Role of body mass index in colon cancer patients in Taiwan

Table 4 Results of multivariate analysis of colon cancer survival stratified according to body mass index category

	Underweight	Normal weight	Overweight	Obese
All patients (n = 2138)
Overall survival
HR (95% CI)1	1.58 (1.23-2.05)	Reference	0.83 (0.68-1.01)	0.94 (0.74-1.18)
P value2	< 0.001		0.060	0.578
Disease-free survival
HR (95% CI)1	1.49 (1.16-1.93)	Reference	0.86 (0.71-1.04)	1.00 (0.79-1.25)
P value2	0.002		0.123	0.972
Cancer-specific survival
HR (95% CI)1
P value2	1.33 (0.94-1.87)	Reference	0.96 (0.76-1.22)	1.06 (0.80-1.41)
	0.107		0.751	0.677
Males (n = 1109)
Overall survival
HR (95% CI)	1.55 (1.03-2.35)	Reference	0.77 (0.58-1.01)	0.91 (0.66-1.25)
P value2	0.036		0.056	0.565
Disease-free survival
HR (95% CI)1	1.60 (1.04-2.44)	Reference	0.84 (0.65-1.09)	1.01 (0.75-1.37)
P value2	0.031		0.192	0.937
Cancer-specific survival
HR (95% CI)1
P value2	1.46 (0.84-2.52)	Reference	0.96 (0.69-1.32)	1.21 (0.83-1.77)
	0.179		0.789	0.328
Females (n = 1029)
Overall survival
HR (95% CI)1	1.55 (1.11-2.16)	Reference	0.95 (0.71-1.27)	0.99 (0.69-1.41)
P value2	0.011		0.724	0.945
Disease-free survival
HR (95% CI)1	1.41 (1.01-1.97)	Reference	0.91 (0.68-1.22)	1.01 (0.71-1.43)
P value2	0.042		0.544	0.957
Cancer-specific survival
HR (95% CI)1
P value2	1.16 (0.75-1.82)	Reference	0.96 (0.69-1.36)	0.93 (0.60-1.43)
	0.508		0.839	0.727

¹HR was calculated using the Cox regression model; the variables in the multivariate analysis included TNM stage, age, gender (when analyzing all patients), comorbidities, CEA, hemoglobin, albumin, operative timing, postoperative morbidity, tumor location, histologic type, and histologic grade;

²Each category compared to normal-weight patients. HR: Hazard ratio; CI: Confidence interval; BMI: Body mass index; TNM: Tumor, nodes, metastasis; CEA: Carcinoembryonic antigen.