The association between body mass index and postoperative complications, 30-day mortality and long-term survival in Dutch patients with colorectal cancer

Introduction: This retrospective study aims to examine the association between body mass index (BMI) and serious postoperative complications, 30-day mortality and overall survival in colorectal cancer (CRC) patients. Materials and methods: All CRC patients diagnosed between 2008 and 2013 in the south-eastern part of the Netherlands were included. Patients were categorized into four BMI groups: underweight (<18.5), normal weight (18.5 >= BMI<25), overweight (25 >= BMI<30), and obese (>= 30). Results: A total of 7371 CRC patients were included (underweight 133 (1.8%); normal weight 2054 (41.4%); overweight 2955 (40.1%); obesity 1229 (16.7%)). Underweight patients were more likely to have postoperative complications (18.8% vs. 11.7%, adjusted OR 1.95, 95% CI 1.08-3.49) and had a worse 30-day mortality (9.8% vs. 3.3%, adjusted OR 4.37, 95% CI 2.03-9.42) compared to normal weight patients. After stratification for stage (stage I-Ill and stage IV), underweight was associated with a worse overall survival in both groups compared to normal weight (stage I-III: HR 2.06, 95%CI 1.51-2.80; stage IV: HR 1.65, 95% CI 1.11-2.45). Overweight was associated with an improved overall survival compared to normal weight in both stage groups. Only in stage IV patients obesity was associated with a significant better overall survival compared to stage IV normal weight patients. Conclusion: Underweight CRC patients were more likely to have postoperative complications and a worse 30-day mortality compared to patients in other EMI categories. The underweight population also has a worse long-term survival while overweight CRC patients and obese stage IV CRC patients were associated with an improved survival compared to normal weight patients. (C) 2018 Elsevier Ltd, BASO similar to The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.