Table 4.
Risk of invasive and borderline ovarian cancer, by tumor subtype, in association with working the nightshift
| High Grade Serous | Low Grade and Borderline Serousb | Invasive and Borderline Mucinousc | Endometrioid | Clear Cell | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| |||||||||||||||||
| Controls (%)(n=1832) | Cases (%)(n=834) | ORa (95% CI) | Cases (%)(n=240) | ORa (95% CI) | Cases (%)(n=181) | ORa (95% CI) | Cases (%)(n=129) | ORa (95% CI) | Cases (%)(n=83) | ORa (95% CI) | |||||||
| Worked nightshift | |||||||||||||||||
| Never | 1420 | (77.5) | 606 | (72.7) | 161 | (67.1) | 121 | (66.8) | 100 | (77.5) | 64 | (77.1) | |||||
| Ever | 412 | (22.5) | 228 | (27.3) | 1.29 (1.06–1.57) | 79 | (32.9) | 1.51 (1.12–2.05) | 60 | (33.1) | 1.55 (1.10–2.17) | 29 | (22.5) | 0.91 (0.57–1.43) | 19 | (22.9) | 0.91 (0.52–1.59) |
| Cumulative nightshift work-years | |||||||||||||||||
| Never | 1420 | (77.5) | 606 | (72.7) | 161 | (67.1) | 121 | (66.9) | 100 | (77.5) | 64 | (77.1) | |||||
| 4mos-1 yr | 97 | (5.3) | 39 | (4.7) | 0.97 (0.65–1.44) | 16 | (6.7) | 1.34 (0.76–2.38) | 11 | (6.1) | 1.29 (0.66–2.51) | 8 | (9.2) | 1.31 (0.59–2.90) | 6 | (7.2) | 1.38 (0.55–3.43) |
| >1–3 yrs | 121 | (6.6) | 50 | (6.0) | 1.01 (0.71–1.44) | 23 | (9.6) | 1.41 (0.86–2.31) | 18 | (9.9) | 1.46 (0.85–2.53) | 12 | (5.8) | 1.34 (0.68–2.65) | 7 | (6.0) | 1.06 (0.44–2.54) |
| >3–7 yrs | 85 | (4.6) | 83 | (10.0) | 2.30 (1.65–3.21) | 25 | (10.4) | 2.24 (1.36–3.71) | 20 | (11.1) | 2.46 (1.43–4.2) | 5 | (3.9) | 0.61 (0.23–1.66) | 3 | (3.6) | 0.60 (0.17–2.11) |
| >7 yrs | 108 | (5.9) | 55 | (6.6) | 1.09 (0.77–1.55) | 15 | (6.3) | 1.18 (0.66–2.13) | 11 | (6.1) | 1.12 (0.58–2.18) | 4 | (3.1) | 0.43 (0.15–1.24) | 3 | (3.6) | 0.59 (0.17–1.98) |
| unknown | 1 | (<1) | 1 | (<1) | - | 0 | (0) | - | 0 | (0) | - | 0 | (0) | - | 0 | (0) | - |
*
23 cases with unspecified borderline tumors excluded
a
Adjusted for age at reference, county, reference year, duration of oral contraceptive use, number of full term pregnancies, and BMI at age 30
b
Low Grade Serous n = 23, Borderline Serous n = 217
c
Invasive Mucinous n = 32, Borderline Mucinous n = 149