Preoperative Activities of Daily Living Dependency is Associated With Higher 30-Day Readmission Risk for Older Adults After Total Joint Arthroplasty
Authors: Falvey Jason R. , Bade Michael J. , Hogan Craig , Forster Jeri E. , Stevens-Lapsley Jennifer E. 
Published: November 2019

Abstract

Background
With recent Medicare payment changes, older adults are increasingly likely to be discharged home instead of to extended care facilities after total joint arthroplasty (TJA), and may therefore be at increased risk for readmissions. Identifying risk factors for readmission could help re-align care pathways for vulnerable patients; recent research has suggested preoperative dependency in activities of daily living (ADL) may increase perioperative and postoperative surgical complications. However, the proportion of older surgical patients with ADL dependence before TJA, and the impact of ADL dependency on the frequency and timing of hospital readmissions is unknown.

Questions/purposes
(1) What proportion of older adults discharged home after TJA have preoperative ADL dependency? (2) Is preoperative ADL dependency associated with increased risk of hospital readmissions at 30 days or 90 days for older adults discharged home after TJA?

Methods
This was a retrospective cohort analysis of 6270 Medicare fee-for-service claims from 2012 from a 5% national Medicare sample for older adults (older than 65 years) receiving home health care after being discharged to the community after elective TJA. Medicare home health claims were used for two reasons: (1) the primary population of interest was older adults and (2) the accompanying patient-level assessment data included an assessment of prior dependency on four ADL tasks. Activities of daily living dependency was dichotomized as severe (requiring human assistance with all four assessed tasks) or partial/none (needing assistance with three or fewer ADLs); this cutoff has been used in prior research to evaluate readmission risk. Multivariable logistic regression models, clustered at the hospital level and adjusted for known readmission risk factors (such as comorbidity status or age), were used to model the odds of 30- and 90- day and readmission for patients with severe ADL dependence.

Results
Overall, 411 patients were hospitalized during the study period. Of all readmissions, 64% (262 of 411) occurred within the first 30 days, with a median (interquartile range [IQR]) time to readmission of 17 days (5 to 46). Severe ADL dependency before surgery was common for older home health recipients recovering from TJA, affecting 17% (1066 of 6270) of our sample population. After adjusting for clinical covariates, severe ADL dependency was not associated with readmissions at 90 days (adjusted odds ratio = 1.20 [95% CI 0.93 to 1.55]; p = 0.15). However, severe preoperative ADL dependency was associated with higher odds of readmission at 30 days (adjusted OR = 1.45 [95% CI 1.11 to 1.99]; p = 0.008).

Conclusions
Severe preoperative ADL dependency is modestly associated with early but not late hospital readmission after TJA. This work demonstrates that it may important to apply a simple screening of ADL dependency preoperatively so that surgeons can guide changes in care planning for older adults undergoing TJA, which may include participation in preoperative rehabilitation (pre-habilitation) or more aggressive follow-up in the 30 days after surgery. Further research is needed to determine whether severe ADL dependence can be modified before surgery, and whether these changes in dependency can reduce readmission risk after TJA.

Level of Evidence
Level III, therapeutic study.