Abstract 18913: Regional Variation in Heart Transplant Outcomes in the United States: Trends Over Time

Abstract

Background: Clinical outcomes after heart transplant have improved considerably in the United States over the past several decades. However, the degree to which this has occurred uniformly across the country is unknown. Methods: We used the Nationwide Inpatient Sample (NIS) databases to identify patients who received heart transplant (ICD 9 procedure codes 37.51) during the years 2003 through 2010. Using discharge weights an estimated 13,084 nationwide heart transplant patients were identified. Patients were stratified on the basis of hospitals’ census region as obtained from the AHA Annual Survey of Hospitals: Northeast (17%), Midwest (23%), South (29%), and West (31%). Multivariable logistic regression models were used to estimate the association of hospital region and in-hospital mortality. To estimate trends over time, a subsequent analysis was performed within strata of three time-periods: time-period 1 (2003-2005), time-period 2 (2006-2007) and time-period 3 (2008-2010). Results: Overall, in-hospital mortality was lowest in the West (4.2% versus 5.2% in the South, 5.6% in the Midwest, and 7.3% in the Northeast; P<0.001). After adjusting for patient demographics, co-morbidities, pay status, median household income status, and hospital characteristics, compared to the West, in-hospital mortality remained higher in the South (OR; 1.27; 95% CI, 1.01-1.60; P=0.037), Midwest (OR; 1.39; 95% CI, 1.10-1.76; P=0.006) and the Northeast (OR; 1.77; 95% CI, 1.39-2.27; P<0.001). When stratified by three time-periods, in-hospital mortality rates during time-period 1 were similar across all regions. Compared to the West, Northeast (OR, 5.84; P<0.001) and Midwest (OR, 1.91; P=0.019) had significant higher mortality rates during time-period 2. During time-period 3, Northeast (OR, 2.57; P<0.001), Midwest (OR, 1.92; P=0.002) and South (OR,1.67; P=0.019) regions had higher in-hospital mortality compared to the West. Conclusions: Regional differences in in-hospital mortality after heart transplant were not prevalent until 2006. The inpatient mortality remained worse in the Northeast, Midwest and South regions compared to the West. Further prospective studies are required to identify factors responsible for these regional differences.