Cardiac events among a cohort of 17,389 patients receiving cancer chemotherapy: short and long term implications.

Abstract

Background: The association between cardiovascular disease and carcinogenesis is bidirectional and well-established. Furthermore, cancer treatment improves overall patient survival, potentially at the cost of incremental and fatal cardiovascular disease (CVD).

Aim: To evaluate (a) In a real-world cohort, the proportion of patients offered cancer chemotherapy who have antecedent CVD (CVD_A); (b) The rates of patient admission with subsequent development of CVD (CVD_S) requiring hospital admission post assignment to chemotherapy; (c) The impact of CVD_A and CVD_S on mortality rates relative to those seen in patients without overt CVD (CVD^-) and (d) The time course of mortality in CVD^- versus CVD_S patients.

Methods: Retrospective analysis was performed in deidentified linked health data sets. Correlates of mortality were evaluated by Cox proportional hazards evaluation. Relative and absolute time-variability of CVD as a primary cause of death were determined.

Results: Of the total 17,389 patients, there were 2,159 with CVD_A. Over a median follow-up time of 4.6 years, CVD_S admissions (n = 8,529) occurred more commonly in the presence of CVD_A (70.0% vs. 46.1%, p < 0.001), and more than 50% of CVD_S cases occurred in the first 12 months of follow-up. The 5-year mortality rates were 71.5% for CVD_A, 64.7% for CVD_S, and 40.8% for CVD^- (p < 0.001). Development of CVD_S was associated with a substantially increased risk of mortality in the next 12 months. The development of CVDs was also associated with an increased risk of cardiovascular, as against non-cardiovascular, mortality (7.1% vs. 1.6%, p < 0.001).

Conclusions: Approximately 50% of patients assigned to cancer chemotherapy developed CVD_S, heralding a particularly high risk of mortality over the next 12 months. Both CVD_A and CVD_S are associated with substantial increases in mortality rates relative to those in CVD^- patients. This increased risk merits close individual monitoring.