Impact of Cardiovascular Comorbidities on the Effectiveness and Safety of Bevacizumab in Older Patients with Metastatic Colorectal Cancer.

Background: Cardiovascular comorbidities are not contraindications of bevacizumab for metastatic colorectal cancer.

Objective: We aimed to evaluate the impact of cardiovascular comorbidities before bevacizumab treatment on overall survival and cardiovascular safety in older patients with metastatic colorectal cancer.

Methods: A 2009-2015 cohort of patients with metastatic colorectal cancer aged ≥ 65 years administered first-line bevacizumab was extracted from the French healthcare reimbursement claims database. Baseline heart failure, hypertension, and venous/arterial thromboembolic events were identified. The 36-month overall survival rate was evaluated using the Kaplan-Meier method, and the impact of cardiovascular comorbidities on the 36-month overall survival using a time-dependent, multivariable, Cox proportional hazards model. The 36-month cumulative incidence of cardiovascular events, and the impact of cardiovascular comorbidities on the likelihood of cardiovascular events were evaluated using the Fine and Gray model, with death as a competing risk.

Results: We included 9222 patients (56.4% male; median age 73 years). Two-thirds (66.7%) had baseline cardiovascular comorbidities. The median 36-month overall survival was 20.4 [95% confidence interval (CI) 19.9-21.0] and 21.8 [95% CI 21.1-22.6] months in patients with and without cardiovascular comorbidities, respectively. Age ≥ 75 years, dependency in activities of daily living, radiotherapy, and another targeted therapy were identified as death risk factors, but not cardiovascular comorbidities. At 36 months, cardiovascular events had occurred in 60.2% [95% CI 58.9-61.4] and 44.1% [95% CI 42.3-45.9] of patients with and without cardiovascular comorbidities. Baseline venous thrombosis, female, three or more cardiovascular medications, another targeted therapy, and more than six bevacizumab injections were identified as risk factors for cardiovascular events.

Conclusions: In clinical practice, cardiovascular comorbidities before administering bevacizumab to older patients with metastatic colorectal cancer impacted the cardiovascular safety, but not overall survival. Unless they limit functional independency, older patients with cardiovascular comorbidities should be treated with bevacizumab under close monitoring.