Table 1 Demographic and epidemiological characteristics of severe COVID-19 patients in the southeast Iran

Age (year)

 Less/equal 50

254 (61.5)

62 (24.4)

1

 More than 50

159 (38.5)

83 (52.2)

3.38 (2.22,5.16)*

Sex

 Female

184 (44.5)

65 (35.3)

1

 Male

229 (55.5)

80 (34.9)

0.98 (0.66,1.48)^NS

Cigarette smoking

 No

397 (96.1)

138 (34.8)

1

 Yes

16 (3.9)

7 (43.8)

1.46 (0.53,4.00) ^NS

Substance abuse

 No

376 (91)

126 (33.5)

1

 Yes

37 (9)

19 (51.4)

2.09 (1.06,4.13)*

Travel to high-risk areas

 No

357 (86.4)

136 (38.1)

1

 Yes

56 (13.6)

9 (16.1)

0.31 (0.14,0.65)*

Go to the medical care center within 14 days before the onset of symptoms

 No

362 (87.6)

122 (33.7)

1

 Yes

51 (12.4)

23 (45.1)

1.62 (0.89,2.92) ^NS

Close contact with a respiratory patient within 14 days before the onset of symptoms

 No

365 (88.3)

127 (34.8)

1

 Yes

48 (11.7)

18 (37.5)

1.12 (0.60,2.10) ^NS

Close contact with a respiratory patient within 14 days before the onset of symptoms in medical centers

 No

389 (94.1)

133 (34.2)

1

 Yes

24 (5.9)

12 (50.0)

1.93 (0.84,4.40) ^NS

Close contact with a respiratory patient within 14 days before the onset of symptoms in the family

 No

375 (90.8)

130 (34.7)

1

 Yes

38 (9.2)

15 (39.5)

1.23 (0.62,2.44) ^NS

Close contact with a respiratory patient within 14 days before the onset of symptoms in the workplace

 No

402 (97.3)

142 (35.3)

1

 Yes

11 (2.7)

3 (27.3)

0.69 (0.18,2.63) ^NS

History of close contact with a COVID19 patient within 14 days before the onset of symptoms

 No

397 (96.1)

137 (34.5)

1

 Yes

16 (3.9)

8 (50.0)

1.90 (0.70,5.17) ^NS

Using Mask protection

 No

242 (58.6)

106 (43.8)

1

 Yes

171 (41.4)

39 (22.8)

0.38 (0.25,0.59) ^NS

How transferred to a medical center

 Personally

223 (54.4)

54 (24.2)

1

 By others

104 (25.3)

44 (42.3)

2.30 (1.40,3.77)*

 By ambulance

83 (20.3)

44 (53.0)

3.53 (2.08,5.99)*

Distance protection

 No

404 (97.8)

142 (35.1)

1

 Yes

9 (2.2)

3 (33.3)

0.92 (0.23,3.74) ^NS

The duration between symptom onset and hospital admission (day)

 More than 1

362 (87.6)

121 (33.4)

1

 Less/equal 1

51 (12.4)

24 (47.1)

1.77 (0.98,3.20) ^NS