J Hematol

Journal of Hematology, ISSN 1927-1212 print, 1927-1220 online, Open Access

Article copyright, the authors; Journal compilation copyright, J Hematol and Elmer Press Inc

Journal website https://www.thejh.org

Original Article

Volume 10, Number 3, June 2021, pages 98-105

Does ABO Blood Groups Affect Outcomes in Hospitalized COVID-19 Patients?

**Table 1.** Demographical and Clinical Characteristics of COVID-19 Patients According to ABO Groups
	A	B	AB	O	P
COVID-19: coronavirus disease 2019; IQR: interquartile range; BMI: body mass index; COPD: chronic obstructive pulmonary disease; ESRD: end-stage renal disease; VTE: venous thromboembolism; ACEI: angiotensin-converting enzyme inhibitor.
Total	1,301	377	133	1,752
Age, median (IQR)	67 (54 - 77)	67 (52 - 78)	68 (53 - 77)	66 (52 - 76)	0.20
Male (%)	53.8	52.8	54.9	50.3	0.23
Race (%)					< 0.001
White	81.8	58.4	68.4	67.4
Blacks	5	18.6	15.0	8.3
Hispanics	10.8	13.5	9.0	20.5
Asians/Pacific Islander	1.1	5.8	2.2	1.3
Not answered	1.4	3.7	5.3	2.5
Rh positive	89.5	89.4	88.7	91.2	0.33
BMI	30.3	30.6	29.7	30.2	0.58
Comorbidities (%)
Hypertension	74.6	76.4	69.9	72.1	0.17
Congestive heart failure	33.2	39.5	33.8	35.1	0.15
Diabetes mellitus	48.7	49.1	45.1	45.0	0.17
COPD	38.5	38.9	32.3	37.7	0.54
ESRD	3.6	3.2	5.3	6.3	0.003
Cirrhosis	13.1	13.0	15.8	12.8	0.81
Cancer	14.6	12.2	12.0	13.8	0.58
VTE	8.1	7.7	11.3	5.2	0.002
Medications
Anticoagulation	14.1	13.5	15.0	12.9	0.73
Aspirin	17.9	16.7	18.1	16.8	0.86
ACEI	30.6	28.1	30.8	29.0	0.7
Statins	33.6	30.2	26.5	30.6	0.16
COVID-19 medications (%)
Hydroxychloroquine	3.3	4.5	5.3	4.3	0.42
Tocilizumab	6.6	9.3	6.0	7.8	0.28
Steroids	71.2	74.8	80.4	68.8	0.006
Convalescent plasma	37.9	35.5	43.6	35	0.11
Remdesivir	60.9	61.5	63.2	55.1	0.003
Anticoagulation					0.08
Standard	54.8	53.1	53.4	54.3
High	33.6	33.4	39.9	31.6
4C score	11 (7 - 14)	11 (7 - 14)	11 (7 - 13)	11 (7 - 14)	0.47

Table 1. Demographical and Clinical Characteristics of COVID-19 Patients According to ABO Groups

COVID-19: coronavirus disease 2019; IQR: interquartile range; BMI: body mass index; COPD: chronic obstructive pulmonary disease; ESRD: end-stage renal disease; VTE: venous thromboembolism; ACEI: angiotensin-converting enzyme inhibitor.

Total

1,301

377

133

1,752

Age, median (IQR)

67 (54 - 77)

67 (52 - 78)

68 (53 - 77)

66 (52 - 76)

0.20

Male (%)

53.8

52.8

54.9

50.3

0.23

Race (%)

< 0.001

White

81.8

58.4

68.4

67.4

Blacks

18.6

15.0

8.3

Hispanics

10.8

13.5

9.0

20.5

Asians/Pacific Islander

1.1

5.8

2.2

1.3

Not answered

1.4

3.7

5.3

2.5

Rh positive

89.5

89.4

88.7

91.2

0.33

BMI

30.3

30.6

29.7

30.2

0.58

Comorbidities (%)

Hypertension

74.6

76.4

69.9

72.1

0.17

Congestive heart failure

33.2

39.5

33.8

35.1

0.15

Diabetes mellitus

48.7

49.1

45.1

45.0

0.17

COPD

38.5

38.9

32.3

37.7

0.54

ESRD

3.6

3.2

5.3

6.3

0.003

Cirrhosis

13.1

13.0

15.8

12.8

0.81

Cancer

14.6

12.2

12.0

13.8

0.58

VTE

8.1

7.7

11.3

5.2

0.002

Medications

Anticoagulation

14.1

13.5

15.0

12.9

0.73

Aspirin

17.9

16.7

18.1

16.8

0.86

ACEI

30.6

28.1

30.8

29.0

0.7

Statins

33.6

30.2

26.5

30.6

0.16

COVID-19 medications (%)

Hydroxychloroquine

3.3

4.5

5.3

4.3

0.42

Tocilizumab

6.6

9.3

6.0

7.8

0.28

Steroids

71.2

74.8

80.4

68.8

0.006

Convalescent plasma

37.9

35.5

43.6

0.11

Remdesivir

60.9

61.5

63.2

55.1

0.003

Anticoagulation

0.08

Standard

54.8

53.1

53.4

54.3

High

33.6

33.4

39.9

31.6

4C score

11 (7 - 14)

11 (7 - 13)

11 (7 - 14)

0.47

**Table 2.** Clinical Features of ICU Admissions in COVID-19 Patients According to ABO Groups
	A	B	AB	O	P
ICU: intensive care unit; COVID-19: coronavirus disease 2019; IQR: interquartile range.
ICU transfers, n	394	122	39	589	0.23
Use of mechanical ventilation, n (%)	193 (48.9)	74 (60.8)	22 (56.4)	354 (60.1)	0.005
Length of mechanical ventilation (in days), median (IQR)	7 (2 - 16)	9.5 (2 - 20)	10 (2 - 22)	6 (2 - 16)	0.59
Paralytic use (%)	35.2	31.1	22.7	35.9	0.56
Inhaled vasodilator (%)	13.5	9.5	0	12.4	0.27
Tracheostomy (%)	14.5	20.3	36.4	14.4	0.03
Use of vasopressors (%)
Required norepinephrine	48.2	59.8	48.7	55.9	0.045
Required vasopressin	24.6	34.4	17.9	30.4	0.04
Required epinephrine	9.9	15.6	7.7	14.9	0.07
Any vasopressor	48.2	60.7	48.7	56.0	0.03

Table 2. Clinical Features of ICU Admissions in COVID-19 Patients According to ABO Groups

ICU: intensive care unit; COVID-19: coronavirus disease 2019; IQR: interquartile range.

ICU transfers, n

394

122

589

0.23

Use of mechanical ventilation, n (%)

193 (48.9)

74 (60.8)

22 (56.4)

354 (60.1)

0.005

Length of mechanical ventilation (in days), median (IQR)

7 (2 - 16)

9.5 (2 - 20)

10 (2 - 22)

6 (2 - 16)

0.59

Paralytic use (%)

35.2

31.1

22.7

35.9

0.56

Inhaled vasodilator (%)

13.5

9.5

12.4

0.27

Tracheostomy (%)

14.5

20.3

36.4

14.4

0.03

Use of vasopressors (%)

Required norepinephrine

48.2

59.8

48.7

55.9

0.045

Required vasopressin

24.6

34.4

17.9

30.4

0.04

Required epinephrine

9.9

15.6

7.7

14.9

0.07

Any vasopressor

48.2

60.7

48.7

56.0

0.03

**Table 3.** Outcomes of Hospitalized COVID-19 Patients According to ABO Groups
	A	B	AB	O	P
COVID-19: coronavirus disease 2019; IQR: interquartile range; LOS: length of stay; ICH: intracerebral hemorrhage; SNF: skilled nursing facility; LTAC: long-term acute care; HAI: health care-associated infection.
Outcomes
In-hospital mortality (%)	17.5	20.4	11.3	20.1	0.03
28-day mortality (%)	16.4	18.6	9.6	18.8	0.04
LOS in survivors (in days), median (IQR)	5 (3 - 11)	6 (4 - 12)	6 (3 - 15)	6 (3 - 11)	0.09
Time to death (in days), median (IQR)	14 (7 - 24)	14 (8.5 - 27.5)	24 (8 - 39)	14 (7 - 22)	0.52
Disposition (%)					0.20
Home	62.0	62.4	54.7	63.4
Home with health	20.9	20.0	22.2	19.5
Rehab/SNF/LTAC/acute care	15	15.6	17.1	13.7
Others	2.1	2.0	6	3.5
Readmission	16.4	17.3	17.8	16.3	0.95
Complications (%)
Acute stroke	2.3	4.0	5.3	2.7	0.11
Acute ICH	1.1	2.7	1.5	1.2	0.14
Acute kidney injury	18.2	19.9	18.8	21.9	0.09
Acute kidney injury requiring hemodialysis	3.1	2.6	1.5	4.5	0.19
Acute VTE	5.7	6.9	12.0	6.6	0.04
Blood transfusion	11.7	13.5	15.0	15.8	0.01
HAI	4.3	5.0	4.5	6.1	0.17

Table 3. Outcomes of Hospitalized COVID-19 Patients According to ABO Groups

COVID-19: coronavirus disease 2019; IQR: interquartile range; LOS: length of stay; ICH: intracerebral hemorrhage; SNF: skilled nursing facility; LTAC: long-term acute care; HAI: health care-associated infection.

Outcomes

In-hospital mortality (%)

17.5

20.4

11.3

20.1

0.03

28-day mortality (%)

16.4

18.6

9.6

18.8

0.04

LOS in survivors (in days), median (IQR)

5 (3 - 11)

6 (4 - 12)

6 (3 - 15)

6 (3 - 11)

0.09

Time to death (in days), median (IQR)

14 (7 - 24)

14 (8.5 - 27.5)

24 (8 - 39)

14 (7 - 22)

0.52

Disposition (%)

0.20

Home

62.0

62.4

54.7

63.4

Home with health

20.9

20.0

22.2

19.5

Rehab/SNF/LTAC/acute care

15.6

17.1

13.7

Others

2.1

2.0

3.5

Readmission

16.4

17.3

17.8

16.3

0.95

Complications (%)

Acute stroke

2.3

4.0

5.3

2.7

0.11

Acute ICH

1.1

2.7

1.5

1.2

0.14

Acute kidney injury

18.2

19.9

18.8

21.9

0.09

Acute kidney injury requiring hemodialysis

3.1

2.6

1.5

4.5

0.19

Acute VTE

5.7

6.9

12.0

6.6

0.04

Blood transfusion

11.7

13.5

15.0

15.8

0.01

HAI

4.3

5.0

4.5

6.1

0.17

**Table 4.** Inflammatory Markers in COVID-19 Patients According to ABO Groups
Inflammatory markers^a	A	B	AB	O	P
^aMedian (IQR), total samples. COVID-19: coronavirus disease 2019; CRP: C-reactive protein; LDH: lactate dehydrogenase.
Initial ferritin	436 (194 - 868)	456 (223 - 954)	544 (253 - 945)	457 (209 - 987)	0.13
Initial CRP	8 (3 - 13)	8 (4 - 14)	8 (5 - 14)	8 (4 - 14)	0.36
Initial LDH	318 (240 - 425)	334 (261 - 471)	352 (251 - 432)	324 (244 - 441)	0.15
Initial D-dimer	0.9 (0.5 - 1.7)	0.9 (0.5 - 1.8)	0.8 (0.5 - 1.5)	1 (0.6 - 1.9)	0.09
Initial fibrinogen	545 (431 - 682)	559 (453 - 657)	542 (414 - 704)	543 (423 - 695)	0.93
Highest ferritin	551 (1,081 - 1,060)	574 (273 - 1,182)	696 (304 - 1,210)	614 (267 - 1,260)	0.04
Highest CRP	9 (4 - 15)	10 (5 - 16)	10 (6 - 16)	10 (5 - 16)	0.39
Highest LDH	346 (256 - 471)	375 (277 - 521)	370 (268 - 458)	350 (263 - 504)	0.09
Highest D-dimer	1.2 (0.7 - 4)	1.3 (0.7 - 4)	1.2 (0.6 - 4)	1.4 (0.8 - 4)	0.06
Highest fibrinogen	574 (459 - 721)	599 (453 - 725)	572 (440 - 738)	574 (453 - 725)	0.93

Table 4. Inflammatory Markers in COVID-19 Patients According to ABO Groups

Inflammatory markers^a

^aMedian (IQR), total samples. COVID-19: coronavirus disease 2019; CRP: C-reactive protein; LDH: lactate dehydrogenase.

Initial ferritin

436 (194 - 868)

456 (223 - 954)

544 (253 - 945)

457 (209 - 987)

0.13

Initial CRP

8 (3 - 13)

8 (4 - 14)

8 (5 - 14)

8 (4 - 14)

0.36

Initial LDH

318 (240 - 425)

334 (261 - 471)

352 (251 - 432)

324 (244 - 441)

0.15

Initial D-dimer

0.9 (0.5 - 1.7)

0.9 (0.5 - 1.8)

0.8 (0.5 - 1.5)

1 (0.6 - 1.9)

0.09

Initial fibrinogen

545 (431 - 682)

559 (453 - 657)

542 (414 - 704)

543 (423 - 695)

0.93

Highest ferritin

551 (1,081 - 1,060)

574 (273 - 1,182)

696 (304 - 1,210)

614 (267 - 1,260)

0.04

Highest CRP

9 (4 - 15)

10 (5 - 16)

10 (6 - 16)

10 (5 - 16)

0.39

Highest LDH

346 (256 - 471)

375 (277 - 521)

370 (268 - 458)

350 (263 - 504)

0.09

Highest D-dimer

1.2 (0.7 - 4)

1.3 (0.7 - 4)

1.2 (0.6 - 4)

1.4 (0.8 - 4)

0.06

Highest fibrinogen

574 (459 - 721)

599 (453 - 725)

572 (440 - 738)

574 (453 - 725)

0.93

**Table 5.** Comparison Between Blood Groups With Regards to Rates of ICU Transfers, AKI, Acute VTE, Mechanical Ventilation, Use of Vasopressors, In-Hospital Mortality and Readmissions in COVID-19
	B	AB	O
A is the comparison group. The regression adjusts for age, gender, race, comorbidities, clinical characteristics, inflammatory markers, 4C score and COVID-19 medications including anticoagulation status. The model was bootstrapped 2,000 times with replacement. The values shown are odds ratio (95% confidence interval), P value. ICU: intensive care unit; AKI: acute kidney injury; VTE: venous thromboembolism; COVID-19: coronavirus disease 2019.
ICU transfer	0.74 (0.49 - 1.09), 0.13	0.62 (0.33 - 1.17), 0.14	1.01 (0.79 - 1.28), 0.92
Acute kidney injury	0.83 (0.56 - 1.24), 0.37	0.66 (0.35 - 1.25), 0.20	1.01 (0.78 - 1.29), 0.93
Acute VTE	1.07 (0.63 - 1.78), 0.8	2.25 (1.18 - 4.29), 0.014	1.05 (0.75 - 1.46), 0.76
Mechanical ventilation	1.06 (0.59 - 1.90), 0.84	1.16 (0.48 - 2.79), 0.72	1.35 (0.92 - 1.99), 0.12
Pressor use	1.28 (0.72 - 2.29), 0.39	0.58 (0.21 - 1.64), 0.31	0.82 (0.57 - 1.19), 0.31
In hospital mortality	1.03 (0.66 - 1.59), 0.88	0.34 (0.12 - 0.96), 0.04	1.05 (0.79 - 1.39), 0.07
Readmission	1.12 (0.78 - 1.58), 0.54	1.39 (0.81 - 2.39), 0.22	1.04 (0.83 - 1.31), 0.71

Table 5. Comparison Between Blood Groups With Regards to Rates of ICU Transfers, AKI, Acute VTE, Mechanical Ventilation, Use of Vasopressors, In-Hospital Mortality and Readmissions in COVID-19

A is the comparison group. The regression adjusts for age, gender, race, comorbidities, clinical characteristics, inflammatory markers, 4C score and COVID-19 medications including anticoagulation status. The model was bootstrapped 2,000 times with replacement. The values shown are odds ratio (95% confidence interval), P value. ICU: intensive care unit; AKI: acute kidney injury; VTE: venous thromboembolism; COVID-19: coronavirus disease 2019.

ICU transfer

0.74 (0.49 - 1.09), 0.13

0.62 (0.33 - 1.17), 0.14

1.01 (0.79 - 1.28), 0.92

Acute kidney injury

0.83 (0.56 - 1.24), 0.37

0.66 (0.35 - 1.25), 0.20

1.01 (0.78 - 1.29), 0.93

Acute VTE

1.07 (0.63 - 1.78), 0.8

2.25 (1.18 - 4.29), 0.014

1.05 (0.75 - 1.46), 0.76

Mechanical ventilation

1.06 (0.59 - 1.90), 0.84

1.16 (0.48 - 2.79), 0.72

1.35 (0.92 - 1.99), 0.12

Pressor use

1.28 (0.72 - 2.29), 0.39

0.58 (0.21 - 1.64), 0.31

0.82 (0.57 - 1.19), 0.31

In hospital mortality

1.03 (0.66 - 1.59), 0.88

0.34 (0.12 - 0.96), 0.04

1.05 (0.79 - 1.39), 0.07

Readmission

1.12 (0.78 - 1.58), 0.54

1.39 (0.81 - 2.39), 0.22

1.04 (0.83 - 1.31), 0.71