Table 2

Univariate association of baseline variables with the primary outcome*

Baseline variables	OR	P value
Age	0.99	<0.0001
Female	0.86	<0.0001
Race
White	Reference	Reference
Black	0.84	<0.0001
Hispanic	0.57	<0.0001
Asians	0.39	<0.0001
Native Americans	0.55	<0.0001
Others	0.69	<0.0001
Charleston Comorbidity Index	0.58	<0.0001
Hospital bed size	1.05	0.001
Hospital teaching status	1.21	<0.0001
Hospital location	1.31	<0.0001
Expected primary payer	1.50	<0.0001
Median household income (quartile)	1.11	<0.0001
Hospital region	0.89	<0.0001
Dyslipidemia	0.39	<0.0001
Old MI	0.37	<0.0001
Old PCI	0.36	<0.0001
Old CABG	0.28	<0.0001
Old pacemaker	0.26	<0.0001
Atrial fibrillation/flutter	0.35	<0.0001
COPD	0.39	<0.0001
Old stroke	0.41	<0.0001
Hypertension	0.71	<0.0001
Peripheral vessel disease	0.28	<0.0001
Hypothyroidism	0.59	<0.0001
DM types 1 and 2	0.37	<0.0001
Obesity	0.64	<0.0001
CHF	0.18	<0.0001
CKD	0.29	<0.0001
Liver disease	0.94	0.018
Electrolyte derangement	1.59	<0.0001
Maintenance hemodialysis	0.14	<0.0001
O₂ dependence	0.15	<0.0001
Smoking	1.15	<0.0001
Anemia	2.18	<0.0001
CAD	0.31	<0.0001
On anticoagulation	0.53	<0.0001

*IBD as the principal diagnosis for hospitalizations.
CABG, coronary artery bypass graft; CAD, coronary artery disease; CHF, chronic congestive heart failure; CKD, chronic kidney disease; COPD, chronic obstructive pulmonary disease; DM, diabetes mellitus; IBD, inflammatory bowel disease; MI, myocardial infarction; PCI, percutaneous coronary intervention.