Cardiovascular-related hospital visits amongst oncology patients receiving immune checkpoint inhibitors: A population-based cohort study.

Introduction: Immune checkpoint inhibitors (ICIs) have substantially improved the clinical outcomes for many cancer patients. However, these treatments are potentially associated with serious cardiovascular adverse events.

Methods: We identified a population-based, retrospective cohort of oncology patients who started ICIs treatments between September 1st, 2012 and August 31st, 2019, in Ontario, Canada. The primary outcome was the incidence of cardiovascular-related hospital visits between initiation of ICI to 90 days after the last dose of ICI. Cumulative incidence functions were used to estimate the incidence of cause-specific cardiovascular-related hospital visits, accounting for the competing risks of all-cause mortality.

Results: A total of 5725 cancer patients (median age 68 years and 59.4 % male) received ICI, of which 556 (9.7 %) individuals had hospital visits due to cardiovascular-related adverse events. Amongst patients with cardiovascular-related hospital visits, 284 (51 %) were hospitalized and 88 (15.8 %) required intensive care unit monitoring. Of the 0.9 % hospital visits due to myocarditis or pericarditis, the median time from ICI initiation to hospital visits was 63 days (Q1-Q3: 23-128). The one-year cumulative incidence of cardiovascular-related hospital visit was higher for patients with prior cardiovascular history (15.2 %; 95 % CI: 12.2-18.4 %) than those without (8.7 %; 95 % CI: 7.9-9.5 %) (p < 0.001). Amongst the 9.7 % ICI-treated patients with cardiovascular-related hospital visits, the median overall survival was 2.9 months (95 % CI: 2.24-3.52). Patients who required ICU stay had worse survival outcomes (median OS = 2.1 months) compared to those who were not hospitalized for the cardiovascular-related hospital visits (median OS = 2.5 months).

Conclusion: In a population-based study, cancer patients treated with ICIs had a high incidence of cardiovascular-related hospital visits. Patients with prior cardiac disease are more likely to have a cardiovascular-related hospital visit. The survival outcomes following cardiovascular-related hospital visits is poor amongst cancer patients treated with ICI.