Cardiovascular risks of PD1 inhibitor therapy in cancer: impact of prior ischemic events on heart failure - a retrospective cohort study

Immune checkpoint inhibitors (ICIs) have transformed cancer therapy, but concerns remain about their cardiac risks. Limited recent basic evidence suggests a possible link between ICIs that target PD1 and adverse cardiac events such as heart failure.

This study explores the connection between PD1 inhibitor therapy and incident heart failure in cancer patients.

In our retrospective study at a tertiary medical center, 1,671 cancer patients receiving PD1 inhibitors were analyzed. Individuals with a history of heart failure, who developed myocarditis on PD-1, or had missing data were excluded. Data from pharmacy records and the Research Patient Data Registry provided clinical and ICI-related details. Cases were defined as patients who developed incident heart failure after ICI started. Controls were patients who did not develop incident heart failure after ICI start. Sensitivity analyses, including propensity score matching and comparison with non-ICI-treated cancer patients, ensured result robustness. Multivariate logistic regressions were performed.

Among 1,671 ICI treated patients, 109 (6.5%) developed heart failure without evidence of myocarditis over a median follow-up of 332.0 days. In both the full cohort and the 3:1 matched cohort (n=380), multivariate logistic regression showed increased odds of incident heart failure in patients with prior ischemic cardiac events: 2.34 (95%CI 1.26-4.16, p=0.005) and 2.11 (95%CI 1.05-4.2, p=0.033) respectively. Among the non-ICI treated cancer patients, multivariate logistic regression found no association between prior ischemic events and incident heart failure (1.23, 95%CI 0.53-2.63, p=0.6), but hypertension showed an association (1.74, 95%CI 1.07-2.87, p=0.027).

This study emphasizes vigilance for cardiovascular complications in PD1 inhibitor-treated cancer patients. The incidence of heart failure was 6.5% over a follow-up period of less than 1 year. Prior ischemic events correlate with increased heart failure risk, suggesting a need for nuanced patient management. Understanding ICIs' cardiovascular safety is crucial for risk assessment, treatment optimization, and patient well-being.