Table 1 Patient characteristics

Age, y

57 [52–70]

64 [55–71.5]

0.016

Sex, male (%)

87 (75.7)

103 (77.4)

0.74

BMI, kg/m²

25.8 ± 4.6

26.1 ± 5.1

0.67

Smoking history, past or current (%)

76 (66.1)

86 (65.3)

0.81

Past medical history, number (%)

 Asthma

10 (8.7)

9 (6.8)

0.57

 COPD

4 (3.5)

28 (13.5)

0.004

 Interstitial Pneumonia

0 (0)

3 (2.3)

0.52

 Malignancy

9 (7.8)

10 (7.5)

0.93

 HIV infection, AIDS

0 (0)

1 (0.8)

0.26

 Diabetes mellitus

23 (20.0)

43 (32.3)

0.03

 Chronic kidney disease

14 (12.2)

9 (6.8)

0.14

 Hemodialysis

1 (0.9)

1 (0.8)

0.91

 Cardiovascular disease

13 (11.3)

22 (16.5)

0.23

 Hypertension

60 (52.2)

65 (48.9)

0.60

 Chronic liver disease

7 (6.1)

12 (9.0)

0.38

 Cerebrovascular disease

8 (7.0)

12 (9.0)

0.55

Vital signs on admission

 Mean arterial pressure

101.2 ± 14.0

99.8 ± 13.0

0.44

 Heart rate

89 ± 17

90 ± 18

0.63

 Respiratory rate

24 ± 6

27 ± 7

0.03

 Consciousness disorder (GCS score < 15), (%)

8 (7.0)

17 (12.9)

0.11

Laboratory test results

 White blood cell count, × 10³/µL

7.4 [5.2–10.4]

6.5 [4.65–9.4]

0.08

 Lymphocyte count, /µL

608 [426–840]

487 [350–730]

0.01

 Hct level, %

41.1 ± 4.2

40.3 ± 5.3

0.63

 Serum albumin level, g/dL

3.0 ± 0.4

2.9 ± 0.4

0.39

 Lactate dehydrogenase level, IU/L

423 [345–548]

521 [441–662]

 < 0.0001

 Na level, mEq/L

135.8 ± 4.3

135.6 ± 4.4

0.90

 K level, mEq/L

4.08 ± 0.56

4.08 ± 0.56

0.73

 Creatinine level, mg/dL

0.75 [0.63–0.98]

0.83 [0.67–1.05]

0.07

 C-reactive protein level, mg/dL

8.24 [4.68–12.78]

9.19 [5.045–12.495]

0.73