1. Interhospital Transfers to MUSC
Marc Heincelman, MD

2. Background- Source of Admission
Emergency Dept
Clinic
MUSC Hospital
Referring Hospital

3. Background- Interhospital Transfers
Interhospital transfers (IHTs) account for approximately 3.5% of all hospital inpatient admissions (1.5 million per year)
At MUSC, 15-20% of all admissions are IHTs
IHT patients as a group are considered to be more complex with high resource utilization
National Administrative Datasets (NIS and UHC) have demonstrated worse
Steiner et al. The healthcare cost and utilization project: an overview. Effective clinical practice: ECP 2002;5:
Mueller et al. Inter-hospital transfer and patient outcomes: a retrospective cohort study. BMJ quality & safety 2018.
Nathens et al. The effect of interfacility transfer on outcome in an urban trauma system. The Journal of Trauma 2003;55:444-9.

4. Background- Interhospital Transfers
National administrative datasets have demonstrated worse outcomes among interhospital transfers (IHT) compared to patients admitted directly from the ED
Increased risk-adjusted mortality
Increased adverse events
Increased length of stay (LOS)
Increased cost
Decreased number of discharges to home
National Administrative Datasets (NIS and UHC) have demonstrated worse
Interhospital Transfer Patients Discharged by Academic Hospitalists. Sokol-Hessner et al. Journ Hosp Med

5. Background- Interhospital Transfers
Limitations of national administrative datasets
Unable to adjust for patient-level characteristics
Vitals
Labs
Individual diagnoses and comorbidities

6. Study Question
At MUSC, is IHT status independently associated with inpatient mortality after adjusting for more detailed patient-level clinical characteristics?

7. Hypothesis
IHT status will remain independently associated with inpatient mortality after adjusting for more detailed patient-level clinical characteristics?

8. Study Design
Retrospective cohort study of adults admitted to MUSC internal medicine services from
Primary outcome= in-hospital mortality
Independent variable of interest= IHT status
Covariates: admit service, patient demographics, disease-specific conditions, labs, vitals
Analysis= Cox proportional hazard regression analysis
Cox regression analysis

9. Study Design
4 Cox proportional hazard regression analyses will be performed to examine the independent association between IHT status and in-hospital mortality, controlling for covariates that may be potential confounders to the relationship between transfer and death.
Model 1- IHT status and admit service
Model 2- Model 1 + patient demographics
Model 3- Model 2 + comorbidities
Model 4- Model 3 + clinical variables

10. Study Population
Retrospective cohort study of 9328 adults admitted to MUSC internal medicine services from July 1, 2013 to June 30, 2014
Inclusion Criteria: All adults ≥18 years of age admitted to the following internal medicine services between July 1st, 2013 to June 30th, 2014 will be included: general internal medicine or internal medicine subspecialty services (medical intensive care unit (ICU), cardiology, gastroenterology, hepatology, or hematology/oncology services) if their records contain complete clinical data.
Exclusion Criteria: Patients will be excluded if their records do not contain complete clinical data necessary for analysis.
Cox regression analysis

11. Study Population
Retrospective cohort study of 9328 adults admitted to MUSC internal medicine services from July 1, 2013 to June 30, 2014
Target Population: Adult patients with admission source of interhospital transfer
Comparison Population: Adult patients with admission source of emergency department or clinic
Cox regression analysis

12. Retrospective Cohort IHT In-hospital Mortality No in-hospital
ED/Clinic
No in-hospital
Mortality

13. References
Steiner C, Elixhauser A, Schnaier J. The healthcare cost and utilization project: an overview. Effective clinical practice : ECP 2002;5:
Mueller S, Zheng J, Orav EJP, Schnipper JL. Inter-hospital transfer and patient outcomes: a retrospective cohort study. BMJ quality & safety 2018.
Nathens AB, Maier RV, Brundage SI, Jurkovich GJ, Grossman DC. The effect of interfacility transfer on outcome in an urban trauma system. The Journal of trauma 2003;55:444-9.
Sokol-Hessner L, White AA, Davis KF, Herzig SJ, Hohmann SF. Interhospital transfer patients discharged by academic hospitalists and general internists: Characteristics and outcomes. Journal of hospital medicine 2016;11:
Hernandez-Boussard T, Davies S, McDonald K, Wang NE. Interhospital Facility Transfers in the United States: A Nationwide Outcomes Study. Journal of patient safety 2017;13:

14. Questions?