Table 3.

Proportional hazard regression results from intubation to 28-day in-hospital mortality

	Unadjusted* HR (95% CI)	P Value	Adjusted HR (95% CI)	P Value
Overcrowded ICU	1.43 (1.27–1.62)	<0.001	1.28 (1.12–1.45)	<0.001
Expanded ICU	1.21 (1.08–1.35)	0.001	1.07 (0.95–1.20)	0.28
Age (yr)
<65	1 [Reference]		1 [Reference]
⩾65–<74	1.35 (1.18–1.54)	<0.001	1.28 (1.11–1.47)	<0.001
⩾75–<84	1.52 (1.30–1.76)	<0.001	1.33 (1.13–1.56)	<0.001
⩾85	2.61 (2.03–3.37)	<0.001	2.20 (1.68–2.89)	<0.001
Female	0.90 (0.80–1.02)	0.11	0.87 (0.77–0.99)	0.04
BMI
<30	1 [Reference]		1 [Reference]
⩾30 (obesity)	0.88 (0.78–1.00)	0.03	0.98 (0.86–1.11)	0.73
Missing data	2.36 (1.95–2.87)	<0.001	2.50 (2.05–3.05)	<0.001
Hypertension	1.18 (1.05–1.33)	0.005	1.08 (0.95–1.22)	0.26
Diabetes	1.13 (1.01–1.27)	0.04	1.11 (0.98–1.25)	0.09
Chronic heart disease	1.46 (1.25–1.71)	<0.001	1.28 (1.09–1.51)	<0.001
Chronic lung disease	1.33 (1.01–1.74)	0.04	1.29 (0.97–1.70)	0.08
Time from admission until intubation (d)
<5	1 [Reference]		1 [Reference]
⩾5–<8	0.84 (0.69–1.03)	0.09	0.88 (0.72–1.07)	0.19
⩾8–<14	0.94 (0.79–1.13)	0.53	1.03 (0.86–1.24)	0.71
⩾14	1.17 (0.98–1.40)	0.08	1.26 (1.05–1.52)	0.01
Missing data	1.79 (1.46–2.21)	<0.001	1.79 (1.45–2.21)	<0.001
SAPS II, score points
<50	1 [Reference]		1 [Reference]
⩾50–<60	1.24 (1.03–1.48)	0.02	1.17 (0.97–1.41)	0.10
⩾60–<70	1.17 (0.97–1.41)	0.09	1.21 (1.01–1.46)	0.04
⩾70	1.52 (1.27–1.81)	<0.001	1.47 (1.22–1.75)	<0.001
Missing data	1.83 (1.46–2.29)	<0.001	1.65 (1.32–2.07)	<0.001

Definition of abbreviations: BMI = body mass index; CI = confidence interval; HR = hazard ratio; ICU = intensive care unit; SAPS II = Simplified Acute Physiology Score II.

^*Unadjusted model considers one variable of the model at a time.