Age-adjusted Charlson comorbidity index and its association with body composition and overall survival in patients with colorectal cancer

To examine the relationship between the age-adjusted Charlson comorbidity index (A-CCI) with body composition and overall survival in patients newly diagnosed with colorectal cancer (CRC).

In this cohort study, patients (≥ 18 years old) with CRC were followed for 36 months. Computed tomography images of the third lumbar were analyzed to determine body composition, including skeletal muscle area (SMA), skeletal muscle index (SMI), skeletal muscle radiodensity (SMD), visceral adipose tissue (VAT), and subcutaneous adipose tissue (SAT). Phenotypes based on comorbidity burden assessed by A-CCI and body composition parameters were established.

A total of 436 participants were included, 50% male, with a mean age of 61 ± 13.2 years. Approximately half of the patients (50.4%) had no comorbidity, and the A-CCI median score was 4 (interquartile range: 3–6). A higher A-CCI score was a risk factor for 36-month mortality (HR = 3.59, 95% CI = 2.17–5.95). Low SMA and low SMD were associated with a higher A-CCI. All abnormal phenotypes (high A-CCI and low SMA; high A-CCI and low SMD; high A-CCI and high VAT) were independently associated with higher 36-month mortality hazard (_adjusted HR 5.12, 95% CI 2.73–9.57; _adjusted HR 4.58, 95% CI 2.37–8.85; and _adjusted HR 2.36, 95% CI 1.07–5.22, respectively).

The coexistence of comorbidity burden and abnormal body composition phenotypes, such as alterations in muscle or fat compartments, may pose an additional risk of mortality in patients newly diagnosed with CRC. Early assessment and management of these phenotypes could be crucial in optimizing outcomes in such patients.