Table 1.

Baseline characteristics of participants according to their exposure to shift work and number of weekly working hours.

	Shift work			Working hours (hours/week)
	Day work n=2828	Shift work (−night work) n=396	Shift work (+night work) n=115*	37 n=1689	≤27 n=436	28–36 n=455	38–44 n=381	≥45 n=453
Gender (female)	50.2%	49.5%	56.5%	41.4%	93.6%	85.1%	29.7%	22.7%
Age at exposure assessment (mean, SD)	45.6 (7.1)	45.1 (6.9)	45.4 (7.6)	45.5 (7.2)	47.3 (7.0)	45.4 (6.9)	45.1 (7.0)	44.3 (6.7)
Duration of vocational education
No education	17.6%	22.5%	24.4%	17.9%	25.9%	22.4%	13.9%	13.5%
Basic	13.2%	18.9%	25.2%	13.9%	18.6%	21.8%	8.7%	9.9%
Skilled/short	38.5%	32.8%	33.9%	42.2%	30.1%	27.9%	34.9%	39.3%
3–4 years or >4 years†	30.7%	25.8%	16.5%	26.0%	25.5%	27.9%	42.5%	37.5%
Ruminated about work‡	5.8%	8.6%	7.9%	5.2%	6.9%	6.6%	6.6%	9.1%
Had influence at work‡	87.9%	75.8%	69.6%	83.4%	84.0%	85.5%	90.3%	94.0%
Had possibilities for development‡	71.7%	64.4%	67.8%	70.0%	60.3%	68.5%	77.2%	79.8%
Smoking
Never	31.3%	28.5%	20.9%	28.8%	38.3%	32.1%	27.0%	29.6%
Previously	22.3%	17.2%	19.1%	20.1%	19.3%	22.6%	26.3%	24.3%
Yes	46.4%	54.3%	60.0%	51.2%	42.4%	45.3%	46.7%	46.1%
BMI (mean, SD)	23.9 (3.4)	24.6 (4.0)	24.2 (3.6)	24.2 (3.5)	22.9 (3.5)	23.1 (3.6)	24.6 (3.6)	24.7 (3.3)
Hypertension (yes)	7.8%	8.4%	4.4%	6.7%	9.9%	7.9%	7.6%	9.1%
Work schedule
Day work				86.9%	81.4%	76.3%	87.1%	87.9%
Shift work (−night work)				10.5%	16.0%	14.2%	10.2%	10.2%
Shift work (+night work)				2.6%	2.6%	9.5%	2.7%	1.9%
Weekly working hours
37	51.3%	45.2%	38.3%
≤27	12.1%	17.4%	9.6%
28–36	12.0%	16.4%	36.5%
38–44	11.5%	9.9%	8.7%
≥45	13.1%	11.2%	7.0%

*Three-shift workers: n=54; permanent night workers: n=61.

†3–4 years and >4 years are grouped together in the descriptive analyses in order to adhere to the rules regarding data confidentiality.

‡Usually/always.

BMI, body mass index.