Table 1.

Baseline characteristics and biochemical indices among bus drivers. [PSY=psychiatric disorders]

Variables	All drivers (N=965)		Non-PSY drivers (N=811)		PSY drivers (N=85)		P-value
	N	%	N	%	N	%
Age (years)
<35	195	20.21	165	20.35	16	18.82	0.915
35–44	446	46.22	370	45.62	38	44.71
45–49	202	20.93	174	21.45	21	24.71
≥50	122	12.64	102	12.58	10	11.76
Body mass index (kg/m2)
<25	397	41.14	336	41.43	34	40.00	0.138
25–29.9	420	43.52	358	44.14	32	37.65
≥30	148	15.34	117	14.43	19	22.35
Marital status
Unmarried	174	18.03	150	18.50	11	12.94	0.432
Married	683	70.78	570	70.28	63	74.12
Others	108	11.19	91	11.22	11	12.94
Education
≤ Junior high school	263	27.25	217	26.76	26	30.59	0.541
Senior high and vocational school	629	65.18	534	65.84	51	60.00
University and College	73	7.56	60	7.40	8	9.41
Cigarette smoking
Never smokers	330	34.20	273	33.66	33	38.82	0.705
Ex-smokers	67	6.94	57	7.03	6	7.06
Current smokers	562	58.24	476	58.69	46	54.12
Alcohol use
No	739	76.58	620	76.45	63	74.12	0.547
Current	219	22.69	185	22.81	22	25.88
Moderate exercise
No	687	71.19	591	72.87	54	63.53	0.063
Yes	266	27.56	210	25.89	30	35.29
Age at first employment (years)
≤32	242	25.08	207	25.52	17	20.00	0.531
33–38	325	33.68	271	33.42	30	35.29
≥39	398	41.24	333	41.06	38	44.71
Time since first employment (years)
≤2	216	22.38	181	22.32	17	20.00	0.258
2.1–5	289	29.95	249	30.70	21	24.71
5.1–8	188	19.48	150	18.50	23	27.06
>8	272	28.19	231	28.48	24	28.24
Shift work mode
Day shift only	114	11.81	97	11.96	8	9.41	0.457
Irregular shift	793	82.18	664	81.87	73	85.88
History of chronic disease
No	700	72.54	585	72.13	64	75.29	0.535
Yes	265	27.46	226	27.87	21	24.71