J Clin Med Res

Journal of Clinical Medicine Research, ISSN 1918-3003 print, 1918-3011 online, Open Access

Article copyright, the authors; Journal compilation copyright, J Clin Med Res and Elmer Press Inc

Journal website http://www.jocmr.org

Original Article

Volume 12, Number 7, July 2020, pages 448-453

Use of Neutrophil-to-Lymphocyte and Platelet-to-Lymphocyte Ratios in COVID-19

Figure 1. PRISMA diagram. PRISMA: Preferred Reporting Items for Systematic Reviews and Meta-Analyses.

Figure 2. NLR in severe versus non-severe COVID-19 patients. NLR: neutrophil-to-lymphocyte ratio; COVID-19: coronavirus disease 2019; SD: standard deviation; CI: confidence interval.

Figure 3. PLR in severe versus non-severe COVID-19 patients. PLR: platelet-to-lymphocyte ratio; COVID-19: coronavirus disease 2019; SD: standard deviation; CI: confidence interval.

**Table 1.** Clinical Characteristics of Included Studies
Study	Baseline characteristics	Number of patients	Study design	Age, mean/median	Female, n (%)	Comorbidities
COPD: chronic obstructive pulmonary disease.
Qin et al, 2020 [15]	Non-severe	166	Retrospective review	53	86 (51.8)	3 (1.8)	30 (18.1)	3 (1.8)	3 (1.8)	3 (1.8)	22 (13.3)	4 (2.4)	4 (2.4)
Severe	286		53	131 (45.8)	9 (3.1)	105 (36.7)	24 (8.4)	8 (2.8)	3 (1.0)	53 (18.5)	10 (3.5)	6 (2.1)
Liu et al, 2020 [16]	Non-severe	44	Prospective review	41	23 (52.3)	2 (4.5)	6 (13.6)	0 (0)	-	-	2 (4.5)	-	-
Severe	17		56	7 (41.2)	3 (17.6)	6 (35.3)	1 (5.9)	-	-	3 (17.6)	-	-
Yang et al, 2020 [17]	Non-severe	69	Retrospective review	42.1	31 (44.9)	-	7 (10.1)	4 (5.8)	-	9 (13.0)	8 (11.6)		2 (2.9)
Severe	24		57.9	6 (25)	-	16 (66.8)	9 (37.5)	-	4 (16.7)	13 (54.2)		8 (33.3)
Xia et al, 2020 [18]	Non-severe	7	Case series	54	2 (28.6)	-	1 (14)	-	-	1 (14)	-	-	-
Severe	3		61.6	2 (66.7)	-	-	-	-	-	-	-	-
Zhang et al, 2020 [19]	Non-severe	81	Retrospective review	59.3	42 (52.8)	-	-	-	-	-	-	-	-
Severe	67		60.8	29 (43.3)	-	-	-	-	-	-	-	-
Qu et al, 2020 [20]	Non-severe	27	Case series	49.4	-	-	-	-	-	-	-	-	-
Severe	3		60	-	-	-	-	-	-	-	-	-
Ye et al, 2020 [21]	Survivor	297	Retrospective review	60	160 (53.9)	-	73 (24.6)	-	-	-	41 (13.8)	-	-
Non-survivor	52		69	16 (30.8)	-	30 (57.7)	-	-	-	16 (30.8)	-	-
Zhang et al, 2020 [22]	Non-severe	84	Retrospective review	44	55 (65.5)	-	-	-	-	-	-	-	-
Severe	31		64.6	11 (35.5)	-	-	-	-	-	-	-	-
Sun et al, 2020 [23]	Non-severe	89	Retrospective review	47	47 (52.8)	-	-	-	-	-	-	-	-
Severe	27		62	9 (33.3)	-	-	-	-	-	-	-	-
Song et al, 2020 [24]	Non-severe	31	Retrospective review	48	30 (71.4)	1 (3.2)	4 (12.9)	1 (3.2)	-	3 (9.7)	2 (6.5)	-	-
Severe	42		55.5	12 (28.6)	2 (4.8)	22 (52.4)	4 (9.5)	-	1 (2.4)	4 (9.5)	-	-
Gong et al, 2020 [25]	Non-severe	161	Retrospective review	45	89 (55.3)	-	-	-	-	-	-	-	-
Severe	28		63.5	12 (42.9)	-	-	-	-	-	-	-	-
Ma et al, 2020 [26]	Non-severe	17	Retrospective review	61	7 (41.1)	-	-	-	-	-	-	17 (100)	-
Severe	20		65.5	10 (50)	-	-	-	-	-	-	20 (100)	-
Wei et al, 2020 [27]	Non-severe	137	Did not mention	40.83	62 (45.3)	2 (1.5)	-	17 (12.4)	2 (1.5)	-	4 (2.9)	-	-
Severe	30		49.03	10 (33.3)	2 (6.7)	-	7 (23.3)	0	-	7 (23.3)	-	-
Zhang et al, 2020 [28]	Recovered	50	Retrospective review	62.6	14 (28)	4 (8)	18 (36)	11 (22)	4 (8)		5 (10)	-	-
Death	10		70.6	3 (30)	2 (20)	4 (40)	3 (30)	2 (20)		4 (40)	-	-
Zhu et al, 2020 [29]	Non-severe	111	Retrospective review	50	38 (34.2)	4 (3.6)	23 (20.7)	4 (3.6)		5 (4.5)	10 (9)	4 (3.6)	-
Severe	16		57.5	7 (43.8)	2 (12.5)	8 (50)	2 (12.5)		2 (12.5)	0	1 (6.25)	-
Zhang et al, 2020 [30]	Survivors	268	Case-control studies	56	131 (48.9)	3 (1.12)	64 (23.9)	30 (11.2)	7 (2.6)	7 (2.6)	34 (12.7)	8 (3)	2 (0.8)
Non-survivors	47		66	9 (19.1)	0	14 (29.8)	5 (10.6)	0	2 (4.3)	7 (14.9)	4 (8.5)	0
Liu et al, 2020 [31]	Non-severe	43	Retrospective review	55	17 (39.5)	0	13 (30.2)	0	4 (9.3)	1 (2.3)	2 (4.7)	0	-
Severe	79		65	33 (41.8)	2 (2.5)	37 (46.8)	2 (2.5)	6 (7.6)	2 (2.5)	13 (16.5)	1 (1.3)	-
Ma et al, 2020 [32]	Non-severe	572	Retrospective review	44	273 (47.7)	-	90 (15.7)	-	-	-	29 (5.1)	-	-
Severe	63		53.3	34 (54)	-	15 (24)	-	-	-	6 (10)	-	-
Cheng et al, 2020 [33]	Survivors	67	Retrospective review	70.6	45 (67.2)	7 (10.4)	39 (58.2)	11 (16.4)		1 (1.5)	11 (16.4)	2 (3)	3 (4.5)
Non-survivors	51		73.1	20 (39.2)	6 (11.8)	25 (49)	12 (23.5)		0	16 (31.4)	0	3 (5.9)
Chen et al, 2020 [34]	Non-severe	241	Retrospective review	42.1	123	5 (2.1)	20 (8.3)	7 (3)	5 (2.1)	13 (5.4)	15 (6.2)	2 (0.8)	1 (0.4)
Severe	50		60.5	23 (46)	5 (10)	19 (38)	5 (10)	3 (6)	2 (4)	7 (14)	0	1 (2)

Table 1. Clinical Characteristics of Included Studies

Study

Baseline characteristics

Number of patients

Study design

Age, mean/median

Female, n (%)

Comorbidities

COPD

Hypertension

Cardiovascular

Cerebrovascular

Chronic liver disease

Diabetes mellitus

Cancer

Chronic kidney disease

COPD: chronic obstructive pulmonary disease.

Qin et al, 2020 [15]

Non-severe

166

Retrospective review

86 (51.8)

3 (1.8)

30 (18.1)

3 (1.8)

22 (13.3)

4 (2.4)

Severe

286

131 (45.8)

9 (3.1)

105 (36.7)

24 (8.4)

8 (2.8)

3 (1.0)

53 (18.5)

10 (3.5)

6 (2.1)

Liu et al, 2020 [16]

Non-severe

Prospective review

23 (52.3)

2 (4.5)

6 (13.6)

0 (0)

2 (4.5)

Severe

7 (41.2)

3 (17.6)

6 (35.3)

1 (5.9)

3 (17.6)

Yang et al, 2020 [17]

Non-severe

Retrospective review

42.1

31 (44.9)

7 (10.1)

4 (5.8)

9 (13.0)

8 (11.6)

2 (2.9)

Severe

57.9

6 (25)

16 (66.8)

9 (37.5)

4 (16.7)

13 (54.2)

8 (33.3)

Xia et al, 2020 [18]

Non-severe

Case series

2 (28.6)

1 (14)

Severe

61.6

2 (66.7)

Zhang et al, 2020 [19]

Non-severe

Retrospective review

59.3

42 (52.8)

Severe

60.8

29 (43.3)

Qu et al, 2020 [20]

Non-severe

Case series

49.4

Severe

Ye et al, 2020 [21]

Survivor

297

Retrospective review

160 (53.9)

73 (24.6)

41 (13.8)

Non-survivor

16 (30.8)

30 (57.7)

16 (30.8)

Zhang et al, 2020 [22]

Non-severe

Retrospective review

55 (65.5)

Severe

64.6

11 (35.5)

Sun et al, 2020 [23]

Non-severe

Retrospective review

47 (52.8)

Severe

9 (33.3)

Song et al, 2020 [24]

Non-severe

Retrospective review

30 (71.4)

1 (3.2)

4 (12.9)

1 (3.2)

3 (9.7)

2 (6.5)

Severe

55.5

12 (28.6)

2 (4.8)

22 (52.4)

4 (9.5)

1 (2.4)

4 (9.5)

Gong et al, 2020 [25]

Non-severe

161

Retrospective review

89 (55.3)

Severe

63.5

12 (42.9)

Ma et al, 2020 [26]

Non-severe

Retrospective review

7 (41.1)

17 (100)

Severe

65.5

10 (50)

20 (100)

Wei et al, 2020 [27]

Non-severe

137

Did not mention

40.83

62 (45.3)

2 (1.5)

17 (12.4)

2 (1.5)

4 (2.9)

Severe

49.03

10 (33.3)

2 (6.7)

7 (23.3)

Zhang et al, 2020 [28]

Recovered

Retrospective review

62.6

14 (28)

4 (8)

18 (36)

11 (22)

4 (8)

5 (10)

Death

70.6

3 (30)

2 (20)

4 (40)

3 (30)

2 (20)

4 (40)

Zhu et al, 2020 [29]

Non-severe

111

Retrospective review

38 (34.2)

4 (3.6)

23 (20.7)

4 (3.6)

5 (4.5)

10 (9)

4 (3.6)

Severe

57.5

7 (43.8)

2 (12.5)

8 (50)

2 (12.5)

1 (6.25)

Zhang et al, 2020 [30]

Survivors

268

Case-control studies

131 (48.9)

3 (1.12)

64 (23.9)

30 (11.2)

7 (2.6)

34 (12.7)

8 (3)

2 (0.8)

Non-survivors

9 (19.1)

14 (29.8)

5 (10.6)

2 (4.3)

7 (14.9)

4 (8.5)

Liu et al, 2020 [31]

Non-severe

Retrospective review

17 (39.5)

13 (30.2)

4 (9.3)

1 (2.3)

2 (4.7)

Severe

33 (41.8)

2 (2.5)

37 (46.8)

2 (2.5)

6 (7.6)

2 (2.5)

13 (16.5)

1 (1.3)

Ma et al, 2020 [32]

Non-severe

572

Retrospective review

273 (47.7)

90 (15.7)

29 (5.1)

Severe

53.3

34 (54)

15 (24)

6 (10)

Cheng et al, 2020 [33]

Survivors

Retrospective review

70.6

45 (67.2)

7 (10.4)

39 (58.2)

11 (16.4)

1 (1.5)

11 (16.4)

2 (3)

3 (4.5)

Non-survivors

73.1

20 (39.2)

6 (11.8)

25 (49)

12 (23.5)

16 (31.4)

3 (5.9)

Chen et al, 2020 [34]

Non-severe

241

Retrospective review

42.1

123

5 (2.1)

20 (8.3)

7 (3)

5 (2.1)

13 (5.4)

15 (6.2)

2 (0.8)

1 (0.4)

Severe

60.5

23 (46)

5 (10)

19 (38)

5 (10)

3 (6)

2 (4)

7 (14)

1 (2)