Table 3.

Cox regression analysis of the demographic and clinical factors associated with SARS-CoV-2 infection mortality.

Characteristic	HR	95 % CI	P	aHR	95 % CI	P
Gender
Female	1			1
Male	2.02	0.98−4.16	0.058	1.42	0.62−3.28	0.409
Age  Per 10 years more	1.81	1.44−2.28	<0.0001	2.08	1.48−2.92	<0.0001
Age unadjusted Charlson comorbidity index  Per one point more	1.32	1.12−1.57	0.001	1.07	0.83−1.37	0.605
Obesity¥
No	1			1
Yes	2.01	1.07−3.81	0.031	3.04	1.42−6.49	0.004
Being treated with at least one anti-hypertensive agent
No	1			1
Yes	2.78	1.56−4.94	<0.001	1.41	0.73−2.74	0.309
Disease severity†
Mild	1			1
Moderate	2.82	0.66−12.10	0.163	1.30	0.29−5.77	0.727
Severe	4.43	1.04−18.97	0.045	1.50	0.32−7.04	0.605
Critical	35.35	7.29−171.43	<0.0001	8.26	1.41−48.29	0.019
Presence of anemia*
No	1			1
Yes	2.43	1.33−4.43	0.004	1.31	0.67−2.59	0.429
Lymphocyte count  Per 100 cells/μL more	0.91	0.00−0.97	0.008	0.98	0.91−1.06	0.664
D-dimer
≤1000 μg/L	1			1
>1000 μg/L	2.70	1.45−5.02	0.002	1.13	0.57−2.23	0.725
C-reactive protein  Per 50 mg/L more	1.26	1.15−1.38	<0.0001	1.17	1.02−1.35	0.028
Creatinine,  Per 0.5 mg/dL more	1.08	1.01−1.15	0.030	1.0	0.92−1.1	0.528
Creatine kinase
≤185 U/L	1			1
>185 U/L	3.26	1.84−5.75	<0.001	2.58	1.37−4.87	0.003

HR = hazard ratio; aHR = adjusted hazard ratio; CI = confidence interval.

^¥Obesity defined as body mass index ≥30 points [10].

^†Disease severity classification proposed by Wu et al. [12]: mild (mild clinical symptoms, no imaging signs of pneumonia); moderate (fever, cough, dyspnea or other symptoms, imaging signs of pneumonia); severe (any of: respiratory distress with respiratory rate (RR) of ≥30 breaths per minute; resting oxygen saturation in air ≤93 %; or PaO₂ / FiO₂ ≤300 mmHg); and critical (any of: respiratory failure requiring mechanical ventilation; shock; or any other organ failure needing intensive care).

^*Anemia defined as hemoglobin <12.5 g/dL for females, and <14 g/dL for males.