Objective: The average age of heart transplant recipients in the United States has been increasing over the past decade. The effect of age on outcomes following heart transplantation, including cost and readmission has yet to be thoroughly evaluated.
Methods: All Medicare fee-for-service patients undergoing heart transplantation between 2008 and 2013 were included in the study. Denominator files were used to collect patient demographics and mortality. Kaplan-Meier survival estimates and Cox Proportional Hazards models were used for overall survival analysis.
Results: A total of 4431 heart transplant patients were included in this study. Patients were broken down into categories of age <60, 60-69, and >70. Patients >70 were more likely to be male, white and have CAD and ischemic cardiomyopathy than patients <60. Multivariable cox survival model showed ECMO (HR 9.5, 95% CI 7.7 - 11.6, p < 0.01) and liver disease (HR 1.6 95% CI 1.2 - 2.2, p < 0.01) were associated with increased long-term mortality (p<0.01 and p=0.02, respectively). There was a significant difference in ECMO usage between patient groups with 6% of patents > 70, 4% of patients 60-69, and 3% of patients < 60 requiring ECMO (p=0.05). There was no significance was seen in 30 day mortality rates among between patients > 70 (5%) and patients < 70 years of age (5% ), p=0.83. Additionally, there was no difference between ICU lengths of stay, 30- and 90-day readmission rates (p=1.0 and p=0.72 respectively), and hospital length of stay (p=0.35) (Table 1).
Conclusions: Among Medicare patients undergoing heart transplantation, those over the age of 70 had no difference in terms of survival and cost utilization compared to younger patients. Heart transplantation programs are doing a good job of selecting older patients in order to maintain these outcomes. Age was associated with increased use of ECMO, and ECMO adversely affected long-term survival.