 2.43 (1.32 to 4.47) | 10/8 | 1.69 (0.64 to 4.46) | 0/8 | – |
| Duration (years) × shift length (hours) | ||||||||
| <20 × ≤10 | 9/27 | 0.53 (0.24 to 1.17) | 5/27 | 1.04 (0.39 to 2.81) | 30/71 | 0.62 (0.39 to 0.99) | 9/71 | 0.64 (0.31 to 1.35) |
| <20 × >10 | 13/12 | 1.57 (0.70 to 3.52) | 3/12 | 1.11 (0.30 to 4.10) | 6/5 | 1.59 (0.46 to 5.41) | 3/5 | 2.49 (0.55 to 11.26) |
| ≥20 × ≤10 | 14/40 | 0.45 (0.23 to 0.86) | 6/40 | 0.77 (0.31 to 1.90) | 24/30 | 1.01 (0.56 to 1.81) | 7/30 | 1.31 (0.54 to 3.16) |
| ≥20 × >10 | 12/10 | 1.76 (0.73 to 4.23) | 9/10 | 4.64 (1.78 to 12.13) | 2/5 | 0.54 (0.10 to 2.99) | 1/5 | 0.99 (0.11 to 8.81) |
| Shift length (hours) × total frequency of night work (cumulative number of nights) | ||||||||
| ≤10 × < 1314 | 6/17 | 0.50 (0.19 to 1.32) | 6/17 | 2.01 (0.76 to 5.30) | 34/77 | 0.63 (0.41 to 0.99) | 11/77 | 0.74 (0.38 to 1.47) |
| ≤10 × ≥ 1314 | 17/50 | 0.48 (0.26 to 0.84) | 5/50 | 0.52 (0.20 to 1.35) | 20/24 | 1.09 (0.58 to 2.07) | 5/24 | 1.09 (0.40 to 2.99) |
| >10 × < 1314 | 7/8 | 1.21 (0.42 to 3.45) | 2/8 | 0.95 (0.19 to 4.81) | 6/5 | 1.57 (0.46 to 5.37) | 1/5 | 0.77 (0.08 to 7.12) |
| >10 × ≥ 1314 | 18/14 | 1.97 (0.94 to 4.09) | 10/14 | 3.79 (1.58 to 9.12) | 2/5 | 0.55 (0.10 to 3.02) | 3/5 | 2.86 (0.65 to 12.50) |
| Shift length (hours) × number of consecutive nights | ||||||||
| ≤10 × <6 | 8/26 | 0.45 (0.20 to 1.04) | 5/26 | 1.03 (0.38 to 2.80) | 35/76 | 0.66 (0.42 to 1.02) | 15/76 | 1.08 (0.59 to 1.99) |
| ≤10 × ≥6 | 13/33 | 0.53 (0.27 to 1.04) | 5/33 | 0.82 (0.31 to 2.18) | 19/24 | 1.10 (0.57 to 2.09) | 1/24 | 0.19 (0.02 to 1.42) |
| >10 × <6 | 3/7 | 0.71 (0.18 to 2.83) | 1/7 | 0.51 (0.06 to 4.43) | 4/7 | 0.76 (0.21 to 2.78) | 4/7 | 2.50 (0.69 to 9.03) |
| >10 × ≥6 | 19/13 | 2.12 (1.02 to 4.44) | 10/13 | 4.30 (1.77 to 10.44) | 4/3 | 1.74 (0.37 to 8.06) | 0/3 | – |
| Direction of shift rotation | ||||||||
| Forward | 42/71 | 0.82 (0.54 to 1.25) | 12/71 | 0.86 (0.45 to 1.69) | ||||
| Backward | 5/13 | 0.73 (0.28 to 1.91) | 3/13 | 1.10 (0.30 to 4.04) | ||||
| Forward and backward | 13/27 | 0.70 (0.34 to 1.40) | 5/27 | 0.97 (0.36 to 2.62) | ||||
| Speed of shift rotation (in days) | ||||||||
| Short (≤3) | 9/19 | 0.70 (0.29 to 1.65) | 4/16 | 1.16 (0.37 to 3.62 | ||||
| Intermediate (4–5) | 27/57 | 0.71 (0.43 to 1.15) | 13/57 | 1.26 (0.65 to 2.43) | ||||
| Long (≥6) | 18/20 | 1.18 (0.60 to 2.34) | 1/20 | 0.20 (0.03 to 1.52) | ||||
| Short/intermediate/ long |
8/18 | 0.62 (0.26 to 1.47) | 2/18 | 0.64 (0.14 to 2.85) | ||||
*Adjusted for age, family history of prostate cancer, race, education level.
† 95% CI.