Risk Factors for Prolonged Length of Stay of Older Patients in an Academic Emergency Department: A Retrospective Cohort Study

Table 5

Multivariable analysis: independent risk factors for a prolonged LOS (LOS > 293 minutes) at the .

			95% CI
	Odds Ratio	Standard Error	Lower	Upper	p-value
Patient characteristics
Age, per year increase	1.0	0.0096	0.98	1.0	0.66
Female sex (ref = male)	1.1	0.13	0.85	1.4	0.56
Polypharmacy	1.1	0.14	0.84	1.4	0.56
Organizational factors
Presentation on weekend (ref = midweek)	0.75	0.11	0.57	1.0	0.051
Time of presentation (ref = morning)
Night (00.00 - 6.59)	0.66	0.18	0.39	1.1	0.13
Afternoon (12.00 - 17.59)	1.2	0.19	0.89	1.6	0.23
Evening (18.00 - 23.59)	0.85	0.15	0.59	1.2	0.37
Number of consultations, per 1 consultation increase	2.4	0.22	2.0	2.9	<0.001
Number of diagnostic interventions, per additional intervention	1.5	0.080	1.4	1.7	<0.001
Assigned urgency (ref = U0)
U1 - U2	4.8	1.9	2.2	10	<0.001
U3 - U4	6.3	2.5	2.9	14	<0.001
U5 or missing	2.9	1.3	1.2	6.8	0.016
Clinical factors
Presenting complaint (ref = trauma)
High energetic trauma	3.1	2.4	0.71	14	0.13
Resuscitation	9.8	18	0.27	356	0.21
Neurological	2.2	0.81	1.0	4.5	0.038
Internal medicine	2.6	0.77	1.4	4.6	0.002
Altered consciousness: collapse or confused	3.3	1.2	1.6	6.6	0.001
Sequelae of medical procedure	1.7	0.72	0.71	3.9	0.25
Other than the above	3.3	1.6	1.3	8.4	0.015
Treating specialty (ref = emergency physician)
Surgery	3.4	0.75	2.2	5.2	<0.001
Internal medicine	2.6	0.46	1.9	3.7	<0.001
Geriatrics	0.66	0.25	0.32	1.4	0.26
Pulmonology	2.2	0.54	1.4	3.6	<0.001
Neurology	1.5	0.34	0.98	2.3	0.064
Other than the above	1.0	0.30	0.57	1.8	0.96

Area under the receiver operating characteristic curve: 0.79; pseudo R2, 0.18.
LOS: length of stay
ED: emergency department