Hospital readmissions: necessary evil or preventable target for quality improvement

Abstract

Objectives: To evaluate readmission rates and associated factors to identify potentially preventable readmissions.

Background: The decision to penalize hospitals for readmissions is compelling health care systems to develop processes to minimize readmissions. Research to identify preventable readmissions is critical to achieve these goals.

Methods: We performed a retrospective review of University HealthSystem Consortium database for cancer patients hospitalized from January 2010 to September 2013. Outcome measures were 7-, 14-, and 30-day readmission rates and readmission diagnoses. Hospital and disease characteristics were evaluated to evaluate relationships with readmission.

Results: A total of 2,517,886 patients were hospitalized for cancer treatment. Readmission rates at 7, 14, and 30 days were 2.2%, 3.7%, and 5.6%, respectively. Despite concern that premature hospital discharge may be associated with increased readmissions, a shorter initial length of stay predicted lower readmission rates. Furthermore, high-volume centers and designated cancer centers had higher readmission rates. Evaluating institutional data (N = 2517 patients) demonstrated that factors associated with higher readmission rates include discharge from a medical service, site of malignancy, and emergency primary admission. When examining readmission within 7 days for surgical services, the most common readmission diagnoses were infectious causes (46.3%), nausea/vomiting/dehydration (26.8%), and pain (6.1%).

Conclusions: A minority of patients after hospitalization for cancer-related therapy are readmitted with potentially preventable conditions such as nausea, vomiting, dehydration, and pain. However, most factors associated with readmission cannot be modified. In addition, high-volume centers and designated cancer centers have higher readmission rates, which may indicate that readmission rates may not be an appropriate marker for quality improvement.

Figure 1. Readmission by service

Within the UHC system, discharge from a medical service was associated with higher average rates of readmission at 7, 14, and 30-days (2.51%, 4.20%, and 6.55%) when compared to discharge from a surgical service (1.84% 2.88%, and 4.17%) (p<0.001 for all by two-sided Wilcoxon rank-sum test). Error bars represent one standard deviation.

Figure 2. Readmission by LOSa

Relationship between LOSa from initial hospitalization and readmission rate at (A) 7 days (p<0.0001), (B) 14 days (p<0.0001) and (C) 30 days (p<0.0001) with associated fitted robust linear regression and R² correlation value.

Figure 3. Readmission by LOSa for surgical patients

Relationship between LOSa from initial hospitalization for patients discharged from a surgical service and readmission rate at (A) 7 days (p<0.0001), (B) 14 days (p<0.0001) and (C) 30 days (p<0.0001) with associated fitted robust linear regression and R² correlation value.

Figure 4. Readmission by hospital volume

Relationship between LOSa from initial hospitalization and readmission rate at (A) 7 days (p<0.0001) and (B) 30 days (p<0.0001) for the entire cohort, or for just those patients discharged from a surgical service (C, D). The associated fitted robust linear regression is shown as is the R² correlation value for each relationship.

Figure 5. Readmission by NCI-Comprehensive Cancer Center Status

(A) Higher median rates of readmission at 7, 14, and 30-days (2.03%, 3.38%, and 5.05%) were observed for cancer patients treated at NCI-designated comprehensive cancer centers compared to non-designated centers (1.80% 2.79%, and 4.01%) (p<0.0001 for all time points by two-sided Wilcoxon rank-sum test). These findings persisted following evaluation of patients discharged from a surgical service (B) (p=0.02, p=0.0002, p<0.0001 by two-sided Wilcoxon rank-sum test). Error bars represent one standard deviation.

Figure 6. Readmission by physician volume

Relationship between individual physician volume and (A) 7 day, (B) 14 day, and (C) 30day readmission rates at UCDMC. The associated fitted robust linear regression is shown as is the R² correlation value for each relationship.

Figure 7. Readmission by type of admission for index hospitalization

Readmission rate at 7 days, 14 days, and 30 days following index hospitalization classified as elective, urgent, or emergency among the 2505 patients hospitalized at UCMDC.