Abstract 128: The Impact of Hospital Acquisition by a Health System on Admission Allocation

Abstract

Background: The optimal choice of hospital for a particular patient’s admission depends on many factors and many reasons may explain why a patient might not be admitted to the hospital that is best able to meet their needs (e.g. incomplete information about the patient, payment incentives, hospital capacity and hospital affiliation of the clinician making the hospital selection decision). Health systems that include both teaching and community hospitals should be well positioned to improve the allocation of patients to the most appropriate care setting - triaging complex patients or those with serious illnesses to teaching hospitals while triaging healthier patients or those with less severe illnesses to community hospitals. The aim of this study is to determine the impact of health system organization on the allocation of patients with common cardiovascular conditions. Methods: Using a difference in differences model, we estimated the proportion of admissions originating from a hospital’s primary service area (PSA) before and after acquisition by a health system. We then stratified patients based on the reason for admission and severity of illness. Admissions were classified as “emergent” or life-threatening, “urgent” requiring prompt medical attention but not immediately life-threatening or “elective.” Most cardiology admissions were emergent (i.e. acute coronary syndrome, shock) or urgent (i.e. heart failure exacerbation). Results: Overall, patients who lived in the PSA of a community hospital were 1% more likely to be admitted to a teaching hospital after their community hospital was acquired by a health system that included a teaching hospital. When stratified by admission type, this effect was most pronounced for urgent admissions where patients were 11.3% (p<0.001) more likely to be admitted to a teaching hospital (versus their local community hospital) after acquisition of the community hospital by a health system that included a teaching hospital. Elective admissions were also 1.5% (p<0.01) more likely to occur at the teaching hospital after acquisition of the community hospital by a health system that included a teaching hospital. The acquisition of a community hospital by a health system that included a teaching hospital had no impact on the distribution of emergency (life-threatening) admissions. Conclusions: Acquisition of a community hospital by a health system that includes a teaching hospital increased the rate of urgent and elective admissions from the community to a teaching hospital. The was particularly true for urgent admissions, including many cardiology admissions. The impact of this trend on patient outcomes and the cost of care merits future study.