. 2009 Apr 30;30(13):1574–1583. doi: 10.1093/eurheartj/ehp134

Table 2.

Predictors of hospital length of stay and mortality in the test cohort

	All-cause mortality				Hospital length of stay
	Univariate Cox		Multivariate Cox		Univariate Cox		Multivariate Cox
Demographics and past medical history	HR (95% CI)	P-value	HR (95% CI)	P-value	HR (95% CI)	P-value	HR (95% CI)	P-value
Age (decade)	1.87 (1.31–2.68)	<0.001	1.83 (1.25–2.68)	0.002	1.19 (1.11–1.28)	<0.001	1.17 (1.08–1.27)	<0.001
Gender (female)	0.55 (0.19–1.57)	0.267	0.39 (0.13–1.17)	0.095	1.04 (0.84–1.29)	0.683	0.95 (0.76–1.19)	0.674
Race (Caucasian)	N/A	0.989	N/A	0.988	1.08 (0.81–1.45)	0.565	1.20 (0.88–1.64)	0.226
Diabetes (treated)	0.82 (0.37–1.83)	0.632			0.96 (0.80–1.16)	0.749
Pulmonary disease	3.76 (1.32–10.7)	0.013			1.21 (0.78–1.85)	0.382
Hypercholesterolemia	0.37 (0.18–0.75)	0.005			0.74 (0.60–0.92)	0.007
Previous MI	1.17 (0.56–2.47)	0.674			1.20 (0.99–1.46)	0.061
Hypertension	0.42 (0.21–0.84)	0.014	0.33 (0.16–0.67)	0.002	1.28 (1.05–1.55)	0.013	1.27 (1.04–1.56)	0.019
LV ejection fraction (5% increment)	0.85 (0.75–0.96)	0.015	0.86 (0.75–0.98)	0.024	0.94 (0.91–0.97)	0.002	0.96 (0.93–0.99)	0.034

Pre-operative laboratory results
Creatinine (mg/dL)	2.70 (0.11–65.6)	0.542			3.38 (1.49–7.63)	0.003
Haematocrit (%)	0.94 (0.87–1.02)	0.112	0.91 (0.84–0.99)	0.045	0.97 (0.95–0.99)	0.015

Pre-operative drugs
ACE-inhibitor	0.68 (0.34–1.39)	0.291			1.11 (0.94–1.32)	0.196
Antiarrhythmic	1.77 (0.42–7.42)	0.433			2.06 (1.23–3.46)	0.006	1.75 (1.01–3.05)	0.046
Digoxin	7.30 (2.82–18.9)	<0.001			2.35 (1.35–4.09)	0.002	2.15 (1.20–3.87)	0.01
β-Blocker	0.57 (0.27–1.20)	0.14			0.93 (0.75–1.16)	0.578
Ca²⁺ Channel inhibitor	0.83 (0.29–2.37)	0.729			1.30 (1.02–1.67)	0.034	1.37 (1.06–1.79)	0.016
Platelet-inhibitor (non-ASA)	0.30 (0.07–1.27)	0.102			1.42 (1.14–1.78)	0.002	1.58 (1.25–2.01)	<0.001
Diuretic	1.45 (0.67–3.12)	0.345			1.31 (1.07–1.62)	0.009
HMG Co-A reductase inhibitor	0.37 (0.18–0.74)	0.005			0.68 (0.54–0.85)	<0.001	0.59 (0.47–0.75)	<0.001

Intraoperative characteristics
Aortic cross-clamp duration (30 min increment)	0.74 (0.50–1.10)	0.15			1.12 (1.02–1.22)	0.009
CPB duration (30 min increment)	0.88 (0.65–1.19)	0.461			1.19 (1.11–1.28)	<0.001	1.19 (1.10–1.29)	<0.001
Euroscore (logistic, 10% increment)	1.76 (1.06–2.91)	0.027			1.75 (1.37–2.23)	<0.001

Post-operative ECG
Last ECG-MI^{3, 4}	0.61 (0.25–1.5)	0.288			0.84 (0.69–1.03)	0.1
Last ECG-MI⁴	0.48 (0.16–1.36)	0.17			0.87 (0.71–1.08)	0.223
Highest ECG-MI^{3, 4}	1.13 (0.57–2.24)	0.724			1.08 (0.91–1.29)	0.335
Highest ECG-MI⁴	1.21 (0.60–2.43)	0.587			1.12 (0.94–1.35)	0.189
Lowest ECG-MI^{3, 4}	0.31 (0.04–2.29)	0.254			0.86 (0.63–1.18)	0.374
Lowest ECG-MI⁴	N/A	0.984			0.90 (0.64–1.28)	0.589
Median ECG-MI^{3, 4}	0.37 (0.11–1.22)	0.105			0.83 (0.67–1.03)	0.108
Median ECG-MI⁴	0.49 (0.15–1.63)	0.251			0.90 (0.71–1.14)	0.411

Cardiac biomarkers
CKMB Preoperative (25 µg/L increment)	3.82 (0.03–412)	0.574			2.40 (0.51–11.2)	0.264
CKMB POD1 (25 µg/L increment)	1.17 (0.99–1.37)	0.056			1.12 (1.07–1.18)	<0.001
cTnI Preoperative (1 µg/L increment)	0.20 (0.00–23.7)	0.513			1.05 (0.77–1.44)	0.717
cTnI POD1 (10 µg/L increment)	1.35 (1.10–1.66)	0.003			1.21 (1.08–1.36)	<0.001

Variables shown in multivariable model columns are included in Cox proportional hazards analysis. Data are shown in respective increments to show better inter-variable distinction. HR, hazard ratio; CI, confidence interval; MI, myocardial infarction; LV, left ventricle; Ca²⁺, calcium; ASA, acetylsalicylic acid; HMG, 3-hydroxy-3-methyl-glutaryl-CoA reductase; CPB, cardiopulmonary bypass; ECG, electrocardiogram; CKMB creatinine kinase MB fraction; cTnI, cardiac troponin I; POD, post-operative day.