LOW INCOME IS AN INDEPENDENT PREDICTOR OF IN-HOSPITAL MORTALITY AMONG HEART TRANSPLANT RECIPIENTS: A NATIONWIDE INPATIENT SAMPLE STUDY


Wilbert S. Aronow, M.D., New York Medical College, NY, U.S.A.

Background: Lower socio-economic condition has been shown to have greater risk of rejection and graft loss among heart transplant recipients who survive the transplant hospitalization. However, the association of income status and in-hospital outcomes among heart transplant recipients have not been studied from a national database.

Methods: Hospitalized patients (N=3418) with elective heart transplant procedure (ICD-9 procedure code 37.51) in the nationwide inpatient sample (NIS) 2003 through 2010 databases were identified. Socio-economic status of a patient was determined by median household income (MHI) for patient's ZIP Code (based on respective year) and were categorized by MHI quartile 1, 2, 3 and 4. Discharge weights were used to create nationwide estimates. Multivariable logistic regression models were used to determine the associations of MHI and inpatient mortality, length of stay and total costs among these patients.

Results: Patients had a mean age of 49(±17) years, 27% women, 36% non-whites. The risk of in-hospital mortality in the MHI quartile 2 and 3 were similar to that of the highest income group (adj.ORs, 95%CIs were 1.30; 0.82–2.09; p=0.268 and 0.77; 0.47–1.27; p=0.309, respectively); however, MHI quartile 1 had higher risk of in-hospital mortality (adj.OR, 1.73; 95%CI, 1.03–2.90; p=0.039). Income status had no association with length of hospital stay and total cost.

Conclusion: In this large national database, lowest quartile of MHI was an independent predictor of in-hospital mortality among heart transplant recipients. Further prospective studies with more complete and direct measurement of socioeconomic status may be needed to evaluate this association.