Long-term psychological outcomes among frontline healthcare workers following the COVID-19 pandemic: A systematic review

Table 1 Inclusion and exclusion criteria

Inclusion	Exclusion
Published in English	All languages other than English
Data collected on or after March 1, 2023	Data collected before March 1, 2023
All or part of the analyses targeted FL HCWs caring for patients with COVID-19: Physicians, nurses, advanced practice providers	Reports limited to the context of another pandemic (e.g., Middle East Respiratory Syndrome, influenza) or event (e.g., earthquake or another natural event) not related to the COVID-19 pandemic
Reporting quantitative data (e.g., prevalence rates) on psychological problems experienced by FL HCWs after the COVID-19 pandemic	Reports limited to other professionals not working in the health system (i.e., police officers, firefighters, teachers) or healthcare students
Reporting quantitative data (e.g., prevalence rates) on psychological problems (i.e., depressive symptoms, anxiety symptoms, insomnia, posttraumatic stress disorder symptoms) and other psychological data, including burnout symptoms, sleep problems, psychological stress and distress)	Reports limited to HCWs who did not perform hospital-based work as a member of the primary healthcare team on hospitalized COVID-19 patients (i.e., dentists, orthopedic surgeons)
	Reports limited to types of qualitative data other than prevalence rates or results of interventional studies
	Reports limited to data on emotions (e.g., fear) or behaviors (e.g., physical activity, smoking)
	Reports limited to surges of COVID-19 infection occurring locally at time of study (i.e., several provinces in China had surges in early 2023; studies reporting data collection during these surges were excluded)

FL HCW: Frontline healthcare workers; COVID-19: Coronavirus disease 2019.

Table 2 Study characteristics, n (%)/mean ± SD

Ref.	Country	Survey year	Occupation	Comparison	Number of participants	Age (mean ± SD or most common age group)	Men	Depression screen	Anxiety screen	PTSD screen	Sleep screen	Distress screen
Azoulay et al[10]	Europe	2024	ICU HCWs	None	850	39 ± 7	276 (32)	Yes	Yes	No	No	Yes
Cheng et al[11]	Taiwan	2023	Nurse practitioners	None	98	35-44	3 (3.1)	Yes	Yes	No	No	Yes
Yang et al[12]	China	2023	Nurses	None	2,065	26-35	370 (17.9)	Yes	Yes	No	Yes	No
Qian et al[13]	China	2023	HCWs	FL vs NFL	1419	26-35	343 (24.2)	No	No	No	No	Yes
Mohr et al[14]	United States	2018-2023	HCWs	Year; FL vs NFL	293164	46.3 ± 12.1	83258 (28.4)	No	No	No	No	Yes
Liu et al[15]	China	2023	HCWs	None	2070	25-34	469 (22.7)	Yes	Yes	Yes	Yes	No
Wen et al[16]	China	2022, 2023	Nurses, physicians	Year; ICU	2292	31-40	389 (17.0)	No	No	Yes	No	No
Narita et al[17]	Japan	2023	HCWs	FL vs NFL	660	42.7 ± 10.9	214 (32.4)	No	No	Yes	No	No
Liu et al[18]	China	2023	Nurses	Year	784	NR	366 (49.6)	Yes	Yes	No	Yes	No
Giménez-Díez et al[19]	Spain	2023	Nurses	Year; FL vs NFL	1045	42.7 ± 10.9	128 (12.2)	Yes	Yes	Yes	Yes	No
Xu et al[20]	China	2023	Nurses, physicians	None	2094	< 35	517 (24.7)	Yes	Yes	No	No	Yes
Xie et al[21]	China	2023	Nurses	FL vs NFL	253	18-45	22 (8.7)	Yes	Yes	No	Yes	No
Wang et al, 2023[22]	China	2023	Nurses	None	2210	26-35	436 (19.7)	Yes	Yes	No	No	No
Zhang et al[23]	China	2023	Nurses	FL vs NFL	2513	25-44	98 (3.9)	No	No	Yes	No	Yes
Wang et al, 2024[24]	China	2023	Nurses	None	2210	26-35	436 (19.7)	No	No	No	No	Yes
Ding et al[25]	China	2023	HCWs	FL vs NFL	1412	18-34	609 (43.1)	Yes	Yes	No	Yes	No
Yang et al[26]	China	2022, 2023	Nurses	Year	816	NR	381 (49.9)	Yes	Yes	No	Yes	No
Çerçizaj et al[27]	Albania	2024	Nurses	FL vs NFL	288	38.6 ± 10.4	52 (17.9)	Yes	Yes	No	No	Yes
Hoseini-Marvast et al[28]	Iran	2023	Nurses	FL vs NFL	890	34.89 ± 7.84	107 (12.0)	Yes	Yes	No	No	No

FL HCW: Frontline healthcare workers; ICU: Intensive care unit; NFL: Non-frontline; NR: Not report; PTSD: Posttraumatic stress disorder.

Table 3 Depression data, n (%)/mean ± SD

Ref.	Depression screening tool	Positive depression screen definition	Depression prevalence	Depression survey score	Results of comparison
Azoulay et al[10]	HADS	7 of 21 on the depression subscale	219 (26)	Mean NR; median 4 (IQR: 2-7)	NCG
Cheng et al[11]	DASS-21	> 9	NR	8.2 ± 6.9	NCG
Yang et al[12]	SDS	≥ 40	NR	53.6 ± 13.1	NCG
Hoseini-Marvast et al[28]	Beck-2	Minimal 0-7, mild 8-15, moderate 16-25, severe 26-63	845 (50)	20.8 ± 13.7	Not significant for comparison between FL vs NFL (data NR)
Çerçizaj et al[27]	DASS-21	Mild 10-13, moderate 14-20, severe 21-27, extremely severe ≥ 28	Mild 16 (5.6); moderate 11 (3.8); severe/extremely severe 9 (3.1)	NR	OR 2.67 (95%CI: 1.2-6.1) for FL vs NFL
Liu et al[15]	PHQ-9	≥ 5	865 (41.8) (95%CI: 39.7-43.9)	NR	NCG
Yang et al[26]	SDS	≥ 40	NR	55.4 ± 12.8	Mean 62.46 ± 4.69 in 2022 vs 55.4 ± 12.8 in 2023, P < 0.001
Ding et al[25]	PHQ-9	≥ 10	231 (16.4)	NR	OR 1.66 (95%CI: 1.47-1.9) P < 0.001 for FL vs NFL
Liu et al[18]	SDS	≥ 73 for severe depression	36 (4.9)	55.6 ± 12.6	Prevalence 36 (4.9) in 2023 vs 13 (1.7) in 2022, P < 0.001
Giménez-Díez et al[19]	PHQ-9	Pooled symptom profile	191 (73.9)	8.9 ± 5.9	OR = 1.38 (95%CI: 1.00-1.90), P = 0.048 FL vs NFL
Xu et al[20]	CES-D	Pooled symptom profile	1300 (62.1) low, 605 (28.9) moderate and 189 (9) high	NR	NCG
Xie et al[21]	SDS	≥ 50	137 (64.9)	NR	OR = 1.44 (95%CI: 0.39-1.25), P = 0.017 FL vs NFL
Wang et al[22]	SDS	≥ 50	NR	54.3 ± 9.4	NCG

NCG: Bo comparison group; NR: Not reported; NS: Not significant; SDS: Self-Rating Depression Scale; PHQ-9: Patient Health Questionnaire-9; DASS-21: Depression Anxiety Stress Scale-21; HADS: Hospital Anxiety and Depression Scale; Beck-2: Beck depression inventory 2; CES-D: Center for Epidemiologic Studies Depression Scale; FL: Frontline; NFL: Non frontline; OR: Odds ratio; NR: Not report; IQR: Interquartile range.

Table 4 Anxiety data, n (%)/mean ± SD

Ref.	Anxiety screening tool	Positive anxiety screen cutoff	Estimated anxiety prevalence	Anxiety survey score	Results of comparison
Azoulay et al[10]	HADS	≥ 7	492 (58)	median score 7 (IQR 5-10)	NCG
Cheng et al[11]	DASS-21	> 7	NR	6.92 ± 6.32	NCG
Yang et al[12]	SAS	≥ 50	NR	49.62 ± 11.9	NCG
Liu et al[12]	GAD-7	≥ 5	638 (30.8) (95%CI: 28.8-32.8)	NR	NCG
Liu et al[18]	SAS	NR	NR	51.5 ± 12.2	Mean SAS 69.6 ± 5.04 in 2022 vs in 51.5 ± 12.2 in 2023, P < 0.001
Giménez-Díez et al[19]	GAD-7	Dichotomous MH variable (no/mild vs moderate/severe); GAD-7 cutoff not provided	839 (80.3)	9.4 ± 5.7	OR for FL vs NFL 1.38 (95%CI: 1.00-1.90)
Xu et al[20]	GAD-7	Psychological symptom profile created: Low, moderate, and high level	1300 (62.1) low, 605 (28.9) moderate, and 189 (9) high	NR	NCG
Xie et al[21]	GAD-7	≥ 5	120 (56.9)	NR	OR = 0.67 (95%CI: 0.36-1.24), P = 0.20
Wang et al[22], 2023	SAS	≥ 36	1438 (65.1)	NR	NCG
Ding et al[25]	GAD-7	≥ 10	254 (18)	NR	OR for FL vs NFL 2.047 (95%CI: 1.68-2.24), P < 0.001
Yang et al[26]	SAS	≥ 50	61 (8.0)	51.4 ± 12.2	426 (52.3) in 2022 vs 61 (8.0) in 2023, P < 0.001
Çerçizaj et al[27]	DASS-21	Normal 0-7, mild 8-9, moderate 10-14, severe 15-19, extremely severe 20+	Mild 9 (3.1), moderate 25 (8.7), severe 3 (1), extremely severe 9 (3.1)	NR	OR for FL vs NFL 4.17 (95%CI: 1.6-10.6), P = 0.003
Hoseini-Marvast et al[28]	Beck anxiety inventory	Low 0-13, mild 14-19, moderate 20-28, severe 29-63	579 (65)	22 ± 13.4	NS FL vs NFL (data NR)

NCG: No comparison group; NR: Not reported; NS: Not significant; FL: Frontline; NFL: Non frontline; GAD-7: Generalized Anxiety Disorder-7; SAS: Zung Self-rating Anxiety Scale; OR: Odds ratio.

Table 5 Sleep disorder data, n (%)

Ref.	Sleep screening tool	Positive sleep screen definition	Sleep prevalence in FL 2023	mean ± SD	Results of comparison
Yang et al[12]	PSQI	≥ 8	1088 (52.70)	10.11 ± 4.2	NCG
Liu et al[15]	ISI	≥ 8	782 (34.3) (95%CI: 32.2-36.3)	NR	NCG
Liu et al[18]	PSQI	≥ 8	NR	9.4 ± 4.7	10.7 ± 2.5 in 2022 and 9.4 ± 4.7 in 2023, P < 0.001
Giménez-Díez et al[19]	ISI	NR	698 (66.80)	10.8 ± 6.4	NR
Xie et al[21]	PSQI	≥ 7	201 (79.4)	NR	NR
Ding et al[25]	ISI	≥ 15	289 (20.5)	NR	OR for FL vs NFL 1.09 (95%CI: 1.02-1.16), P = 0.01
Yang et al[26]	PSQI	≥ 8	NR	9.3 ± 4.7	10.7 ± 2.5 in 2022 vs 9.3 ± 4.7 in 2023, P < 0.001

PSQI: Pittsburgh Sleep Quality Index; ISI: Insomnia severity index; NCG: No comparison group; NR: Not reported; NS: Not significant; FL: Frontline; NFL: Non frontline; OR: Odds ratio.

Table 6 Distress and turnover intention table, n (%)/mean ± SD

Ref.	Distress screening tool	Distress screen definition	Distress prevalence in FL 2023	mean ± SD	Results of comparison
Azoulay et al[10]	VAS and intention to leave yes/no	NR	Intention to leave 484 (57); VAS NR	NR	NCG
Cheng et al[11]	DASS-21 and Stress Scale of Caring for Patients with Highly-Infectious Disease	> 14	NR	DASS-21 stress score 1324 ± 8.14; HSS 48.89 ± 18.5	NCG
Qian et al[13]	IES-R; change in work stress and rest time yes/no	NR	NR	IES-R score 173 ± 12.7	NS increase in work stress and decrease in rest time reported in FL vs NFL
Mohr et al[14]	2 items from MBI and coronavirus disease 2019 professional stress	Burnout ≥ once per week; coronavirus disease 2019 professional stress positive if answered high or extreme stress	95278 (32.50)		ICU had highest work stress at the start of the pandemic (48.6%) with the greater decline (12.9%) from 2020-2023 than other work areas
Xu et al[20]	MBI	Psychological symptom profile created: Low, moderate, and high level	1300 (62.1) low level, 605 (28.9) moderate level, and 189 (9) high level	NR	NCG
Zhang et al[23]	Turnover Intention Scale	< 6 very low; 6-12 low; 13-18 high; > 19 very high	High turnover intention 804 (32) and very high 302 (12)	NR	FL 2.09 ± 0.88 vs NFL 1.85 ± 1.85, P < 0.01
Wang et al[24]	MBI-HSS	> 26 in EE, > 9 in D, and < 33 in PA	1666 (75.38)	NR	NCG
Çerçizaj et al[27]	DASS-21	Normal 0-14, mild 15-18, moderate 19-25, severe 26-33, extremely severe ≥ 34	Mild 3 (1.0), Moderate 0 (0), severe or extremely severe 0 (0)	NR	NR

VAS: Visual analog scale; IES-R: Impact of Event Scale-Revised; MBI: Maslach Burnout Inventory; HSS: Health Services Scale; DASS-21: Depression Anxiety Stress Scale-21; NCG: No comparison group; NR: Not reported; NS: Not significant; FL: Frontline; NFL: Non frontline; OR: Odds ratio; ICU: Intensive care unit; EE: Emotional Exhaustion; D: Depersonalization; PA: Personal accomplishment.