Table 4. Sensitivity analysis.

	Sensitivity analysis I‡		Sensitivity analysis II§		Sensitivity analysis III||
	Boundary	HR (95% CI)	Boundary	HR (95% CI)	Boundary	HR (95% CI)
ALT (IU/L)
Low	≤11	1.43 (1.01–2.02)*	≤9	1.20 (0.79–1.84)	≤13	1.69 (1.23–2.34)†
Middle		1 (reference)		1 (reference)		1 (reference)
High	>35	0.88 (0.54–1.44)	>23	0.68 (0.47–0.99)*	>30	0.95 (0.61–1.48)
AST (IU/L)
Low	≤16	1.32 (0.89–1.95)	≤17	1.39 (0.90–2.14)	≤17	1.35 (0.93–1.96)
Middle		1 (reference)		1 (reference)		1 (reference)
High	>34	1.42 (0.96–2.09)	>22	1.27 (0.86–1.86)	>30	1.38 (0.97–1.97)
De Ritis ratio
Low	≤0.78	0.57 (0.30–1.10)	≤1.19	0.63 (0.44–0.91)*	≤0.85	0.58 (0.34–0.99)*
Middle		1 (reference)		1 (reference)		1 (reference)
High	>1.75	1.67 (1.21–2.32)†	>2.06	1.54 (1.05–2.26)*	>1.62	1.59 (1.15–2.21)†

^*P<0.05, ^†P<0.01.

^‡Serum aminotransferase levels were categorized into ≤15th percentile, 15th–85th percentile, and >85th percentile.

^§Serum aminotransferase levels were categorized by “K-Adaptive Partitioning for survival data” method.

^{‡ §}Adjusted by sex, age, body mass index, estimated glomerular filtration rate, type of surgery, urgent surgery, ejection fraction, pulmonary hypertension, acute coronary syndrome, albumin, bilirubin, liver disease, statin, and alcohol.

^||Adjusted with EuroSCORE, MELD Xi, diabetes mellitus, hypertension, heart failure, coronary revascularization, atrial fibrillation, hematocrit, sodium, uric acid, diuretics, C-reactive protein, inotropes/vasopressors, dyslipidemia, alcohol, albumin, and liver disease.

SI conversion factors: To convert ALT and AST to μkat/L, multiply values by 0.0167.

ALT: alanine aminotransferase; AST: aspartate aminotransferase; HR: hazard ratio; CI: confidence interval.