Indications For Hospital Admissions and Outcomes Of Hospitalization Among Multiple Myeloma Patients In The U.S: Data From National Inpatient Sample

A recent Spanish study suggested an impact of the type of hospital (teaching versus non-teaching) on survival of multiple myeloma (MM) patients. Such data, as well as other hospitalization parameters such as indications, length of stay (LOS), in-hospital mortality (IHM)  in MM patients admitted to hospitals in the U.S are lacking. We have explored the National Inpatient sample (NIS) data to address the indications for hospitalization in MM patients and their survival outcomes of the hospitalization.

We obtained the National Inpatient Sample (NIS) data for the years 01/2001 until 12/2010 from Healthcare Cost and Utilization Project database (HCUP) database. The 2010 NIS contains all discharge data located in 45 States, approximating a 20% stratified sample of the U.S hospitals. Teaching hospital was defined as a hospital supported by AMA-approved residency program, is a member of the council of teaching hospitals or has a ratio of full-time equivalent interns and residents to beds of ≥0.25.

A total of 178354 admissions reported to NIS were analyzed. Majority of admissions were to teaching hospitals (61.7% admissions: 45.8% for non-SCT and 15.9% for SCT indications) (Table 1). Among the patients that were admitted for non-SCT indications, significantly younger patients were admitted to teaching hospitals. Complicated procedures such as cancer chemotherapy were admitted to teaching hospitals (teaching vs. non-teaching: 8.3% vs. 3.4%; p=<0.0001) and simple procedures such as blood transfusions were admitted to non-teaching hospitals (teaching vs. non-teaching: 13% vs. 19.2%; p=<0.0001). The IHM is significantly increased in non-teaching hospitals (teaching vs. non-teaching: IHM: 9.8 vs. 12.5%; p=<0.0001). Among the patients that were admitted for SCT as the primary procedure, IHM for autologous SCT is 1.64% and for allogeneic SCT is 5.94%.

This analysis suggests inferior survival outcomes in MM patients admitted to non-teaching hospitals. Despite the difference in severity of admissions, IHM is significantly increased in non-teaching hospitals. This effect is at least partially attributable to older patient admissions. IHM in SCT admissions is similar to published literature, validating our findings.

Kaufman:Onyx: Consultancy; Celgene: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Janssen: Consultancy; Millenium: Consultancy; Merck: Research Funding. Boise:Onyx Pharmaceuticals: Consultancy. Lonial:Millennium: Consultancy; Celgene: Consultancy; Novartis: Consultancy; BMS: Consultancy; Sanofi: Consultancy; Onyx: Consultancy.