Relationship of Sleep Quality, Physical Stress, Psychological Stress, and Job Stress among Residents

So-Young Yoo; Young-Ah Choi; Young-Kyu Park; Sung-Min Cho; Kyung-Shik Lee; Ga-Young Joo; Hyun Keun Lee

doi:10.15384/kjhp.2017.17.1.9

Korean J Health Promot > Volume 17(1); 2017 > Article

Relationship of Sleep Quality, Physical Stress, Psychological Stress, and Job Stress among Residents

Original Article

Korean Journal of Health Promotion 2017;17(1):9-19.

Published online: January 19, 2017

DOI: https://doi.org/10.15384/kjhp.2017.17.1.9

Relationship of Sleep Quality, Physical Stress, Psychological Stress, and Job Stress among Residents

So-Young Yoo, Young-Ah Choi, Young-Kyu Park, Sung-Min Cho, Kyung-Shik Lee, Ga-Young Joo, Hyun Keun Lee

Department of Family Medicine, Bundang Jesaeng Hospital, Seongnam, Korea

Corresponding author : Young-Ah Choi, MD Department of Family Medicine, Bundang Jesaeng Hospital, 20 Seohyeon-ro 180beon-gil, Bundang-gu, Seongnam 13590, Korea
Tel: +82-31-779-0357, Fax: +82-31-779-0827 E-mail: grchoi1@dmc.or.kr

Received November 08, 2016 Accepted January 17, 2017

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

요약

Background:

The purpose of this study is to identify the relationship of sleep quality, physical stress, psychological stress, and job stress among residents and to examine correlations of sleep quality, physical stress, psychological stress, and job stress according to average of working hours per day, frequency of night duty, sleep onset time on night duty and sleeping hour on night duty.

Methods:

A descriptive correlation study included 164 residents working at 13 secondary and tertiary hospitals in Gyeong-gi Province who completed a self-administered structured questionnaires. The data were collected from June 1 to August 31, 2016. and analyzed through frequency, percentage, t-test, ANOVA, Scheffe's test, multiple regression analysis by SPSS program version 22.0 (IBM Corp., Chicago, IL, USA).

Results:

The average level of residents’ sleep quality, physical stress, psychological stress, and job stress were 40.30, 16.74, 15.96, and 26.79, respectively. Sleep quality, physical, psychological and job stress have shown statistically significant correlations according to average of working hours per day, frequency of night duty, sleep onset time on night duty and sleeping hour on night duty. Poor sleep quality is related to higher physical, psychological and job stress.

Conclusions:

Residents’ average of working hours per day is long and sleeping hour on night duty is scarce. Due to this, the level of residents’ sleep quality is poor and physical, psychological and job stress are severe. Obviously, sleep quality showed a positive correlation with physical, psychological and job stress. It is necessary to develop effective program to improve the residents’ sleep quality and reduce physical, psychological and job stress.

Keywords: Sleep hygiene, Stress, physiological, Stress, psychological

Figure 1.

Correlation of degree of Sleep quality, physical and psychological stress, job stress related to average of working hours, average of ND per week, sleep onset time on ND, sleeping hour on ND.

Table 1.

Baseline characteristics

Characteristics	Categories	M±SD	No.	Freq. (%)
Gender	Male		85	51.8
Gender	Female		79	48.2
Age	27-29	31.8±4.6	164 41	100.0 25.0
	30-32		54	32.9
	33-35		55	33.5
	36-38		14	8.5
BMI^a	Underweight		6	3.7
	Normal		76	46.3
	Overweight		82	50.0
Marital status	Single		83	50.6
Marital status	Married		81	49.4
Religion	Christianity		41	25.0
	Catholic		32	19.5
	Buddhism		11	6.7
	None		80	48.8
Education	Medical college		116	70.7
Education	Medical graduate school		48	29.3
Department	IM		30	18.3
	FM		41	25.0
	PD		18	11.0
	PY		2	1.2
	Rad		12	7.3
	DM		11	6.7
	EM		8	4.9
	PS		10	6.1
	OS		10	6.1
	ENT		11	6.7
	EYE		11	6.7
Resident grade	1		74	45.1
	2		33	20.1
	3		40	24.4
	4		17	10.4
Smoking	Non-smoker		134	81.7
Smoking	Smoker		30	18.3
Socioeconomic satisfaction	High		88	53.7
	Moderate		73	44.5
	Low		3	1.8
Frequency of exercise (per week)	0		45	27.4
	1		41	25.0
	2		56	34.1
	3		18	11.0
	Over 4		4	2.4
Frequency of drink (per week)	0		17	10.4
	1		41	25.0
	2		45	27.4
	3		47	28.7
	Over 4		14	8.5
Frequency of caffeine intake (per day)	1		15	9.1
	2		51	31.1
	3		47	28.7
	Over 4		51	31.1
Average of working hours (per day)		11.52±2.27	164	100.0
	<10		38	23.2
	10-12		68	41.5
	>12		58	35.4
Frequency of ND^b (day per week)	0-1		56	34.1
	2-3		57	34.8
	4-5		29	17.7
	6-		22	13.4
Sleep onset time^c on ND^b	<22		3	1.8
	22-23		55	33.5
	24-25		43	26.2
	26-27		61	37.2
	28-		2	1.2
Sleeping hour on ND^b (per day)	1-2		53	32.3
	3-4		23	14.0
	5-6		39	23.8
	7-8		49	29.9

Abbreviations: M, mean; SD, standard deviation; No., number; Freq., frequency; BMI, body mass index; IM, internal medicine; FM, family medicine; PD, pediatrics; PY, psychiatrics; Rad, radiology; DM, dermatology; EM, emergency medicine; PS, plastic surgery; OS, orthopedic surgery; ENT, otorhinolaryngology; EYE, ophthalmology; ND, night duty. Values are presented as mean±standard deviation, number or frequency (%).

^aBMI: underweight (<18), normal (18-23), overweight (>23).

^bND: emergency room duty included.

^c25 indicate ante meridiem (AM) 1, 26 indicate AM 2, 27 indicate AM 3, 28 indicate AM 4.

Table 2.

Degree of Sleep quality, physical and psychological stress, job stress

	Question no.	Total score		Question score
	Question no.	M±SD	Min.-Max.	M±SD	Min.-Max
Sleep quality	28	40.30±11.83	13.00-60.00	1.44±1.13	0-3
Physical stress	15	16.74±8.26	0.00-34.00	1.12±1.20	0-3
Psychological stress	15	15.96±10.79	0.00-37.00	1.06±1.08	0-3
Job stress	9	26.79±5.79	10.00-36.00	2.98±1.11	0-4

Abbreviations: M, mean; SD, standard deviation; No., number; Min., minimum value; Max., maximum value. Values are presented as mean±standard deviation.

Table 3.

Degree of sleep quality related to baseline characteristics

Characteristics	Categories	M±SD	t or F	P	Scheffe
Gender	Male	40.15±5.79	-0.169	0.866^d
	Female	40.47±4.92
Age	27-29	49.22±6.36	1.532	0.308^e
	30-32	39.63±3.60
	33-35	36.58±4.25
	36-38	31.43±5.85
BMI^a	Underweight	43.67±5.36	0.280	0.756^e
	Normal	40.42±4.14
	Overweight	39.95±3.12
Marital status	Single	40.34±4.68	0.035	0.972^d
	Married	40.27±5.06
Religion	Christianity	32.98±4.07	0.208	0.984^e
	Catholic	41.75±4.85
	Buddhism	53.18±3.74
	None	41.71±5.24
Education	Medical college	40.28±4.27	-0.051	0.959^d
	Medical graduate school	40.38±3.84
Department	IM	42.10±5.85	2.126	0.026^e	-
	FM PD	39.20±3.54 35.33±3.58
	PY	41.50±3.19
	Rad	33.75±4.87
	DM	35.64±5.05
	EM	37.25±4.29
	PS	47.60±5.90
	OS	45.90±4.61
	ENT	44.10±2.48
	EYE ^a	46.00±2.39			^e
Resident grade	1^a	47.08±4.59	35.063 <	<0.001	^e a, b>c, d
	2^b	41.88±5.89
	3^c	31.83±3.32
	4^d	27.71±5.10
Smoking	Non-smoker	39.23±4.93	-2.494	0.014^d
	Smoker	45.10±3.24		^e
Socioeconomic satisfaction	High Moderate	36.90±2.09 44.79±4.20	0.039	0.401^e
	Low	31.00±4.00
Frequency of exercise (per week)	0^a	48.44±4.80	12.021 <	<0.001	^e a>d
	1^b	39.63±5.10
	2^c	37.86±2.37
	3^d	30.06±3.48
	Over 4^e	36.00±3.79
Frequency of drink (per week)	0^a	38.29±4.85	6.638 <	<0.001	^e c>d, e
	1^b	39.93±4.40
	2^c	47.11±5.27
	3^d	36.47±5.29
	Over 4^e	34.86±4.29
Frequency of caffeine intake (per day)	1^a	34.93±4.69	4.264	0.006^e	d>a
	2^b	37.84±4.67
	3^c	40.02±3.09
	Over 4^d	44.61±3.93
Average of working hours (per day) Average of ND^b (day per week)	<10^a	29.87±3.06	62.699 <	<0.001	^e c>b>a
	10-12^b	37.87±4.60
	>12^c	50.00±4.14
	0-1^a	30.04±3.89	50.462 <	<0.001	^e d>b, c>a
	2-3^b	43.33±4.80
	4-5^c	43.48±4.32
		Over 6^d	54.41±5.79
Sleep onset time^c on ND^b	<22^a 22-23^b	26.33±3.09 34.18±3.17	18.999 <	<0.001	^e d>a
	24-25^c	37.21±4.93
	26-27^d	48.72±4.81
	Over 28^e	39.50±4.19
Sleeping hour on ND^b (per day)	1-2^a 3-4^b 5-6^c	48.15±5.63 47.91±4.00 34.72±4.39	32.541 <	<0.001	^e a, b>c, d
	7-8^d	32.69±3.99

^aBMI: underweight (<18), normal (18-23), overweight (>23).

^bND: emergency room duty included.

^c25 indicate ante meridiem (AM) 1, 26 indicate AM 2, 27 indicate AM 3, 28 indicate AM 4.

^dCalculated by t-test.

^eCalculated by ANOVA.

Table 4.

Degree of physical stress, psychological stress and job stress related to baseline characteristics

Characteristics	Categories	Physical stress				Psychological stress				Job stress
Characteristics	Categories	M±SD	t or F	P	Scheffe^f	M±SD	t or F	P	Scheffe^f	M±SD	t or F	P	Scheffe^f
Gender	Male	15.38±2.29	-2.225	0.027^d		16.54±1.93	0.710	0.479^d		26.88±2.89	0.219	0.827^d
Gender	Female	18.22±2.02				15.34±1.67				26.68±2.73
Age	27-29	21.93±2.51	0.712	0.141^e		23.66±2.57	0.997	0.493^e		29.59±3.70	0.717	0.965^e
	30-32	17.39±2.55				14.63±1.27				25.48±2.88
	33-35	13.85±2.12				13.87±1.92				26.24±2.15
	36-38	10.43±3.04				6.79±1.35				25.79±3.48
BMI^a	Underweight	24.83±3.93	0.327	0.056^e		21.50±2.53	1.096	0.337^e		31.33±2.88	1.949	0.146^e
	Normal	17.20±1.87				15.10±1.85				26.57±2.75
	Overweight	15.73±2.23				16.37±1.24				26.66±3.35
Marital status	Single	17.18±2.46	0.683	0.496^d		16.61±1.78	0.780	0.437^d		26.20±3.59	-1.305	0.194^d
Marital status	Married	16.30±2.04				15.30±1.75				27.38±3.96
Religion	Christianity	11.56±1.04	0.349	0.060^e		10.05±0.80	0.910	0.079^e		26.10±2.81	1.268	0.287^e
	Catholic	18.31±2.47				16.16±1.27				26.38±2.67
	Buddhism	23.73±3.76				26.27±2.88				29.81±1.27
	None	17.81±2.12				17.50±1.92				26.89±2.29
Education	Medical college	16.97±2.25	0.554	0.581^d		15.18±1.69	-1.449	0.149^d		26.62±3.17	-0.569	0.570^d
Education	Medical graduate school	16.19±1.34				17.85±1.91				27.19±3.87
Department	IM^a	19.70±2.26	1.219	0.283^e		17.30±2.85	3.961	<0.001^e	^e -	30.97±4.03	13.460	<0.001^e	^e a>b
	FM	15.24±1.04				14.71±1.48				26.80±3.80
	PD	14.56±1.34				12.67±2.27				24.72±2.17
	PY	19.00±2.24				22.50±2.54				25.50±2.95
	Rad^b	14.58±2.19				3.25±0.84				15.33±2.35
	DM	16.64±2.66				11.91±1.72				23.45±2.94
	EM	12.13±1.73				18.50±2.45				25.38±3.00
	PS	19.00±2.17				22.20±3.38				29.60±4.14
	OS	17.90±1.38				22.10±3.24				28.50±4.88
	ENT	17.64±1.81				21.55±2.76				29.27±3.82
	EYE	19.27±2.12				20.45±2.21				29.18±3.14
Resident grade	1^a	20.45±3.52	19.417	<0.001^e	^e a, b>c, d	22.76±1.54	51.927	0.011^e	a, b>c, d	28.62±3.55	8.336	<0.001^e	^e a>c, d
	2^b	18.33±3.36				17.91±2.43				27.39±3.17			b>d
	3^c	10.88±2.44				7.18±0.92				24.73±2.35
	4^d	11.35±1.10				3.29±0.80				22.53±2.84
Smoking	Non-smoker	15.72±2.85	-3.479	<0.001^d	^d	14.42±2.46	-4.057	<0.001^d	^d	26.16±3.76	-2.980	0.003^d
Smoking	Smoker	21.33±2.63				22.87±1.57				29.57±3.12
Socioeconomic satisfaction	High Moderate	14.72±1.79 19.51±1.11	0.825	0.101^e		12.64±1.36 20.18±2.03	1.353	0.851^e		20.16±2.62 24.21±2.73	32.569	0.006^e	c>a, b
Socioeconomic satisfaction	Low	9.00±1.90				11.00±1.29				30.67±3.14
Frequency of exercise (per week)	0^a 1^b 2^c	21.31±2.13 17.24±2.84 14.00±2.12	7.021	<0.001^e	- ^e	23.29±2.44 16.27±1.84 12.95±1.55	13.018	<0.001^e	a>d ^e	28.98±3.62 27.15±2.57 26.63±3.85	7.458	<0.001^e	^e a>d
	3^d	12.67±2.31				6.11±0.94				20.83±2.95
	Over 4^e	17.00±1.89				17.00±1.85				27.50±3.26
Frequency of drink (per week)	0^a 1^b 2^c	16.12±1.89 17.29±2.12 21.64±2.18	0.168	0.638^e		14.06±1.89 18.32±1.94 19.49±2.14	1.132	0.303^e		29.29±3.15 27.07±3.98 28.16±3.06	1.274	0.113^e
	3^d	13.28±1.05				11.53±1.99				24.94±2.78
	Over 4^e	11.79±1.83				14.93±1.78				24.71±2.39
Frequency of caffeine intake (per day)	1^a 2^b 3^c	10.67±1.85 14.73±2.77 16.11±2.42	0.058	0.051^e		12.80±1.59 14.10±1.86 14.74±1.37	3.540	0.016^e	-	25.27±1.85 26.25±2.72 26.55±3.42	1.242	0.296^e
Frequency of caffeine intake (per day)		Over 4^d	21.14±3.90				19.88±2.10				27.98±3.12
Average of working hours (per day)	<10^a	12.32±2.65	37.784	<0.001^e	^e c>a, b	3.79±0.66	125.789	<0.001^e	^e c>b>a	22.03±2.23	29.750	<0.001	^e c>b>a
	10-12^b	13.90±2.13				14.28±1.96				26.68±3.00
	>12^c	23.00±2.03				25.91±2.29				30.03±3.92
Average of ND^b (day per week)	0-1^a	10.96±2.34	40.376	<0.001^e	^e d>b, c>a	5.88±0.91	89.198	<0.001^e	^e d>b, c>a	23.95±4.44	10.979	<0.001	^e d>a, b
	2-3^b	18.46±3.18				17.18±2.47				27.26±3.92			c>a
	4-5^c	19.07±2.29				21.34±2.75				28.00±3.71
	Over 6^d	27.91±3.78				31.41±3.79				31.18±4.89
Sleep onset time^c on ND^b	<22^a ^b	11.67±1.03	7.166	<0.001^e	^e -	8.00±1.27	31.252	<0.001^e	^e d>a, b	19.00±2.19	14.283	<0.001	^e e>a
	22-23^b	13.29±1.77				8.69±1.28				23.76±2.19
	24-25^c	16.21±1.21				13.28±1.19				26.21±2.51
	26-27^d	20.62±2.52				21.93±2.74				27.28±3.36
	Over 28^e	22.50±3.12				22.00±2.67				30.50±3.54
Sleeping hour on ND^b (per day)	1-2^a	24.02±2.15	20.577	<0.001^e	^e a, b>c, d	24.85±1.96	63.177	<0.001^e	^e a, b>c>d	30.74±4.03	31.420	<0.001	^e a, b>c, d
	3-4^b	24.00±2.56				21.70±2.95				29.87±3.72
	5-6^c	12.97±2.39				13.28±2.01				24.72±2.15
	7-8^d	12.80±1.51				5.80±0.63				22.71±1.48

Abbreviations: M, mean; SD, standard deviation; BMI, body mass index; IM, internal medicine; FM, family medicine; PD, pediatrics; PY, psychiatrics; Rad, radiology; DM, dermatology; EM, emergency medicine; PS, plastic surgery; OS, orthopedic surgery; ENT, otorhinolaryngology; EYE, ophthalmology; ND, night duty. Values are presented as mean±standard deviation and P value.

^aBMI: underweight (<18), normal (18-23), overweight (>23).

^bND: emergency room duty included.

^c25 indicate ante meridiem (AM) 1, 26 indicate AM 2, 27 indicate AM 3, 28 indicate AM 4.

^dCalculated by t-test.

^eCalculated by ANOVA.

^fP value<0.05, Scheffe's test: significant difference among group marked a, b, c, d, and e.

Table 5.

Correlation of degree of sleep quality, physical and psychological stress, job stress

	Sleep quality			Physical stress			Psychological stress			Job stress
	β	SE	P	β	SE	P	β	SE	P	β	SE	P
Sleep quality	-	-	-	0.304	0.063	0.001	0.498	0.056	<0.001	0.177	0.053	0.004
Physical stress	0.220	0.093	0.001	-	-	-	0.286	0.075	<0.001	0.031	0.065	0.036
Psychological stress	0.591	0.079	<0.001	0.467	0.072	<0.001	-	-	-	0.449	0.061	<0.001
Job stress	0.093	0.116	0.004	0.023	0.096	0.036	0.198	0.093	<0.001	-	-	-
	F=114.416, P<0.001,			F=68.216, P<0.001,			F=145.573, P<0.001,			F=34.317, P<0.001,
	R²=0.682, adjusted			R²=0.561, adjusted			R²= 0.732, adjusted			R²=0.392, adjusted
	R²=0.676			R²=0.553			R²=0.727			R²=0.380

Abbreviations: β, standardized regression coefficient; SE, standard error. Values are presented as standardized regression coefficient, standard error and P value. Calculated by multiple linear regression analyses adjusted by gender, age, marital status, education, department, and smoking.

Table 6.

Correlation of degree of Sleep quality, physical and psychological stress, job stress related to average of working hours, average of ND per week, sleep onset time on ND, sleeping hour on ND

	Sleep quality			Physical stress			Psychological stress			Job stress
	β	SE	P	β	SE	P	β	SE	P	β	SE	P
Average of working hours	0.188	1.425	0.041	0.145	1.181	0.002	0.179	0.856	0.003	0.063	0.825	0.042
Average of ND per week	0.414	0.793	<0.001	0.422	0.657	<0.001	0.497	0.476	<0.001	0.152	0.459	0.023
Sleep onset time on ND	0.141	1.109	<0.001	0.019	0.919	0.040	0.054	0.666	0.041	0.065	0.641	0.013
Sleeping hour on ND	-0.159	0.939	0.005	-0.127	0.778	0.003	-0.344	0.564	<0.001	-0.434	0.544	<0.001
	F=50.581, P<0.001, R²=0.560, adjusted R²=0.549			F=24.369, P<0.001, R²=0.380, adjusted R²=0.364			F=168.548, P<0.001, R²= 0.809, adjusted R²=0.804			F=24.803, P<0.001, R²=0.384, adjusted R²=0.369

Abbreviations: ND, night duty (emergency room duty included); β, standardized regression coefficient; SE, standard error. Values are presented as standardized regression coefficient, standard error and P value. Calculated by multiple linear regression analyses adjusted by gender, age, marital status, education, department and smoking.

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