The impact of obesity on postoperative outcomes in colorectal cancer patients: a retrospective database study

Obesity is an independent risk factor for worse outcomes in various surgical settings. Whether obesity is a prognostic factor for postoperative morbidity and mortality of colorectal cancer (CRC) is inconclusive. This study aimed to determine the impact of obesity on short-term postoperative outcomes in CRC patients undergoing laparoscopic surgery.

Data of a total of 23,898 CRC patients aged ≥ 20 years and undergoing laparoscopic resection were extracted from the US National Inpatient Sample (NIS) database and analyzed. The study endpoints were in-hospital mortality, any postoperative complications, infection/sepsis, acute kidney injury (AKI), deep vein thrombosis (DVT)/pulmonary embolisms (PE), and extended hospital stay. Univariate and multivariate logistic regression analyses were performed to examine the associations between patients' obesity status (morbid obese: BMI >  = 40 kg/m²; obese: BMI 30-39.9 kg/m²) and the study outcomes.

In 23,898 CRC patients undergoing laparoscopic resection, the prevalence of obesity prevalence was 11.8%. After adjustment, the results revealed that morbid obesity was significantly associated with increased risk for in-hospital mortality (aOR = 2.06, 95%CI: 1.11-3.83), AKI (aOR = 1.78, 95%CI = 1.34-2.36), DVT/PE (aOR = 2.88, 95%CI = 1.70-4.88), and extended LOS (aOR = 1.21, 95%CI = 1.02-1.43), while non-morbid obesity was significantly associated with more DVT/PE (aOR = 2.12, 95%CI = 1.32-3.41) as compared with non-obesity.

In patients with CRC undergoing laparoscopic surgery, morbid obesity is strongly associated with worse postoperative outcomes, including increased in-hospital mortality, postoperative AKI and DVT/PE, and extended LOS. The findings of the present study highlight the importance of obesity status in risk stratification for laparoscopic CRC surgery.