Modification Effect of Job Demand and Contingent Work Schedule on Overweight and Obesity Among Civil Servants in Taiwan

Figures & data

Table 1 Demographic Information for Two Groups with Either Fixed or Contingent Work Schedules

	Fixed Work (N=19844)	Contingent Work Schedule (N=554)	P
Gender (Men)	8496(42.7%)	366(65.8%)	<0.001
Age (years)			<0.001
<35	6204(31.3%)	173(31.2%)
35–50	8863(44.7%)	310(56.0%)
51–65	4777(24.1%)	71(12.8%)
Education level			<0.001
Senior high school	2848(4.3%)	54(9.8%)
College	2767(13.9%)	139 (25.2%)
Undergraduate	10,228(51.5%)	241(43.1%)
Graduate	6034(30.4%)	117(21.2%)
Marital status			0.001
Unmarried	6674(33.5%)	153(27.5%)
Married	13,020(65.4%)	390(70.1%)
Other	226(1.1%)	13(2.3%)
Cigarette smoking	2496(12.6%)	136(24.5%)	<0.001
Alcohol consumption	2266(11.4%)	138(24.9%)	<0.001
Betel nut chewing	648(3.3%)	62(8.7%)	<0.001
Sleep time <6 hrs	7640(38.3%)	298(53.6%)	<0.001
Physical activity <3 days	15,525(78.0%)	459(83.0%)	0.005

Note: P value was tested by Chi-square test.

Table 2 Work Characteristics in Those with Fixed or Contingent Work Schedules

	Fixed Work (N=19844)	Contingent Work (N=554)	P
Work Duration (years)
<3	3092(15.5%)	109(19.6%)	0.001
3–10	5679(28.5%)	127(22.9%)
10–20	9120(45.8%)	277(49.9%)
>20	2022(10.2%)	42(7.6%)
Supervisorial position			0.721
Yes	4206(21.1%)	121(21.8%)
No	15,694(78.9%)	435(78.2%)
Governmental employment			0.549
Central	8393(42.1%)	241(43.3%)
Local	11,556(57.9%)	315(56.7%)
High job demand	4054(20.4%)	225 (40.6%)	<0.001
Overweight	7546(38.1%)	289 (52.3%)	<0001
Obesity	2744(13.9%)	115 (20.8%)	<0001

Note: P value was tested by Chi-square test.

Table 3 Overweight, Obesity, and BMI Correlated with Two Groups Either Fixed or Contingent Work Schedules

	Fixed Work (N=19844)	Contingent Work (N=554)	OR (95% CI)
Obesity
No	17,049(86.1%)	438(85.9%)	1
Yes	2744(13.9%)	115(14.1%)	1.63**(1.32–2.01)
Overweight
No	12,247(61.9%)	264(61.5%)	1
Yes	7546(38.1%)	289(38.5%)	1.78**(1.50–2.10)
BMI (Kg/m^2)
≦18.4	1099(5.6%)	11(2.0%)	0.44**(0.24–0.81)
18.5–24	11,148(56.3%)	253(45.8%)	1
24–27	4802(24.3%)	174(31.5%)	1.60**(1.31–1.94)
27–30	1815(9.2%)	78(14.1%)	1.89**(1.46–2.45)
30–35	717(3.6%)	23(4.2%)	1.41(10.92–2.18)
>35	212(1.1%)	14(2.5%)	2.91**(2.96–5.07)

Note: **p<0.001.

Table 4 The Interaction Effect of a Contingent Work Schedule and Job Demand on Body Weight and BMI Adjusted for Age, Gender, Marital Status, Education, Tobacco Smoking, and Alcohol Consumption Using Multiple Linear Regression

Work Schedule	Job Demand	Body Weight (kg)	p	BMI (kg/m^2)	p
Fixed	Low	64.90±0.29		23.49±0.09
Fixed	High	65.30±0.33	0.400	23.63±0.11	0.226
Contingent	Low	66.69±0.66	0.004	23.83±0.21	0.019
Contingent	High	67.50±0.79	0.001	24.21±0.25	0.003

Note: Group with fixed work schedule and low job demand acts as a reference.

Table 5 Interaction Effects of Contingent Work Schedule and Job Demand on Overweight and Obesity Adjusted for Gender, Age, Marital Status, Education, Tobacco Smoking, and Alcohol Consumption Using Multiple Logistic Analysis

Work Schedule	Job Demand	Overweight	Obesity
		OR (95% CI)	OR (95% CI)
Fixed	Low	1	1
Fixed	High	1.10*(1.02–1.18)	1.12*(1.01–1.24)
Contingent	Low	1.23(0.98–1.55)	1.15(0.86–1.53)
Contingent	High	1.79**(1.35–2.38)	1.67**(1.21–2.31)
Rothman’s synergy index		2.43	2.56

Note: *p<0.01 **p<0.001.

Table 6 BMI (kg/m²) Correlated with Contingent Work Schedule and Job Demand Using Hierarchical Regression Model

	Step 1	Step 2	Step 3	Step 4
Gender (Male=Ref.)	−0.310**	−0.295**	−0.298**	−0.296**
Age (years)	−0.091**	−0.088**	−0.087**	−0.090**
Education level (Low=Ref.)	0.003	0.007	0.005	0.006**
Marital status (Unmarried=Ref.)	0.035**	0.033**	0.032**	0.031**
Smoking (No=Ref.)		0.043**	0.043**	0.043**
Alcohol consumption (No=Ref.)		−0.003	−0.003	−0.004
Supervisorial position (No=Ref.)			−0.014	−0.013
Governmental employment (Central=Ref.)			0.027**	0.027**
Contingent work schedule (Fixed=Ref.)				0.021**
Job demand (Low=Ref.)				0.017**
R^2	0.116	0.117	0.118	0.119
ΔR^2		0.001	0.001	0.001
F	655.8	443.6	335.6	270.5

Note: **p<0.001.