Medical resource utilization among patients with ventilator-associated pneumonia: pooled analysis of randomized studies of doripenem versus comparators

Table 3 Cox proportional hazards regression for medical resource utilization

Parameter	Hazard ratio^a	95% Confidence interval	P value
Duration of mechanical ventilation
Unadjusted results
Treatment (doripenem)	1.29	1.08-1.53	0.005
Adjusted results
Treatment (doripenem)	1.28	1.07-1.52	0.006
Baseline MRSA (presence)	0.72	0.50-1.04	0.079
Baseline Pseudomonas aeruginosa (presence)	0.79	0.60-1.04	0.087
Baseline APACHE II score^b (≤20 versus >20)	0.77	0.61-0.95	0.017
ICU LOS
Unadjusted results
Treatment (doripenem)	1.16	0.98-1.37	0.079
Adjusted results
Treatment (doripenem)	1.14	0.97-1.35	0.122
Baseline P. aeruginosa (presence)	0.73	0.56-0.95	0.018
Region (North America)	1.22	1.04-1.45	0.018
Baseline APACHE II score	0.97	0.96-0.99	0.003
Total hospital LOS
Unadjusted results
Treatment (doripenem)	1.32	1.09-1.58	0.004
Adjusted results
Treatment (doripenem)	1.31	1.09-1.58	0.004
VAP onset (early)	1.30	1.08-1.57	0.005
Baseline P. aeruginosa (presence)	0.83	0.62-1.11	0.212
Region (North America)	1.51	1.25-1.82	<0.001

^a A hazard ratio significantly greater than 1 indicated that discharge was more likely to occur.
^b APACHE II score was dichotomous (not continuous as in previous models) to satisfy the proportional hazards assumption.
APACHE II, Acute Physiology and Chronic Health Evaluation II; LOS, length of stay; MRSA, methicillin-resistant Staphylococcus aureus; VAP, ventilator-associated pneumonia.

ISSN: 1364-8535