The association between body mass index and postoperative complications in patients with colorectal cancer

Abstract

Objective To investigate the association between body mass index and postoperative complications in patients with colorectal cancer. Methods 120 patients with colorectal cancer were prospectively studied.According to the body mass index, all patients were assigned to study group(BMI<18.5kg/m2) or control group(BMI≥18.5kg/m2), 60 cases in each group.All patients received elective colorectal cancer resection.The operation situation, postoperative complications, postoperative recovery and postoperative stress reaction of the two groups were observed. Results There were no significant differences in the operation time, the number of lymph node dissection and the amount of bleeding between the two groups during the operation(all P>0.05). Compared with the control group, the total infection rate of the study group was significantly higher(11.67% vs.1.67%, χ2=4.324, P=0.038); the incidence of postoperative complications was significantly increased(25.00% vs.5.00%, χ2=7.908, P=0.005). There were no significant differences in other complications such as wound infection, anastomotic leakage, anastomotic obstruction, adverse cardiovascular events and stress ulcer(all P>0.05). Compared with the control group, the postoperative anal exhaust time of the study group was significantly prolonged[(51.48±9.47)h vs.(43.73±8.63)h, t=5.382, P=0.000]; and the length of hospital duration was significantly prolonged[(20.35±3.21) d vs.(16.28±3.48)d, t=6.462, P=0.000]. There were no significant differences in recurrence rate, mortality rate and progression free survival between the two groups after 1 year (all P>0.05). There were no significant differences in preoperative IL-6 and CRP levels between the two groups(all P>0.05). Compared with the control group, the IL-6 level of the study group at 7-day after operation was significantly higher[(165.56±45.39) ng/L vs.(122.58±29.58)ng/L, t=6.459, P=0.000]; CRP level was significantly higher[(23.49±8.48) mg/L vs.(15.37±6.53)mg/L, t=4.285, P=0.002]. Conclusion Body mass index less than 18.5 kg/m2 is a risk factor for postoperative infection and complications in patients with colorectal cancer, and is associated with increased stress response and prolonged hospital stay. Key words: Body mass index; Colorectal cancer; Emaciation; Postoperative complications