Date Published: July 10, 2017
Publisher: Public Library of Science
Author(s): Jordan B. Strom, Daniel B. Kramer, Yun Wang, Changyu Shen, Jason H. Wasfy, Bruce E. Landon, Elissa H. Wilker, Robert W. Yeh, Zhanjun Jia.
Few studies have examined rates and causes of short-term readmissions among adults across age and insurance types. We compared rates, characteristics, and costs of 30-day readmission after all-cause hospitalizations across insurance types in the US. We retrospectively evaluated alive patients ≥18 years old, discharged for any cause, 1/1/13-11/31/13, 2006 non-federal hospitals in 21 states in the Nationwide Readmissions Database. The primary stratification variable of interest was primary insurance. Comorbid conditions were assessed based on Elixhauser comorbidities, as defined by administrative billing codes. Additional measures included diagnoses for index hospitalizations leading to rehospitalization. Hierarchical multivariable logistic regression models, with hospital site as a random effect, were used to calculate the adjusted odds of 30-day readmissions by age group and insurance categories. Cost and discharge estimates were weighted per NRD procedures to reflect a nationally representative sample. Diagnoses for index hospitalizations leading to rehospitalization were determined. Among 12,533,551 discharges, 1,818,093 (14.5%) resulted in readmission within 30 days. Medicaid insurance was associated with the highest adjusted odds ratio (AOR) for readmission both in those ≥65 years old (AOR 1.12, 95%CI 1.10–1.14; p <0.001), and 45–64 (AOR 1.67, 95% CI 1.66–1.69; p < 0.001), and Medicare in the 18–44 group (Medicare vs. private insurance: AOR 1.99, 95% CI 1.96–2.01; p <0.001). Discharges for psychiatric or substance abuse disorders, septicemia, and heart failure accounted for the largest numbers of readmissions, with readmission rates of 24.0%, 17.9%, 22.9% respectively. Total costs for readmissions were 50.7 billion USD, highest for Medicare (29.6 billion USD), with non-Medicare costs exceeding 21 billion USD. While Medicare readmissions account for more than half of the total burden of readmissions, costs of non-Medicare readmissions are nonetheless substantial. Medicaid patients have the highest odds of readmission in individuals older than age 44, commonly due to hospitalizations for psychiatric illness and substance abuse disorders. Medicaid patients represent a population at uniquely high risk for readmission.
Unplanned readmissions after hospital discharge are common, costly, and an important contributor to health care utilization. More than half of Medicare beneficiaries are readmitted within one year of discharge, accounting for billions of expenditures annually beyond those associated with the index admissions [1–3]. Accordingly, reducing hospital readmissions has become a national health care priority. The Patient Protection and Affordable Care Act  authorized the Department of Health and Human Services to establish a Hospital Readmissions Reduction Program, which utilizes hospital-based payment incentives to curb readmissions. Subsequently, the Centers for Medicare and Medicaid Services (CMS) implemented mandatory public reporting of and conditional reimbursement for 30-day risk standardized readmission measures for five common medical conditions or surgical procedures .
While prior examinations of short-term hospital readmissions have focused primarily on the Medicare population, this study identified the considerable number and cost of non-Medicare readmissions, as well as the high burden of readmission among patients admitted for psychiatric disease and substance abuse disorders. Non-Medicare readmissions accounted for 44% of all readmissions in the US and more than 20 billion USD in direct costs in 2013. In examining relative rates of readmissions across all age and insurance categories, we found that Medicaid-insured patients accounted for high rates of readmission in all but the youngest age group. In the non-elderly group, and particularly in the young Medicare and Medicaid populations, psychiatric disease and substance abuse were the most important contributors to rehospitalization, representing a tenth of all discharges leading to readmission, and almost one fifth of discharges leading to readmission in the Medicare and Medicaid insured population. As individuals may become eligible for Medicare after two years of disability payments , the young Medicare group additionally represents a distinct group at uniquely high risk of readmission, as shown by Medicare patients having the highest rate of readmission in the youngest age group.
While Medicare readmissions account for more than half of the total burden of readmissions, non-Medicare readmissions are frequent and are associated with substantial cost. Psychiatric disease, substance abuse, and chronic illness are frequently associated with rehospitalization in the non-Medicare population.