Table 3.
Association between night shift work and cancer-specific (≥ 200 deaths) mortality in NHS, 1988-2010 (n=74,862).
| Night shift work duration |
|||||
|---|---|---|---|---|---|
| Mortality | Never | 1–5 years | 6–14 years | ≥15 years | p for trend |
| Lung cancer | |||||
| No. of deaths | 501 | 523 | 168 | 150 | |
| Age-adjusted HR (95% CI) | 1.00 (ref) | 1.02 (0.91, 1.16) | 1.14 (0.96, 1.36) | 1.44 (1.20, 1.73) | <0.001 |
| Multivariable HR (95% CI)a | 1.00 (ref) | 1.05 (0.92, 1.19) | 0.99 (0.83, 1.18) | 1.25 (1.04, 1.51) | 0.05 |
| Breast cancer | |||||
| No. of deaths | 269 | 293 | 79 | 55 | |
| Age-adjusted HR (95% CI) | 1.00 (ref) | 1.05 (0.89, 1.25) | 1.04 (0.81, 1.34) | 1.08 (0.80, 1.44) | 0.64 |
| Multivariable HR (95% CI)a | 1.00 (ref) | 1.07 (0.90, 1.26) | 0.99 (0.76, 1.27) | 0.99 (0.74, 1.33) | 0.83 |
| Ovarian cancer | |||||
| No. of deaths | 180 | 168 | 47 | 30 | |
| Age-adjusted HR (95% CI) | 1.00 (ref) | 0.92 (0.74, 1.13) | 0.90 (0.65, 1.24) | 0.86 (0.58, 1.27) | 0.41 |
| Multivariable HR (95% CI)a | 1.00 (ref) | 0.95 (0.77, 1.18) | 0.89 (0.64, 1.23) | 0.82 (0.55, 1.22) | 0.27 |
| Pancreatic cancer | |||||
| No. of deaths | 149 | 173 | 52 | 33 | |
| Age-adjusted HR (95% CI) | 1.00 (ref) | 1.12 (0.90, 1.39 | 1.20 (0.88, 1.65) | 1.10 (0.75, 1.60) | 0.47 |
| Multivariable HR (95% CI)a | 1.00 (ref) | 1.12 (0.90, 1.40) | 1.14 (0.83, 1.58) | 1.03 (0.70, 1.51) | 0.77 |
| Colorectal cancer | |||||
| No. of deaths | 180 | 176 | 56 | 52 | |
| Age-adjusted HR (95% CI) | 1.00 (ref) | 0.95 (0.77, 1.17) | 1.07 (0.80, 1.45) | 1.42 (1.04, 1.94) | 0.02 |
| Multivariable HR (95% CI)a | 1.00 (ref) | 0.98 (0.79, 1.21) | 1.05 (0.77, 1.42) | 1.33 (0.97, 1.83) | 0.07 |
| Non Hodgkin’s Lymphoma | |||||
| No. of deaths | 103 | 89 | 34 | 26 | |
| Age-adjusted HR (95% CI) | 1.00 (ref) | 0.85 (0.66, 1.09) | 0.94 (0.65, 1.37) | 1.11 (0.74, 1.66) | 0.57 |
| Multivariable HR (95% CI)a | 1.00 (ref) | 0.87 (0.67, 1.12) | 0.96 (0.66, 1.40) | 1.06 (0.71, 1.58) | 0.77 |
| Other cancer (ICD=199) | |||||
| No. of deaths | 146 | 145 | 35 | 32 | |
| Age-adjusted HR (95% CI) | 1.00 (ref) | 0.95 (0.76, 1.20) | 0.80 (0.55, 1.16) | 1.05 (0.72, 1.55) | 0.87 |
| Multivariable HR (95% CI)a | 1.00 (ref) | 0.98 (0.77, 1.23) | 0.75 (0.52, 1.09) | 0.94 (0.63, 1.38) | 0.39 |
Boldface indicates statistical significance (p<0.05).
HR, hazard ratio; NHS, Nurses’ Health Study.
Multivariable model adjusted for age (continuous), alcohol consumption (none, 0.1-4.9, 5.0-14.9, ≥15.0 g/d), physical exercise (metabolic equivalent values; quintiles), multivitamin use (yes, no), menopausal status (premenopausal, postmenopausal) and postmenopausal hormone use (never, past and current), physical exam in the past 2 years (no, yes for symptoms and yes for screenings), healthy eating score (quintiles), smoking status (never, former, current), pack-years (<10, 10-19, 20-39, ≥40 for former smokers; <25, 25-44, 45-64, ≥65 for current smokers), BMI (kg/m2; <21, 21-22.9, 23-24.9, 25-27.4, 27.5-29.9, 30-34.9, ≥35) and husband’s education (less than high school, some high school, high school graduate, college, graduate school, missing category).