Chemotherapy as a protective factor against cardiocerebrovascular disease mortality in colorectal cancer patients based on SEER database

The impact of chemotherapy on cardiocerebrovascular disease (CCVD) outcomes in patients with colorectal cancer (CRC) remains insufficiently explored. This research aimed to clarify the association between chemotherapy and CCVD-related mortality in middle-aged and elderly CRC patients. CRC patients aged ≥ 50 years at diagnosis were identified from the Surveillance, Epidemiology, and End Results (SEER) database for the period 2010–2015. The primary outcome was CCVD-related mortality. Survival analyses included Kaplan-Meier (KM) curves to characterize CCVD-related survival patterns and multivariate competing risks regression analysis to evaluate the independent association between chemotherapy and CCVD-related mortality. Subgroup analyses and Fine-Gray competing risks models were additionally performed to enhance the robustness of study findings. A total of 136 095 CRC patients were included. KM analysis showed a significantly lower cumulative risk of CCVD-related mortality in chemotherapy treatment group than in non-chemotherapy treatment group. After adjusting for age, race, gender, primary tumor site, and tumor stage, multivariate competing risks regression analysis confirmed that chemotherapy was an independent protective factor against CCVD-related mortality (sHR = 0.75, 95% CI 0.71–0.79, P < 0.001). Subgroup analyses and Fine-Gray competing risks models further validated the robustness of chemotherapy’s beneficial effect on CCVD outcomes. Chemotherapy may serve as an independent protective factor against CCVD-related mortality in CRC patients. These findings can help alleviate concerns regarding chemotherapy-associated CCVD risk in CRC management and provide novel insights for clinical decision-making and future research.