The Charlson Comorbidity Index as an Independent Prognostic Factor in Older Colorectal Cancer Patients

High-age patients have higher rates of comorbidity that are associated with a poor prognosis. It is important to correctly evaluate their preoperative status to avoid mortality. The aim of this study was to clarify whether the Charlson comorbidity index (CCI) was useful for predicting postoperative outcomes. This retrospective study collected data from 250 consecutive patients over 75 years of age. The CCI takes into account 19 comorbid conditions. Inflammation-based scores, including the Glasgow prognostic score (GPS) and the platelet to lymphocyte ratio (PLR), are other preoperative scoring systems. The relationships among these scores and postoperative outcomes were evaluated. The patients were classified according to their vital status (dead, n = 30 or alive, n = 220). Comorbidities, the presence of double cancer, and lymph node metastases were significantly different between the groups (p < 0.01, p = 0.01, and p < 0.01). In regard to the scoring systems, the CCI, GPS, and PLR were significantly different (p = 0.02, p = 0.03, and p = 0.05). Multivariate analysis identified CCI ≥ 2 (hazard ratio (HR) = 5.24, 95 % confidence interval (CI) = 1.30–12.1, p = 0.01) as a significant determinant of postoperative outcome (p < 0.01). The overall survival tended to be lower in patients with high CCI scores group (p = 0.03). The CCI was useful to predict postoperative outcomes in high-age colorectal cancer patients.