Table 3.

Subgroup analysis of the associations between all-cause mortality and length of stay.

	Group 1	Group 2		Group 3		Group 4
		HR(95%CI)	p-value	HR(95%CI)	p-value	HR(95%CI)	p-value	p-interaction
Age								0.202
<65 (n = 493)	Reference	0.13(0.02,1.04)	0.055	1.32(0.40,4.37)	0.652	0.78(0.30,2.07)	0.622
≥65 (n = 548)	Reference	1.83(0.73,4.58)	0.198	3.97(1.62,9.72)	0.003*	3.26(1.53,6.93)	0.002*
BMI								0.223
<25 (n = 264)	Reference	0.95(0.65,3.61)	0.941	4.71(1.67,13.30)	0.003*	2.19(0.90,5.31)	0.080
25–29.9 (n = 358)	Reference	0.52(0.12,2.16)	0.367	1.12(0.36,3.56)	0.391	1.12(0.36,3.55)	0.839
≥30 (n = 418)	Reference	1.12(0.21,5.93)	0.895	2.48(0.45,13.67)	0.296	2.54(0.72,8.92)	0.147
Percutaneous coronary intervention								0.115
No (n = 843)	Reference	0.56(0.23,1.37)	0.203	2.94(1.40,6.16)	0.004*	1.60(0.88,2.90)	0.121
Yes (n = 198)	Reference	7.98(0.57,112.61)	0.124	2.37(0.16,34.89)	0.531	8.90(0.49,162.03)	0.149
Myocardial infarct								0.199
No (n = 495)	Reference	0.29(0.06,1.32)	0.110	2.24(0.70,7.15)	0.175	1.64(0.72,3.72)	0.242
Yes (n = 546)	Reference	1.39(0.44,4.36)	0.570	3.38(1.15,9.93)	0.026	2.42(0.91,6.40)	0.076*
Congestive heart failure								0.399
No (n = 443)	Reference	1.01(0.28,3.72)	0.985	2.63(0.85,8.14)	0.094	1.70(0.61,4.72)	0.312
Yes (n = 598)	Reference	0.89(0.32,2.43)	0.817	3.28(1.34,8.02)	0.009*	2.11(1.02,4.34)	0.043*
APS-III								0.202
≤ 59 (n = 788)	Reference	2.06(0.41,10.33)	0.378	9.62(2.35,39.49)	0.002*	3.61(0.99,13.16)	0.051
>59 (n = 253)	Reference	0.64(0.25,1.61)	0.344	1.62(0.71,3.67)	0.252	1.46(0.75,2.88)	0.269
Charlson comorbidity index								0.401
≤ 3 (n = 668)	Reference	1.20(0.46,3.14)	0.710	3.14(1.28,7.69)	0.013*	2.00(0.89,4.51)	0.094
>3 (n = 373)	Reference	0.54(0.14,2.14)	0.384	2.61(0.85,8.04)	0.094	1.93(0.83,4.49)	0.128

Confounders adjustment were performed as in Model 2 (Table 2). Cox proportional hazards regression models were used to calculate hazard ratios (HRs) with 95%.

^*p < 0.05.