ABO Phenotype and Clinical Correlates of COVID-19 Severity in Hospitalized Patients

Figures & data

Table 1. Demographic and clinical characteristics that differ across ABO blood type groups.

Blood type (sample size)	A (143)	AB (18)	B (45)	O (267)	Main effect ^†	Pairwise post hoc comparisons (p-values)
Demographics	n (%)	n (%)	n (%)	n (%)	p-value	A-AB	A-B	A-O	AB-B	AB-O	B-O
Hispanic ethnicity	102 (71.3%)	9 (50%)	26 (57.8%)	206 (77.2%)	0.006	0.463	0.463	0.476	0.779	0.105	0.061
Age ^§ , mean (SD)	64.2 (16.5)	64.83 (20.3)	55.73 (18.1)	60.32 (16.0)	0.011	0.999	0.015	0.110	0.200	0.678	0.315
Comorbidities	n (%)	n (%)	n (%)	n (%)	p-value	A-AB	A-B	A-O	AB-B	AB-O	B-O
CKD or ESRD	37 (25.9%)	9 (50%)	7 (15.6%)	69 (25.8%)	0.047	0.255	0.581	>0.999	0.071	0.255	0.581
Initial lab values ^‡	Mean (SD)	Mean (SD)	Mean (SD)	Mean (SD)	p-value	A-AB	A-B	A-O	AB-B	AB-O	B-O
Peak creatinine ^¶‡ (Cr, 0.5–1.0 mg/dl)	2.06 (2.29)	3.8 (3.53)	1.4 (1.73)	2.28 (3.09)	0.018	0.062	0.513	0.872	0.012	0.115	0.205
Peak neutrophils ^#‡ (neutrophils %, 38–74%)	83.4 (9.8)	88.52 (4.71)	81.69 (8.9)	84.96 (9.13)	0.020	0.134	0.696	0.360	0.046	0.411	0.123
Mean lymphocytes ^#‡ (lymphocytes %, 16–48%)	14.35 (7.7)	11.06 (4.38)	17.61 (8.46)	14.94 (8.02)	0.019	0.364	0.074	0.886	0.019	0.200	0.154
Monocytes ^# (monocytes %, 4.9–12.5%)	6.97 (3.99)	5.29 (2.97)	6.03 (2.77)	6.02 (3.42)	0.038	0.248	0.406	0.048	0.881	0.841	>0.999
Peak D-dimer (<500 ng/ml) ^††‡	2394.68 (2755.2)	3342.95 (3034.84)	1491.12 (1994.32)	2687.8 (2799.17)	0.040	0.559	0.260	0.775	0.099	0.789	0.049

† Main effect p-values indicate overall comparison across all blood type groups. Only significant main effects have respective pairwise comparisons with p-values shown.

‡ Specified measures were not from initial labs and represent either peak or mean across entire hospitalization.

§ One patient missing data, n = 472 for age.

¶ Metabolic panel n = 464–465.

# Blood count n = 471–473.

†† Inflammatory markers n = 395–408.

CKD: Chronic kidney disease; ESRD: End-stage renal disease; SD: Standard deviation.

Figure 1. Odds ratio plots for primary outcomes by blood type.

Odds of ICU admission, intubation and death for blood types O, B and AB relative to blood type A. The odds of death was lower among blood type B relative to blood type A on univariate analysis.

ICU: Intensive care unit.

Table 2. Study outcomes by blood group.

Outcomes	A (n = 143)		AB (n = 18)		B (n = 45)		O (n = 267)		Main effect	p-value (A is reference)			Adj ^‡ p-value
	n (%)	OR ^† (95% CI)	n (%)	OR ^† (95% CI)	n (%)	OR ^† (95% CI)	n (%)	OR ^† (95% CI)	p-value ^†	AB	B	O
ICU	61 (42.7%)	Ref	9 (50%)	1.34 (0.5–3.6)	15 (33.3%)	0.67 (0.3–1.3)	122 (45.7%)	1.13 (0.8–1.7)	0.424				0.643
Intubation	47 (32.9%)	Ref	7 (38.9%)	1.3 (0.5–3.5)	10 (22.2%)	0.58 (0.3–1.2)	85 (31.8%)	0.95 (0.6–1.5)	0.477				0.590
Death	34 (23.8%)	Ref	7 (38.9%)	2.04 (0.7–5.6)	4 (8.9%)	0.31 (0.1–0.9)	55 (20.6%)	0.83 (0.5–1.4)	0.037	0.172	0.038	0.457	0.197
	Median ^§ (IQR)	HR ^¶ (95% CI)	Median ^§ (IQR)	HR ^¶ (95% CI)	Median ^§ (IQR)	HR ^¶ (95% CI)	Median ^§ (IQR)	HR ^¶ (95% CI)	LOS ^§ p-value	Surv ^¶ p-value	Adj ^# p-value
LOS^#	9 (5.0–17.0)	Ref	9 (5.3–15.3)	0.66 (0.4–1.2)	8 (4.0–17.0)	1.42 (1.0–2.0)	10 (6.0–21.0)	0.95 (0.8–1.2)	0.139	0.0695	0.1446

† OR and 95% CI calculated from independent, univariable logistic regression to identify effects of blood type on ICU admissions, intubation and death.

‡ Adjusted p-values are from tests of conditional associations of blood type on each outcome in a multivariable logistic regression model including Hispanic ethnicity, age and CKD.

§ Median LOS was compared using a Kruskal–Wallis test.

¶ HR and 95% CI’s result from a univariable Cox proportional hazards model with blood type as an independent predictor of survival to discharge, censoring on in-hospital death, with p-value indicated.

# The adjusted p-value is from a multivariable Cox proportional hazards model to test conditional associations of blood type accounting for Hispanic ethnicity, age and CKD.

CKD: Chronic kidney disease; HR: Hazard ratio; ICU: Intensive care unit; IQR: Interquartile range; LOS: Length of hospital stay; OR: Odds ratio.

Table 3. Exploratory multivariable analyses for COVID-19 severity outcomes among all patients.

ICU admission	OR (95% CI)	p-value
Hispanic	1.69 (1.06–2.71)	0.0274
Sex	2.13 (1.42–3.22)	0.0003
Diabetes	1.88 (1.25–2.86)	0.0028
DVT/thrombosis/pulmonary embolism	2.62 (1.54–4.52)	0.0004
Anemia	2.76 (1.83–4.19)	<0.00001
Intubation	OR (95% CI)	p-value
Hispanic	1.96 (1.15–3.42)	0.0145
Sex	2.09 (1.33–3.33)	0.0017
BMI	1.03 (1.01–1.06)	0.0162
DVT/thrombosis/pulmonary embolism	2.48 (1.46–4.24)	0.0008
COPD/emphysema	2.18 (1.19–3.98)	0.0112
Anemia	5.04 (3.16–8.19)	<0.00001
Death	OR (95% CI)	p-value
Age	1.04 (1.03–1.06)	<0.00001
Sex	2.75 (1.67–4.63)	0.0001
COPD	1.93 (1.07–3.47)	0.0276
Anemia	1.74 (1.07–2.85)	0.0271

COPD: Chronic obstructive pulmonary disease; DVT: Deep venous thrombosis; OR: Odds ratio.