Considering Mobility Status and Home Environment in Readmission Risk After Total Knee Arthroplasty

Abstract

Background: Discharge disposition following total knee arthroplasty (TKA) offers varying levels of post-acute care monitoring depending on the medical status of the patient and his or her ability to function independently. Discharge disposition following TKA is associated with 30-day and 90-day hospital readmission, but prior studies have not consistently considered confounding due to mobility status after TKA, available caregiver support, and measures of home area deprivation. The purpose of this study was to examine 30-day and 90-day readmission risk for patients discharged to a skilled nursing facility (SNF) following TKA after controlling specifically for these factors, among other covariates.

Methods: This was a retrospective cohort study of patients undergoing TKA at any of 11 hospitals in a single, large, academic health-care system between January 2, 2017, and August 31, 2022, who were discharged to an SNF or home health care (HHC). The adjusted relative risk of readmission within 30 and 90 days of discharge to an SNF compared with HHC was estimated using modified Poisson regression models.

Results: There were 15,212 patients discharged to HHC and 1,721 patients discharged to SNFs. Readmission within 30 days was 7.1% among patients discharged to SNFs and 2.4% among patients discharged to HHC; readmission within 90 days was 12.1% for the SNF group and 4.8% for the HHC group. The adjusted relative risk after discharge to an SNF was 1.07 (95% confidence interval [CI], 0.79 to 1.46; p = 0.65) for 30-day readmission and 1.45 (95% CI, 1.16 to 1.82; p < 0.01) for 90-day readmission.

Conclusions: Discharge to an SNF compared with HHC was independently associated with 90-day readmission, but not with 30-day readmission, after controlling for mobility status after TKA, available caregiver support, and home Area Deprivation Index, among other covariates.

Level of evidence: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.