Hospital readmission is an admission to a hospital following an initial hospitalization. A
common readmission timeframe measured by organizations such as the Centers for Medicare
and Medicaid Services (CMS) is readmissions within 30 days of the index hospitalization [1].
Readmissions are considered undesirable clinical outcomes because they suggest that the
patient was discharged prematurely from the initial hospitalization or that the posthospitalization
care was sub-optimal. In 2009, Jencks et al. reported that of 11.9 million
Medicare beneficiaries discharged from a U.S. hospital within a 15-month period from 2003
to 2004, 19.6% of the patients were readmitted within 30 days, with unplanned
hospitalizations leading to $17.4 billion in excess costs to Medicare in 2004 [2]. Moreover,
an index visit for congestive heart failure (CHF) was followed by a readmission in 26.9% of
cases in this study, with CHF representing the most common reason for an index visit leading
to a readmission. The CMS Readmissions Reduction Program provides a financial incentive
for hospitals to reduce readmissions, as high rates of readmissions for CHF and several other
conditions can lead to an assessment of financial penalties to hospitals