High prevalence of depression and sleep–wake disorders among female emergency medicine residents in South Korea

Figures & data

Figure 1. Annual census and gender ratio of emergency medicine residents in South Korea.

Table 1. General characteristics of survey respondents by gender.

	Overall (n = 382)	Female resident (n = 60, 15.7%)	Male resident (n = 322, 84.3%)	p-Value*
Age^†	30.0 (28.0–34.0)	30.0 (28.8–33.3)	30.0 (28.0–34.0)	.603
Marital status				.948
Single	237 (62.0)	37 (61.7)	200 (62.1)
Married	145 (38.0)	23 (38.3)	122 (37.9)
Level of residency				.745
R1	94 (24.6)	18 (30.0)	76 (23.6)
R2	93 (24.3)	14 (23.3)	79 (24.5)
R3	96 (25.1)	13 (21.7)	83 (25.8)
R4	99 (25.9)	15 (25.0)	84 (26.1)
Level of training EMC				<.001
Level 1 (regional EMC)	188 (42.9)	17 (28.3)	171 (53.1)
Level 2 (local EMC) or others	194 (50.8)	43 (71.7)	151 (46.9)
History of taking medicines
TCA, BZP, narcotics	50 (13.1)	12 (20.0)	38 (11.8)	.084
Sleep aids, zolpidem	67 (17.5)	12 (20.0)	55 (17.1)	.585
Caffeine during night duty	330 (86.4)	54 (90.0)	276 (85.7)	.374
History of smoking	87 (22.8)	4 (6.7)	83 (25.8)	.005
History of alcohol	212 (55.5)	26 (43.3)	186 (57.8)	.114
Clinical activity^†
Weekly worked hours, total	68.0 (60.0–72.0)	72.0 (58.0–72.0)	64.0 (60.0–75.0)	.773
Monthly night duty/night shift	10.0 (8.0–12.3)	11.0 (8.8–13.0)	10.0 (8.0–12.0)	.057
Flexibility of shift trade				.009
Yes	270 (70.7)	34 (56.7)	236 (73.3)
No	112 (29.3)	26 (43.3)	86 (26.7)
Depression and life quality^†
PHQ-9 depression score	6.0 (3.0–10.0)	7.0 (3.8–12.0)	5.0 (3.0–10.0)	.004
Epworth sleepiness scale	8.0 (6.0–12.0)	11.5 (7.0–14.0)	8.0 (6.0–12.0)	.015
Apgar wellness score	5.0 (4.0–8.0)	5.0 (4.0–7.0)	5.0 (4.0–8.0)	.026

Unless otherwise indicated, data are reported as number (%) of emergency physicians.

*p‐Values reflect Mann–Whitney U tests and chi‐square comparisons where appropriate.

^†Data are reported as median (interquartile range, 25–75th percentile).

Figure 2. Gender differences in Patient Health Questionnaire (PHQ-9), Epworth sleepiness scale (ESS), and Apgar wellness scores (AWS) according to residency years. (A) Gender differences in the PHQ-9 score. For depression symptoms, PHQ-9 is >10 points. (B) Gender differences in the ESS score. An ESS score of 11 suggests the presence of excessive sleepiness. (C) Gender differences in the AWS. Individuals with AWS <5 points need professional counselling for significant trouble or pain.

Table 2. Logistic regression of predictors for depression among the survey participants.

	Grouping of variables	Depression (PHQ-9 ≥ 10) n = 105 (27.5%)	No Depression (PHQ-9 < 10) n = 277 (72.5%)	Univariate Crude Odds Ratio (95% CI)	p-Value	Multivariable Adjusted Odds Ratio (95% CI)	p-Value*
Gender	Male	82 (78.1)	240 (86.6)	Reference		1
	Female	23 (21.9)	37 (13.4)	1.82 (1.02–3.24)	.042	1.95 (1.05–3.60)	.034
Age group	<30 years old	39 (37.1)	100 (36.1)	Reference		1
	≥30 years old	66 (62.9)	177 (63.9)	0.96 (0.60–1.52)	.850	1.06 (0.64–1.77)	.801
Marital status	Single	71 (67.6)	166 (59.9)	Reference		1
	Married	34 (32.4)	111 (40.1)	0.72 (0.45–1.15)	.167	0.87 (0.51–1.48)	.611
Level of residency	R1	24 (22.9)	70 (25.3)	1.46 (0.71–2.87)	.315	1.33 (0.62–2.85)	.460
	R2	32 (30.5)	61 (22.0)	2.07 (1.08–3.97)	.028	2.00 (0.99–4.04)	.053
	R3	29 (27.6)	67 (24.2)	1.71 (0.89–3.29)	.109	1.66 (0.83–3.31)	.149
	R4	20 (19.0)	79 (28.5)	Reference		1
Training EMC	Level 1	58 (55.2)	130 (46.9)	Reference		1
	Level 2, others	47 (44.8)	147 (53.1)	0.73 (0.46–1.15)	.175	0.60 (0.37–0.96)	.035
Weekly hours worked	<70 h	58 (55.2)	156 (56.3)	Reference		1
	≥70 h	47 (44.8)	121 (43.7)	1.05 (0.67–1.64)	.849	0.68 (0.40–1.16)	.158
Monthly night duty/shift	Night duty <11	54 (51.4)	186 (97.1)	Reference		1
	Night duty ≥11	51 (48.6)	91 (32.9)	1.93 (1.22–3.05)	.005	1.97 (1.17–3.31)	.010
Flexibility of shift trade	Yes	61 (58.1)	209 (75.5)	Reference		1
	No	44 (41.9)	68 (24.5)	2.22 (1.38–3.56)	.001	2.12 (1.25–3.60)	.005

^†Adjusted by gender, age group, marital status, level of residency and training hospital, and working strength (weekly hours and monthly night duty).

Table 3. Depression, daytime sleepiness, and wellness scores in emergency medicine residents according to gender and residency training years.

	R1			R2			R3			R4
	Female	Male	p-Value*	Female	Male	p-Value*	Female	Male	p-Value*	Female	Male	p-Value*
Age	29.3 ± 2.1	29.0 ± 3.0	.349	30.1 ± 4.1	29.9 ± 3.1	.824	31.8 ± 1.6	31.8 ± 3.2	.956	33.2 ± 4.0	32.3 ± 2.9	.511
Hours worked, weekly	75.6 ± 10.3	70.9 ± 11.8	.419	62.9 ± 12.0	69.0 ± 0.7	.095	62.2 ± 8.9	64.7 ± 11.5	.442	62.1 ± 11.9	57.0 ± 11.2	.145
Night shift, monthly	10.2 ± 3.2	10.9 ± 3.3	.328	11.7 ± 1.9	10.9 ± 3.4	.280	10.7 ± 1.6	10.0 ± 3.1	.424	10.2 ± 4.8	8.7 ± 3.1	.015*
PHQ-9	7.9 ± 5.4	6.6 ± 4.6	.355	10.8 ± 6.0	7.4 ± 6.1	.042*	11.7 ± 5.3	6.9 ± 5.0	.002*	6.5 ± 5.9	5.9 ± 4.7	.822
Epworth sleepiness scale	9.9 ± 6.0	9.6 ± 5.7	.806	12.3 ± 3.3	9.6 ± 5.1	.021*	12.8 ± 3.1	9.4 ± 5.2	.026*	8.7 ± 2.7	8.5 ± 3.9	.697
Apgar wellness score	6.5 ± 1.8	5.7 ± 2.2	.094	5.4 ± 2.3	5.9 ± 2.3	.391	3.6 ± 1.4	6.1 ± 2.3	<.001*	4.8 ± 1.8	6.0 ± 2.6	.133

Unless otherwise indicated, data are reported as mean ± SD (standard deviation).

*p‐Values reflect Mann–Whitney U tests and two-way ANOVA where appropriate.

Table 4. Risk factors associated with excessive daytime sleepiness among the emergency medicine residents.

Variables overall (N = 382)	Grouping of variables	Daytime sleepiness (Epworth scale ≥11) n = 141 (36.9%)	No daytime sleepiness (Epworth scale < 11) n = 241 (63.1%)	Crude OR (95% CI)	p-Value	Adjusted OR (95% CI)	p-Value*
Gender	Male	111 (34.5)	211 (65.5)	Reference		1
	Female	30 (50.0)	30 (50.0)	1.90 (1.09–3.31)	.024	1.81 (1.01–3.26)	.049
Level of residency	R1	33 (36.3)	58 (63.7)	1.88 (0.99–3.54)	.050	1.94 (0.93–4.06)	.078
	R2	44 (47.3)	49 (52.7)	2.97 (1.59–5.51)	.001	3.13 (1.57–6.22)	.001
	R3	39 (40.6)	57 (59.4)	2.26 (1.22–4.20)	.010	2.44 (1.26–4.71)	.008
	R4	23 (23.2)	76 (76.8)	Reference		1

^†Adjusted for training hospital, working strength (weekly hours and monthly night duty), and flexibility of shift trading. To determine the logistic model calibration, we calculated the Hosmer-Lemeshow goodness of fit (p = .819). Data are represented as number (row %).

Data availability statement

The data that support the findings of this study are available on request from the corresponding author, WY. The data are not publicly available because that could compromise the privacy of research participants.