Table 1 Baseline characteristics in the vaccinated and non-vaccinated population

Age in years^a

57.11 ± 15.13

57.54 ± 14.60

57.00 ± 15.28

Gender (male/female)

591/250

(70.27/29.73)

121/53

(69.54/30.46)

470/197

(70.46/29.54)

Diabetes mellitus

445(52.91)

70(40.23)

375(56.22)

Hypertension

443(52.68)

62(35.63)

381(57.12)

Chronic kidney disease

100(11.89)

10(5.75)

90(13.49)

Chronic liver disease

20(2.38)

5(2.87)

15(2.25)

Ischaemic heart disease

116(13.79)

18(10.34)

98(14.69)

Immunosuppressants

28(3.33)

2(1.15)

26(3.90)

Malignancy

16(1.90)

4(2.30)

12(1.80)

COPD

31(3.69)

4(2.30)

27(4.05)

Bronchial asthma

30(3.57)

5(2.87)

25(3.75)

Interstitial lung disease

7(0.83)

2(1.15)

5(0.75)

Retroviral disease

2(0.24)

0(0)

2(0.30)

Tuberculosis

17(2.02)

2(1.15)

15(2.25)

APACHE II score^b

28(23–33)

14(8–24.50)

29(26–34)

SOFA score^b

7(4–10)

6(4–8)

7(4–11)

Invasive mechanical ventilation

350(41.62)

46(26.44)

304(45.58)

Need for RRT

92(11.65)

8(6.50)

84(12.59)

ABG pH^a

7.34 ± 0.13

7.38 ± 0.11

7.33 ± 0.13

Steroid usage

719(85.49)

123(70.69)

596(89.36)

PaO2/FiO2 ratio^b

110

(78.35–182.5)

113.33

(82.27–175)

109.31

(77.79–187.26)

Duration of mechanical ventilation^b (In days)

7(3–11)

7.5(4.5–13)

6(3–11)

Length of ICU stay^b (In days)

7(4–13)

8(4–14)

7(4–13)