Table 4.

Bivariate Cox regression of factors associated with disease progression from onset to severe disease or to death.

Patient characteristics and findings	Severe		Death
	HR (95% CI)	P-value	HR (95% CI)	P-value
Clinical characteristics
Age (≥65 vs. <65), y	2.26 (1.23–4.05)	0.006	2.06 (0.69–6.17)	0.195
Comorbidities
Cardiovascular and cerebrovascular diseases (yes vs. no)	2.54 (1.41–4.58)	0.002	2.79 (0.80–9.71)	0.106
Any (yes vs. no)	4.53 (1.78–11.55)	0.002	7.81 (1.02–59.86)	0.048
Laboratory findings
White blood cells, × 109/mL	1.13 (1.05–1.22)	0.001	1.25 (1.10–1.42)	0.001
Neurtrophils, × 109/mL	1.15 (1.07–1.23)	<0.001	1.28 (1.13–1.46)	<0.001
Lymphocytes, × 109/mL	0.16 (0.07–0.39)	<0.001	0.12 (0.03–0.35)	<0.001
Platelets, × 109/mL	0.89 (0.86–0.92)	<0.001	0.88 (0.85–0.91)	<0.001
LDH, U/L	1.14 (1.12–1.15)	<0.001	1.11 (1.10–1.12)	<0.001
APTT, sec	1.05 (1.01–1.09)	0.027	1.04 (0.95–1.14)	0.35
D-dimer, μg/mL	1.02 (1.01–1.03)	<0.001	1.02 (0.99–1.04)	0.155
CD3, /μL	0.87 (0.83–0.91)	<0.001	0.85 (0.81–0.89)	<0.001
CD4, /μL	0.83 (0.79–0.89)	<0.001	0.82 (0.78–0.88)	<0.001
CD19, /μL	0.86 (0.82–0.90)	0.061	0.83 (0.79–0.87)	0.035
C3, g/L	0.39 (0.073–2.05)	0.264	0.26 (0.03–1.37)	<0.001
Interleukin-6, pg/mL	1.02 (1.01–1.03)	0.033	NA
Interleukin-10, pg/mL	1.04 (1.01–1.07)	0.013	NA

LDH, lactate dehydrogenase; APTT, activated partial thromboplastin time; FDP, fibrinogen degradation products; NA, not available.