Association of Post-discharge Service Types and Timing with 30-Day Readmissions, Length of Stay, and Costs

Abstract

Background: Although early follow-up after discharge from an index admission (IA) has been postulated to reduce 30-day readmission, some researchers have questioned its efficacy, which may depend upon the likelihood of readmission at a given time and the health conditions contributing to readmissions.

Objective: To investigate the relationship between post-discharge services utilization of different types and at different timepoints and unplanned 30-day readmission, length of stay (LOS), and inpatient costs.

Design, setting, and participants: The study sample included 583,199 all-cause IAs among 2014 Medicare fee-for-service beneficiaries that met IA inclusion criteria.

Main measures: The outcomes were probability of 30-day readmission, average readmission LOS per IA discharge, and average readmission inpatient cost per IA discharge. The primary independent variables were 7 post-discharge health services (institutional outpatient, primary care physician, specialist, non-physician provider, emergency department (ED), home health care, skilled nursing facility) utilized within 7 days, 14 days, and 30 days of IA discharge. To examine the association with post-discharge services utilization, we employed multivariable logistic regressions for 30-day readmissions and two-part models for LOS and inpatient costs.

Key results: Among all IA discharges, the probability of unplanned 30-day readmission was 0.1176, the average readmission LOS per discharge was 0.67 days, and the average inpatient cost per discharge was $5648. Institutional outpatient, home health care, and primary care physician visits at all timepoints were associated with decreased readmission and resource utilization. Conversely, 7-day and 14-day specialist visits were positively associated with all three outcomes, while 30-day visits were negatively associated. ED visits were strongly associated with increases in all three outcomes at all timepoints.

Conclusion: Post-discharge services of different types and at different timepoints have varying impacts on 30-day readmission, LOS, and costs. These impacts should be considered when coordinating post-discharge follow-up, and their drivers should be further explored to reduce readmission throughout the health care system.

Keywords: Hospital Readmission Reduction Program; all-cause index admission; post-discharge services utilization; service types; unplanned 30-day readmission.

Figure 1

Post-discharge health services utilization within 7 days, 14 days, and 30 days of discharge from index admission (n = 583,199).

Figure 2

Association of post-discharge health services utilization within 7 days, 14 days, and 30 days of discharge from index admission with unplanned 30-day readmission (n = 583,199). Notes: (i) In multivariable logistic models, odds ratio (OR) and 95% confidence interval (CI) were adjusted for 7 different types of post-discharge care (institutional outpatient, primary care physician, specialist, non-physician provider, emergency department, home health care, skilled nursing facility) and all other explanatory variables listed in Table 2. (ii) p <0.05 if 95% CI does not include one. (iii) Full estimation results are presented in Appendix Table 1, panel A.

Figure 3

Association of post-discharge health services utilization within 7 days, 14 days, and 30 days of discharge with 30-day readmission hospital length of stay (a) and readmission inpatient costs (b) (n = 583,199). Notes: (i) In multivariable two-part models, average marginal effect (AME) and 95% confidence interval (CI) were adjusted for 7 different types of post-discharge care (institutional outpatient, primary care physician, specialist, non-physician provider, emergency department, home health care, skilled nursing facility) and all other explanatory variables listed in Table 2. (ii) The AME represents the difference in adjusted predicted outcome (i.e., 30-day readmission hospital length of stay per IA discharge, and inpatient costs per IA discharge) between patients who did and did not utilize each post-discharge service. (iii) p <0.05 if 95% CI does not include zero. (iv) Full estimation results for 30-day readmission length of stay, and costs are presented in Appendix Tables 2 and 3 (panel A), respectively.