Characteristics of the study population
| Shift workers (n=121) n (%) | Day workers (n=150) n (%) | |
|---|---|---|
| Age* (mean±SD) | 38.4 (11.6) | 45.0 (9.5) |
| Marital status† | ||
| Married or common law | 77 (63.6) | 112 (75.2) |
| Widowed, separated or divorced | 12 (9.9) | 18 (12.1) |
| Single or never married | 32 (26.5) | 19 (12.8) |
| Number of children† | ||
| None | 58 (47.9) | 33 (22.0) |
| 1–2 | 49 (40.5) | 85 (56.7) |
| ≥3 | 14 (11.6) | 32 (21.3) |
| Education† | ||
| High school | 0 | 10 (6.7) |
| Postsecondary (certificate/diploma) | 58 (47.9) | 84 (56.0) |
| University degree (Undergraduate, Masters, PhD, etc) | 63 (52.1) | 56 (37.3) |
| Household income | ||
| <$50 000 | 5 (4.1) | 18 (12.0) |
| $50 000–$99 999 | 73 (60.3) | 76 (50.7) |
| ≥$100 000 | 43 (35.5) | 56 (37.3) |
| Postmenopausal | 31 (29.0) | 49 (34.8) |
| Use of hormone replacement therapy | 5 (4.1) | 13 (8.7) |
| Diagnosed with a sleep disorder | 6 (5.0) | 13 (8.7) |
| Family history of heart attack before age 60 | 16 (13.2) | 26 (17.3) |
| Meets physical activity guidelines | 71 (58.7) | 77 (51.3) |
| Overweight (kg/m2) | ||
| BMI ≥25 to <30 | 40 (33.1) | 45 (30.0) |
| BMI ≥30 | 29 (24.0) | 35 (23.3) |
| History of/current medication for | ||
| High cholesterol | 7 (5.8) | 8 (5.3) |
| High blood pressure | 10 (8.3) | 19 (12.7) |
| Smoking status† | ||
| Current smoker | 7 (5.8) | 19 (12.7) |
| Former smoker | 23 (19.0) | 40 (26.7) |
| Never-smoker | 91 (75.2) | 91 (60.7) |
| Frequency of alcohol consumption† | ||
| ≤Once a month | 55 (45.6) | 50 (33.3) |
| 2–4 times a month | 42 (34.7) | 46 (30.7) |
| >Once a week | 24 (19.8) | 54 (36.0) |
| Employment category‡ | ||
| Laboratory and diagnostic services | 0 | 10 (6.7) |
| Nursing | 112 (92.6) | 81 (54.0) |
| Occupational therapy, physiotherapy, radiation therapy, respiratory therapy | 5 (4.1) | 10 (6.7) |
| Support services | 2 (2.0) | 10 (6.7) |
| Administrative support | 2 (1.7) | 34 (22.7) |
| Management | 0 | 5 (3.3) |
| Position† | ||
| Permanent | 121 (100) | 142 (94.7) |
| Temporary | 0 | 7 (4.7) |
| Casual | 0 | 1 (0.7) |
| History of rotating shift work including night shifts† | ||
| Never (year) | 0 | 38 (25.3) |
| >0 to ≤7 | 46 (38.0) | 43 (28.7) |
| >7 to ≤15 | 28 (23.1) | 32 (21.3) |
| >15 years | 47 (38.8) | 37 (24.7) |
| Duration of one shift/work day‡ | ||
| 8 h | 0 | 114 (76.0) |
| 12 h | 116 (95.9) | 11 (7.3) |
| Various shifts | 4 (3.3) | 10 (6.7) |
| Some other shifts | 1 (0.8) | 15 (10.0) |
Variables marked with a symbol indicate that the p value was <0.05.
*Wilcoxon rank sum test.
†χ2 test.
‡Fisher's exact test.
BMI, body mass index.