Long-term Survival After Heart Transplantation: A Population-based Nested Case-Control Study

Heart transplantation is the mainstay of treatment for patients in end-stage heart failure. This study sought to contrast survival after transplantation with that of the general population to quantify standardized mortality rates using a nested case-control study design.

Control subjects were noninstitutionalized inhabitants of the United States identified through the National Longitudinal Mortality study. Case subjects were adults who underwent heart transplantation between 1990 and 2007 and identified through the Organ Procurement and Transplantation Network. Propensity-matching (5:1, nearest neighbor, caliper = 0.1) was utilized to identify suitable control subjects based on age, sex, race, and state of permanent residency. The primary study endpoint was 10-year survival.

In all, 31,883 heart transplant recipients were matched to 159,415 noninstitutionalized residents of the United States. The 10-year survival of heart transplant recipients was 53%. The population expected mortality rate was 15.9 deaths per 100 person-years with an observed rate of 45.1 deaths per 100 person-years (standardized mortality rate [SMR] 2.84; 95% confidence interval, 2.82 to 2.87). The broadest gaps between observed and expected survival were evident in female (SMR 3.63), black (SMR 3.67), and Hispanic (SMR 4.12) recipients. Standardized mortality ratios declined over time (1990 to 1995, 3.09; 1996 to 2000, 2.90; 2001 to 2007, 2.58). The long-term standardized survival of older recipients was closest to that expected for their age.

Heart transplant recipients have considerable long-term survival and have a threefold higher standardized long-term mortality rate than that of the noninstitutionalized population. Long-term mortality rates have consistently declined over time and will likely continue to decrease.