Relationship between preoperative modified frailty index, immune-inflammation index, and outcomes of colorectal cancer surgery in older patients

Table 1 Univariate analysis of complications affecting older patients with colorectal cancer 30 days after surgery, n (%)/mean ± SD

Variable	Complication group (n = 31)	Non-complication group (n = 216)	t/χ2	P value
Age (years)	73.87 ± 6.34	71.17 ± 6.46	2.182	0.030
Sex			1.767	0.184
Male	21 (7.74)	119 (55.09)
Female	10 (32.26)	97 (44.91)
BMI (kg/m2)	23.12 ± 1.48	22.60 ± 1.30	2.074	0.039
Smoking history			8.786	0.003
Yes	18 (58.06)	67 (31.02)
No	13 (41.94)	149 (68.98)
Drinking history			4.461	0.035
Yes	17 (54.84)	76 (35.19)
No	14 (46.15)	140 (64.81)
Operation time (minutes)	182.42 ± 22.32	162.78 ± 20.59	4.915	< 0.001
Preoperative bleeding (mL)	125.32 ± 26.39	123.17 ± 27.42	0.411	0.681
Tumor site			0.883	0.347
Rectum	14 (45.16)	117 (54.17)
Colon	17 (54.84)	99 (45.83)
Tumor size			12.114	0.001
< 5 cm	9 (29.03)	134 (62.04)
≥ 5 cm	22 (70.97)	82 (37.96)
Degree of tumor differentiation			7.960	0.019
High	15 (48.39)	101 (46.76)
Moderately	7 (22.58)	89 (41.20)
Poorly	9 (29.03)	26 (12.04)
TNM stage			1.372	0.504
I	9 (29.03)	71 (32.87)
II	14 (45.16)	108 (50.00)
III	8 (25.81)	37 (17.13)
Pre-operative mFI (points)	6.19 ± 1.19	4.12 ± 0.86	9.338	< 0.001
Pre-operative SII (× 109/L)	1091.43 ± 584.13	760.80 ± 370.50	3.064	0.004

mFI: Modified frailty index; SII: Systemic immune-inflammation index; TNM: Tumor-node-metastasis; BMI: Body mass index.