Table IV.

Cox proportional hazards model of survival over the first 5 years postoperatively

Covariate	HR (95% CI)	P
Postoperative complication
No stroke or MI	Referent
MI	2.8 (1.8–4.3)	<.0001
Stroke	2.7 (1.7–4.3)	<.0001
Age, years
<60	Referent
60–69	1.1 (.86–1.4)	.44
70–79	2.1 (1.6–2.6)	<.0001
>80	4.5 (3.5–5.8)	<.0001
Smoking status, never	0.65 (.54–.77)	<.0001
COPD
None/not treated	Referent
Medications	1.5 (1.3–1.8)	<.0001
Home oxygen	3.3 (2.5–4.5)	<.0001
CAD
None	Referent
History of MI or stable angina	1.2 (.99–1.4)	.06
Unstable angina or MI ≤6 months	.97 (.58–1.6)	.89
Previous coronary revascularization	0.99 (.85–1.2)	.87
Stress testing
Not performed	1.0 (.88–1.2)	.72
Normal	Referent
Ischemia/MI/both	1.2 (.96–1.5)	.12
Congestive heart failure	1.7 (1.4–2.1)	<.0001
Hypertension	.89 (.73–1.1)	.25
Diabetes mellitus	1.4 (1.2–1.6)	<.0001
Renal function
Creatinine ≤1.8 mg/dL	Referent
Creatinine >1.8 mg/dL	1.6 (1.3–1.9)	<.0001
Dialysis-dependent	5.3 (3.5–7.9)	<.0001
Contralateral ICA stenosis
<50%	Referent
50%–69%	1.1 (.96–1.3)	.15
70%–80%	1.3 (1.1–1.6)	.008
>80%	1.6 (1.3–2.1)	<.0001
Occluded	1.6 (1.3–2.1)	<.0001
Unknown	1.4 (1.0–2.0)	.04
Preoperative antiplatelet use	1.0 (.83–1.2)	.95
Preoperative statin use	.80 (.70–.92)	.002
General anesthesia	.77 (.66–.91)	.002

CAD, Coronary artery disease; CI, confidence interval; COPD, chronic obstructive pulmonary disease; HR, hazard ratio; ICA, internal carotid artery; MI, myocardial infarction.