Heart Failure Related Hospitalizations Are Associated with Increased Morbidity and Mortality in Pediatric Oncology Patients

Introduction: Cardiomyopathy is a well-described complication of cancer therapy in pediatric patients. However, the prevalence and outcomes of heart failure related hospitalizations in these patients are unknown. We hypothesize that while heart failure related hospitalizations are uncommon in pediatric oncology patients, they are likely associated with increased morbidity and mortality.

Methods: We performed retrospective analysis of the Healthcare Cost and Utilization Project Kids' Inpatient Database, a nationwide database of pediatric hospitalizations in the United States, for oncology patients with and without heart failure for years 2000, 2003, 2006, and 2009.

Results: Heart failure was identified in 914 of 259,432 (0.4%) pediatric oncology admissions. Patients with heart failure were more likely to be non-white (52.2 vs 43%, p<0.001), less likely to be in the highest income bracket (23.9 vs 27.5%, p=0.014), more likely to have leukemia (40.7 vs 31.3%, p<0.001), and more likely to undergo bone marrow transplantation on admission (5.0 vs 1.6%, p<0.001). Several morbidities were significantly more common in patients with heart failure including respiratory failure [16.4% vs 1.3%, odds ratio (OR) 14.6, 95% CI 12.2-17.4), sepsis (21.9% vs 7.2%, OR 3.6, 95% CI 3.1-4.3), stroke (1.5% vs 0.6%, OR 2.5, 95% CI 1.5-4.3), and renal failure (11.7% vs 1.2%, OR 10.9, 95% CI 8.9-13.3). Length of stay (LOS) and hospital charges were also significantly greater in oncology patients with heart failure patients compared to those without; median LOS 9 (IQR 4-25) vs 4 days (IQR 2-6); median hospital charges $58,023 (IQR 18,835-169,826) vs $18,161 (IQR 8,860-39,640); p<0.001 for both. Hospital mortality was significantly greater in oncology patients with heart failure compared to those without (13.3% vs 1.3%; OR 11.5, 95% CI 9.5-14.0). On multivariable analysis, heart failure was independently associated with hospital mortality in pediatric oncology patients (OR 2.21, 95% CI 1.63-3.00).

Conclusion: Heart failure is an uncommon but serious complication in hospitalized pediatric oncology patients. The presence of heart failure was associated with increased morbidities, resource utilization, and mortality. Further study is needed for the prevention and treatment of heart failure in this population.