The relationship of post-acute home care use to Medicaid utilization and expenditures

Abstract

Research objectives: To describe the use of post-acute home care (PAHC) and total Medicaid expenditures among hospitalized nonelderly adult Medicaid eligibles and to test whether health services utilization rates or total Medicaid expenditures were lower among Medicaid eligibles who used PAHC compared to those who did not.

Study population: 5,299 Medicaid patients aged 18-64 discharged in 1992-1996 from 29 hospitals in the Cleveland Health Quality Choice (CHQC) project.

Data sources: Linked Ohio Medicaid claims and CHQC medical record abstract data.

Data extraction: One stay per patient was randomly selected.

Design: Observational study. To control for treatment selection bias, we developed a model predicting the probability (propensity) a patient would be referred to PAHC, as a proxy for the patient's need for PAHC. We matched 430 patients who used Medicaid-covered PAHC ("USE") to patients who did not ("NO USE") by their propensity scores. Study outcomes were inpatient re-admission rates and days of stay (DOS), nursing home admission rates and DOS, and mean total Medicaid expenditures 90 and 180 days after discharge.

Principal findings: Of 3,788 medical patients, 12.1 percent were referred to PAHC; 64 percent of those referred used PAHC. Of 1,511 surgical patients, 10.9 percent were referred; 99 percent of those referred used PAHC. In 430 pairs of patients matched by propensity score, mean total Medicaid expenditures within 90 days after discharge were $7,649 in the USE group and $5,761 in the NO USE group. Total Medicaid expenditures were significantly higher in the USE group compared to the NO USE group for medical patients after 180 days (p < .05) and surgical patients after 90 and 180 days (p < .001). There were no significant differences for any other outcome. Sensitivity analysis indicates the results may be influenced by unmeasured variables, most likely functional status and/or care-giver support.

Conclusions: Thirty-six percent of the medical patients referred to PAHC did not receive Medicaid-covered services. This suggests potential underuse among medical patients. The high post-discharge expenditures suggest opportunities for reducing costs through coordinating utilization or diverting it to lower-cost settings. Controlling for patients' need for services, PAHC utilization was not associated with lower utilization rates or lower total Medicaid expenditures. Medicaid programs are advised to proceed cautiously before expanding PAHC utilization and to monitor its use carefully. Further study, incorporating non-economic outcomes and additional factors influencing PAHC use, is warranted.

Figure 1

Overview of the Study Design

Figure 2

Differences in Mean Total Medicaid Expenditures in Dollars between Patients Using Post-acute Home Care (“Use”) and Patients Not Using Post-Acute Home Care (“No Use”) by the Type of Service, 282 Pairs of Medical Stays Matched by Propensity Score

Figure 3

Differences in Mean Total Medicaid Expenditures in Dollars between Patients Using Post-acute Home Care (“Use”) and Patients Not Using Post-acute Home Care (“No Use”) by the Type of Service, 148 Pairs of Surgical Stays Matched by Propensity Score.